132 tech intro cd ma

February, 2008 132 - 1Technical Introduction to CDMA v6 (c) 2008 Scott Baxter

Technical Introduction to CDMA

Technical Introduction to CDMA

Course 132

IS-95, CDMA2000 and a glimpse of 1xEV


Course Outline

Basic CDMA Principles• Coding• Forward and Reverse Channels

CDMA Operational Details• Multiplexing, Forward and Power Control

CDMA Network ArchitectureCDMA MessagingCDMA Handset ArchitectureCDMA Handoff PrinciplesCDMA System Acquisition and Call Flow ExamplesIntroduction to Optimization and Optimization ToolsWhat’s New in CDMA2000?

• 1xEV-DO, 1xEV-DV features and internal structure


Section A

How Does CDMA Work?Introduction to Basic Principles

How Does CDMA Work?Introduction to Basic Principles


Claude Shannon: The Einstein of Information Theory

The core idea that makes CDMA possible was first explained by Claude Shannon, a Bell Labs research mathematicianShannon's work relates amount of information carried, channel bandwidth, signal-to-noise-ratio, and detection error probability

• It shows the theoretical upper limit attainable

In 1948 Claude Shannon published his landmark paper on information theory, A Mathematical Theory of Communication. He observed that "the fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point." His paper so clearly established the foundations of information theory that his framework and terminology are standard today.Shannon died Feb. 24, 2001, at age 84.

SHANNON’S CAPACITY EQUATION

C = Bω log2 [ 1 + ]S N

Bω = bandwidth in HertzC = channel capacity in bits/secondS = signal powerN = noise power


CDMA: Using A New Dimension

All CDMA users occupy the same frequency at the same time! Frequency and time are not used as discriminatorsCDMA operates by using CODING to discriminate between usersCDMA interference comes mainly from nearby usersEach user is a small voice in a roaring crowd -- but with a uniquely recoverable code

CDMA

Figure of Merit: C/I(carrier/interference ratio)

AMPS: +17 dBTDMA: +14 to +17 dB

GSM: +7 to 9 dB.CDMA: -10 to -17 dB.CDMA: Eb/No ~+6 dB.


Two Types of CDMA

There are Two types of CDMA:Frequency-Hopping

• Each user’s narrowband signal hops among discrete frequencies, and the receiver follows in sequence

• Frequency-Hopping Spread Spectrum (FHSS) CDMA is NOTcurrently used in wireless systems, although used by the military

Direct Sequence• narrowband input from a user is

coded (“spread”) by a user-unique broadband code, then transmitted

• broadband signal is received; receiver knows, applies user’s code, recovers users’ data

• Direct Sequence Spread Spectrum(DSSS) CDMA IS the method used in IS-95 commercial systems

User 1

Code 1

Composite

Time Frequency

+=

Direct Sequence CDMA

User 1 User 2 User 3 User 4 Frequency Hopping CDMA

User 3 User 4 User 1 unused User 2

User 1 User 4 User 3 User 2 unused

Frequency

unused User 1 User 2 User 4 User 3


DSSS Spreading: Time-Domain View

At Originating Site:Input A: User’s Data @ 19,200 bits/secondInput B: Walsh Code #23 @ 1.2288 McpsOutput: Spread spectrum signal

At Destination Site:Input A: Received spread spectrum signalInput B: Walsh Code #23 @ 1.2288 McpsOutput: User’s Data @ 19,200 bits/second just as originally sent Drawn to actual scale and time alignment

via air interface

XORExclusive-OR

Gate

1

1

Input A: Received Signal

Input B: Spreading Code

Output: User’s Original Data

Input A: User’s Data

Input B: Spreading Code

Spread Spectrum Signal

XORExclusive-OR

Gate

Originating Site

Destination Site


Spreading from a Frequency-Domain View

Traditional technologies try to squeeze signal into minimum required bandwidthCDMA uses larger bandwidth but uses resulting processing gain to increase capacity

Spread Spectrum Payoff:Processing Gain

Spread SpectrumTRADITIONAL COMMUNICATIONS SYSTEM

SlowInformation

SentTX

SlowInformationRecovered

RX

NarrowbandSignal

SPREAD-SPECTRUM SYSTEM

FastSpreadingSequence

SlowInformation

SentTX

SlowInformationRecovered

RX

FastSpreadingSequence

WidebandSignal


The CDMA Spread Spectrum Payoff:Would you like a lump-sum, or monthly payments?

Shannon's work suggests that a certain bit rate of information deserves a certain bandwidthIf one CDMA user is carried alone by a CDMA signal, the processing gain is large - roughly 21 db for an 8k vocoder.

• Each doubling of the number of users consumes 3 db of the processing gain

• Somewhere above 32 users, the signal-to-noise ratio becomes undesirable and the ultimate capacity of the sector is reached

Practical CDMA systems restrict the number of users per sector to ensure processing gain remains at usable levels

# Users Processing Gain1 21 db

2 18 db

4 15 db

8 12 db

16 9 db

32 6 db

64…..Uh, Regis, can I justtake the money I've already

won, and go home now?

CDMA Spreading Gain

Consider a user with a 9600 bps vocoder talking on a

CDMA signal 1,228,800 hzwide. The processing gain is 1,228,800/9600 = 128, which

is 21 db. What happens if additional users are added?


CDMA Uses Code Channels

A CDMA signal uses many chips to convey just one bit of information Each user has a unique chip pattern, in effect a code channelTo recover a bit, integrate a large number of chips interpreted by the user’s known code patternOther users’ code patterns appear random and integrate in a random self-canceling fashion, don’t disturb the bit decoding decision being made with the proper code pattern

Building aBuilding aCDMA SignalCDMA Signal

Bitsfrom User’s Vocoder

Symbols

Chips

Forward Error Correction

Coding and Spreading


How a BTS Sector Serves Multiple Users

Σ

if 1 =if 0 =

1

AnalogSummingUsers

QPSK RF

Σ

DemodulatedReceived

CDMA SignalDespreading Sequence(Locally Generated, =0)

matchesopposite

Decision:

Matches!( = 0 )

TimeIntegration

1

Opposite( =1)

+10

-26

Received energy: Correlation

-16

BTS

This figure illustrates the basic technique of CDMA signal generation and recovery.The actual coding process used in IS-95 CDMA includes a few additional layers, as we’ll see in following slides.


Spreading: What we do, we can undo

Sender combines data with a fast spreading sequence, transmits spread data streamReceiver intercepts the stream, uses same spreading sequence to extract original data

ORIGINATING SITE DESTINATION

SpreadingSequence

SpreadingSequence

InputData

RecoveredData

Spread Data Stream


“Shipping and Receiving” via CDMA

Whether in shipping and receiving, or in CDMA, packaging is extremely important!Cargo is placed inside “nested” containers for protection and to allow addressingThe shipper packs in a certain order, and the receiver unpacks in the reverse orderCDMA “containers” are spreading codes

FedE

x

Data Mailer

FedE

x

DataMailer

Shipping Receiving


CDMA’s Nested Spreading Sequences

CDMA combines three different spreading sequences to create unique, robust channelsThe sequences are easy to generate on both sending and receivingends of each link“What we do, we can undo”

SpreadingSequence

ASpreadingSequence

BSpreadingSequence

CSpreadingSequence

CSpreadingSequence

BSpreadingSequence

A

InputDataX

RecoveredDataX

X+A X+A+B X+A+B+C X+A+B X+ASpread-Spectrum Chip Streams

ORIGINATING SITE DESTINATION


One of the CDMA Spreading Sequences:Walsh Codes

64 “Magic” Sequences, each 64 chips longEach Walsh Code is precisely Orthogonal with respect to all other Walsh Codes

• it’s simple to generate the codes, or• they’re small enough to use from ROM

WALSH CODES# ---------------------------------- 64-Chip Sequence ------------------------------------------0 00000000000000000000000000000000000000000000000000000000000000001 01010101010101010101010101010101010101010101010101010101010101012 00110011001100110011001100110011001100110011001100110011001100113 01100110011001100110011001100110011001100110011001100110011001104 00001111000011110000111100001111000011110000111100001111000011115 01011010010110100101101001011010010110100101101001011010010110106 00111100001111000011110000111100001111000011110000111100001111007 01101001011010010110100101101001011010010110100101101001011010018 00000000111111110000000011111111000000001111111100000000111111119 0101010110101010010101011010101001010101101010100101010110101010

10 001100111100110000110011110011000011001111001100001100111100110011 011001101001100101100110100110010110011010011001011001101001100112 000011111111000000001111111100000000111111110000000011111111000013 010110101010010101011010101001010101101010100101010110101010010114 001111001100001100111100110000110011110011000011001111001100001115 011010011001011001101001100101100110100110010110011010011001011016 000000000000000011111111111111110000000000000000111111111111111117 010101010101010110101010101010100101010101010101101010101010101018 001100110011001111001100110011000011001100110011110011001100110019 011001100110011010011001100110010110011001100110100110011001100120 000011110000111111110000111100000000111100001111111100001111000021 010110100101101010100101101001010101101001011010101001011010010122 001111000011110011000011110000110011110000111100110000111100001123 011010010110100110010110100101100110100101101001100101101001011024 000000001111111111111111000000000000000011111111111111110000000025 010101011010101010101010010101010101010110101010101010100101010126 001100111100110011001100001100110011001111001100110011000011001127 011001101001100110011001011001100110011010011001100110010110011028 000011111111000011110000000011110000111111110000111100000000111129 010110101010010110100101010110100101101010100101101001010101101030 001111001100001111000011001111000011110011000011110000110011110031 011010011001011010010110011010010110100110010110100101100110100132 000000000000000000000000000000001111111111111111111111111111111133 010101010101010101010101010101011010101010101010101010101010101034 001100110011001100110011001100111100110011001100110011001100110035 011001100110011001100110011001101001100110011001100110011001100136 000011110000111100001111000011111111000011110000111100001111000037 010110100101101001011010010110101010010110100101101001011010010138 001111000011110000111100001111001100001111000011110000111100001139 011010010110100101101001011010011001011010010110100101101001011040 000000001111111100000000111111111111111100000000111111110000000041 010101011010101001010101101010101010101001010101101010100101010142 001100111100110000110011110011001100110000110011110011000011001143 011001101001100101100110100110011001100101100110100110010110011044 000011111111000000001111111100001111000000001111111100000000111145 010110101010010101011010101001011010010101011010101001010101101046 001111001100001100111100110000111100001100111100110000110011110047 011010011001011001101001100101101001011001101001100101100110100148 000000000000000011111111111111111111111111111111000000000000000049 010101010101010110101010101010101010101010101010010101010101010150 001100110011001111001100110011001100110011001100001100110011001151 011001100110011010011001100110011001100110011001011001100110011052 000011110000111111110000111100001111000011110000000011110000111153 010110100101101010100101101001011010010110100101010110100101101054 001111000011110011000011110000111100001111000011001111000011110055 011010010110100110010110100101101001011010010110011010010110100156 000000001111111111111111000000001111111100000000000000001111111157 010101011010101010101010010101011010101001010101010101011010101058 001100111100110011001100001100111100110000110011001100111100110059 011001101001100110011001011001101001100101100110011001101001100160 000011111111000011110000000011111111000000001111000011111111000061 010110101010010110100101010110101010010101011010010110101010010162 001111001100001111000011001111001100001100111100001111001100001163 0110100110010110100101100110100110010110011010010110100110010110

EXAMPLE:Correlation of Walsh Code #23 with Walsh Code #59

#23 0110100101101001100101101001011001101001011010011001011010010110#59 0110011010011001100110010110011010011001011001100110011010011001Sum 0000111111110000000011111111000011110000000011111111000000001111

Correlation Results: 32 1’s, 32 0’s: Orthogonal!!

Unique Properties:Mutual Orthogonality

In CDMA2000, user data comes at various speeds, and different lengths of walsh codes can exist.See Course 332 for more details on CDMA2000 1xRTT fast data channels and additional Walsh codes.


Other Sequences: Generation & Properties

Other CDMA sequences are generated in shift registersPlain shift register: no fun, sequence = length of registerTapped shift register generates a wild, self-mutating sequence 2N-1 chips long (N=register length)

• Such sequences match if compared in step (no-brainer, any sequence matches itself)

• Such sequences appear approximately orthogonal if compared with themselves not exactly matched in time

• false correlation typically <2%

A Tapped, Summing Shift Register

Sequence repeats every 2N-1 chips,where N is number of cells in register

An Ordinary Shift Register

Sequence repeats every N chips,where N is number of cells in register

A Special Characteristic of SequencesGenerated in Tapped Shift Registers

Compared In-Step: Matches Itself

Complete Correlation: All 0’sSum:Self, in sync:

Sequence:

Compared Shifted: Little Correlation

Practically Orthogonal: Half 1’s, Half 0’sSum:Self, Shifted:

Sequence:


Original IS-95 CDMA PN Scrambling

Short PN Scrambling

New CDMA2000 1x Complex Scrambling

Another CDMA Spreading Sequence:The Short PN Code, used for Scrambling

The short PN code consists of two PN Sequences, I and Q, each 32,768 chips long

• Generated in similar but differently-tapped 15-bit shift registers

• the two sequences scramble the information on the I and Q phase channels

Figures to the right show how one user’s channel is built at the bTS

IQ

32,768 chips long26-2/3 ms.

(75 repetitions in 2 sec.)Σ

RF: cos ωt

RF: sin ωt

user’ssymbols

QPSK-modulated

RFOutput

Same information duplicatedon I and Q

Walsh

I-sequence

Q-sequence

Σ

RF:cos ωt

sin ωtRF

user’ssymbols

QPS

K

Out

put

Walsh

Seria

l to

Para

llel

Σ

Σ

+

DifferentInformationon I and Q

Complex Scrambling

I-sequence

Q-sequence

-+

+


Generating the PN Long Codeat a desired Timing Offset

Every phone and every BTS channel element has a Long Code generator• Long Code State Register makes long code at system reference timing• A Mask Register holds a user-specific unique pattern of bits

Each clock pulse drives the Long Code State Register to its next state• State register and Mask register contents are added in the Summer• Summer contents are modulo-2 added to produce just a single bit output

The output bits are the Long Code, but shifted to the user’s unique offset

LONG CODE STATE REGISTER dynamic contents, zero timing shift

MASK REGISTER unique steady contents cause unique timing shift

SUMMER holds dynamic modulo-2 sum of LC State and Mask registers

Each clock cycle, all the Summer bits are added into a single-bit modulo-2 sum

The shifted Long Code emerges, chip by chip!

clock


Different Masks ProduceDifferent Long PN Offsets

Ordinary mobiles use their ESNs and the Public Long Code Mask to produce their unique Long Code PN offsets

• main ingredient: mobile ESNMobiles needing greater privacy use the Private Long Code Mask

• instead of 32-bit ESN, the mask value is produced from SSD Word B in a calculation similar to authentication

Each BTS sector has an Access Channel where mobiles transmit for registration and call setup

• the Access Channel Long Code Mask includes Access Channel #, Paging Channel #, BTS ID, and Pilot PN

• The BTS transmits all of these parameters on the Paging Channel

fixed AC# PC# BASE_ID PILOT PN

LONG CODE STATE REGISTER

SUMMING REGISTER


SUMMING REGISTER

fixed PERMUTED ESN


SUMMING REGISTER

calculated PRIVATE LONG CODE MASK

ACCESS CHANNEL (IDLE MODE)USING THE ACCESS CHANNEL LONG CODE MASK

TRAFFIC CHANNEL – NORMALUSING THE PUBLIC LONG CODE MASK

TRAFFIC CHANNEL – PRIVATEUSING THE PRIVATE LONG CODE MASK


Section B

IS-95 CDMA Forward and Reverse Channels

IS-95 CDMA Forward and Reverse Channels


How a BTS Builds the Forward Code Channels

BSC orAccess Manager

BTS (1 sector)

FECWalsh #1

Sync FECWalsh #32

FECWalsh #0

FECWalsh #12

FECWalsh #27

FECWalsh #44

Pilot

Paging

Vocoder

Vocoder

Vocoder

Vocoder

more more

Short PN CodePN Offset 246

Trans-mitter,

Sector X

Switch

more

a Channel Element

A Forward Channel is identified by:its CDMA RF carrier Frequencythe unique Short Code PN Offset of the sectorthe unique Walsh Code of the user

FECWalsh #23

ΣQ

ΣI

x

x+

cos ωt

sin ωt

I Q


Functions of the CDMA Forward Channels

PILOT: WALSH CODE 0• The Pilot is a “structural beacon” which

does not contain a character stream. It is a timing source used in system acquisition and as a measurement device during handoffs

SYNC: WALSH CODE 32• This carries a data stream of system

identification and parameter information used by mobiles during system acquisition

PAGING: WALSH CODES 1 up to 7• There can be from one to seven paging

channels as determined by capacity needs. They carry pages, system parameters information, and call setup orders

TRAFFIC: any remaining WALSH codes• The traffic channels are assigned to

individual users to carry call traffic. All remaining Walsh codes are available, subject to overall capacity limited by noise

Pilot Walsh 0

Walsh 19

Paging Walsh 1Walsh 6

Walsh 11

Walsh 20Sync Walsh 32

Walsh 42

Walsh 37Walsh 41

Walsh 56Walsh 60

Walsh 55


Code Channels in the Reverse DirectionBSC, CBSC,Access

Manager

Switch BTS (1 sector)

Channel Element

Access Channels

Vocoder

Vocoder

Vocoder

Vocoder

more more

Receiver,Sector X

A Reverse Channel is identified by:its CDMA RF carrier Frequencythe unique Long Code PN Offsetof the individual handset

Channel Element

Channel Element

Channel Element

Long Code Gen

Long Code Gen

Long Code Gen

Long Code Gen

more

a Channel Element

LongCodeoffset Long

Codeoffset Long

Codeoffset

LongCodeoffset

LongCodeoffset

LongCodeoffset

Channel Element

Long Code Gen


REG

1-800242

4444

BTS

Although a sector can have up to seven paging channels, and each paging channel can have up to 32 access channels, nearly all systems today use only one paging

channel per sector and only one access channel per paging channel.

Functions of the CDMA Reverse ChannelsThere are two types of CDMA Reverse Channels:

TRAFFIC CHANNELS are used by individual users during their actual calls to transmit traffic to the BTS

• a reverse traffic channel is really just a user-specific public or private Long Code mask

• there are as many reverse Traffic Channels as there are CDMA phones in the world!

ACCESS CHANNELS are used by mobiles not yet in a call to transmit registration requests, call setup requests, page responses, order responses, and other signaling information

• an access channel is really just a public long code offset unique to the BTS sector

• Access channels are paired to Paging Channels. Each paging channel can have up to 32 access channels.


Summing Up Original IS-95 CDMA Channels

Existing IS-95A/JStd-008 CDMA uses the channels above for call setup and traffic channels – all call processing transactions use these channels

• traffic channels are 9600 bps (rate set 1) or 14400 bps (rate set 2)IS-2000 CDMA is backward-compatible with IS-95, but offers additional radio configurations and additional kinds of possible channels

• These additional modes are called Radio Configurations• IS-95 Rate Set 1 and 2 are IS-2000 Radio Configurations 1 & 2

FORWARD CHANNELS

BTS

W0: PILOT

W32: SYNC

W1: PAGING

Wn: TRAFFIC

REVERSE CHANNELS

ACCESS

TRAFFIC


The Channels at Phase One 1xRTT Launch

CDMA2000 1xRTT has a rich variety of traffic channels for voice and fast dateThere are also optional additional control channels for more effective operation

Includes PowerControl Subchannel

Enhanced Access Channel

CommonControl Channel

DedicatedControl Channel

Reverse FundamentalChannel (IS95B comp.)

Reverse Supplemental Channel

Access Channel(IS-95B compatible)

R-TRAFFIC

REVERSE CHANNELS

R-Pilot

R-CCCH

R-DCCH

R-FCH

R-SCH

R-EACH

1

1

0 or 1

0 or 1

0 to 2

R-ACH or

1

BTS

Dedicated Control Channel

Same coding as IS-95B,Backward compatible



Broadcast Channel

Quick Paging Channel

Common Power Control Channel

Common Assignment Channel

Common Control Channels

Forward Traffic Channels

Fundamental Channel

SupplementalChannels IS-95B only

SupplementalChannels RC3,4,5

F-TRAFFIC

FORWARD CHANNELS

F-Pilot

F-Sync

PAGING

F-BCH

F-QPCH

F-CPCCH

F-CACH

F-CCCH

F-DCCH

1

1

1 to 7

0 to 8

0 to 3

0 to 4

0 to 7

0 to 7

0 or 1

F-FCH

F-SCH

F-SCH

1

0 to 7

0 to 2

IS-95B only

Users:Users:0 to many0 to many

How manyPossible:

See Course 332 for more details.


Spreading Rates & Radio ConfigurationsRadio

Configuration

RC1

RC2

RC3

RC4

RC5

RC6

RC7

RC8

RC9

SpreadingRate

SR11xRTT1 carrier1.2288MCPS

SR33xRTT

Fwd:3 carriers

1.2288MCPSRev:

3.6864MCPS

Forward Link

Required. IS-95B CompatibleNo CDMA2000 coding features

Compatible with IS-95B RS2No CDMA2000 coding features

Quarter-rate convolutional or Turbo Coding, base rate 9600

Half-rate convolutional or Turbo Coding, base rate 9600

Quarter-rate convolutional or Turbo Coding, base rate 14400

1/6 rate convolutionalor Turbo coding, base rate 9600

Required. 1/3 rate convolutionalor Turbo coding, base rate 9600

¼ or 1/3 rate convolutional orTurbo coding, base rate 14400

½ or 1/3 rate convolutional or Turbo encoder, base rate 14400

DataRates

9600

14400

9600153600

9600307200

14400230400

9600307200

9600614400

14400460800

144001036800

Quarter rate convolutional or Turbo coding; Half rate convolutional or Turbo coding;base rate 9600

Quarter rate convolutional or Turbo Coding, base rate 14400

Required. ¼ or 1/3 convolutionalor Turbo coding, base rate 9600

¼ or ½ convolutional or Turboencoding, base rate 14400

Required. IS-95B CompatibleNo CDMA2000 coding features

Compatible with IS-95B RS2No CDMA2000 coding features

RC1

RC2

RC3

RC4

RC5

RC6

9600

14400

9600

153600

307200

14400230400

9600

307200

614400

14400

460800

1036800

Reverse LinkDataRates

RadioConfiguration


SR1, RC1 9,600 bps F-FCH (IS-95-Compatible)

Same sym

bols go on both I and Q!

PowerControl

Puncturing

Data Bits

8.6 kbps

+CRC &Tail bits

9.6 kbps

1/2 rateConv Encoder Interleaver

User Long Code Mask

Long CodeGenerator

Long CodeDecimator

Power CtrlDecimator

PCPunc

Pwr CtrlBits

GainGain

19.2 ksps

I Short Code

QShort Code

FIRLPF

FIRLPF

II

QQ

OrthogonalSpreading

1228.8 kbps /W

800 bps

800 bps

19.2 ksps

1228.8 kcps

1228.8 kcps

SymbolRepetition Σ

ΣBTS Walsh 64Generator

1228.8 kcps


SR1, RC2 14,400 bps F-FCH (IS-95-Compatible)

Same sym

bols go on both I and Q!

