cdma forward channel
TRANSCRIPT
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CDMA TECHNOLOGY
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SECTION 2:
CDMA Forward Channels
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Objectives
To review types and methods of generation of
Pilot Channel
Paging Channel
Sync Channel
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Pilot Channel Generation
n The Walsh function zero spreading sequence is applied to the Pilot
n The use of short PN sequence offsets allows for up to 512 distinctPilots per CDMA channel
n The PN offset indexvalue (0-511 inclusive) for a given pilot PNsequence is multiplied by 64 to determine the actual offset
Example: 15 (offset index) x 64 = 960 PN chips
Result: The start of the pilot PN sequence will be delayed960 chips x 813.8 nanoseconds per chip = 781.25 s
n The quadrature spreading and baseband filtering (not shown),which are performed as with all the other forward and reversecode channels, will be discussed later
Pilot
Channel
(All 0s)
1.2288
Mcps
I PN
Q PN
Walsh
Function 0
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Walsh Codes Generation
00 0
0 1
0 0 0 0
0 1 0 1
0 0 1 1
0 1 1 0
W1
= W2
= W4
=
11 1
1 0
1 1 1 1
1 0 1 0
1 1 0 0
1 0 0 1
W1
= W2
= W4
=
W2 n
=W
nW
n
WnW
n
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Properties of the Walsh Codes
n When a Walsh code is XORed chip by chip withitself, the result is all 0s (100% correlation)
n When a Walsh code is XORed chip by chip with itslogical negation, the result is all 1s (100%
correlation)n When a Walsh code is XORed chip by chip with
any other code or its logical negation, the result ishalf 0s and half 1s (0% correlation)
0 0 0 00 1 0 1
0 0 1 1
0 1 1 0
0 0 0 0
0 1 0 1
0 1 0 1
0 1 0 1
0 1 0 1
0 0 0 0
0 0 1 