PowerControl

Puncturing

Data Bits

13.35 kbps

+CRC &Tail bits

14.4 kbps


User Long Code Mask

Long CodeGenerator

Long CodeDecimator

Power CtrlDecimator

PCPunc

Pwr CtrlBits

GainGain

19.2 ksps

I Short Code

QShort Code

FIRLPF

FIRLPF

II

QQ

OrthogonalSpreading

1228.8 kbps /W

800 bps

800 bps

19.2 ksps

1228.8 kcps

1228.8 kcps

SymbolRepetition

SymbolPuncturing

28.8 ksps

2 of 6

Σ

ΣBTS Walsh 64Generator

1228.8 kcps


SR1, RC3 F-FCH (9,600 bps)

The stream of symbols is divided into two parts: one on logical I and one on logical Q

Complex scrambling ensures that the

physical I and Q phase planes contain equal

amplitudes at all times. This minimizes the

peak-to-average power levels in the signal.

PowerControl

PuncturingFull RateData Bits8.6 kbps

+CRC &Tail bits

9.6 kbps


User Long Code Mask

Long CodeGenerator

Long CodeDecimator

Power CtrlDecimator

PCPunc

Pwr CtrlBits

GainGain

Serial toParallel

Walsh 64Generator

I

Q

38.4 ksps

I Short Code

QShort Code

FIRLPF

FIRLPF

I

II

Q QQ

OrthogonalSpreading

ComplexScrambling

+

-

+

+Power control informationmay be carried as shown

or on the F-DCCH

1228.8 kbps /W/2

800 bps

800 bps

19.2 ksps

19.2 ksps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

38.4 ksps

Σ

ΣBTS

Doubled power efficiency, but still only 64 walsh codes


SR1, RC4 F-FCH (9,600 bps)






PowerControl

PuncturingFull RateData Bits8.6 kbps

+CRC &Tail bits

9.6 kbps


User Long Code Mask

Long CodeGenerator

Long CodeDecimator

Power CtrlDecimator

PCPunc

Pwr CtrlBits

GainGain

Serial toParallel

Walsh 128Generator

I

Q

19.2 ksps

I Short Code

QShort Code

FIRLPF

FIRLPF

I

II

Q QQ

OrthogonalSpreading

ComplexScrambling

+

-

+

+Power control informationmay be carried as shown

or on the F-DCCH

1228.8 kbps /W/2

800 bps

800 bps

9.6 ksps

9.6 ksps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

19.2 ksps

Σ

ΣBTS

Double the walsh codes, but no better power efficiency.


SR1, RC3 F-SCH (153,600 bps)






PayloadData Bits

152.4 kbps

+CRC &Tail bits

153.6 kbps


User Long Code Mask

Long CodeGenerator

Long CodeDecimator

GainSerial toParallel

Walsh 4Generator

I

Q

614.4 kspsI

Short Code

QShort Code

FIRLPF

FIRLPF

I

II

Q QQ

OrthogonalSpreading

ComplexScrambling

+

-

+

+

1228.8 kbps /W/2

307.2 ksps

307.2 ksps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

614.4 ksps

614.4 ksps

Σ

ΣBTS


SR1, RC4 F-SCH (307,200 bps)






PayloadData Bits

304.8 kbps

+CRC &Tail bits

307.2 kbps


User Long Code Mask

Long CodeGenerator

Long CodeDecimator

GainSerial toParallel

Walsh 4Generator

I

Q

614.4 kspsI

Short Code

QShort Code

FIRLPF

FIRLPF

I

II

Q QQ

OrthogonalSpreading

ComplexScrambling

+

-

+

+

1228.8 kbps /W/2

307.2 ksps

307.2 ksps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

1228.8 kcps

614.4 ksps

614.4 ksps

Σ

ΣBTS


The Famous Walsh Codes from IS-95 Days

64 “Magic” Sequences, each 64 chips longEach Walsh Code is precisely Orthogonal with respect to all other Walsh Codes and their opposites too!

• it’s simple to generate the codes, or• they’re small enough to use from ROM


10 001100111100110000110011110011000011001111001100001100111100110011 011001101001100101100110100110010110011010011001011001101001100112 000011111111000000001111111100000000111111110000000011111111000013 010110101010010101011010101001010101101010100101010110101010010114 001111001100001100111100110000110011110011000011001111001100001115 011010011001011001101001100101100110100110010110011010011001011016 000000000000000011111111111111110000000000000000111111111111111117 010101010101010110101010101010100101010101010101101010101010101018 001100110011001111001100110011000011001100110011110011001100110019 011001100110011010011001100110010110011001100110100110011001100120 000011110000111111110000111100000000111100001111111100001111000021 010110100101101010100101101001010101101001011010101001011010010122 001111000011110011000011110000110011110000111100110000111100001123 011010010110100110010110100101100110100101101001100101101001011024 000000001111111111111111000000000000000011111111111111110000000025 010101011010101010101010010101010101010110101010101010100101010126 001100111100110011001100001100110011001111001100110011000011001127 011001101001100110011001011001100110011010011001100110010110011028 000011111111000011110000000011110000111111110000111100000000111129 010110101010010110100101010110100101101010100101101001010101101030 001111001100001111000011001111000011110011000011110000110011110031 011010011001011010010110011010010110100110010110100101100110100132 000000000000000000000000000000001111111111111111111111111111111133 010101010101010101010101010101011010101010101010101010101010101034 001100110011001100110011001100111100110011001100110011001100110035 011001100110011001100110011001101001100110011001100110011001100136 000011110000111100001111000011111111000011110000111100001111000037 010110100101101001011010010110101010010110100101101001011010010138 001111000011110000111100001111001100001111000011110000111100001139 011010010110100101101001011010011001011010010110100101101001011040 000000001111111100000000111111111111111100000000111111110000000041 010101011010101001010101101010101010101001010101101010100101010142 001100111100110000110011110011001100110000110011110011000011001143 011001101001100101100110100110011001100101100110100110010110011044 000011111111000000001111111100001111000000001111111100000000111145 010110101010010101011010101001011010010101011010101001010101101046 001111001100001100111100110000111100001100111100110000110011110047 011010011001011001101001100101101001011001101001100101100110100148 000000000000000011111111111111111111111111111111000000000000000049 010101010101010110101010101010101010101010101010010101010101010150 001100110011001111001100110011001100110011001100001100110011001151 011001100110011010011001100110011001100110011001011001100110011052 000011110000111111110000111100001111000011110000000011110000111153 010110100101101010100101101001011010010110100101010110100101101054 001111000011110011000011110000111100001111000011001111000011110055 011010010110100110010110100101101001011010010110011010010110100156 000000001111111111111111000000001111111100000000000000001111111157 010101011010101010101010010101011010101001010101010101011010101058 001100111100110011001100001100111100110000110011001100111100110059 011001101001100110011001011001101001100101100110011001101001100160 000011111111000011110000000011111111000000001111000011111111000061 010110101010010110100101010110101010010101011010010110101010010162 001111001100001111000011001111001100001100111100001111001100001163 0110100110010110100101100110100110010110011010010110100110010110

EXAMPLE:Correlation of Walsh Code #23 with Walsh Code #59

#23 0110100101101001100101101001011001101001011010011001011010010110#59 0110011010011001100110010110011010011001011001100110011010011001Sum 0000111111110000000011111111000011110000000011111111000000001111

Correlation Results: 32 1’s, 32 0’s: Orthogonal!!

Unique Properties:Mutual Orthogonality


IS-95 Busy SectorSnapshot of Walsh Usage


Walsh Codes in 1xRTT

Data Rates are different, butChip Rates must stay the same!

2G VOICE AND DATAOne Symbol of Information

64 chips of Walsh Code1,228,800 walsh chips/second

19,200 symbols/secondDATA

SYMBOLS

WALSHCODE

3G 153.6 kb/s DATA One Symbol of Fast Data

4 Chips of Walsh Code 1,228,800 walsh chips/second

307,200 symbols/secondDATA

SYMBOLS

WALSHCODE


Families of the Walsh Codes

All Walsh codes can be built to any size from a single zero by replicating and invertingAll Walsh matrixes are square -- same number of codes and number of chips per code


10 001100111100110000110011110011000011001111001100001100111100110011 011001101001100101100110100110010110011010011001011001101001100112 000011111111000000001111111100000000111111110000000011111111000013 010110101010010101011010101001010101101010100101010110101010010114 001111001100001100111100110000110011110011000011001111001100001115 011010011001011001101001100101100110100110010110011010011001011016 000000000000000011111111111111110000000000000000111111111111111117 010101010101010110101010101010100101010101010101101010101010101018 001100110011001111001100110011000011001100110011110011001100110019 011001100110011010011001100110010110011001100110100110011001100120 000011110000111111110000111100000000111100001111111100001111000021 010110100101101010100101101001010101101001011010101001011010010122 001111000011110011000011110000110011110000111100110000111100001123 011010010110100110010110100101100110100101101001100101101001011024 000000001111111111111111000000000000000011111111111111110000000025 010101011010101010101010010101010101010110101010101010100101010126 001100111100110011001100001100110011001111001100110011000011001127 011001101001100110011001011001100110011010011001100110010110011028 000011111111000011110000000011110000111111110000111100000000111129 010110101010010110100101010110100101101010100101101001010101101030 001111001100001111000011001111000011110011000011110000110011110031 011010011001011010010110011010010110100110010110100101100110100132 000000000000000000000000000000001111111111111111111111111111111133 010101010101010101010101010101011010101010101010101010101010101034 001100110011001100110011001100111100110011001100110011001100110035 011001100110011001100110011001101001100110011001100110011001100136 000011110000111100001111000011111111000011110000111100001111000037 010110100101101001011010010110101010010110100101101001011010010138 001111000011110000111100001111001100001111000011110000111100001139 011010010110100101101001011010011001011010010110100101101001011040 000000001111111100000000111111111111111100000000111111110000000041 010101011010101001010101101010101010101001010101101010100101010142 001100111100110000110011110011001100110000110011110011000011001143 011001101001100101100110100110011001100101100110100110010110011044 000011111111000000001111111100001111000000001111111100000000111145 010110101010010101011010101001011010010101011010101001010101101046 001111001100001100111100110000111100001100111100110000110011110047 011010011001011001101001100101101001011001101001100101100110100148 000000000000000011111111111111111111111111111111000000000000000049 010101010101010110101010101010101010101010101010010101010101010150 001100110011001111001100110011001100110011001100001100110011001151 011001100110011010011001100110011001100110011001011001100110011052 000011110000111111110000111100001111000011110000000011110000111153 010110100101101010100101101001011010010110100101010110100101101054 001111000011110011000011110000111100001111000011001111000011110055 011010010110100110010110100101101001011010010110011010010110100156 000000001111111111111111000000001111111100000000000000001111111157 010101011010101010101010010101011010101001010101010101011010101058 001100111100110011001100001100111100110000110011001100111100110059 011001101001100110011001011001101001100101100110011001101001100160 000011111111000011110000000011111111000000001111000011111111000061 010110101010010110100101010110101010010101011010010110101010010162 001111001100001111000011001111001100001100111100001111001100001163 0110100110010110100101100110100110010110011010010110100110010110

WALSH CODES# ----------- 32-Chip Sequence -------------0 000000000000000000000000000000001 010101010101010101010101010101012 001100110011001100110011001100113 011001100110011001100110011001104 000011110000111100001111000011115 010110100101101001011010010110106 001111000011110000111100001111007 011010010110100101101001011010018 000000001111111100000000111111119 01010101101010100101010110101010

10 0011001111001100001100111100110011 0110011010011001011001101001100112 0000111111110000000011111111000013 0101101010100101010110101010010114 0011110011000011001111001100001115 0110100110010110011010011001011016 0000000000000000111111111111111117 0101010101010101101010101010101018 0011001100110011110011001100110019 0110011001100110100110011001100120 0000111100001111111100001111000021 0101101001011010101001011010010122 0011110000111100110000111100001123 0110100101101001100101101001011024 0000000011111111111111110000000025 0101010110101010101010100101010126 0011001111001100110011000011001127 0110011010011001100110010110011028 0000111111110000111100000000111129 0101101010100101101001010101101030 0011110011000011110000110011110031 01101001100101101001011001101001

WALSH# ---- 16-Chips -------0 00000000000000001 01010101010101012 00110011001100113 01100110011001104 00001111000011115 01011010010110106 00111100001111007 01101001011010018 00000000111111119 0101010110101010

10 001100111100110011 011001101001100112 000011111111000013 010110101010010114 001111001100001115 0110100110010110

WALSH# 8-Chips 0 000000001 010101012 001100113 011001104 000011115 010110106 001111007 01101001

WALSH# 4-Chips 0 00001 01012 00113 0110

WALSH# 2-Chips 0 001 01

WALSH# 1-Chip0 0

64x64

32x32

16x16

8x84x42x2

Walsh Level MappingThe Walsh Codes shown here are in logical state values 0 and 1.Walsh Codes also can exist as physical bipolar signals. Logical zero is the signal value +1 and Logical 1 is the signal value -1.Mapping: Logical 0,1 > +1, -1 Physical

Walsh Code NamesW1232 = “Walsh Code #12, 32 chips long.”


Walsh Code Trees and Interdependencies

Entire Walsh matrices can be built by replicating and inverting -- Individual Walsh codes can also be expanded in the same way.CDMA adds each symbol of information to one complete Walsh codeFaster symbol rates therefore require shorter Walsh codesIf a short Walsh code is chosen to carry a fast data channel, that walsh code and all its replicative descendants are compromised and cannot be reused to carry other signalsTherefore, the supply of available Walsh codes on a sector diminishes greatly while a fast data channel is being transmitted!CDMA2000 Base stations can dip into a supply of quasi-orthogonal codes if needed to permit additional channels during times of heavy loading

0110

1001

0110

0110

0110

0110 0110 0110 0110

0110 0110 1001 1001

10010110 10010110

10010110 1001 011010010110 1001 0110 10010110 1001 0110

10010110 1001 0110 1001 0110 10010110

10010110 10010110

10010110 10010110

10010110 10010110

100101101001 0110

0110 0110 1001 1001

0110 0110 1001 1001 0110 0110 1001 1001

0110 01101001 1001

0110 0110 0110 0110 0110 0110 0110 0110

0110 0110 0110 0110 1001 1001 1001 1001

W34

W38

W78

W716

W1116

W316

W1516

W732

W2332

W1532

W3132

W2732

W1132

W1932

W332 W364

W3564

W1964

W5164

W1164

W4364

W2764

W5964

W764

W3964

W2364

W5564

W1564

W4764

W3164

W6364


Walsh Code Families and ExclusionsConsider a forward link supplemental channel being transmitted with a data rate of 307,200 symbols/second

• Each symbol will occupy 4 chips at the 1x rate of 1,228,800 c/s.

• A 4-chip walsh code will be used for this channel

If Walsh Code #3 (4 chips) is chosen for this channel:

• Use of W34 will preclude other usage of the following 64-chip walsh codes:

• 3, 35, 19, 51, 11, 43, 27, 59, 7, 39, 23, 55, 15, 47, 31, 63 -- all forbidden!

• 16 codes are tied up since the data is being sent at 16 times the rate of conventional 64-chip walsh codes

The BTS controller managing this sector must track the precluded walsh codes and ensure they aren’t assigned


10 001100111100110000110011110011000011001111001100001100111100110011 011001101001100101100110100110010110011010011001011001101001100112 000011111111000000001111111100000000111111110000000011111111000013 010110101010010101011010101001010101101010100101010110101010010114 001111001100001100111100110000110011110011000011001111001100001115 011010011001011001101001100101100110100110010110011010011001011016 000000000000000011111111111111110000000000000000111111111111111117 010101010101010110101010101010100101010101010101101010101010101018 001100110011001111001100110011000011001100110011110011001100110019 011001100110011010011001100110010110011001100110100110011001100120 000011110000111111110000111100000000111100001111111100001111000021 010110100101101010100101101001010101101001011010101001011010010122 001111000011110011000011110000110011110000111100110000111100001123 011010010110100110010110100101100110100101101001100101101001011024 000000001111111111111111000000000000000011111111111111110000000025 010101011010101010101010010101010101010110101010101010100101010126 001100111100110011001100001100110011001111001100110011000011001127 011001101001100110011001011001100110011010011001100110010110011028 000011111111000011110000000011110000111111110000111100000000111129 010110101010010110100101010110100101101010100101101001010101101030 001111001100001111000011001111000011110011000011110000110011110031 011010011001011010010110011010010110100110010110100101100110100132 000000000000000000000000000000001111111111111111111111111111111133 010101010101010101010101010101011010101010101010101010101010101034 001100110011001100110011001100111100110011001100110011001100110035 011001100110011001100110011001101001100110011001100110011001100136 000011110000111100001111000011111111000011110000111100001111000037 010110100101101001011010010110101010010110100101101001011010010138 001111000011110000111100001111001100001111000011110000111100001139 011010010110100101101001011010011001011010010110100101101001011040 000000001111111100000000111111111111111100000000111111110000000041 010101011010101001010101101010101010101001010101101010100101010142 001100111100110000110011110011001100110000110011110011000011001143 011001101001100101100110100110011001100101100110100110010110011044 000011111111000000001111111100001111000000001111111100000000111145 010110101010010101011010101001011010010101011010101001010101101046 001111001100001100111100110000111100001100111100110000110011110047 011010011001011001101001100101101001011001101001100101100110100148 000000000000000011111111111111111111111111111111000000000000000049 010101010101010110101010101010101010101010101010010101010101010150 001100110011001111001100110011001100110011001100001100110011001151 011001100110011010011001100110011001100110011001011001100110011052 000011110000111111110000111100001111000011110000000011110000111153 010110100101101010100101101001011010010110100101010110100101101054 001111000011110011000011110000111100001111000011001111000011110055 011010010110100110010110100101101001011010010110011010010110100156 000000001111111111111111000000001111111100000000000000001111111157 010101011010101010101010010101011010101001010101010101011010101058 001100111100110011001100001100111100110000110011001100111100110059 011001101001100110011001011001101001100101100110011001101001100160 000011111111000011110000000011111111000000001111000011111111000061 010110101010010110100101010110101010010101011010010110101010010162 001111001100001111000011001111001100001100111100001111001100001163 0110100110010110100101100110100110010110011010010110100110010110

0110W34

Which Walsh Codes get tied up by another?Wxxyyties up every YYth Walsh Code starting with #XX.


Forward Link Walsh Codes in 1xRTT

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

Paging 7

Paging 3

Paging 5

Paging

PCH

6

PCH

2

PCH

4

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

76.8ksps

This way of arranging Walsh codes is called “bit reversal order”. It shows each Walsh code’s parents and children. Remember, we cannot use any Walsh code if

another Walsh code directly above it or below it is in use.


IS-95 Today Typical Usage:Pilot, Paging Sync, up to 61 Voice Users

But if the users are highly mobile, forward power may exhaust at typically 30-40 users.In fixed-wireless or “stadium” type applications, all walsh codes may be usable.

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

19.2k19.2kS

yncPilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k ???????Traffic Channels

Voice or Data9.6k/14.4k

76.8ksps

38.4k


Mixed IS-95 / 1xRTT RC3 Voice Typical Usage: Pilot, Paging Sync, up to 61 Voice Users

FCHs of 1xRTT RC3 users consume less power, so more total users are possible than inIS-95. The BTS will probably have enough forward power to carry calls on all 61 walsh codes!

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

19.2k19.2kS

yncPilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

F-FCHs mixedRC1,2,3 Voice

76.8ksps

??


A Not-too-Desirable 1xRTT RC3 State:1 F-SCH, 27 Voice IS-95/1xRTT RC3 Users, 16 Active Data Users

The data users can rapidly share the one F-SCH for 153 kb/s peak, ~9Kb/s avg. user rates.But so many active data users F-FCHs consume a lot of capacity, reduce number of voice users!

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

F-SCH 153K RC3

F-FCHs 9.6kRC3 Data

F-FCHs 9.6kRC3 Voice


76.8kspsWasteful, since many of these users are

not actively sending or receiving data


A Better 1xRTT RC3 BTS Dynamic State:1 F-SCH, 39 IS-95/1xRTT RC3 Voice Users, 4 Active+12 Dormant Data Users

But it takes seconds to move various data users from Dormant to Active!Data users will get 153 kb/s peak, ~9 kb/s average, but latency will be high.

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k




F-FCH

sD

ata

F-SCH 153K RC3

76.8ksps


Slightly Improved 1xRTT RC3 BTS Dynamic State:1 F-SCH, 37 IS-95/1xRTT RC3 Voice Users, 4 Active+12 Control-Hold Data Users

Instead of sending 16 data users to Dormant State, let them time-share 2 F-DCCH for Control Hold state. Data users will get 153 kb/s peak, ~9 kb/s average, good latency.

Not yet available or implemented.

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k




F-FCH

sD

ata

F-SCH 153K RC3

F-DC

CH

s76.8ksps


Heavy Data 1xRTT RC3 BTS Dynamic State:2 F-SCH, 21 IS-95/1xRTT RC3 Voice Users, 4 Active+12 Control-Hold Data Users

16 data users time-share 2 F-DCCH for Control Hold state. Data users get 38.4, 76.4,or 153.6 kb/s peak, ~19 kb/s average, good latency. But only 21 voice users!

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k



F-FCH

sD

ata

F-SCH 153K RC3

F-DC

CH

s

F-SCH 153K RC3

76.8ksps


1xRTT Busy SectorWalsh Code Usage


1xRTT RC3 BTS with Different User Data Rates:3 F-SCH, 37 IS-95/1xRTT RC3 Voice Users, 4 Active+12 Control-Hold RC3 Data Users

16 data users time-share 2 F-DCCH for Control Hold state. Data users get 38.4, 76.4, or 153.6 kb/s peak, ~9 kb/s average, good latency.

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k




F-FCH

sD

ataF-SCH

76K RC3F-D

CC

Hs

F-SCH

38K

F-SCH

38K76.8ksps


1xRTT RC4 Voice Only:Pilot, Paging Sync, up to 118 Voice Users

Wow! 118 users! But RC4 users F-FCHs consume as much power as old IS-95 calls.BTS may run out of forward power before the all walsh codes are used.

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

F-FCHs 9.6k RC4 Voice



F-FCHs 9.6k RC4 Voice???????

76.8ksps


1xRTT RC4 Voice and Data:1 F-SCH, 80 1xRTT RC4 Voice Users, 4 Active+12 Control-Hold RC4 Data Users

16 data users time-share 2 F-DCCH for Control Hold state. Data users will get 38.4,76.4, 153.6 or 307.2 kb/s peak, ~19 kb/s average, good latency. But fwd power may exhaust!

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

Sync

Pilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

F-SCH 307K RC4



F-FCHs 9.6k RC4 Voice????

F-FCH

sF-D

CC

Hs

76.8ksps


Mature 1xRTT Mixed-Mode Voice and Data:1 RC3/RC4 Shared F-SCH, 20 RC3 Voice Users, 38 RC4 Voice Users,

3 Active+12 Control-Hold RC3 and RC4 Data Users16 data users time-share 2 F-DCCH for Control Hold state. Data users will get

38.4, 76.4, 153.6 or 307.2 kb/s peak, ~9 or 19 kb/s average, good latency. Fwd power tight!

9,6004,8002,400sps

307200sps

153,600sps

76,800sps

38,400sps

19,200sps

Code#

Code#

Code#

Code#

Code#

Code#

128 chips4 chips

8 chips16 chips

32 chips64 chips

Code#

Code#

Code#

Code#

Code#

Code#

73516240

3120

1571131359114610212480

311523727111932913215259171301422626101822812204248160

54

12763953111147791511955872310339717123599127107437511115518319993567312561932910945771311753852110137695121578925105417391134981189733651126629430110467814118862210238706122589026106427410114508218983466212460922810844761211652842010036684120568824104407281124880169632640

0 32 16 48 8 40 24 56 4 36 20 52 12 44 28 60 2 34 18 50 10 42 26 58 6 38 22 54 14 46 30 62 1 33 17 49 9 41 25 57 5 37 21 53 13 45 29 61 3 35 19 51 11 43 27 59 7 39 23 55 15 47 31 63

QPC

HQ

PCH

QPC

HTX

Div PIlot

19.2k

19.2k

19.2k

19.2k

Paging

19.2k

19.2k

19.2k

19.2k19.2kS

yncPilot

38.4k

38.4k38.4k

38.4k

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

76.8ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH153.6 ksps

F-SCH307.2 ksps

F-SCH307.2 ksps

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

38.4k

19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k19.2k19.2k19.2k

19.2k19.2k19.2k19.2k

F-SCH 153K RC3or

F-SCH 307K RC4







F-FCH

sF-D

CC

Hs

Or Combinations

????

76.8ksps


Section C

Operational DetailsVocoding, Multiplexing, Power Control

Operational DetailsVocoding, Multiplexing, Power Control


Variable Rate Vocoding & Multiplexing

Vocoders compress speech, reduce bit rate, greatly increasing capacityCDMA uses a superior Variable Rate Vocoder

• full rate during speech• low rates in speech pauses• increased capacity• more natural sound

Voice, signaling, and user secondary data may be mixed in CDMA frames

DSP QCELP VOCODER

Codebook

PitchFilter

FormantFilter

Coded Result Feed-back

20ms Sample

Frame Sizesbits

Full Rate Frame1/2 Rate Frame1/4 Rt.1/824/36

48/7296/144

192/288

Frame Contents: can be a mixture ofPrimaryTraffic(Voice or

data)

Signaling(System

Messaging)

Secondary(On-Air

activation, etc)


How Power Control Works

800 Power Control Bits per second!

TX RF Digital

BTSBSC

Eb/NoSetpoint

Bad FER?Raise Setpoint

Stronger thansetpoint?

OpenLoop Closed

LoopReverse Link

REVERSE LINK POWER ADJUSTMENT

RX RF Digital

IS-95, 1xRTTALL SAME METHOD

TXPO = -(RXdbm) -C + TXGA

MOBILE

FEI Bits Mark Bad Frames Received

BSCSyncPilot

Paging

Short PN

Trans-mitter,

Sector XΣ I QUser 1User 2User 3

Voc-oder

BTS (1 sector)

Forward Link

FORWARD LINK POWER ADJUSTMENT

Selec-tor

MOBILE

Eb/NoSetpoint

FEI Bits

Bad FrameCounterPMRM POWER MEAS. REPORT MSG “2 bad in last 4, Help!!”

POWER CONTROL BITSTREAM RIDING ON MOBILE PILOT

DGU

IS-95 RS1Method

IS-95 RS2Method1xRTTMethod


Details of Reverse Link Power Control

TXPO Handset Transmit Power• Actual RF power output of the

handset transmitter, including combined effects of open loop power control from receiver AGC and closed loop power control by BTS

• can’t exceed handset’s maximum (typ. +23 dBm)

TXGA Transmit Gain Adjust• Sum of all closed-loop

power control commands from the BTS since the beginning of this call

TXPODUP x ≈ IF

LNA

Subscriber Handset

R

R

R

S

Rake

Σ ViterbiDecoder

Vocoder

∼

FECOrthMod

Long PN

xx

xIF Mod

I

Q

x ~LO Open Loop

LO

Closed Loop Pwr Ctrl

IF

Receiver>>

<<Transmitter

PA

BTS

Typical TXPO:+23 dBm in a coverage hole0 dBm near middle of cell-50 dBm up close to BTS

0 dB

-10 dB

-20 dB

Typical Transmit Gain Adjust

Time, Seconds

TXPO = -(RXdbm) -C + TXGAC = +73 for 800 MHz. systems= +76 for 1900 MHz. systems


CDMA Network ArchitectureCDMA Network Architecture


BASE STATIONCONTROLLER

SUPPORTFUNCTIONS

BASE STATIONS

Mobile TelephoneSwitching Office

PSTNLocal CarriersLong Distance

CarriersATM Link

to other CDMANetworks(Future)

Structure of a Typical CDMA System

Voice Mail System SWITCH

HLR Home Location Register(subscriber database)


Voice Call Path through the CDMA Network

BSC-BSMMTX BTS

Ch. Card ACC

Σα

Σβ

Σχ

TFU1

GPSRBSM

CDSU

CDSU

SBSVocodersSelectors

CDSU

CDSU

CDSU

CDSU

CDSU

CMSLM

LPP LPPENET

DTCs

DMS-BUS

TxcvrA

TxcvrB

TxcvrC

RFFEA

RFFEB

RFFEC

TFU

GPSR

GPS GPS

IOC

PSTN

CDSU DISCOCDSU

DISCO 1

DISCO 2

DS0 in T1Packets

ChipsRFChannel

ElementVocoder,Selector


1x Data Call Path through the CDMA Network

BSC-BSMMTX BTS

Ch. Card ACC

Σα

Σβ

Σχ

TFU1

GPSRBSM

CDSU

CDSU


CDSU

CDSU

CDSU

CDSU

CDSU

CMSLM

LPP LPPENET

DTCs

DMS-BUS

TxcvrA

TxcvrB

TxcvrC

RFFEA

RFFEB

RFFEC

TFU

GPSR

GPS GPS

IOC

PSTN

CDSU DISCOCDSU

DISCO 1

DISCO 2Packets

ChipsRFChannel

Elements(FCH, SCH)

Selector

PDSNInternetVPNs

R-PInterface


Section D

CDMA Messages and Call ProcessingCDMA Messages and Call Processing


Messages in CDMA

In CDMA, most call processing events are driven by messagesSome CDMA channels exist for the sole purpose of carrying messages; they never carry user’s voice traffic

• Sync Channel (a forward channel)• Paging Channel (a forward channel)• Access Channel (a reverse channel)• On these channels, there are only messages, continuously all

of the timeSome CDMA channels exist just to carry user traffic

• Forward Traffic Channel• Reverse Traffic Channel• On these channels, most of the time is filled with traffic and

messages are sent only when there is something to doAll CDMA messages have very similar structure, regardless of thechannel on which they are sent


How CDMA Messages are Sent

CDMA messages on both forward and reverse traffic channels are normally sent via dim-and-burstMessages include many fields of binary dataThe first byte of each message identifies message type: this allows the recipient to parse the contentsTo ensure no messages are missed, all CDMA messages bear serial numbers and important messages contain a bit requesting acknowledgmentMessages not promptly acknowledged are retransmitted several times. If not acknowledged, the sender may release the callField data processing tools capture and display the messages for study

MSG_TYPE (‘00000110’)

ACK_SEQ

MSG_SEQ

ACK_REQ

ENCRYPTION

ERRORS_DETECTED

POWER_MEAS_FRAMES

LAST_HDM_SEQ

NUM_PILOTS

PILOT_STRENGTH

RESERVED (‘0’s)

8

3

3

1

2

5

10

2

4

6

0-7

NUM_PILOTS occurrences of this field:

Field Length (in bits)

EXAMPLE: A POWER MEASUREMENT

REPORT MESSAGE

t


Message Vocabulary: Acquisition & Idle StatesSync Channel

Sync Channel Msg

Pilot Channel

No Messages

Paging Channel

Access Parameters Msg

System Parameters Msg

CDMA Channel List Msg

Extended SystemParameters Msg

Extended NeighborList Msg

Global ServiceRedirection Msg

Order Msg•Base Station Acknowledgment

•Lock until Power-Cycled• Maintenance required

many others…..

AuthenticationChallenge Msg

Status Request Msg

Feature Notification Msg

TMSI Assignment Msg

Channel AssignmentMsg

SSD Update Msg

Service Redirection Msg

General Page Msg

Null Msg Data Burst Msg

Access Channel

Registration Msg

Order Msg• Mobile Station Acknowldgment• Long Code Transition Request

• SSD Update Confirmationmany others…..

Origination Msg

Page Response Msg

Authentication ChallengeResponse Msg

Status Response Msg

TMSI AssignmentCompletion Message

Data Burst Msg

BTS


Message Vocabulary: Conversation State

Reverse Traffic Channel

Order Message• Mobile Sta. Acknowledgment

•Long Code Transition Request

• SSD Update Confirmation• Connect

Authentication ChallengeResponse Msg

Flash WithInformation Msg

Data Burst Message

Pilot StrengthMeasurement Msg

Power MeasurementReport Msg

Send Burst DTMF Msg

OriginationContinuation Msg

Handoff Completion Msg

Parameters ResponseMessage

Service Request Msg

Service Response Msg

Service ConnectCompletion Message

Service Option ControlMessage

Status Response Msg

TMSI AssignmentCompletion Message

Forward Traffic ChannelOrder Msg

• Base Station Acknowledgment • Base Station Challenge

Confirmation• Message Encryption Mode

AuthenticationChallenge Msg

Alert WithInformation Msg

Data Burst Msg

Analog HandoffDirection Msg

In-Traffic SystemParameters Msg

Neighbor ListUpdate Msg

Send Burst DTMF Msg

Power ControlParameters Msg.

Retrieve Parameters Msg

Set Parameters Msg

SSD Update Msg

Flash WithInformation Msg

Mobile StationRegistered Msg

Status Request Msg

Extended HandoffDirection Msg

Service Request Msg

Service Response Msg

Service Connect Msg

Service OptionControl Msg

TMSI Assignment Msg


Section E

CDMA Handset ArchitectureCDMA Handoffs

CDMA Handset ArchitectureCDMA Handoffs


What’s In a Handset? How does it work?

ReceiverRF SectionIF, Detector

TransmitterRF Section

Vocoder

Digital Rake Receiver

Traffic CorrelatorPN xxx Walsh xx ΣTraffic CorrelatorPN xxx Walsh xxTraffic CorrelatorPN xxx Walsh xx

Pilot SearcherPN xxx Walsh 0

Viterbi Decoder,Convl. Decoder,Demultiplexer

CPUDuplexer

TransmitterDigital Section

Long Code Gen.

Open Loop Transmit Gain Adjust

Messages

Messages

Audio

Audio

Packets

Symbols

SymbolsChips

RF

RF

AGC

time-

alig

ned

su

mm

ing

pow

er

Traffic CorrelatorPN xxx Walsh xx

Δtcont

rol

bits


The Rake Receiver

Every frame, handset uses combined outputs of the three traffic correlators (“rake fingers”)Each finger can independently recover a particular PN offset andWalsh codeFingers can be targeted on delayed multipath reflections, or even on different BTSsSearcher continuously checks pilots

Handset Rake Receiver

RF

PN Walsh

PN Walsh

PN Walsh

SearcherPN W=0

ΣVoice,Data,

Messages

Pilot Ec/Io

BTS

BTS


CDMA Soft Handoff Mechanics

CDMA soft handoff is driven by the handset• Handset continuously checks available pilots• Handset tells system pilots it currently sees• System assigns sectors (up to 6 max.), tells handset• Handset assigns its fingers accordingly• All messages sent by dim-and-burst, no muting!

Each end of the link chooses what works best, on a frame-by-frame basis!

• Users are totally unaware of handoff


RFPN Walsh

PN Walsh

PN Walsh

SearcherPN W=0

ΣVoice,Data,

Messages

Pilot Ec/Io

BTS

BSCSwitch

BTS

Sel.


The Complete Rules of Soft Handoff

The Handset considers pilots in sets• Active: pilots of sectors actually in use• Candidates: pilots mobile requested, but

not yet set up & transmitting by system• Neighbors: pilots told to mobile by system,

as nearby sectors to check• Remaining: any pilots used by system but

not already in the other sets (div. by PILOT_INC)

Handset sends Pilot Strength Measurement Message to the system whenever:

• It notices a pilot in neighbor or remaining set exceeds T_ADD

• An active set pilot drops below T_DROP for T_TDROP time

• A candidate pilot exceeds an active by T_COMP

The System may set up all requested handoffs, or it may apply special manufacturer-specific screening criteria and only authorize some

65

Remaining

ActiveCandidateNeighbor 20

PILOT SETS

Min. M

embers

Req’d. B

y Std.

T_COMPT_ADD T_DROPT_TDROP

HANDOFF PARAMETERS

Exercise: How does a pilot in one set migrate into another set, for all cases? Identify the trigger, and the messages involved.


Softer Handoff

Each BTS sector has unique PN offset & pilot Handset will ask for whatever pilots it wantsIf multiple sectors of one BTS simultaneously serve a handset, this is called Softer HandoffHandset can’t tell the difference, but softer handoff occurs in BTS in a single channel elementHandset can even use combination soft-softer handoff on multiple BTS & sectors


RFPN Walsh

PN Walsh

PN Walsh

SearcherPN W=0

ΣVoice,Data,

Messages

Pilot Ec/Io

BTS

BSCSwitchSel.


What is Ec/Io?

Ec/Io is the measurement mobiles use to gauge strengths of the various nearby sectors they encounter

• Ec means the energy per chip of the pilot of the observed sector

• Io means the total power currently being picked up by the mobile

≈ x

LO

≈

RX Level(from AGC)

IFLNA

BW~30

MHz.

BW1.25MHz.

Handset Receiver

R

R

R

S

Rake

Why can’t the mobile just measure the signal strength of a sector directly with its receiver?

• all sectors are on the same frequency• the measurable signal strength on that frequency is just the

sum of all the individual signal powers• to distinguish them individually CDMA decoding must be used

Each sector dedicates 10-15% of its power to a steady test signal called the “pilot”. Mobiles can easily measure the pilot of a sector, determining its strength as a percentage of total received power


Light Traffic Loading

Heavily Loaded

How Ec/Io Varies with Traffic Loading

Each sector transmits a certain amount of power, the sum of:

• pilot, sync, and paging• any traffic channels in use

at that momentEc/Io is the ratio of pilot power to total power

• On a sector with nobody talking, Ec/Io is typically about 50%, which is -3 db

• On a sector with maximum traffic, Ec/Io is typically about 20%, which is -7 db.

Ec/Io = (2/4)= 50%

= -3 db.

Ec/Io = (2/10)= 20%

= -7 db.

2w

1.5w

Pilot

PagingSync

I0

EC

Traffic Channels

6w

0.5w

2w

1.5w

Pilot

PagingSync I0EC

0.5w


Many Sectors, Nobody Dominant

One Sector Dominant

How Ec/Io varies with RF Environment

In a “clean situation”, one sector is dominant and the mobile enjoys an Ec/Io just as good as it was when transmittedIn “pilot pollution”, too many sectors overlap and the mobile hears a “soup” made up of all their signals

• Io is the power sum of all the signals reaching the mobile

• Ec is the energy of a single sector’s pilot

• The large Io overrides the weak Ec; Ec/Io is low!

Io = -90 dbmEc = -96 dbmEc/Io = -6 db

Io = 10 signalseach -90 dbm

= -80 dbmEc of any onesector = -96

Ec/Io = -16 db

2w

1.5w

Pilot

PagingSync

I0

ECTraffic

Channels

4w

0.5w

BTS1

I0

EC

BTS2

BTS3

BTS4

BTS5

BTS6

BTS7

BTS8

BTS9

BTS10

PilotSync & Paging

TrafficPilot

Sync & PagingTraffic

PilotSync & Paging

TrafficPilot


PilotSync & Paging

TrafficPilot


PilotSync & Paging

TrafficPilot


PilotSync & Paging

TrafficPilot



CDMA Call ProcessingCDMA Call Processing

Section F


Let’s Acquire the System!Let’s Acquire the System!

Example 1


Find a Frequency with a CDMA RF Signal

Mobile scans forward link frequencies:(Cellular or PCS, depending on model)

History ListPreferred Roaming List

until a CDMA signal is found.NO CDMA?! Go to AMPS,

or to a power-saving standby mode

HISTORYLIST/MRU

Last-used:FreqFreqFreqFreqFreqetc.

FREQUENCY LISTS:PREFERREDROAMINGLIST/PRL

System1System2System3System4System5etc.

Forward Link Frequencies(Base Station Transmit)

A D B E F C unlic.data

unlic.voice A D B E F C

1850MHz. 1910MHz. 1990 MHz.1930MHz.

1900 MHz. PCS Spectrum

824 MHz. 835 845 870 880 894

869

849

846.5825

890

891.5

Paging, ESMR, etc.A B A B

800 MHz. Cellular Spectrum

Reverse Link Frequencies(Mobile Transmit)


How Idle Mobiles Choose CDMA CarriersAt turnon, Idle mobiles use proprietary algorithms to find the initial CDMA carrier intended for them to useWithin that CDMA signal, two types of paging channel messages could cause the idle mobile to choose another frequency: CDMA Channel List Message and GSRM

Go to last frequency from MRU

Strongest PN, read

SyncIs SID

permitted?

No Signal

Preferred Only Bit 0

Denied SIDRead

Paging Channel

CDMA Ch List Message

Global Svc Redir Msg

HASH using IMSI

my ACCOLC? redirect

Is better SID

available?

PRLMRU Acq IdxYes

NoF1F2F3

to Analog

to another CDMA frequency or system

ConfigMessages:

remain

Steps from the CDMA standards

Steps from proprietary

SDAs

Proprietary SDA

databases

Start

LegendTypical MobileSystem Determination Algorithm


Find Strongest Pilot, Read Sync Channel

Rake Fingers

Reference PN

Active Pilot

Ec/

Io

00

32K512

ChipsPN

1. Pilot Searcher Scans the Entire Range of PNs

All PN Offsets0

-20

98/05/24 23:14:09.817 [SCH] MSG_LENGTH = 208 bitsMSG_TYPE = Sync Channel MessageP_REV = 3MIN_P_REV = 2SID = 179NID = 0PILOT_PN = 168Offset IndexLC_STATE = 0x0348D60E013SYS_TIME = 98/05/24 23:14:10.160LP_SEC = 12LTM_OFF = -300 minutesDAYLT = 0PRAT = 9600 bpsRESERVED = 1

2. Put Rake finger(s) on strongest available PN, decode Walsh 32, and read Sync Channel Message

SYNC CHANNEL MESSAGE


RF≈ x ≈

LO Srch PN??? W0

F1 PN168 W32F2 PN168 W32F3 PN168 W32


The Configuration Messages

After reading the Sync Channel, the mobile is now capable of reading the Paging Channel, which it now monitors constantlyBefore it is allowed to transmit or operate on this system, the mobile must collect a complete set of configuration messages Collection is a short process -- all configuration messages are repeated on the paging channel every 1.28 secondsThe configuration messages contain sequence numbers so the mobile can recognize if any of the messages have been freshly updated as it continues to monitor the paging channel

• Access parameters message sequence number• Configuration message sequence number• If a mobile notices a changed sequence number, or if 600

seconds passes since the last time these messages were read, the mobile reads all of them again


Go to Paging Channel, Get Configured

Rake Fingers

Reference PN

Active Pilot

Ec/

Io

00

32K512

ChipsPN

All PN Offsets0

-20

Keep Rake finger(s) on strongest available PN, decode Walsh 1,

and monitor the Paging Channel

Read the Configuration Messages

Access Parameters Msg

System Parameters Msg

CDMA Channel List Msg

Extended SystemParameters Msg (*opt.)

(Extended*) NeighborList Msg

Global ServiceRedirection Msg (*opt.)

Now we’re ready to operate!!


RF≈ x ≈

LO Srch PN??? W0

F1 PN168 W01F2 PN168 W01F3 PN168 W01


Two Very Important Configuration Messages

98/05/24 23:14:10.427 [PCH] MSG_LENGTH = 184 bitsMSG_TYPE = Access Parameters MessagePILOT_PN = 168 Offset IndexACC_MSG_SEQ = 27ACC_CHAN = 1 channelNOM_PWR = 0 dB INIT_PWR = 0 dB PWR_STEP = 4 dBNUM_STEP = 5 Access Probes MaximumMAX_CAP_SZ = 4 Access Channel Frames MaximumPAM_SZ = 3 Access Channel FramesPersist Val for Acc Overload Classes 0-9 = 0Persist Val for Acc Overload Class 10 = 0Persist Val for Acc Overload Class 11 = 0Persist Val for Acc Overload Class 12 = 0Persist Val for Acc Overload Class 13 = 0Persist Val for Acc Overload Class 14 = 0Persist Val for Acc Overload Class 15 = 0Persistance Modifier for Msg Tx = 1 Persistance Modifier for Reg = 1 Probe Randomization = 15 PN chipsAcknowledgement Timeout = 320 msProbe Backoff Range = 4 Slots MaximumProbe Sequence Backoff Range = 4 Slots Max.Max # Probe Seq for Requests = 2 SequencesMax # Probe Seq for Responses = 2 SequencesAuthentication Mode = 1Random Challenge Value = Field OmittedReserved Bits = 99

ACCESS PARAMETERS MESSAGE98/05/24 23:14:11.126 [PCH] MSG_LENGTH = 264 bitsMSG_TYPE = System Parameters MessagePILOT_PN = 168 Offset IndexCONFIG_MSG_SEQ = 0SID = 179 NID = 0REG_ZONE = 0 TOTAL_ZONES = 0 ZONE_TIMER = 60 minMULT_SIDS = 0 MULT_NID = 0 BASE_ID = 8710BASE_CLASS = Public MacrocellularPAGE_CHAN = 1 channelMAX_SLOT_CYCLE_INDEX = 0HOME_REG = 0 FOR_SID_REG = 0 FOR_NID_REG = 1POWER_UP_REG = 0 POWER_DOWN_REG = 0PARAMETER_REG = 1 REG_PRD = 0.08 secBASE_LAT = 00D00'00.00N BASE_LONG = 000D00'00.00EREG_DIST = 0SRCH_WIN_A = 40 PN chipsSRCH_WIN_N = 80 PN chipsSRCH_WIN_R = 4 PN chipsNGHBR_MAX_AGE = 0PWR_REP_THRESH = 2 framesPWR_REP_FRAMES = 56 framesPWR_THRESH_ENABLE = 1PWR_PERIOD_ENABLE = 0PWR_REP_DELAY = 20 framesRESCAN = 0T_ADD = -13.0 Db T_DROP = -15.0 dB T_COMP = 2.5 dBT_TDROP = 4 secEXT_SYS_PARAMETER = 1RESERVED = 0GLOBAL_REDIRECT = 0

SYSTEM PARAMETERS MESSAGE


Four Additional Configuration Messages

98/05/24 23:14:10.946 [PCH] MSG_LENGTH = 104 bitsMSG_TYPE = Extended System Parameters MessagePILOT_PN = 168 Offset IndexCONFIG_MSG_SEQ = 0 RESERVED = 0PREF_MSID_TYPE = IMSI and ESNMCC = 000 IMSI_11_12 = 00 RESERVED_LEN = 8 bitsRESERVED_OCTETS = 0x00 BCAST_INDEX = 0RESERVED = 0

EXTENDED SYSTEM PARAMETERS

98/05/17 24:21.566 Paging Channel: Global Service RedirectionPILOT_PN: 168, MSG_TYPE: 96, CONFIG_MSG_SEQ: 0Redirected access overload classes: { 0, 1 }, RETURN_IF_FAIL: 0, DELETE_TMSI: 0, Redirection to an analog system: EXPECTED_SID = 0 Do not ignore CDMA Available indicator on the redirected analog systemAttempt service on either System A or B with the custom system selection process

GLOBAL SERVICE REDIRECTION

98/05/24 23:14:11.486 [PCH]MSG_LENGTH = 216 bitsMSG_TYPE = Neighbor List MessagePILOT_PN = 168 Offset IndexCONFIG_MSG_SEQ = 0PILOT_INC = 4 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 220 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 52 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 500 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 8 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 176 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 304 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 136 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 384 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 216 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 68 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 328 Offset IndexNGHBR_CONFIG = 0 NGHBR_PN = 112 Offset IndexRESERVED = 0

NEIGHBOR LIST

98/05/24 23:14:10.786 [PCH]MSG_LENGTH = 72 bitsMSG_TYPE = CDMA Channel List MessagePILOT_PN = 168 Offset IndexCONFIG_MSG_SEQ = 0CDMA_FREQ = 283RESERVED = Field Omitted

CDMA CHANNEL LIST MESSAGE


Let’s do an Idle Mode Handoff!

Let’s do an Idle Mode Handoff!

Example 2


Idle Mode Handoff

An idle mobile always demodulates the best available signal• In idle mode, it isn’t possible to do soft handoff and listen to

multiple sectors or base stations at the same time -- the paging channel information stream is different on each sector, not synchronous -- just like ABC, NBC, CBS, and CNN TV news programs aren’t in word-sync for simultaneous viewing

• Since a mobile can’t combine signals, the mobile must switch quickly, always enjoying the best available signal

The mobile’s pilot searcher is constantly checking neighbor pilotsIf the searcher notices a better signal, the mobile continues on the current paging channel until the end of the current superframe, then instantly switches to the paging channel of the new signal

• The system doesn’t know the mobile did this! (Does NBC’s Tom Brokaw know you just switched your TV to CNN?)

On the new paging channel, if the mobile learns that registration is required, it re-registers on the new sector


Idle Mode on the Paging Channel: Meet the Neighbors, track the Strongest Pilot

Ec/

IoAll PN Offsets

00

32K512

ChipsPN

0

-20

Neighbor Set

The phone’s pilot searcher constantly checks the pilots listed in the Neighbor List Message

If the searcher ever notices a neighbor pilot substantially stronger than the current reference pilot, it becomes the new reference pilot

and the phone switches over to its paging channel on the next superframe.This is called an idle mode handoff.

Rake Fingers

Reference PN

Active Pilot

SRCH_WIN_A

SRCH_WIN_N

Mobile Rake RX

Srch PN??? W0

F1 PN168 W01F2 PN168 W01F3 PN168 W01


Phone Operation on the Access Channel

A sector’s Paging Channel announces 1 (typ) to 32 (max) Access Channels: PN Long Code offsets for mobiles to use if accessing the system.

• For mobiles sending Registration, Origination, Page Responses

• Base Station always listening!On the access channel, phones are not yet under BTS closed-loop power control!Phones access the BTS by “probing” at power levels determined by receive power and an open loop formula

• If “probe” not acknowledged by BTS within ACC_TMO (~400 mS.), phone will wait a random time (~200 mS) then probe again, stronger by PI db.

• There can be 15 max. (typ. 5) probes in a sequence and 15 max. (typ. 2) sequences in an access attempt

• most attempts succeed on first probe!The Access Parameters message on the paging channel announces values of all related parameters

ACCESS

RV TFC

BTS

Channel Assnmt. Msg.

Origination Msg

Base Sta. Acknlgmt. Order

TFC frames of 000s

TFC preamble of 000s


Mobile Sta. Ackngmt. Order

Service Connect Msg.

Svc. Connect Complete Msg


Call is Established!

MSProbing

PAGING

FW TFC

PAGING

RV TFC

FW FC

RV TFC

FW TFC

FW TFC

A Successful Access Attempt

a Probe Sequencean Access Attempt

Success!

an Access Probe


Let’s Register!Let’s Register!

Example 3


Registration

Registration is the process by which an idle mobile lets the system know it’s awake and available for incoming calls

• this allows the system to inform the mobile’s home switch of the mobile’s current location, so that incoming calls can be delivered

• registration also allows the system to intelligently page the mobile only in the area where the mobile is currently located, thereby eliminating useless congestion on the paging channels in other areas of the system

There are many different conditions that could trigger an obligation for the mobile to register

• there are flags in the System Parameters Message which tell the mobile when it must register on the current system


An Actual Registration

16:18:27.144 Access Channel: Registration ACK_SEQ: 7 MSG_SEQ: 1 ACK_REQ: 1 VALID_ACK: 0ACK_TYPE: 0MSID_TYPE: 3, ESN: [0x 01 99 0d fc]MFR 1, Reserved 38, Serial Number 69116,IMSI: (Class: 0, Class_0_type: 1) [0x 01 8d 31 74 29 36]00-416-575-0421AUTH_MODE: 0REG_TYPE: Timer-basedSLOT_CYCLE_INDEX: 2MOB_P_REV: 1EXT_SCM: 1SLOTTED_MODE: 1MOB_TERM: 1

REGISTRATION MESSAGE

18:26.826 [PCH] System Parameters Message Pilot_PN: 32CONFIG_MSG_SEQ: 14 SID: 16420 NID: 0,REG_ZONE: 0 TOTAL_ZONES: 0 Zone timer length (min): 1MULT_SIDS: 0 MULT_NIDS: 0 BASE_ID: 1618 BASE_CLASS: ReservedPAG_CHAN: 1 MAX_SLOT_CYCLE_INDEX: 2 HOME_REG: 1 FOR_SID_REG: 1 FOR_NID_REG: 1, POWER_UP_REG: 1 POWER_DOWN_REG: 1 PARAMETER_REG: 1 Registration period (sec): 54 Base station 0°00´00.00¨ Lon., 0°00´00.00° Lat. REG_DIST: 0SRCH_WIN_A (PN chips): 28 SRCH_WIN_N (PN chips): 100, SRCH_WIN_R (PN chips): 130 NGHBR_MAX_AGE: 2PWR_REP_THRESH: 2 PWR_REP_FRAMES (frames): 15PWR_THRESH_ENABLE: 1 PWR_PERIOD_ENABLE: 0, PWR_REP_DELAY: 1 (4 frames) RESCAN: 0, T_ADD: -14.0dB T_DROP: -16.0dB T_COMP: 2.5dB, T_TDROP: 4s EXT_SYS_PARAMETER: 1 EXT_NGHBR_LIST: 1 GLOBAL_REDIRECT: 0

SYSTEM PARAMETERS MESSAGE

16:18:27.506 Paging Channel: Order ACK_SEQ: 1 MSG_SEQ: 0 ACK_REQ: 0 VALID_ACK: 1 MSID_TYPE: 2 IMSI: (Class: 0, Class_0_type: 3) [0x 02 47 8d 31 74 29 36] (302) 00-416-575-0421Order type: Base Station Acknowledgement Order

BASE STATION ACKNOWLEDGMENT

The System Parameters Message tells all mobiles when they should register.

This mobile notices that it is obligated to register, so it transmits a Registration

Message.

The base station confirms that the mobile’s registration message was received. We’re officially registered!


Let’s Receive an incoming Call!

Let’s Receive an incoming Call!

Example 4


Receiving an Incoming Call

All idle mobiles monitor the paging channel to receive incoming calls.When an incoming call appears, the paging channel notifies the mobile in a General Page Message.A mobile which has been paged sends a Page Response Message on the access channel.The system sets up a traffic channel for the call, then notifies the mobile to use it with a Channel Assignment Message.The mobile and the base station notice each other’s traffic channel signals and confirm their presence by exchanging acknowledgment messages.The base station and the mobile negotiate what type of call this will be -- I.e., 13k voice, etc.The mobile is told to ring and given a “calling line ID” to display.When the human user presses the send button, the audio path is completed and the call proceeds.


An Actual Page and Page Response

98/05/24 23:14:46.425 [ACH] Page Response MessageMSG_LENGTH = 216 bitsMSG_TYPE = Page Response MessageACK_SEQ = 1 MSG_SEQ = 2 ACK_REQ = 1VALID_ACK = 1 ACK_TYPE = 2MSID_TYPE = IMSI and ESN MSID_LEN = 9 octetsESN = 0xD30E415C IMSI_CLASS = 0IMSI_CLASS_0_TYPE = 0 RESERVED = 0IMSI_S = 6153300644AUTH_MODE = 1AUTHR = 0x307B5 RANDC = 0xC6 COUNT = 0MOB_TERM = 1 SLOT_CYCLE_INDEX = 0MOB_P_REV = 3 SCM = 106REQUEST_MODE = Either Wide Analog or CDMA OnlySERVICE_OPTION = 32768 PM = 0NAR_AN_CAP = 0 RESERVED = 0

PAGE RESPONSE MESSAGE

98/05/24 23:14:46.127 [PCH] General Page MessageMSG_LENGTH = 128 bits MSG_TYPE = General Page MessageCONFIG_MSG_SEQ = 1 ACC_MSG_SEQ = 20CLASS_0_DONE = 1CLASS_1_DONE = 1 RESERVED = 0BROADCAST_DONE = 1 RESERVED = 0ADD_LENGTH = 0 bits ADD_PFIELD = Field OmittedPAGE_CLASS = 0 PAGE_SUBCLASS = 0MSG_SEQ = 1 IMSI_S = 6153300644SPECIAL_SERVICE = 1SERVICE_OPTION = 32768RESERVED = Field Omitted

GENERAL PAGE MESSAGE

98/05/24 23:14:46.768 [PCH] Order MessageMSG_LENGTH = 112 bitsMSG_TYPE = Order MessageACK_SEQ = 2 MSG_SEQ = 0 ACK_REQ = 0VALID_ACK = 1 ADDR_TYPE = IMSI ADDR_LEN = 40 bitsIMSI_CLASS = 0 IMSI_CLASS_0_TYPE = 0 RESERVED = 0 IMSI_S = 6153300644ORDER = Base Station Acknowledgement OrderADD_RECORD_LEN = 0 bitsOrder-Specific Fields = Field Omitted RESERVED = 0


The system pages the mobile, 615-330-0644.

The base station confirms that the mobile’s page response was received. Now the

mobile is waiting for channel assignment,expecting a response within 12 seconds.

The mobile responds to the page.


Channel Assignment and Traffic Channel Confirmation

18:14:47.598 Reverse Traffic Channel: Order ACK_SEQ: 0 MSG_SEQ: 0 ACK_REQ: 0 ENCRYPTION: 0Mobile Station Acknowledgement Order

MOBILE STATION ACKNOWLEDGMENT

18:14:47.027 Paging Channel: Channel Assignment ACK_SEQ: 2 MSG_SEQ: 1 ACK_REQ: 0 VALID_ACK: 1MSID_TYPE: 2 IMSI: (Class: 0, Class_0_type: 0) [0x 01 f8 39 6a 15] 615-330-0644 ASSIGN_MODE: Traffic Channel AssignmentADD_RECORD_LEN: 5 FREQ_INCL: 1 GRANTED_MODE: 2CODE_CHAN: 43 FRAME_OFFSET: 2ENCRYPT_MODE: Encryption disabledBAND_CLASS: 800 MHz cellular bandCDMA_FREQ: 283

CHANNEL ASSIGNMENT MESSAGE

18:14:47.581 Forward Traffic Channel: Order ACK_SEQ: 7 MSG_SEQ: 0 ACK_REQ: 1 ENCRYPTION: 0 USE_TIME: 0 ACTION_TIME: 0Base Station Acknowledgement Order


Only about 400 ms. after the base station acknowledgment order, the mobile receives

the channel assignment message.

The base station is already sending blank frames on

the forward channel,using the assigned Walsh code.

The mobile sees at least two good blank frames in a row on

the forward channel, and concludes this is the right traffic channel. It sends a preamble of two blank frames of its own on the reverse traffic channel.

The base station acknowledges receiving the mobile’s preamble.

The mobile station acknowledges the base station’s acknowledgment.

Everybody is ready!


Service Negotiation and Mobile Alert

18:14:47.835 Reverse Traffic Channel: Service Connect Completion ACK_SEQ: 1 MSG_SEQ: 3 ACK_REQ: 1 ENCRYPTION: 0 SERV_CON_SEQ: 0

SERVICE CONNECT COMPLETE MSG.

18:14:47.760 Forward Traffic Channel: Service Connect ACK_SEQ: 0 MSG_SEQ: 1 ACK_REQ: 0 ENCRYPTION: 0USE_TIME: 0 ACTION_TIME: 0 SERV_CON_SEQ: 0Service Configuration: supported Transmission: Forward Traffic Channel Rate (Set 2): 14400, 7200, 3600, 1800 bps Reverse Traffic Channel Rate (Set 2): 14400, 7200, 3600, 1800 bps Service option: (6) Voice (13k) (0x8000) Forward Traffic Channel: Primary Traffic Reverse Traffic Channel: Primary Traffic

SERVICE CONNECT MESSAGENow that both sides have arrived on the

traffic channel, the base station proposes that the requested call

actually begin.

The mobile agrees and says its ready to play.

18:14:47.961 Forward Traffic Channel: Alert With Information ACK_SEQ: 3 MSG_SEQ: 1 ACK_REQ: 1 ENCRYPTION: 0SIGNAL_TYPE = IS-54B Alerting ALERT_PITCH = Medium Pitch (Standard Alert)SIGNAL = Long RESERVED = 0RECORD_TYPE = Calling Party NumberRECORD_LEN = 96 bitsNUMBER_TYPE = National NumberNUMBER_PLAN = ISDN/Telephony Numbering PlanPI = Presentation Allowed SI = Network ProvidedCHARi = 6153000124 RESERVED = 0 RESERVED = 0

ALERT WITH INFORMATION MESSAGE

The base station orders the mobile to ring, and gives it the calling party’s number to display.

18:14:48.018 Reverse Traffic Channel: Order ACK_SEQ: 1 MSG_SEQ: 4 ACK_REQ: 0ENCRYPTION: 0 Mobile Station Acknowledgement Order

The mobile says it’s ringing.

SERVICE CONNECT COMPLETE is a major milestone in call processing. Up until now, this was an access attempt.

Now it is officially a call.


The Human Answers! Connect Order

The mobile has been ringing for several seconds. The human user finally comes over and presses the send

button to answer the call.

Now the switch completes the audio circuit and the two callers can talk!

18:14:54.920 Forward Traffic Channel: Order ACK_SEQ: 0 MSG_SEQ: 1 ACK_REQ: 0 ENCRYPTION: 0 USE_TIME: 0 ACTION_TIME: 0 Base Station Acknowledgement Order


18:14:54.758 Reverse Traffic Channel: Order ACK_SEQ: 6 MSG_SEQ: 0 ACK_REQ: 1 ENCRYPTION: 0 Connect Order

CONNECT ORDER


Let’s make an Outgoing Call!Let’s make an Outgoing Call!

Example 5


Placing an Outgoing Call

The mobile user dials the desired digits, and presses SEND.Mobile transmits an Origination Message on the access channel.The system acknowledges receiving the origination by sending a base station acknowledgement on the paging channel.The system arranges the resources for the call and starts transmitting on the traffic channel.The system notifies the mobile in a Channel Assignment Message on the paging channel.The mobile arrives on the traffic channel.The mobile and the base station notice each other’s traffic channel signals and confirm their presence by exchanging acknowledgment messages.The base station and the mobile negotiate what type of call this will be -- I.e., 13k voice, etc.The audio circuit is completed and the mobile caller hears ringing.


Origination17:48:53.144 Access Channel: Origination ACK_SEQ: 7 MSG_SEQ: 6 ACK_REQ: 1 VALID_ACK: 0 ACK_TYPE: 0 MSID_TYPE: 3 ESN: [0x 00 06 98 24] MFR 0 Reserved 1 Serial Number 170020 IMSI: (Class: 0, Class_0_type: 0) [0x 03 5d b8 97 c2] 972-849-5073AUTH_MODE: 0 MOB_TERM: 1SLOT_CYCLE_INDEX: 2 MOB_P_REV: 1 EXT_SCM: 1DualMode: 0 SLOTTED_MODE: 1 PowerClass: 0REQUEST_MODE: CDMA only SPECIAL_SERVICE: 1 Service option: (6) Voice (13k) (0x8000) PM: 0 DIGIT_MODE: 0 MORE_FIELDS: 0 NUM_FIELDS: 11Chari: 18008900829 NAR_AN_CAP: 0

ORIGINATION MESSAGE

17:48:53.487 Paging Channel: Order ACK_SEQ: 6 MSG_SEQ: 0 ACK_REQ: 0 VALID_ACK: 1 MSID_TYPE: 2IMSI: (Class: 0, Class_0_type: 0) [0x 03 5d b8 97 c2] 972-849-5073 Base Station Acknowledgment Order


The mobile sends an origination message

on the access channel.

The base station confirms that the origination message

was received.17:48:54.367 Paging Channel: Channel Assignment ACK_SEQ: 6 MSG_SEQ: 1 ACK_REQ: 0 VALID_ACK: 1MSID_TYPE: 2 IMSI: (Class: 0, Class_0_type: 0) [0x 03 5d b8 97 c2] 972-849-5073 ASSIGN_MODE: Traffic Channel Assignment, ADD_RECORD_LEN: 5 FREQ_INCL: 1 GRANTED_MODE: 2CODE_CHAN: 12 FRAME_OFFSET: 0 ENCRYPT_MODE: Encryption disabled BAND_CLASS: 1.8 to 2.0 GHz PCS band CDMA_FREQ: 425

CHANNEL ASSIGNMENT MESSAGE

The base station sends a Channel Assignment

Message and the mobile goes to the traffic channel.


Traffic Channel Confirmation

17:48:54.835 Reverse Traffic Channel: Order ACK_SEQ: 0 MSG_SEQ: 0 ACK_REQ: 0 ENCRYPTION: 0 Mobile Station Acknowledgment Order

MOBILE STATION ACKNOWLEDGMENT17:48:54.757 Forward Traffic Channel: Order ACK_SEQ: 7 MSG_SEQ: 0 ACK_REQ: 1 ENCRYPTION: 0USE_TIME: 0 ACTION_TIME: 0 Base Station Acknowledgment Order


The base station is already sending blank frames on

the forward channel,using the assigned Walsh code.

The mobile sees at least two good blank frames in a row on

the forward channel, and concludes this is the right traffic channel. It sends a preamble of two blank frames of its own on the reverse traffic channel.

The base station acknowledges receiving the mobile’s preamble.

The mobile station acknowledges the base station’s acknowledgment.

Everybody is ready!


Service Negotiation and Connect Complete

17:48:55.137 Reverse Traffic Channel: Service Connect Completion ACK_SEQ: 1, MSG_SEQ: 0, ACK_REQ: 1, ENCRYPTION: 0, SERV_CON_SEQ: 0

SERVICE CONNECT COMPLETE MSG.

17:48:55.098 Forward Traffic Channel: Service Connect ACK_SEQ: 7 MSG_SEQ: 1 ACK_REQ: 1 ENCRYPTION: 0USE_TIME: 0 ACTION_TIME: 0 SERV_CON_SEQ: 0 Service Configuration Supported Transmission: Forward Traffic Channel Rate (Set 2): 14400, 7200, 3600, 1800 bpsReverse Traffic Channel Rate (Set 2): 14400, 7200, 3600, 1800 bpsService option: (6) Voice (13k) (0x8000) Forward Traffic Channel: Primary TrafficReverse Traffic Channel: Primary Traffic

SERVICE CONNECT MESSAGENow that the traffic channel is working

in both directions, the base station proposes that the requested call

actually begin.

The mobile agrees and says its ready to play.

17:48:55.779 Forward Traffic Channel: Order ACK_SEQ: 0 MSG_SEQ: 0 ACK_REQ: 0 ENCRYPTION: 0USE_TIME: 0 ACTION_TIME: 0 Base Station Acknowledgment Order


The base station agrees. SERVICE CONNECT COMPLETE is a major milestone in call processing. Up until now, this was an access attempt.

Now it is officially a call.

Now the switch completes the audio circuit and the two callers can talk!


Let’s End a Call!Let’s End a Call!

Example 6


Ending A Call

A normal call continues until one of the parties hangs up. Thataction sends a Release Order, “normal release”. The other side of the call sends a Release Order, “no reason given”.

• If a normal release is visible, the call ended normally.At the conclusion of the call, the mobile reacquires the system.

• Searches for the best pilot on the present CDMA frequency• Reads the Sync Channel Message• Monitors the Paging Channel steadily

Several different conditions can cause a call to end abnormally:• the forward link is lost at the mobile, and a fade timer acts• the reverse link is lost at the base station, and a fade timer acts• a number of forward link messages aren’t acknowledged, and the

base station acts to tear down the link• a number of reverse link messages aren’t acknowledged, and the

mobile station acts to tear down the link


A Beautiful End to a Normal Call

17:49:21.715 Reverse Traffic Channel: Order ACK_SEQ: 1 MSG_SEQ: 1 ACK_REQ: 1 ENCRYPTION: 0 Release Order (normal release)

MOBILE RELEASE ORDER

BASE STATION ACKNOWLEDGMENT17:49:21.936 Forward Traffic Channel: Order ACK_SEQ: 1 MSG_SEQ: 2 ACK_REQ: 0 ENCRYPTION: 0, USE_TIME: 0 ACTION_TIME: 0 Base Station Acknowledgement Order

At the end of a normal call, this mobile user pressed end.

The mobile left the traffic channel, scanned to find the best pilot, and read

the Sync Channel Message.

BASE STATION RELEASE ORDER17:49:21.997 Forward Traffic Channel: Order ACK_SEQ: 1 MSG_SEQ: 3 ACK_REQ: 0 ENCRYPTION: 0USE_TIME: 0 ACTION_TIME: 0 Release Order (no reason given)

17:49:22.517 Sync Channel MSG_TYPE: 1 Sync Channel MessageP_REV: 1 MIN_P_REV: 1SID: 4112 NID: 2 Pilot_PN: 183 LC_STATE: 0x318fe5d84a5 SYS_TIME: 0x1ae9683dcLP_SEC: 9 LTM_OFF: -10 DAYLT: 1 Paging Channel Data Rate: 9600 CDMA_FREQ: 425

SYNC CHANNEL MESSAGE

The base station acknowledged receiving the message, then sent

a release message of its own.


Let’s receive Notificationof a Voice Message!

Let’s receive Notificationof a Voice Message!

Example 7


Feature Notification

98/06/30 21:16:44.368 [PCH] Feature Notification MessageMSG_LENGTH = 144 bitsMSG_TYPE = Feature Notification MessageACK_SEQ = 0MSG_SEQ = 0ACK_REQ = 1VALID_ACK = 0ADDR_TYPE = IMSIADDR_LEN = 56 bitsIMSI_CLASS = 0IMSI_CLASS_0_TYPE = 3RESERVED = 0MCC = 302IMSI_11_12 = 00IMSI_S = 9055170325RELEASE = 0RECORD_TYPE = Message WaitingRECORD_LEN = 8 bitsMSG_COUNT = 1RESERVED = 0

FEATURE NOTIFICATION MESSAGE

The Feature Notification Message on the Paging Channel tells a specific mobile it has voice messages waiting.

There are other record types to notify the mobile of other features.

The mobile confirms it has received the notification by sending a Mobile Station Acknowledgment Order on the access

channel.



Let’s do a Handoff!Let’s do a Handoff!

Example 8

February, 2008Technical Introduction to CDMA v6 (c) 2008 Scott BaxterTechnical Introduction to Wireless -- ©1997 Scott Baxter - V0.0107

54 102 134 200 248 300 328 396 416 420 488 504

SYSTEM ACQUISITIONAt turn-on, and after the end of every call, a mobile

makes a fresh attempt to acquire the system. It scans all the PN offsets in tiny steps to be sure no pilot signal is missed. After the scan is complete, the mobile locks to the strongest pilot it has found.

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IDLE MODE The strongest pilot is now the only Active pilot.

The mobile puts its rake fingers on this PN and decodes Walsh Code 32, the Sync channel.The Sync channel announces the system (SID) and network (NID); how to make the long code properly synchronized (Long Code State); and when the 20 ms. frames begin on the Paging and traffic channels.Now the mobile knows how to receive the paging channel!

It begins continuously listening to the paging channel. Soon it receives the neighbor list message.

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3 Db, 5 sec.

IDLE MODE HANDOFF

In idle mode, listening to the paging channel, the mobile can have only one active pilot at a time. Soft handoff is not possible during idle mode, since the messages on one sector’s paging channel do not match the messages on another sector’s paging channel.

The mobile’s pilot searcher is continuously checking both the active pilot (to keep the rake fingers aligned on the best multipath signals) and the neighbor pilots. If a neighbor pilot is noticed at least 3 db stronger than the current active pilot, and it remains so for 5 seconds, the mobile just stops listening to the old active and the stronger neighbor becomes the new active pilot. If the current active pilot should fade and the mobile loses the paging channel, it is allowed to switch to another stronger sector immediately without waiting 5 seconds.

The system does not even know the mobile has done an idle mode handoff, since no messages are exchanged. The mobile just starts listening to a different sector!Of course, if the mobile notices that the new sector has a different SID or NID from the old sector, it will register to let the new system know it has arrived.

(Settable parameters)

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T_ADD

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IN CALL

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When a mobile begins a call, it has only one active pilot – the same sector it was listening to in idle mode. It remembers the same neighbor list from its idle time.During a call, the mobile’s pilot searcher is scanning alternately the active pilot and each pilot on the neighbor list.If the mobile notices any pilots with EC/IO above T_Add, it will immediately send a PSMM to the system, asking for handoff with them.

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PSMM: PN248, -5, keep; PN134, -10, keep; PN102, -11.5, keep BTS

SEE ADDITIONAL PILOTS >T_ADD,

SEND PSMM!!


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IN CALL

T_ADD

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After the mobile has sent the PSMM, the newly-requested pilots are considered “Candidates”. The mobile cannot begin listening to them yet, because they do not have channel elements set up yet to simulcast the traffic channel, and the mobile must also be told which walsh codes have been assigned for it to listen to.The mobile patiently waits for the Extended Handoff Direction Message.

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T_ADD

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EHDM: PN248, W14; PN134, W08; PN102, W52 BTS

IN CALL With approximately 500 ms after sending the PSMM, the mobile receives the Extended Handoff Direction Message (EHDM). The base station has authorized the handoff on all the requested sectors, and included the walsh codes the mobile must know in order to hear the sectors.After beginning to use the new pilots, the mobile confirms by sending a Handoff Completion Message. Then the system sends the mobile a new Neighbor List Update message.

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T_ADD

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IN CALL

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One of the active pilots, PN134, has faded below T_Drop.The mobile puts PN134 on a “probation watch” – waiting to see if it remains below T_Drop for T_TDrop seconds .

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AN ACTIVE PILOTFALLS BELOW

T_DROP

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T_ADD

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IN CALL

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If PN134 recovers, becoming stronger than T_Drop before the T_TDroptime has passed, the mobile “forgives” its earlier weakness and will not send a PSMM to request any change.

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PILOT RECOVERS,REMAINS ACTIVE

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T_ADD

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PN134 has faded below T_Drop again.The mobile puts PN134 on a “probation watch” – waiting to see if it remains below T_Drop for T_TDrop seconds .

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AN ACTIVE PILOTFALLS BELOW

T_DROPAGAIN

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T_ADD

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If PN134 remains below T_Drop for T_TDrop seconds, the mobile sends a PSMM requesting to drop it from the handoff.

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PSMM: PN248, -5, keep; PN134, -16, drop;PN102, -11.5, keep BTS

PILOT REMAINSBELOW T_DROPFOR T_TDROP

SECONDS.SEND PSMMTO REMOVE!

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The mobile waits for an Extended Handoff Direction Message (EHDM), giving permission to drop the pilot from the Active set.

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ReceiveEHDM,DropPilot EHDM: PN248, W14;

PN102, W52BTS


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Neig

hbor

Neig

hbor

abov

e T_A

dd

Neig

hbor

abov

e T_A

dd

Neig

hbor

abov

e T_A

dd

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALLSEE ADDITIONAL PILOTS >T_ADD,

SEND PSMM!!

The mobile has just noticed several neighbor pilots have risen above T_ADD. It will immediately send a PSMM requesting to add them in handoff. It quickly sends a PSMM requesting handoff with them.

PSMM: PN248, -5, keep; PN300, -3.5, keep;PN134, -10.5, keep; PN488, -10.5, keep;PN102, -11.5, keep; PN328, -11.5, keep;PN200, -12, keep; PN396, -12.5, keep;PN420, -12, keep; PN504, -12, keep BTS

Act

ive

Pilo

t

Neig

hbor

abov

e T_A

dd

Act

ive

Pilo

t


Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL

WAITfor EHDM

Act

ive

Pilo

t

Requ

este

d Ca

ndid

ate

Act

ive

Pilo

t


Neig

hbor

Neig

hbor


Act

ive

Pilo

t

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

RECEIVEEHDM

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

EHDM: PN300, W31; PN248, W14;PN134, W08; PN488, W10;PN328, W27; PN102, W52 BTS

IN CALL

The mobile receives the Extended Handoff Direction Message, and implements the handoff with the pilots listed in the message. The BSC has chosen the strongest six pilots requested in the previous PSMM. Only the strongest 6 signals requested by the mobile are chosen to be active.PN 200, PN396, PN420 and PN504 are Unassigned Candidates.

Neig

hbor

Neig

hbor


Neig

hbor

abov

e T_A

dd

Act

ive

Pilo

t

Act

ive

Pilo

t

Neig

hbor

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL PSMM: PN248, -5, keep; PN300, -3.5, keep;PN134, -10.5, keep; PN488, -10.5, keep;PN102, -11.5, keep; PN328, -11.5, keep;PN200, -12, keep; PN396, -12.5, keep;PN416, -10.5, keep; PN420, -12, keep; PN504, -12, keep

BTS

The mobile notices that PN416 has just grown stronger, and is now above T_Add. It sends a PSMM requesting handoff with it and the other 10 signals above T_Add.

SEE ADDITIONAL PILOTS >T_ADD,

SEND PSMM!!


Act

ive

Pilo

t

Act

ive

Pilo

t

Neig

hbor

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL

Requ

este

d Ca

ndid

ate


WAITfor EHDM


Neig

hbor

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

Unas

signe

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL

The mobile receives the Extended Handoff Direction Message, and implements the handoff with the pilots listed in the message. The BSC has chosen the strongest six pilots requested in the previous PSMM. Only the strongest 6 signals requested by the mobile are chosen to be active.Notice that PN416 replaces PN102. PN102, PN200, PN396, PN420 and PN504 are Unassigned Candidates.

RECEIVEEHDM


Unas

signe

d Ca

ndid

ate

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t


Neig

hbor

Requ

este

d Ca

ndid

ate

Act

ive

Pilo

t

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL

Suppose T_COMP = 4 db. The mobile notices that the strongest candidate, PN396, has grown T_COMP db stronger than the weakest active pilot, PN328.This triggers the mobile to send a new PSMM including all the pilots above T_ADD. All of them were already either actives or candidates, but the new PSMM includes the new current strength of each pilot.

Notice T_COMPtrigger, send

EHDM

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

PSMM: PN248, -5, keep; PN300, -3.5, keep;PN134, -10.5, keep; PN488, -10.5, keep;PN102, -11.5, keep; PN328, -14, keep;PN200, -12, keep; PN396, -10, keep;PN416, -10.5, keep; PN420, -12, keep; PN504, -12, keep

BTS

T_COMP


Neig

hbor

Requ

este

d Ca

ndid

ate

Act

ive

Pilo

t

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALLWAIT

for EHDM

Requ

este

d Ca

ndid

ate

Requ

este

d Ca

ndid

ate

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t

T_COMP

Both before and after the mobile sends the PSMM, the active pilots are the same and the candidate pilots are the same. The mobile patiently waits for the Extended Handoff Direction Message, which may cause some of the pilots to change sets.


Neig

hbor

Act

ive

Pilo

t

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

Unas

signe

d Ca

ndid

ate

54 102 134 200 248 300 328 396 416 420 488 504

T_ADD

T_DROP

-25

-20

-13

-3

-6

-10

0

-15

E C/I O

db.

IN CALL

Notice that PN396 has become Active, replacing PN328.

RECEIVEEHDM

Unas

signe

d Ca

ndid

ate

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Unas

signe

d Ca

ndid

ate

Act

ive

Pilo

t

Act

ive

Pilo

t

Act

ive

Pilo

t



Messages from a HandoffMessages from a Handoff


The Call is Already Established. What Next?E

c/Io

All PN Offsets

0

032K

512Chips

PN

0

-20

Neighbor Set

The call is already in progress. PN 168 is the only active signal,and also is our timing reference.

Continue checking the neighbors.

If we ever notice a neighbor with Ec/Io above T_ADD,ask to use it! Send a Pilot Strength Measurement Message!

T_ADD

Rake Fingers

Reference PN

Active Pilot

10752

16832002

50014080

220

! !

Mobile Rake RX

Srch PN??? W0

F1 PN168 W61F2 PN168 W61F3 PN168 W61


Mobile Requests the Handoff!

98/05/24 23:14:02.205 [RTC] Pilot Strength Measurement MessageMSG_LENGTH = 128 bitsMSG_TYPE = Pilot Strength Measurement MessageACK_SEQ = 5 MSG_SEQ = 0 ACK_REQ = 1ENCRYPTION = Encryption Mode DisabledREF_PN = 168 Offset Index (the Reference PN)PILOT_STRENGTH = -6.0 dBKEEP = 1PILOT_PN_PHASE = 14080 chips (PN220+0chips)PILOT_STRENGTH = -12.5 dBKEEP = 1PILOT_PN_PHASE = 32002 chips (PN500 + 2 chips)PILOT_STRENGTH = -11.0 dBKEEP = 1RESERVED = 0

PILOT STRENGTH MEASUREMENT MESSAGE

98/05/24 23:14:02.386 [FTC] Order MessageMSG_LENGTH = 64 bitsMSG_TYPE = Order MessageACK_SEQ = 0 MSG_SEQ = 0 ACK_REQ = 0ENCRYPTION = Encryption Mode DisabledUSE_TIME = 0 ACTION_TIME = 0ORDER = Base Station Acknowledgment OrderADD_RECORD_LEN = 0 bitsOrder-Specific Fields = Field Omitted RESERVED = 0


Just prior to this message, this particular mobile already was in handoff with PN 168 and 220. This pilot strength measurement message reports PN 500 has increased above T_Add, and the mobile wants to use it too.

The base station acknowledges receiving the Pilot Strength Measurement Message.


System Authorizes the Handoff!

98/05/24 23:14:02.926 [FTC] Extended Handoff Direction MessageMSG_LENGTH = 136 bitsMSG_TYPE = Extended Handoff Direction MessageACK_SEQ = 0 MSG_SEQ = 6 ACK_REQ = 1ENCRYPTION = Encryption Mode DisabledUSE_TIME = 0 ACTION_TIME = 0 HDM_SEQ = 0SEARCH_INCLUDED = 1 SRCH_WIN_A = 40 PN chipsT_ADD = -13.0 dB T_DROP = -15.0 dB T_COMP = 2.5 dBT_TDROP = 4 secHARD_INCLUDED = 0 FRAME_OFFSET = Field OmittedPRIVATE_LCM = Field Omitted RESET_L2 = Field OmittedRESET_FPC = Field Omitted RESERVED = Field OmittedENCRYPT_MODE = Field Omitted RESERVED = Field OmittedNOM_PWR = Field Omitted NUM_PREAMBLE = Field OmittedBAND_CLASS = Field Omitted CDMA_FREQ = Field OmittedADD_LENGTH = 0PILOT_PN = 168 PWR_COMB_IND = 0 CODE_CHAN = 61PILOT_PN = 220 PWR_COMB_IND = 1 CODE_CHAN = 20PILOT_PN = 500 PWR_COMB_IND = 0 CODE_CHAN = 50RESERVED = 0

HANDOFF DIRECTION MESSAGEThe base station sends a HandofDirection Message authorizing the mobile to begin soft handoff with all three requested PNs. The pre-existing link on PN 168 will continue to use Walsh code 61, the new link on PN220 will use Walsh Code 20, and the new link on PN500 will use Walsh code 50.

The mobile acknowledges it has received the Handoff Direction Message.

98/05/24 23:14:02.945 [RTC] Order MessageMSG_LENGTH = 56 bits MSG_TYPE = Order MessageACK_SEQ = 6 MSG_SEQ = 6 ACK_REQ = 0ENCRYPTION = Encryption Mode DisabledORDER = Mobile Station Acknowledgment OrderADD_RECORD_LEN = 0 bitsOrder-Specific Fields = Field Omitted RESERVED = 0



Mobile Implements the Handoff!

The mobile searcher quickly re-checks all three PNs. It still hears their pilots!

The mobile sends a Handoff Completion Message, confirming it still wants to go

ahead with the handoff.


98/05/24 23:14:02.985 [RTC] Handoff Completion MessageMSG_LENGTH = 72 bits MSG_TYPE = Handoff Completion MessageACK_SEQ = 6 MSG_SEQ = 1 ACK_REQ = 1ENCRYPTION = Encryption Mode DisabledLAST_HDM_SEQ = 0PILOT_PN = 168 Offset IndexPILOT_PN = 220 Offset IndexPILOT_PN = 500 Offset IndexRESERVED = 0

HANDOFF COMPLETION MESSAGE

The base station confirms it has received the mobile’s Handoff Completion message, and will continue with all of the links active.

98/05/24 23:14:03.085 [FTC] Forward Traffic Channel: Order ACK_SEQ: 0 MSG_SEQ: 1 ACK_REQ: 0 ENCRYPTION: 0 USE_TIME: 0 ACTION_TIME: 0 Base Station Acknowledgement Order


Neighbor List Updated, Handoff is Complete!

98/05/24 23:14:03.245 [RTC] Order MessageMSG_LENGTH = 56 bits MSG_TYPE = Order MessageACK_SEQ = 7 MSG_SEQ = 7 ACK_REQ = 0ENCRYPTION = Encryption Mode DisabledORDER = Mobile Station Acknowledgement OrderADD_RECORD_LEN = 0 bitsOrder-Specific Fields = Field OmittedRESERVED = 0


98/05/24 23:14:03.166 [FTC] Neighbor List Update MessageMSG_LENGTH = 192 bitsMSG_TYPE = Neighbor List Update MessageACK_SEQ = 1 MSG_SEQ = 7 ACK_REQ = 1ENCRYPTION = Encryption Mode DisabledPILOT_INC = 4 Offset IndexNGHBR_PN = 164 Offset IndexNGHBR_PN = 68 Offset IndexNGHBR_PN = 52 Offset IndexNGHBR_PN = 176 Offset IndexNGHBR_PN = 304 Offset IndexNGHBR_PN = 136 Offset IndexNGHBR_PN = 112 Offset IndexNGHBR_PN = 372 Offset IndexNGHBR_PN = 36 Offset IndexNGHBR_PN = 8 Offset IndexNGHBR_PN = 384 Offset IndexNGHBR_PN = 216 Offset IndexNGHBR_PN = 328 Offset IndexNGHBR_PN = 332 Offset IndexNGHBR_PN = 400 Offset IndexNGHBR_PN = 96 Offset IndexRESERVED = 0

NEIGHBOR LIST UPDATE MESSAGE

In response to the mobile’s Handoff Completion Message, the base station assembles a new composite neighbor list including all the neighbors of each of the three active pilots.This is necessary since the mobile could be traveling toward any one of these pilots and may need to request soft handoff with any of them soon.

The mobile confirms receiving the Neighbor List Update Message. It is

already checking the neighbor list and will do so continuously from now on.

The handoff is fully established.


Handoff Now In Effect, but still check Pilots!E

c/Io

All PN Offsets

0

032K

512Chips

PN

0

-20

Neighbor Set

Continue checking each ACTIVE pilot. If any are less than T_DROP and remain so for T_TDROP time, send Pilot Strength Measurement Message, DROP IT!!

Continue looking at each NEIGHBOR pilot. If any ever rises above T_ADD, send Pilot Strength Measurement Message, ADD IT!

T_ADD

Rake Fingers

Reference PN

Active Set

10752

16832002

50014080

220

T_DROP

Mobile Rake RX

Srch PN??? W0

F1 PN168 W61F2 PN500 W50F3 PN220 W20


The Complete Picture of Handoff & Pilot Sets

T_ADD

Ec/

IoAll PN Offsets

00

32K512

ChipsPN

0

-20

Neighbor Set

SRCH_WIN_N

Active Set

Candidate SetT_DROP

SRCH_WIN_A

Remaining SetT_ADD

SRCH_WIN_R

SRCH_WIN_A

T_DROP

Rake Fingers

Reference PN

Pilots of sectors now used for communication

Pilots requested by mobile but not set up by system

Pilots suggested by system for more checking

All other pilots divisible by PILOT_INC but not presently in Active, Candidate, or Neighbor sets

Mobile Rake RX

Srch PN??? W0

F1 PN168 W61F2 PN500 W50F3 PN220 W20


Deeper Handoff Details:Search Windows & TimingDeeper Handoff Details:

Search Windows & Timing

Section G


The Pilot Searcher’s Measurement Process

The searcher checks pilots in nested loops, much like meshed gears. Actives and candidatesoccupy the fastest-spinning wheel. Neighbors are next, advancingone pilot for each Act+Cand. revolution.Remaining is slowest, advancing one pilot each time the Neighbors revolve.

CURRENT PILOT SET CONTENTSA A A

C

N N N N N N N N N N N N

R R R R R R R R R R R R









R R R R

31

12112

PILOT SEARCHER VIEWED IN SEQUENCE: Typical Elapsed Time = 4 secondsA A A C N

R

A A A C A A A C A A A C A A A C A A A C A A A CN N N N N N

A A A C N A A A C A A A C A A A C A A A C A A A C A A A CN N N N N

A A A CN A A A C A A A C A A A C A A A C A A A C A A A CN N N N N N

N A A A C A A A C A A A CN N N R A A A C N A A A C A A A C A A AN N

C A A A C A A A CN N N

R

A A A C N A A A C A A A C A A AN N C A A AN

C A A A CN N Only 3 of 112 remaining set pilots have been checked thus far!

A

N

R

R

R

R

R

R

R

NN

N

N

NN N N

AA


A Quick Primer on Pilot Search WindowsThe phone chooses one strong sector and “locks” to it, accepting its offset at “face value”and interpreting all other offsets by comparison to itIn messages, system gives to handset a neighbor list of nearby sectors’ PNsPropagation delay “skews” the apparent PN offsets of all other sectors, making them seem earlier or later than expectedTo overcome skew, when the phone searches for a particular pilot, it scans an extra wide “delta” of chips centered on the expected offset (called a “search window”) Search window values can be datafilledindividually for each Pilot set:There are pitfalls if the window sizes are improperly set

• too small: overlook pilots from far away• too large: search time increases• too large: might misinterpret identity of a

distant BTS’ signal One chip is 801 feet or 244.14 m

1 mile=6.6 chips; 1 km.= 4.1 chips

PROPAGATION DELAYSKEWS APPARENT PN OFFSETS

BTSBTSA

B

33Chips

4 Chips

If the phone is locked to BTS A, thesignal from BTS B will seem 29 chipsearlier than expected.If the phone is locked to BTS B, thesignal from BTS A will seem 29 chipslater than expected.


Setting Pilot Search Window SizesWhen the handset first powers up, it does an exhaustive search for the best pilot. No windows are used in this process.On the paging channel, the handset learns the window sizes SRCH_WIN_A, N, R and uses them when looking for neighbors both in idle mode and during calls.When a strong neighbor is requested in a PSMM, the former neighbor pilot is now a candidate. Its offset is precisely remembered and frequently rechecked and tracked by the phone.Window size for actives and candidates can be small, since their exact position is known. Only search wide enough to include multipath energy!

• This greatly speeds up overall searching!Most post-processing tools deliver statistics on the spread (in chips) between fingers locked to the same pilot. These statistics literally show us how wide the SRCH_WIN_A should be set.Neighbor and Remaining search windows should be set to accommodate the maximum intercelldistances which a mobile might experience

SEARCH WINDOW SETTINGSAND PROPAGATION DISTANCES

Window Size (Chips)

14 (±7)

DatafillValue

N,R Delta Distance

4 1.0620 (±10)

40 (±20)28 (±14)

Miles KM.

56789101112131415

60 (±30)80 (±40)

100 (±50)130 (±65)160 (±80)226 (±113)320 (±160)452 (±226)

1.711.52 2.442.12 3.423.03 4.884.55 7.326.07 9.777.59 12.29.86 15.912.1 19.517.1 27.624.3 39.134.3 55.2


Handoff Problems: “Window” Dropped Calls

Calls often drop when strong neighbors suddenly appear outside the neighbor search window and cannot be used to establish soft handoff.Neighbor Search Window SRCH_WIN_N should be set to a width at least twice the propagation delay between any site and its most distant neighbor site Remaining Search Window SRCH_WIN_R should be set to a width at least twice the propagation delay between any site and another site which might deliver occasional RF into the service area

A

B

1 mi.7 Chips

BTS

BTS

SITUATION 1 Locked to distant site, can’t see

one nearby12 miles80 ChipsSRCH_WIN_N = 130BTS A is reference.BTS B appears (7-80) chipsearly due to its closer distance.This is outside the 65-chip window.Mobile can’t see BTS B’s pilot, but its strong signal blinds us and the call drops.

Travel

mountains

A

B

1 mi.7 Chips

BTS

BTS

SITUATION 2Locked to nearby

site, can’t see distant one12 miles80 Chips

Travel

SRCH_WIN_N = 130BTS B is reference.BTS A appears (80-7) chipslate due to its farther distance.This is outside the 65-chip window.Mobile can’t see BTS A’s pilot.

mountains


Overall Handoff Perspective

Soft & Softer Handoffs are preferred, but not always possible• a handset can receive BTS/sectors simultaneously only on one

frequency • all involved BTS/sectors must connect to a networked BSCs.

Some manufacturers do not presently support this, and so are unable to do soft-handoff at boundaries between BSCs.

• frame timing must be same on all BTS/sectorsIf any of the above are not possible, handoff still can occur but can only be “hard” break-make protocol like AMPS/TDMA/GSM

• intersystem handoff: hard• change-of-frequency handoff: hard• CDMA-to-AMPS handoff: hard, no handback

– auxiliary trigger mechanisms available (RTD)


Section I

Introduction to OptimizationIntroduction to Optimization


What is Performance Optimization?

The words “performance optimization” mean different things to different people, viewed from the perspective of their own jobsSystem Performance Optimization includes many different smaller processes at many points during a system’s life

• recognizing and resolving system-design-related issues (can’t build a crucial site, too much overlap/soft handoff, coverage holes, etc.)

• “cluster testing” and “cell integration” to ensure that new base station hardware works and that call processing is normal

• “fine-tuning” system parameters to wring out the best possible call performance

• identifying causes of specific problems and customer complaints, and fixing them

• carefully watching system traffic growth and the problems it causes - implementing short-term fixes to ease “hot spots”, and recognizing problems before they become critical


Performance Optimization Phases/Activities

hello

RF Design and Cell Planning

New Cluster Testing and

Cell Integration

Solve SpecificPerformance

Problems

Well-System Performance Management

Capacity Optimization

Growth Management:

Optimizing both Performance and Capital

Effectiveness

Cover desired area; have capacity for anticipated traffic

Ensure cells properly constructed and

configured to give normal performance

Identify problems from complaints or statistics; fix them!

Ensure present ‘plant’is giving best possible

performance

Manage congested areas for most

effective performance

Overall traffic increases and congestion;

competition for capital during tight times

Phase Drivers/Objectives Activities Main Tools Success Indicators

Plan cells to effectively cover as needed and divide traffic

load appropriately

Drive-test: coverage, all handoff boundaries, all call

events and scenarios

Detect, Investigate, Resolve performance problems

Watch stats: Drops, Blocks, Access Failures; identify/fix hot

spots

Watch capacity indicators; identify problem areas, tune parameters & configuration

Predict sector and area exhaustion: plan and validate effective growth plan, avoid

integration impact

Prop. Models,Test Transmitters,

planning tools Model results

Drive-test tools;cell diagnostics and

hardware test

All handoffs occur; all test cases

verified

Drive-test tools, system stats,

customer reports

Identified problems are

resolved

System statisticsAcceptable levels and good trends for all indicators

Smart optimization of parameters;

system statistics

Stats-Derived indicators; carried

traffic levels

Traffic analysis and trending tools;

prop. models for cell spliiting; carrier

additions

Sectors are expanded soon

after first signs of congestion;

capital budget remains within

comfortable bounds


Good Performance is so Simple!!

One, Two, or Three good signals in handoff• Composite Ec/Io > -10 db

Enough capacity• No resource problems – I’ve got what I

need

BTS BTS

BTS

Pilot

Paging

TrafficChannels

In use

availablepower

Sync

BTS

A

BTS

B

BTS

C

Ec/Io -10

FORWARDLINK


Bad Performance Has Many CausesWeak Signal / Coverage HolePilot Pollution

• Excessive Soft HandoffHandoff Failures, “Rogue” mobiles

• Missing Neighbors• Search Windows Too Small• BTS Resource Overload / No Resources

– No Forward Power, Channel Elements

– No available Walsh Codes– No space in Packet Pipes

Pilot “Surprise” ambush; Slow HandoffsPN Plan errorsSlow Data Problems: RF or IP congestionImproper cell or reradiator configurationHardware and software failuresBut on analysis, all of these problems’ bad effects happen because the simple few-signal ideal CDMA environment isn’t possible.

360

+41

+8

360+33cA

BBTS

BTS

BTS BPN 99

BTS APN 100

1 mile 11 miles

ACTIVE SEARCH WINDOW

xPilot

PagingSync

TrafficChannels

In Use

NoAvailablePower!B

TS Sector Transmitter

CEsVocodersSelectors

BTS Rx PwrOverload


Aeronautical Analogy: Tools for Problem Investigation

To study the cause of an aeronautical accident, we try to recover the Flight Data Recorder and the Cockpit Voice Recorder.

To study the cause of a CDMA call processing accident, we review data from the Temporal Analyzer and the Layer 3 Message Files -- for the same reasons.

Control & Parameters Messaging

BTS

1150011500

114.50118.25125.75

AeronauticalInvestigations

CDMAInvestigations

Flight Data Recorder Cockpit Voice Recorder

Temporal Analyzer Data Layer 3 Message Files


Starting Optimization on a New SystemRF Coverage Control

• try to contain each sector’s coverage, avoiding gross spillover into other sectors

• tools: PN Plots, Handoff State Plots, Mobile TX plotsSearch Window Settings

• find best settings for SRCH_WIN_A, _N, _R• especially optimize SRCH_WIN_A per sector using collected

finger separation data; has major impact on pilot search speedNeighbor List Tuning

• try to groom each sector’s neighbors to only those necessary but be alert to special needs due to topography and traffic

• tools: diagnostic data, system logsAccess Failures, Dropped Call Analysis

• finally, iterative corrections until within numerical goals

Getting these items into shape provides a solid baseline and foundation from which future performance issues can be addressed.


Solving Problems on Existing Systems

CDMA optimization is very different from optimization in analog technologies such as AMPS

AMPS: a skilled engineer with a handset or simple equipment can hear, diagnose, and correct many common problems

• co-channel, adjacent channel, external interferences• dragged handoffs, frequency plan problems

CDMA impairments have one audible symptom: Dropped Call• voice quality remains excellent with perhaps just a hint of garbling

even as the call approaches dropping in a hostile RF environment

Successful CDMA Optimization requires:• recognition and understanding of common reasons for call failure• capture of RF and digital parameters of the call prior to drop• analysis of call flow, checking messages on both forward and reverse

links to establish “what happened”, where, and why


CDMA Problems Attacked in Optimization

Excessive Access Failures• typical objectives: <2% (IS-95B will bring improvements)

Excessive Dropped Calls• typical objective: ~1%, <2%

Forward Link Interference• typical objective: eliminate situations which prevent handoff!

Slow Handoff• typical objective: eliminate situations which delay handoff!

Handoff Pilot Search Window Issues• avoid handoff drops!

Excessive Soft Handoff• control coverage, not T_Add/T_Drop, to manage soft handoff levels (~<50%)

Grooming Neighbor Lists• “if you need it, use it!”

Software Bugs, Protocol Violations• Neither system software, nor mobile software, nor the CDMA standard is

perfect. Don’t humbly accept problems -- dig in and find out what’s happening!


Sources of CDMA Data and Tools for Processing

CDMA optimization data flows from three places:• Switch• CDMA peripherals (CBSC & BTS)• Handset

Each stream of data has a family of software and hardware tools for collection and analysis

CBSCSwitch BTS

CDSU DISCO

Ch. Card ACC

ΣαΣβΣχ

TFU1GPSR

CDSUCDSU

DISCO 1DISCO 2


CDSUCDSUCDSUCDSUCDSUCDSU

CMSLM

LPP LPPENET

DTCs

DMS-BUS

Txcvr ATxcvr BTxcvr C

RFFE ARFFE BRFFE C

TFU1GPSR

IOC

BSM

Data AnalysisPost-Processing

Tools

IS-95/J-STD-008 Messages

IS-95/J-STD-8 Messages

Switch Datapegs, logs

Mobile DataPost-Processing

Tools

Mobile Data Capture Tools

HandsetMessages

ExternalAnalysis

Tools

PC-based

PC-based

Unix-based,PC-basedVarious

CDMA NETWORK EQUIPMENT HANDSET

System Internal Messages


Department Store Analogy: Tops-Down, Bottoms-Up

Some things are easier to measure from the customer side!

Complex!!! Simpler

System Phone

Neighbor ListsData Analysis

SoftwareTrans-

mission

Configuration

Provisioning

PSTN Trunking

Dropped Calls

CoverageAccess Failures

Switch

BTS

CBSC

InterferenceAdministration

Data CaptureField Tools

Profits

Complex!!! Simpler

Management Test Shopper

Labor Relations

Cost

sTaxe

s Insurance

Suppliers

Leases

Capital

Stocking

Distribution

Loss

esAdvertis

ing

Selection

ConveniencePrice

Service


Aeronautical Analogy: Tools for Problem Investigation

To study the cause of an aeronautical accident, we try to recover the Flight Data Recorder and the Cockpit Voice Recorder.

To study the cause of a CDMA call processing accident, we review data from the Temporal Analyzer and the Layer 3 Message Files -- for the same reasons.

Control & Parameters Messaging

BTS

1150011500

114.50118.25130.75

AeronauticalCase

CDMA Case

Flight Data Recorder Cockpit Voice Recorder

Temporal Analyzer Data Layer 3 Message Files


So S L O W ! ! Where’s My Data?!!

Some sessions are tormented by long latency and slow throughputWhere is the problem? Anywhere between user and distant host:

• Is the mobile user’s data device mis-configured and/or congested?• Is the BTS congested, with no power available to produce an SCH?• Poor RF environment, causing low rates and packet retransmission?• Congestion in the local IP network (PCU, R-P, PDSN FA)?• Congestion in the wireless operator’s backbone (‘OSSN’) network?• Congestion in the PDSN HA?• Congestion in the outside-world internet or Private IP network?• Is the distant host congested, with long response times?

IP D

ata

Envir

onm

entCDMA RF Environment

CDMA IOS PPPTraditional Telephony

IP Data Environment

t1t1 v CESEL

t1

R-P Interface

PDSN/Foreign Agent

PDSNHome Agent

BackboneNetworkInternet

VPNs

PSTN

T TSECURE TUNNELS

AuthenticationAuthorization

AccountingAAA

BTS

(C)BSC/Access ManagerSwitch WirelessMobile Device

•Coverage Holes•Pilot Pollution•Missing Neighbors•Fwd Pwr Ovld•Rev Pwr Ovld•Search Windows•Island Cells•Slow Handoff


Finding Causes of Latency and Low Throughput

IP network performance can be measured using test serversProblems between mobile a local test server? The problem is local

• check RF conditions, stats: poor environment, SCH blocking?• if the RF is clean, investigate BSC/PCU/R-P/PDSN-FA

Local results OK, problems accessing test server at PDSN-HA?• problem is narrowed to backbone network, or PDSN-HA

Results OK even through test server at PDSN-HA• then the problem is in the public layers beyond.

IP D

ata

Envir

onm

entCDMA RF Environment

CDMA IOS PPPTraditional Telephony

IP Data Environment

t1t1 v CESEL

t1

R-P Interface

PDSN/Foreign Agent

PDSNHome Agent


VPNs

PSTN

T TSECURE TUNNELS


AccountingAAA

BTS

(C)BSC/Access ManagerSwitch WirelessMobile Device

•Coverage Holes•Pilot Pollution•Missing Neighbors•Fwd Pwr Ovld•Rev Pwr Ovld•Search Windows•Island Cells•Slow Handoff

TestServer

TestServer

TestServer


Autonomous Data CollectionBy Subscriber Handsets

Autonomous Data CollectionBy Subscriber Handsets


Using Autonomous Collection

A Server downloads software to a large population of subscriber mobilesMobiles collect on custom profiles

• all or groups of mobiles can be enabled/disabled• new triggers can be rapidly developed and downloaded when desired

Mobiles upload compacted packets to server driven by custom triggers• may be immediately if needed, or at low-traffic pre-programmed times• collected data can include location/GPS/call event/L3

messaging/timestamps/etc.Server manages data, provides filtering and reportingPerformance optimizers use terminals and post-processing software

t1t1 vSELt1

R-P Interface

PDSN/Foreign Agent

PDSNHome Agent


VPNs

PSTN

T TSECURE TUNNELSAuthentication

AuthorizationAccounting

AAABTS

(C)BSC/Access ManagerSwitch

Collection Server•software download•collected data upload•data management, analysis

BTS

BTS

BTS


Conventional Field ToolsConventional Field Tools


CDMA Field Test ToolsField Collection Tools using Handset Data

There are many commercial CDMA field test toolsCharacteristics of many test tools:

• capture data from data ports on commercial handsets• log data onto PCs using proprietary software• can display call parameters, messaging, graphs, and maps• store data in formats readable for post-processing analysis• small and portable, easy to use in vehicles or even on foot

A few considerations when selecting test tools:• does it allow integration of network and mobile data?• Cost, features, convenience, availability, and support• new tools are introduced every few months - investigate!

QualcommMDM, CAIT

Grayson

Comarco

Willtech

EricssonTEMS

Motorola

PN Scanners

Agilent(HP + SAFCO)

Agilent(HP + SAFCO)

BerkeleyVaritronics

Grayson Qualcomm

DTI Willtech


Qualcomm’s MDM: Mobile Diagnostic Monitor

The Qualcomm Mobile Diagnostic Monitor was the industry’s first field diagnostic tool

• used industry-wide in the early deployment of CDMA

• pictures at right from Sprint’s first 1996-7 CDMA trials in Kansas City

Qualcomm’s Mobile Diagnostic Monitor • CDMA handset (customer provided)• Proprietary connecting cable• PC software for collection and field pre-

analysis– Temporal analyzer display mode– Messaging


Grayson’s Invex3G Tool

100 MB ethernet connection to PCthe eight card slots can hold receivers or dual-phone cardsthere’s also room for two internal PN scannersMultiple Invex units can be cascaded for multi-phone load-test applicationsCards are field-swappable -Users can reconfigure the unit in the field for different tasks without factory assistance


This mobile is in a 2-way soft handoff (two green FCH walsh codes assigned) in the middle of a downlink SCH burst. Notice walsh code #3, 4 chips long, is assigned as an SCH but only on one sector, and the downlink data speed is 153.6kb/s.

153.6kb/s

Grayson Invex 1x Data Example


F-SCH rates 153.6 kbps; R-SCH 76.8kbps

PN Scanner Data

Grayson Invex 1xData Example

Current Data Task StatusLayer-3 Messages

CDMA Status


WillTech Tools

Blue Rose platform can manage multiple phones and collect data

• Internal processor manages test operations independently for stand-alone operation

• Internal PCMCIA flash card provides storage

• An external PC can display collected data during or after data collection


Agilent Drive-Test Tools

Agilent offers Drive-Test tools• Serial interfaces for up to four

CDMA phones• A very flexible digital receiver

with several modesPN Scanner

• Fast, GPS-locked, can scan two carrier frequencies

Spectrum Analyzer• Can scan entire 800 or 1900

mHz. BandsBase-Station Over-Air Tester (BOAT)

• Can display all walsh channel activity on a specific sector

• Useful for identifying hardware problems, monitoring instantaneous traffic levels, etc.

Post-Processing tool: OPAS32


IS-95 Busy SectorSnapshot of Walsh Usage


1xRTT Busy SectorWalsh Code Usage


PN Scanners

Why PN scanners? Because phones can’t scan remaining set fast enough, miss transient interfering signalsBerkeley Varitronics

• high-resolution, GPS-locked– full-PN scan speed 26-2/3 ms.

• 2048 parallel processors for very fast detection of transient interferors

Agilent (formerly Hewlett-Packard)• high resolution, GPS-locked

– full-PN scan speed 1.2 sec.• Integrated with spectrum analyzer and

phone call-processing toolGrayson Wireless

• New digital receiver provides CDMA PN searcher and and sector walsh domain displays


Post-Processing Tools

Post-Processing tools display drive-test files for detailed analysis - Faster, more effective than studying data playback with collection tools aloneActix Analyzer

• Imports/analyzes data from almost every brand of drive-test collection tool

Andrew (formerly Grayson) Interpreter• Imports/analyzes data from Andrew Invex3G

Nortel RF Optimizer• Can merge/analyze drive-test and Nortel CDMA

system dataXceed Technologies Windcatcher

• Imports/analyzes data from almost every brand of drive-test device

Xceed Technologies Vortex• Provides automated analysis of data from manual,

autonomous, and stand-alone sourcesVerizon/Airtouch internal tool “DataPro”

Analyzer Interpreter

Windcatcher

Vortex


Maintenance Features of CDMA Handsets

Maintenance Features of CDMA Handsets

Drive-Tests: Phones


Handsets as Tools: Simple but always Available!

Most CDMA handsets provide some form of maintenance display (“Debug Mode”) as well as instrumentation access

• all CDMA drive-test tools use handsets as their “front-ends”Using the handset as a manual tool without Commercial Test Tools:

Enter the maintenance mode by special sequence of keystrokesDisplayed Parameters

• PN Offset, Handset Mode, Received RF Level , Transmit Gain AdjustMaintenance Display Applications

• best serving cell/sector• simple call debugging (symptoms of weak RF, forward link

interference, etc.)Handset Limitations during manual observation

• no memory: real-time observations only; no access to messages or call details; serving PN offset not updated during voice calls


Interpreting Samsung Maintenance Display:Acquisition, Idle, and Access States

Debug ScreenS04274 SI2 2T-56 D070-04P0060 CH0350PR6 RC0 0Z11

V206T144L:02

Reference PN Offset

0 - Pilot Channel Acquisition Substate1 - Sync Channel Acquisition Substate2 - MS Idle State3 - System Access State4 - Traffic Channel State5,6,7 - various call service options

Processing StateReceive Power,

dbm

Transmit Gain Adjust,

db

Display toggles between:System Identifier (SID)Network Identifier (NID)

Carrier Freq.(Channel #)

Ec/Io, db(primary PN only)

Slot Cycle Index

System ProtocolRevision Level

Packet Zone IDRadio Configuration(Idle mode = 0, 0)


Interpreting Samsung Maintenance Display:Traffic Channel State

Debug ScreenTE8 RE8 40 6T-10 D070-04P0060 CH0350PR6 RC33 Z11SO00003 G207F001.54%L:02

PN Offset

0 - Pilot Channel Acquisition Substate1 - Sync Channel Acquisition Substate2 - MS Idle State3 - System Access State4 - Traffic Channel State5,6,7 - various call service options

Processing StateReceive Power,

dbm

Transmit Gain Adjust,

db

Carrier Freq.(Channel #)

Ec/Io, db(primary PN only)

FCH Walsh Code

System ProtocolRevision Level

Packet Zone ID

Transmit (RL)Vocoder Rate

1 = 1/82 = 1/44 = 1/28 = Full

Receive (FL)Vocoder Rate

Radio Configuration(RC3, RC3 common)

Live CumulativeFER

Service Option


Denso Maintenance Display

CBV: 3957ABV: 3954 ABT: 031ARF: 0000 CCL: 01SID: 04157NID: 00001CH: 0100 RSSI: 093DPN: 084 TX:-46BFRM:0000000968TFRM:0000135712FER:% 000.71LT: 036:06:36LG: -086:45:36EC: -16 -63 -63PN: 084 084 084FNGLK: Y Y NWLSH: 01 01 01ACT: 084 484 096-01 -01 200CND: 220 332 200200 332 NGH: 076080 340 068 196O56 320 220 316344 488 196 200392 124 128 084224 008 084

DCharging Battery Voltage

Average Battery Voltage Average Battery Temperature

System IDNetwork ID

RF Channel FrequencyDigital PN Offset

Received Signal StrengthEstimated Transmitter

Power OutputNumber of Bad Frames

Number of Good Frames Frame Erasure Rate, PercentBase Station coordinates

Current status of Rake Fingers

Active Pilot Set

Candidate Pilot SetNeighbor Pilot Set


Sanyo SPC-4500 Maintenance Display

Choose the following:DISPLAYOK0OKEnter Code: 0 0 0 0 0 0Debug MenuSCREENOK


Sanyo SPC-4900 Maintenance Display

##040793select MENU/OK buttonscroll to save Phone #select

PN offset

Call Proc. StateReceivePower

Io

ChannelFrequency


Entering Maintenance Mode: Motorola StarTacContact your service provider to obtain your phone’s Master

Subscriber entity Lock (MSL). Then enter the following:FCN 000000 000000 0 RCL You'll be prompted for your MSL, enter it and press STO.

• New prompts will appear, Press STO in response to each prompt until no more appear. Don’t delay -continue quickly and enter:

FCN 0 0 * * T E S T M O D E STO • The display will briefly show US then just '.

Press 55#.• Step 1 will appear with its current setting displayed.

Press * to accept and move on to the next step. Repeat for steps 2-8.

Step 9 (Option byte 2) is the only step requiring manual changes. Enter 1 0 0 0 0 0 0 0 (The leftmost bit now set to '1' is what enables test mode.)Now press STO to accept the entry and exit back to the ' prompt.Power off and back on.You should now be in test mode!


RX Power BatteryCondition

N5 N5M failureBS BS Ack failureWO L3 WFO State TimeoutMP Max Probe FailurePC Paging Channel lossRR Reorder or Release on PCH?? Unknown Condition

ChannelNumber

#Neighbors

Local Time#

ActivesStrongest Active

PN Ec/IoStrongest NeighborPN Ec/Io

# Cand-idates Call Proc

StateLast Call

Exit Reason# Drops

# CallsLast Call FER%

NIDSIDRx Powerdbm (Io)

Tx Powerdbm

CurrentService Option

Last Call IndicatorNI No Indication yetMR Mobile ReleaseBR Base Sta. ReleaseTC Traffic Channel LostL2 Layer 2 Ack FailNC No Channel Assn Msg

Current Service Option8V 8K voice originalIL 8K loopback8EV 8K EVRC8S 8K SMS13L 13K loopback

13S 13K SMS8MO 8K Markov OldDAT Data8M 8K Markov New13M 13K Markov New13V 13K Voice

Call Processing StatesCP CP ExitRST CP RestartRTC RestrictedPLT Pilot AcquisitionSYN Sync AcquisitionTIM Timing ChangeBKS Background SchIDL IdleOVD OverheadPAG Paging

ORG Call OriginationSMS Short Message SvcORD Order ResponseREG RegistrationTCI Tfc Ch InitializationWFO Waiting for OrderWFA Waiting for AnswerCON Conversation stateREL ReleaseNON No State


Motorola V120C Series

MENU 073887* Enter 000000 for security code. Scroll down to Test Mode. Enter subscriber entity lock code if required by your phone

Same maintenance display as shown for Startac


Motorola V60C

MENU 073887* Enter 000000 for security code. Scroll down to Test Mode. Enter subscriber entity lock code if required by your phone

Same maintenance display as shown for Startac


Nokia 6185 Maintenance Display

Enter *3001#12345# MENUScroll down to Field testPress SelectScroll up to EnabledPress OKPower the phone off and onYou should now be in Field test mode


Novatel Merlin C201 1xRTT Data Card

Enter # # D E B U G to enter maintenance mode.To exit, just click “OK” box in the Debug window.


Audiovox Thera Maintenance Mode Screens

How to enterDebug Mode:

[ctrl] [D] [enter]

Advanced Usr Pwd:##DEBUG [enter]

Protocol Statistics


Sierra 580 1xEV-DO Rev 0 Aircard

To enter the maintenance display, hover your cursor over the Connection Manager main indicator window or the Start button and type “##debug”.

The Network, Network 2, and HDR tabs provide the most useful information on the air interface. The other tabs provide details of the packet operations and error counters.


What’s New in CDMA2000?What’s New in CDMA2000?

The Future is Here! CDMA2000


A Quick Survey of Wireless Data Technologies

This summary is a work-in-progress, tracking latest experiences and reports from all the high-tier (provider-network-oriented) 2G and 3G wireless data technologiesHave actual experiences to share, latest announced details, or corrections to the above? Email to [email protected]. Thanks for your comments!

AMPS Cellular9.6 – 4.8 kb/s

w/modem

IS-136 TDMA19.2 – 9.6 kb/s

GSM CSD9.6 – 4.8 kb/s

GSM HSCSD32 – 19.2 kb/s

IDEN19.2 – 19.2 kb/s

IS-9514.4 – 9.6 kb/s

IS-95B64 -32 kb/s

CDPD19.2 – 4.8 kb/sdiscontinued

GPRS40 – 30 kb/s DL

15 kb/s UL

EDGE200 - 90 kb/s DL

45 kb/s UL

1xRTT RC3153.6 – 80 kb/s

1xRTT RC4307.2 – 160 kb/s

1xEV-DO 02400 – 600 DL153.6 – 76 UL

1xEV-DO A3100 – 800 DL1800 – 600 UL

WCDMA 0384 – 250 kb/s

WCDMA 12000 - 800 kb/s

WCDMA HSDPA12000 – 6000 kb/s

Flarion OFDM1500 – 900 kb/s

TD-SCDMAIn Development

Mobitex9.6 – 4.8 kb/s

obsolete

WI-MAX

US CDMA ETSI/GSM

CELLULAR

PAGING

MISC/NEW1xEV-DV

5000 - 1200 DL307 - 153 UL


Modulation Techniques of 1xEV Technologies

1xEV, “1x Evolution”, is a family of alternative fast-data schemes that can be implemented on a 1x CDMA carrier.1xEV DO means “1x Evolution, Data Only”, originally proposed by Qualcomm as “High Data Rates” (HDR).

• Up to 2.4576 Mbps forward, 153.6 kbps reverse

• A 1xEV DO carrier holds only packet data, and does not support circuit-switched voice

• Commercially available in 20031xEV DV means “1x Evolution, Data and Voice”.

• Max throughput of 5 Mbps forward, 307.2k reverse

• Backward compatible with IS-95/1xRTT voice calls on the same carrier as the data

• Not yet commercially available; work continues

All versions of 1xEV use advanced modulation techniques to achieve high throughputs.

QPSKCDMA IS-95,

IS-2000 1xRTT,and lower ratesof 1xEV-DO, DV

16QAM1xEV-DOat highest

rates

64QAM1xEV-DVat highest

rates


DATA BURSTACTUALLY OCCURS

NOW

DA

TA R

ATE

DEC

ISIO

N

Fixed Rate!

1xRTT Data Burst Control Lags RF Conditions

BTS

MO

BIL

E

Tseconds

F-SCH

F-FCH

R-FCH

R-SCH

0 0.50.1 0.2 0.3 0.4

SCH-Assignment Msg.

F-SCH Burst

Setup Time

Path

Los

s, re

lativ

e dB

Eb/N

t, dB

Path Loss, db

GOOD CONDITIONS

BAD CONDITIONS

+6

+4

+2

+0

-2

0 0.1 0.2 0.3 0.4 0.5Time, Seconds


1xEV-DO vs. 1xRTT at the Same Time-Scale

T0 0.50.1 0.2 0.3 0.4

Time, Seconds

AP

Traffic

DRCSetup time can be less than 10 ms., depending on traffic loading. AT

1xEV-DO Thoughput: 2.4 Mb/s max, 0.6 Mb/s typ.

BTS

MO

BIL

E

F-SCH

F-FCH

R-FCH

R-SCHSCH-Request Msg.

SCH-Assignment Msg.

F-SCH Burst

Setup Time Fixed Rate!1xRTT

Thoughput: 0.15 or 0.31 Mb/s max, 0.06 Mb/s typ.


Channel Structure of 1xEV-DO vs. 1xRTTCHANNEL STRUCTURE

IS-95 and 1xRTT• many simultaneous users, each

with steady forward and reverse traffic channels

• transmissions arranged, requested, confirmed by layer-3 messages – with some delay……

1xEV-DO -- Very Different:• Forward Link goes to one user at a

time – like TDMA!• users are rapidly time-multiplexed,

each receives fair share of available sector time

• instant preference given to user with ideal receiving conditions, to maximize average throughput

• transmissions arranged and requested via steady MAC-layer walsh streams – very immediate!

BTS

IS-95 AND 1xRTTMany users’ simultaneous forward

and reverse traffic channelsW0W32W1W17W25W41

W3

W53

PILOTSYNC

PAGINGF-FCH1F-FCH2F-FCH3

F-SCH

F-FCH4

AP

1xEV-DO AP (Access Point)

ATs (Access Terminals)

1xEV-DO Forward Link


Power Management of 1xEV-DO vs. 1xRTT

POWER MANAGEMENTIS-95 and 1xRTT:

• sectors adjust each user’s channel power to maintain a preset target FER

1xEV-DO IS-856:• sectors always operate at

maximum power• sector output is time-

multiplexed, with only one user served at any instant

• The transmission data rate is set to the maximum speed the user can receive at that moment

PILOT

PAGINGSYNC

Maximum Sector Transmit Power

User 123

45 5 5678

time

pow

er

IS-95: VARIABLE POWER TO MAINTAIN USER FER

time

pow

er

1xEV-DO: MAX POWER ALWAYS,DATA RATE OPTIMIZED


Some EV-DO Terminology

Phone, Mobile,

Handset, or Subscriber Terminal

ATAccess

Terminal

Base Station,BTS,

Cell Site

APAccess Point

IS-95, IS-2000, 1xRTT EV-DO


1xEV-DO Technical DetailsData Flow and Channels

1xEV-DO Technical DetailsData Flow and Channels


1xEV-DO Transmission TimingForward Link

All members of the CDMA family - IS-95, IS-95B, 1xRTT, 1xEV-DO and 1xEV-DV transmit “Frames”

• IS-95, IS-95B, 1xRTT frames are usually 20 ms. long

• 1xEV-DO frames are 26-2/3 ms. long– same length as the short PN code– each 1xEV-DO frame is divided into

1/16ths, called “slots”The Slot is the basic timing unit of 1xEV-DO forward link transmission

• Each slot is directed toward somebody and holds a subpacket of information for them

• Some slots are used to carry the control channel for everyone to hear; most slots are intended for individual users or private groups

Users don’t “own” long continuing series of slots like in TDMA or GSM; instead, each slot or small string of slots is dynamically addressed to whoever needs it at the moment

One 1xEV-DO Frame

One Slot

One Cycle of PN Short Code


What’s In a Slot?

The main “cargo” in a slot is the DATA being sent to a userBut all users need to get continuous timing and administrative information, even when all the slots are going to somebody elseTwice in every slot there is regularly-scheduled burst of timing and administrative information for everyone to use

• MAC (Media Access Control) information such as power control bits

• a burst of pure Pilot– allows new mobiles to acquire the cell and decide to use it– keeps existing user mobiles exactly on sector time– mobiles use it to decide which sector should send them

their next forward link packet

SLOT DATA

MA

CPI

LOT

MA

C

DATA DATA

MA

CPI

LOT

MA

C

DATA

400 chips 64 96 64 400 chips 400 chips 64 96 64 400 chips

½ Slot – 1024 chips ½ Slot – 1024 chips


empty empty empty empty

What if there’s No Data to Send?

Sometimes there may be no data waiting to be sent on a sector’s forward link

• When there’s no data to transmit on a slot, transmitting can be suspended during the data portions of that slot

• But---the MAC and PILOT must be transmitted!!• New and existing mobiles on this sector and surrounding

sectors need to monitor the relative strength of all the sectorsand decide which one to use next, so they need the pilot

• Mobiles TRANSMITTING data to the sector on the reverse link need power control bits

• So MAC and PILOT are always transmitted, even in an empty slot

SLOT

MA

CPI

LOT

MA

C

MA

CPI

LOT

MA

C




Forward Link Frame and Slot Structure:“Big Picture” Summary

Slots make Frames and Frames make Control Channel Cycles!

SLOT

FRAME1 Frame = 16 slots – 32k chips – 26-2/3 ms

16 Frames – 524k chips – 426-2/3 ms

CONTROLCHANNEL USER(S) DATA CHANNEL

16-FRAMECONTROL CHANNEL

CYCLE

DATA

MA

CPI

LOT

MA

C

DATA DATA

MA

CPI

LOT

MA

C

DATA




EV-DO Rev. A Channels

The channels are not continuous like ordinary 1xRTT CDMANotice the differences between the MAC channels and the Rev. 0 MAC channels – these are the heart of the Rev. 0/A differences

IN THE WORLD OF CODES

Sect

or h

as a

Sho

rt P

N O

ffset

just

like

IS-9

5A

ccessLong PN

offsetPublic or Private

Long PN offset

ACCESS

FORWARD CHANNELS

AccessPoint(AP)

REVERSE CHANNELS

TRAFFIC

Pilot

Data

Primary Pilot

DataACK

Pilot

Control

Traffic

MAC

MAC

FORWARD

Rev ActivityDRCLockRPC

RRI

W 64

W264

W064

Wx16

Wx16

W1232

W12

W416

W016

W24

W016

MA

C

AccessTerminal

(UserTerminal)

Walshcode

Walshcode

Access Channelfor session setup

from Idle Mode

Traffic Channelas used duringa data session

ARQ Auxiliary Pilot

DRCDSC

W2832

W816

W1232


Sect

or h

as a

Sho

rt P

N O

ffset

just

like

IS-9

5

FORWARDCHANNELS

AccessPoint(AP)

Pilot

Control

Traffic

MAC

Rev ActivityDRCLockRPCW 64

W264

W064

Wx16

Wx16

MA

C

Walshcode

ARQ

Functions of Rev. A Forward Channels

•Access terminals watch the Pilot to select the strongest sector and choose burst speeds

•The Reverse Activity Channel tells ATs If the reverse link loading is too high, requiring rate reduction

Each connected AT has MAC channel:• DRCLock indication if sector busy• RPC (Reverse Power Control) • ARQ to halt reverse link subpackets as soon as complete packet is recovered

•The Control channel carries overhead messages for idle ATs but can also carry user traffic

•Traffic channels carry user data to one user at a time

DATA

MA

CPI

LOT

MA

C

DATA DATA

MA

CPI

LOT

MA

C

DATA

400 chips 64 96 64 400 chips 400 chips 64 96 64 400 chips½ Slot – 1024 chips ½ Slot – 1024 chips

Forward Link Slot Structure (16 slots in a 26-2/3 ms. frame)

AP


• Auxiliary Pilot on traffic channel allows synchronous detection during high data rates

Access

Long PN offset

Public or PrivateLong PN

offsetACCESS

REVERSE CHANNELS

TRAFFIC

Pilot

Data

Primary Pilot

DataACK

MAC RRI

W24

W016

AccessTerminal

(UserTerminal)

Walshcode

Access Channelfor session setup

from Idle Mode

Traffic Channelas used duringa data session

Auxiliary Pilot

DRCDSC

Functions of Rev. A Reverse Channels•The Pilot is used as a preamble during access probes

•Data channel during access carries mobile requests

• Primary Pilot on traffic channel allows synchronous detection and also carries the RRI channel

•RRI reverse rate indicator tells AP what rate is being sent by AT

•DRC Data Rate Control channel tells desired downlink speed

•ACK channel allows AT to signal successful reception of a packet

•DATA channel during traffic carries the AT’s traffic bits

•DSC Data Source Control channel tells which sector will send burst

W1232

W12

W416

W016

W2832

W816

W1232


Reverse Link Frame and Slot Structure:“Big Picture” Summary

Reverse Link frames are the same length as forward link framesThe mobile does not include separate MAC and Pilot bursts

• Its MAC and pilot functions are carried inside its signal by simultaneous walsh codes

There is no need for slots for dedicated control purposes since the mobile can transmit on the access channel whenever it needs

SLOT

FRAME1 Frame = 16 slots – 32k chips – 26-2/3 ms

DATA


1 Subframeholds

1 SubpacketSubframe Subframe Subframe


Rev. A Reverse Channel Sub-Frame Structure

The mobile transmits sub-packets occupying four reverse link slots, called a reverse link “sub-frame”.If multiple subpackets are required to deliver a packet, the additional subpackets are spaced in every third subframe until done

RRI

ACK DSC ACK DSC ACK DSC ACK DSC

DATA CHANNEL

DRC CHANNEL

AUXILIARY PILOT CHANNELPILOT CHANNEL

1 Sub-Frame

1 Slot 1 Slot 1 Slot 1 Slot


Information Flow Over 1xEV-DO

The system notifies a mobile when data for it is waiting to be sentThe mobile chooses which sector it hears best at that instant, and requests the sector to send it a packetthere are 16 possible transmission formats the mobile may request, called “DRC Indices”. Each DRC Index value is really a combined specification including specific values for:

• what data speed will be transmitted• how big a “chunk” of waiting data will be sent (that amount of data will be

cut of the front of the waiting data stream and will be the “Packet”transmitted)

• what kind of encoding will be done to protect the data (3x Turbo, 5x Turbo, etc.) and the symbol repetition, if any

• after the symbols are formed, how many SUBpackets they will be divided into

Then, the sector starts transmitting the SUBpackets in SLOTS on the forward linkThe first slot will begin with a header that the mobile will recognize so it can begin the receiving process

AP

Data Ready

DRC: 5

Data from PDSN for the Mobile

MP3, web page, or other content


Transmission of a Packet over EV-DO

AP

Data Ready

A user has initiated a1xEV-DO data session on their AT, accessing a favorite website.The requested page has just been received by the PDSN.The PDSN and Radio Network Controller send a “Data Ready” message to let the AT know it has data waiting.

The AT quickly determines which of its active sectors is the strongest. On the AT’s DRC channel it asks that sector to send it a packet at speed “DRC Index 5”.

The mobile’s choice, DRC Index 5, determines everything:The raw bit speed is 307.2 kb/s.The packet will have 2048 bits.There will be 4 subpackets (in slots 4 apart).The first subpacket will begin with a 128 chip preamble.

DRC: 5

DRCIndex Slots Preamble

ChipsPayload

BitsRawkb/s

0x0 n/a n/a 0 null rate0x1 16 1024 1024 38.40x2 8 512 1024 76.80x3 4 256 1024 153.60x4 2 128 1024 307.20x5 4 128 2048 307.20x6 1 64 1024 614.40x7 2 64 2048 614.40x8 2 64 3072 921.60x9 1 64 2048 1,228.80xa 2 64 4096 1,228.80xb 1 64 3072 1,843.20xc 1 64 4096 2,457.60xd 2 64 5120 1,536.00xe 1 64 5120 3,072.0

C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3

in Rev. Ain Rev. A

Modu-lationQPSKQPSKQPSKQPSKQPSKQPSKQPSKQPSKQPSKQPSK

16QAM8PSK

16QAM16QAM16QAM

Data from PDSN for the Mobile

MP3, web page, or other content


Transmission of a Packet over EV-DOData from PDSN for the Mobile

MP3, web page, or other content AP

Data Ready

DRC: 5

2048 bits

Interleaver

+ D+

+D D

++ +

+

+ D+

+D D

++ +

+

Turbo Coder

PACKET

Symbols

Using the specifications for the mobile’s requested DRC index, the correct-size packet of bits is fed into the turbo coder and the right number of symbols are created.


ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3

in Rev. Ain Rev. A


16QAM8PSK

16QAM16QAM16QAM




Data Ready

DRC: 5

2048 bits

Interleaver

+ D+

+D D

++ +

+

+ D+

+D D

++ +

+

Turbo Coder

Block Interleaver

PACKET

Symbols


To guard against bursty errors in transmission, the symbols are completely “stirred up” in a block interleaver.


ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3

in Rev. Ain Rev. A


16QAM8PSK

16QAM16QAM16QAM




Data Ready

DRC: 5

2048 bits

Interleaver

+ D+

+D D

++ +

+

+ D+

+D D

++ +

+

Turbo Coder

Block Interleaver

PACKET

Symbols

Interleaved Symbols


To guard against bursty errors in transmission, the symbols are completely “stirred up” in a block interleaver.

The re-ordered stream of symbols is now ready to transmit.


ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3

in Rev. Ain Rev. A


16QAM8PSK

16QAM16QAM16QAM




Data Ready

DRC: 5

2048 bits

1 2 3 4

Interleaver

+ D+

+D D

++ +

+

+ D+

+D D

++ +

+

Turbo Coder

Block Interleaver

PACKET

SLOTS

Symbols

Interleaved Symbols

When the AP is ready, the first subpacket is actually transmitted in a slot.

The first subpacket begins with a preamble carrying the user’s MAC index, so the user knows this is the start of its sequence of subpackets, and how many subpackets are in the sequence..

The user keeps collecting subpackets until either:

1) it has been able to reverse-turbo decode the packet contents early, or

2) the whole schedule of subpackets has been transmitted.

Subpackets


ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3

in Rev. Ain Rev. A


16QAM8PSK

16QAM16QAM16QAM


DATA MAC

PILO

T

MAC DATA DATA MAC

PILO

T

MAC DATA

336 chips 64 96 64 400 chips 400 chips 64 96 64 400 chips½ Slot – 1024 chips ½ Slot – 1024 chips

PRBL

64

Example Subpacket: 1536 Data Modulation Symbols (1 slot, 614.4 Kb/s)

1/3 or 1/5encoder

scrambler

ChannelInterleaver

QPSK/8PSK16QAM

Modulator

SequenceRepetition,

SignalPuncturing

SymbolDEMUX1 to 16

16-aryWalshCovers

WalshChannel

Gain

WalshChip LevelSummer

Data(modulation

symbols)SequenceRepetition 0

I

Q

I

Q

32-symbol bi-OrthogonalMAC cover

SignalPoint

Mapping

SequenceRepetition(factor=4)

I

Q

WalshChip LevelSummer Q

RAchannel

gain

SignalPoint

Mapping

BitRepetition(xRAB len)

MAC channelRA bits

DRC LockChannel

Gain

RPCChannel

Gain

SignalPoint

Mapping

SignalPoint

Mapping

BitRepetition(xDRCLlen)

Walsh Cover W264

MAC Index Walsh CoverMAC RPC bits A

MAC channelDRC Lock symbols

0

I

Q

Walsh Cover 0

SignalPoint

MappingPilot Channel (all 0s)

TDM

Time D

ivision Multiplexer

To Quadrature Spreading and M

odulationI W

alsh Channels

Q W

alsh Channels

I

Preamble

One Slot on the Forward Traffic Channel


The MAC Index

Each active user on a sector is assigned a unique 7-bit MAC index (64 MACs possible)Each data packet begins with a preamble, using the MAC index of the intended recipientFive values of MAC indices are reserved for “multi-user” packets

• packets intended for reception by a group– for example, control channels

• mobiles may have individual MAC indices AND be simultaneously in various groups

• this “trick” keeps payload size low even for transmissions to groups

MAC Channel Use Preamble UseNot Used Not UsedNot Used 76.8 kbps CCHNot Used 38.4 kbps CCH

RA Channel Not UsedAvailable for RPC

and DRCLockChannel

Transmissions

Available forForward

Traffic ChannelTransmissions

MACIndex0 and 1

234

5-63

MA

CIn

dex

Wal

sh C

ode

Phas

e

32 16 I

MA

CIn

dex

Wal

sh C

ode

Phas

e

1 32 Q34 17 I 3 33 Q36 18 I 5 34 Q38 19 I 7 35 Q40 20 I 9 36 Q42 21 I 11 37 Q44 22 I 13 38 Q46 23 I 15 39 Q48 24 I 17 40 Q50 25 I 19 41 Q52 26 I 21 42 Q54 27 I 23 43 Q56 28 I 25 44 Q58 29 I 27 45 Q60 30 I 29 46 Q62 31 I 31 47 Q

MA

CIn

dex

Wal

sh C

ode

Phas

e

0 0 I2 1 I4 2 I6 3 I8 4 I

10 5 I12 6 I14 7 I16 8 I18 9 I20 10 I22 11 I24 12 I26 13 I28 14 I30 15 I

MA

CIn

dex

Wal

sh C

ode

Phas

e

33 48 Q35 49 Q37 50 Q39 51 Q41 52 Q43 53 Q45 54 Q47 55 Q49 56 Q51 57 Q53 58 Q55 59 Q57 60 Q59 61 Q61 62 Q63 63 Q

AP


Rev. A MAC Index Values and Their Uses

114 MAC indices are available for regular single-user packets3 MAC indices are earmarked for control channel packets5 MAC indices are reserved for mult-user packets1 MAC index is reserved for broadcast packets, or single-users4 MAC indices are not used due to conflicts with multiplexing patterns


Rev. A MAC Index and I/Q Channel Contents


Link Rates and Packet/Subpacket Formats

The 1xEV-DO Rev. A reverse link has seven available modes offering higher speeds than available in Rev. 0

• Modulation formats are hybrids defined in the standardThe 1xEV-DO Rev. A forward has two available modes offering higher speeds than available in Rev. 0.

FORWARD LINK REVERSE LINKDRCIndex Slots Preamble

ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3+8.3+11.3


16QAM8PSK

16QAM16QAM16QAM

PayloadBits128256512768102415362048307240966144819212288

Modu-lation

B4B4B4B4B4Q4Q4Q2Q2

Q4Q2Q4Q2E4E2

Effective Rate kbps after:4 slots

184312289216144613072301531157638

19.28 slots

92161446130723015311576.857.638.419.29.6

12 slots

614409307

204.8153.6102.476.851.238.425.612.86.4

16 slots

460.8307.2230.4153.6115.276.857.638.428.819.29.64.8

Code Rate (repetition) after4 slots 8 slots 12 slots16 slots

1/5 1/5 1/5 1/51/5 1/5 1/5 1/51/4 1/5 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/51/2 1/4 1/5 1/52/3 1/3 2/9 1/52/3 1/3 1/3 1/3


The Hybrid ARQ Process

In 1xRTT, retransmission protocols typically work at the link layer

• Radio Link Protocol (RLP)– communicates using

signaling packets– lost data packets aren’t

recognized and are discarded at the decoder

This method is slow and wasteful!

SYSTEM

MAClayer

Physicallayer

RLP RadioLink Protocol

Application layer

LAC layer

MAClayer

Physicallayer

RLP RadioLink Protocol

CDMA2000 1xRTT

F-FCHR-FCH

Application layer

LAC layer

Application layer

Stream layer

Session layer

Connection layer

Security layer

MAC layer

Physicallayer

HARQprotocol

AP Access Point AT Access TerminalCDMA2000 1xEV-DO

Physicallayer

HARQprotocol

R-ACK

Application layer

Stream layer

Session layer

Connection layer

Security layer

MAC layer

F-TFC repeats

In 1xEV-DO, RLP functions are replicated at the physical layer

• HARQ Hybrid Repeat Request Protocol– fast physical layer ACK bits– Chase Combining of multiple

repeats– unneeded repeats pre-empted

by positive ACKThis method is fast and efficient!


The Hybrid ARQ Process

Each physical layer data packet is encoded into subpackets• as long as the receiver does not send back an

acknowledgment, the transmitter keeps sending more subpackets, up to the maximum of the current configuration

• The identity of the subpackets is known by the receiver, so it can combine the subpackets for better decoding

each additional subpacket in essence contributes additional signal power to aid in the detection of its parent packet

• it’s hard to predict the exact power necessary for successful decoding in systems without HARQ

– the channel changes rapidly during transmission– various estimation errors (noise, bias, etc.)– exact needed SNR is stochastic, even on a static channel!

In effect, HARQ sends progressively more energy until there is just enough and the packet is successfully decoded


Packet 0Subpackets

Multiple ARQ Instances

Definition: Number of ARQ Instances• the maximum number of packets that may be in transit simultaneously• sometimes also called “the number of ARQ channels”

This figure and the preceding page appear to show 4 ARQ instancesPackets in the different ARQ instances

• may be for the same user (the most common situation)• may be for different users (determined by QOS and scheduling)

Destination mobile knows its packets by their preamble

0 1 2 3Data

PacketsEncoding

andScrambling

Inter-leaving

bits symbols

PacketSubpacket

00

1.0

01

02

03

2.0

3.0

1.1

2.1

3.1

1.2

2.2

3.2

1.3

2.3

3.3

One Slot

Forward

ChannelTraffic

A


Packet 0Subpackets






0 1 2 3Data

PacketsEncoding

andScrambling

Inter-leaving

bits symbols

PacketSubpacket

00

1.0

01

02

03

2.0

3.0

1.1

2.1

3.1

1.2

2.2

3.2

1.3

2.3

3.3

One Slot

Forward

ChannelTraffic

Packet 1Subpackets

0 1 2 3

A


Packet 0Subpackets






0 1 2 3Data

PacketsEncoding

andScrambling

Inter-leaving

bits symbols

PacketSubpacket

00

1.0

01

02

03

2.0

3.0

1.1

2.1

3.1

1.2

2.2

3.2

1.3

2.3

3.3

One Slot

Forward

ChannelTraffic

Packet 1Subpackets

0 1 2 3

Packet 2Subpackets

0 1 2 3

A


Packet 0Subpackets






0 1 2 3Data

PacketsEncoding

andScrambling

Inter-leaving

bits symbols

PacketSubpacket

00

1.0

01

02

03

2.0

3.0

1.1

2.1

3.1

1.2

2.2

3.2

1.3

2.3

3.3

One Slot

Forward

ChannelTraffic

Packet 1Subpackets

0 1 2 3

Packet 2Subpackets

0 1 2 3

Packet 3Subpackets

0 1 2 3


1xEV-DO Rev. A1xEV-DO Rev. A


1xEV-DO Rev. A Design Objectives

To enable multimedia services• high-speed upload of multimedia files and attachments • interactive gaming• IP-based services such as Voice over Internet Protocol (VoIP).

To allow real-time conversational services• push to talk, • video telephony • instant multimedia -- an extension of push to talk that combines

immediate voice with simultaneous delivery of video and pictures. multimedia multicasting using QUALCOMM's “Platinum Multicast”

• enables high-quality video/audio to many users simultaneously.Peak forward link data rates of 3.1 Mbps Peak reverse link data rates of 1.8 Mbps Optimized packet data service

• one of lowest costs per bit compared to other wireless technologies.


Forward Link Enhancements in 1xEV-DO Rev. A

Forward Link Enhancements• Peak rates increased from 2.4 Mbps to 3.1 Mbps• Multi-user packet support• Small payload sizes (128, 256, 512 bits) improve frame fill efficiency• The DRC channel functions are broken out into two channels

– DRC retains rate control indication– new Data Source Control (DSC) Channel shows desired serving cell

• Minimizes interruptions due to server switching on FL


Reverse Link Enhancements in 1xEV-DO Rev. A

Reverse Link Enhancements• Higher data rates and finer quantization

• Data rates from 4.8 kbps to 1.8 Mbps with 48 payload sizes• 4 slots/sub-packets regardless of payload size (6.66 ms)• Modulation:

– Low rates: 1 walsh channel, BPSK modulation– Medium rates: 1 walsh channel, QPSK modulation– High Rates: 2 walsh channels, QPSK modulation– Highest Rate: 2 walsh channels, 8PSK modulation

• Hybrid ARQ using fast re-transmission (re-tx) and early termination• Flexible rate allocation: each AT has autonomous and scheduled mode• Efficient VOIP support• 3-channel synchronous stop-and-wait protocol• The mobile can use higher power and finish earlier when transmitting

packets of applications requiring minimum latency


Available Link Rates in 1xEV-DO Rev. A

The 1xEV-DO Rev. A reverse link has seven available modes offering higher speeds than available in Rev. 0

• Modulation formats are hybrids defined in the standardThe 1xEV-DO Rev. A forward has two available modes offering higher speeds than available in Rev. 0.

FORWARD LINK REVERSE LINKDRCIndex Slots Preamble

ChipsPayload

BitsRawkb/s


C/Idbn/a

-11.5-9.2-6.5-3.5-3.5-0.6-0.5+2.2+3.9+4.0+8.0+10.3+8.3+11.3


16QAM8PSK

16QAM16QAM16QAM

PayloadBits128256512768102415362048307240966144819212288

Modu-lation

B4B4B4B4B4Q4Q4Q2Q2

Q4Q2Q4Q2E4E2

Effective Rate kbps after:4 slots

184312289216144613072301531157638

19.28 slots

92161446130723015311576.857.638.419.29.6

12 slots

614409307

204.8153.6102.476.851.238.425.612.86.4

16 slots

460.8307.2230.4153.6115.276.857.638.428.819.29.64.8

Code Rate (repetition) after4 slots 8 slots 12 slots16 slots

1/5 1/5 1/5 1/51/5 1/5 1/5 1/51/4 1/5 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/53/8 1/5 1/5 1/51/2 1/4 1/5 1/51/2 1/4 1/5 1/52/3 1/3 2/9 1/52/3 1/3 1/3 1/3


What’s Next? 1xEV-DO Rev. B

CDG says 1Q06 for Rev. BTelecoms.com News17 November 2005Rufus Jay, [email protected]

The CDMA Development Group (CDG) has announced that the EV-DO Revision B standard is pencilled in for release in 1Q06. Rev. B increases data throughput to 73.5Mbps in the forward linkand 27Mbps in the reverse link. As well as supporting mobile broadband data and OFDM based multicasting, Rev. B's lower latency rates will improve the performance of VoIP, push to talk over cellular, video calling, concurrent voice and multimedia and multiplayer online gaming. The CDG also plans to expand cdma2000 by improved roaming and a sub US$40 handset push, similar to the GSMA's emerging markets initiative.


1xEV-DO Network Architecture1xEV-DO Network Architecture


CDMA Network for Circuit-Switched Voice Calls

The first commercial IS-95 CDMA systems provided only circuit-switched voice calls

t1t1 v CESEL

t1PSTN

BTS



CDMA 1xRTT Voice and Data Network

CDMA2000 1xRTT networks added two new capabilities:• channel elements able to generate and carry independent streams of

symbols on the I and Q channels of the QPSK RF signal– this roughly doubles capacity compared to IS-95

• a separate IP network implementing packet connections from the mobile through to the outside internet

– including Packet Data Serving Nodes (PDSNs) and a dedicated direct data connection (the Packet-Radio Interface) to the heart of the BSC

The overall connection speed was still limited by the 1xRTT air interface

t1t1 v CESEL

t1

PDSNForeign Agent

PDSNHome Agent


VPNs

PSTN


AccountingAAA

BTS



1xEV-DO Overlaid On Existing 1xRTT Network

1xEV-DO requires faster resource management than 1x BSCs can give• this is provided by the new Data Only Radio Network Controller (DO-RNC)

A new controller and packet controller software are needed in the BTS to manage the radio resources for EV sessions

• in some cases dedicated channel elements and even dedicated backhaul is used for the EV-DO traffic

The new DO-OMC administers the DO-RNC and BTS PCF additionExisting PDSNs and backbone network are used with minor upgradingThe following sections show Lucent, Motorola, and Nortel’s specific solutions

t1t1 v CESEL

t1

PDSNForeign Agent

PDSNHome Agent


VPNs

PSTN


AccountingAAA

BTS

(C)BSC/Access ManagerSwitch CE

DORadio

NetworkController

DO-OMC


Lucent 1xEV-DO ArchitectureLucent 1xEV-DO Architecture


Lucent 1xEV-DO Radio Access Network (RAN)

A Lucent 1xEV-DO Radio Access Network (RAN) includes• 1xEV-DO base stations and the• 1xEV-DO Flexent® Mobility Server (FMS).

The 1xEV-DO equipment may be collocated with IS-95 and/or 1xRTT equipment, creating 1xEV-DO/IS-95 and 1xEVDO/3G-1X combination base stations.

T-1/E-1Ethernet

RF

Internet

AAAServer

AP

OMP FXElement Management

System

Router

FlexentMobilityServer

DownlinkInput

Router

DownlinkInput

Router

UplinkInput

Router

UplinkInput

Router

FlexentMobilityServer

PacketData

ServingNode

(PDSN)

User ATs(Access Terminals)

RFAP

AP

AP


1xEV-DO in Lucent Flexent Mod Cell Cabinets

Lucent Mod Cell cabinets can support up to three IS-95 or 1xRTT carriers on three sectors1xEV-DO CDMA Digital Modules (CDM) can be mixed with conventional CDMs in the same cabinetthe same RF hardware (filters, amplifiers, other RF components) can be used for IS-95, 1xRTT, and 1xEV-DO


Lucent CDMA Digital Module (CDM) Configurations

At upper left is a CDM for conventional IS-95 / 1xRTT service. It includes

• CRC CDMA Radio controller• up to 6 CCU CDMA Channel Units• PCU power converter module• CBR CDMA Baseband Radio

At lower left is a CDM for 1xEV-DO• it must be occupy the leftmost slot• all CCU packs are removed and

replaced by a single 1xEV-DO modem (EVM) occupying 2 slots

• the CRC must be 44WW13D or later


1xEV-DO in Lucent Mod Cell 4.0 CabinetsThe Mod Cell 4 cabinet comes in many variationsInstead of per-carrier dedicated CDMs, resources are pooledURCs (Universal Radio Controllers) are used to steer data for each carrier to EVMs for EVDO or CMUs for IS-95/1xRTT.

• in a mixed-mode system, a URC is required for EVDO and a URC for IS-95/1xRTT

The modulated signal from a 4.0 EVM or CMU is upconverted to the RF carrier frequency by the UCR

• each UCR (Universal CDMA Radio) can handle up to three carriers

UniversalRadio

Controller(URC) Evolution

Modem(4.0 EVM) Universal

CDMARadio(UCR)CDMA

ModemUnit

(CMU)Universal

RadioController

(URC)ECP

FMS

Antenna

Carr1

Carr2, 3

Digital Shelf Flow


Lucent 1xEV-DO Flexent Mobility Server (FMS)

The Flexent Mobility Server is the heart of the Radio Access NetworkIt provides four processors running the 1xEV-DO Application Processor (DO-AP), which provides the Packet Controller Function (PCF)The PCF provides air link and radio resource management to implement 1xEV-DO user sessions, including the dormant state and other DO-specific features


Motorola 1xEV-DO ArchitectureMotorola 1xEV-DO Architecture


Motorola 1xEV-DO System Architecture

New 1xEV-DO carrier appears as a standard carrier addition to existing network elements

• new MCC-DO cards and OMC-R database revisions needed• AAA and PDSN need software upgrades

MSC

MM/SDU

OMC-IP

OMC-R 1x-AN

1x-BTS

OMC-DO

BSC-DO

AN-DO

MCC-DO

AAAAN-AAA

PDSNs

HAsPacket CoreNetwork

VPU

1xEV-DOIS-95/1xShared 1x/DO

ConnectionsElementsExisting IS-95New 1xEV-DOShared IS-95/DO


New Motorola 1xEV-DO Network Elements

MCC-DO (Multi-Channel Controller - Data Only)AN-DO (Access Node - Data only)

• CR (Consolidation Router) Similar in function to the 1x-AN MGX • LSW (Layer 3 Switch) Similar in function to the 1x-AN CATs

BSC-DO (Base Station Controller-Data Only)• Mobility functions like 1x MM - Packet Control & Selection – like SDU

OMC-DO (Operations & Maintenance Center - Data Only)LMT (Local Maintenance Terminal)

MSC

MM/SDU

OMC-IP

OMC-R 1x-AN

1x-BTS

OMC-DO

BSC-DO

AN-DO

MCC-DO

AAAAN-AAA

PDSNs

HAsPacket CoreNetwork

VPU

1xEV-DOIS-95/1xShared 1x/DO

ConnectionsElementsExisting IS-95New 1xEV-DOShared IS-95/DO


Motorola 1xEV-DO Block Diagramand Network Upgrade Summary

IS-2000 1xEV-DOTool LMF LMT

MCC-1XGLI (Traffic)

AN (MGX8800) CRAN (Catalyst 6509) LSW

BSC CBSC BSC-DOOMC-R

UNOIP Network

Telephone Network MSC/HLR Not RequiredData Network Not Required AAA

BTS frame & CCP shelf

BTS

PDSN (Note 1)

GLI (Control)

MCC-DO

OMC-DO

AN

O&M

LPABBX-1X

CR

BSC-DO

PDSN

OMC-DO

LSW

BTS

RF

Fron

t End

1x Modems

DO BBX

1x BBX

MCC-DO

AN-AAA

BTSR

F Fr

ont E

nd

1x Modems

DO BBX

1x BBX

MCC-DO

T1 or E1

AN-DO


Motorola MCC-DO Functions

1xEV-DO Modem• 1 carrier, 3 sectors per

MCC-DO card• Supports 59 channels per

sectorSpan Interface

• Up to 3 Active Span lines per MCC-DO

• Most operators will generally deploy with 2 spans per BTS

BTS provides control:• SCAP messaging• Redundant BBX Selection• Enhanced BBX interface

CR

BSC-DO

PDSN

OMC-DO

LSW

BTSR

F Fr

ont E

nd

1x Modems

DO BBX

1x BBX

MCC-DO

AN-AAA

BTS

RF

Fron

t End

1x Modems

DO BBX

1x BBX

MCC-DO

T1 or E1

AN-DO

MCC- DO


Nortel 1xEV-DO ArchitectureNortel 1xEV-DO Architecture


A Typical Nortel CDMA2000 SystemProviding 1xRTT Voice, Data, and 1xEV-DO


Nortel Multiple Backhaul and Configuration Possibilities


Nortel Univity® Indoor Metrocell

Univity® Metro Cell can support:

• up to six CDMA 1.25 MHz carrier frequencies

• up to three sectors. High Power Amplifiers and Low Noise Amplifiers are housed in an external unit

• the Multi-Carrier Flexible Radio Module (MFRM)

• MFRM may be mast mounted to improve AP RF link budget

Univity® CDMA Metro Cell Indoor Base Transceiver System (AP)


Nortel DOM: Data-Only Module

The Data Only Module (DOM) adds 1xEV-DO capability to a MetroCell AP CEM shelf

• transmits/receives baseband data to/from the digital control group (DCG) in the CORE module

• CORE switches baseband to proper carrier on the MFRM for transmission

• the DOM performs all encoding/decoding of IP packets for transport on data-only network to the Data-Only Radio Network Controller (DO-RNC)

• One DOM supports up to a three-sector, one-carrier MetroCell AP

• Additional DOMs support additional carriers


Nortel’s DO-RNCThe Data-Only Radio Network Controller

DO-RNC is the heart of a 1xEV-DO network, located at the central office (CO) with the BSC and/or BSS Manager (BSSM)DO-RNC is a stand-alone node supporting 1xEV-DO. It manages:

• DOMs at multiple APs (even on different band classes) over IP-based backhaul network

• access terminal state, both idle and connected

• handoffs of ATs between cells and carrier frequencies (reverse); sector selection (fwd).

• connections from airlink to PDSN over standard A10-A11 interfaces

• connects to MetroCell AP via dedicated IP backhaul network

DO-RNC is the peer of the access terminal for most over-the-air signaling protocols, including session and connection layers

Nortel DO-RNCData-Only

Radio Network Controller


An EV-DO Connection

CONTROL

MAC

PILOT

TRAFFIC

AccessPoint(AP)

ACCESS

TRA

FFIC

PILOTRRIDRCACK

DATA

AccessTerminal

(AT)

Rake Receiver#1 PN168+0 W23

#2 PN168+2 W23

#3 PN168+9 W23

#4 PN168+5 W23

Pilot Searcher

CONNECTION REQUESTCONNECTION ROUTE UPDATE

MAC ACKTRAFFIC CHANNEL ASSIGNMENT

MAC RTC ACKTRAFFIC CHANNEL COMPLETE

XON REQUEST

NEIGHBOR LISTXON RESPONSE

ROUTE UPDATE

TRANSITION TO DORMANT

NULL MESSAGE

NULL MESSAGETRAFFIC CHANNEL ASSIGNMENT

TRAFFIC CHANNEL COMPLETENEIGHBOR LIST


Backhaul and Related Considerations

Backhaul and Related Considerations


Rate Limitations from Backhaul

Wireless sites are commonly connected using T-1s or E-1s, depending on local availability

• In the case of T-1s, the raw rate is 1.544 megabits/second.– Accounting for overhead, this translates into a maximum

steady throughput of roughly 400 to 450 kb/s per sector on a 3-sector, 1-carrier EV-DO site.

– If one sector is busy while the other two are only lightly loaded, throughput of roughly 1 mb/s can be obtained on one sector

– However, early 1xEV-DO cards without support for multiple ARQ instances can only achieve about 400 kb/s throughput even without backhaul limitations

Solutions under study to relieve backhaul congestion include fiber-based ATM to the sites; multiple-T1s; sites linked by Cable Modems, and other methods


Speed of Individual Data Bursts

The average data rate received depends on:

• “dilution” of sector capacity by multiple users

• Reduction of speed due to poor RF channel conditions

The distribution of packet rates of one user show the effects of RF impairments only


1xEV-DO / 1xRTT Interoperability

1xEV-DO / 1xRTT Interoperability


1xEV-DO/1xRTT Interoperability

The CDMA2000 1xEV-DO Standard IS-856 makes no provision for any kind of handoff to or from any other technologyDriven by Operator interest, a “Hybrid” mode has been developed to provide some types of handoff functions to the best extent possibleHybrid Mode

• is a mobile only function – neither the EV nor 1xRTT network knows anything about it

• is a proprietary feature with vendor-specific implementation• has no standard-defined RF “triggers”; no “hooks”

In the 1xEV rev. A standard, some new features will be provided• the 1xEV control channel will be able to carry 1xRTT pages too• this and other changes may make the “hybrid” mode

unnecessary and obsolete


What Handoffs are Possible in Hybrid Mode?

All switching between systems occurs in Idle Mode• there are no “handoffs” in active traffic state in either mode

Sessions can be transferred from one system to the other, but NOT in active traffic state

• If there is a connection, it can be closed and then re-originated on the other system

• In some cases this can be accomplished automatically without the end-user’s awareness – in other cases, this is not possible


1xRTT / 1xEV-DO Hybrid Idle Mode

1xRTT/1xEV-DO Hybrid Mode• depends on being able to hear pages on both

systems – 1xRTT and 1xEV-DO• is possible because of slotted mode paging• 1xRTT and 1xEV-DO paging slots do not occur

simultaneously• mobile can monitor both

During 1xEV-DO traffic operation, the hybrid-aware mobile can still keep monitoring 1xRTT paging channelDuring 1xRTT traffic operation, the hybrid-aware mobile is unable to break away; 1xRTT traffic operation is continuous

• no opportunity to see 1xEV-DO signalThis hybrid Idle mode capability is the foundation for all 1xRTT/1xEV mode transfers

• the network does not trigger any transfers

1xR

TT

Act

ive

1xR

TT

Idle

1xEV

-DO

Idle

1xEV

-DO

A

ctiv

e

IdleMode

IdleMode

HybridMode


Hybrid Dual-Mode Idle Operation1xRTT / 1xEV-DO Paging Interoperability

A dual-mode 1xRTT/1xEV-DO mobile using slotted-mode paging can effectively watch the paging channels of both 1xRTT and 1xEV-DO at the same timeHow is it possible for the mobile to monitor both at the same time?

• The paging timeslots of the two technologies are staggeredThree of the 16 timeslots in 1xRTT conflict with the control channel slots of 1xEV-DO

• However, conflicts can be avoided by page repetition, a standardfeature in systems of both technologies

16-frame Control Channel Cycle16 slots of 26-2/3 ms = 426-2/3 ms

1xRTT Minimum Slot Cycle Index: 16 slots of 80 ms each = 48 26-2./3 ms frames1xRTT Minimum Slot Cycle Index: 16 slots of 80 ms each = 48 26-2./3 ms frames

16-frame Control Channel Cycle16 slots of 26-2/3 ms = 426-2/3 ms

LONGEST POSSIBLEPACKET

DRC 16 Subpackets


1xR

TT

Act

ive

1xR

TT

Idle

1xEV

-DO

Idle

1xEV

-DO

A

ctiv

eInitial System Acquisition by Hybrid Mobile

IdleMode

Acquire1xRTTSystem

driven byPRL

Registerwith

1xRTTNetwork

Acquire1xEV-DOSystem

driven byPRL

Classical 1xRTTIdle Mode

no, can’t see EV

VoicePage!

1xRTTVoiceCall

IdleMode

Release

when 1xEV-DO is NOT Available

After entering this state, the mobile will not search for

1xEV service again


1xR

TT

Act

ive

1xR

TT

Idle

1xEV

-DO

Idle

1xEV

-DO

A

ctiv

eInitial System Acquisition by Hybrid Mobile

IdleMode

Acquire1xRTTSystem

driven byPRL

Registerwith

1xRTTNetwork

Acquire1xEV-DOSystem

driven byPRL

Set Up orRe-establish

1xEVDOData

Session

yes, found EV

IdleMode

IdleMode

HybridMode

1xEVTraffic

AT DataReady!

AN DataPage!

DataConnectionClosed

VoicePage!

1xEVTraffic

1xRTTVoiceCall

IdleMode

HybridMode

IdleMode

IdleMode

HybridMode

Release

when 1xEV-DO is Available

interruptedduring1xRTT

voice call

Triggers:

132 tech intro cd ma

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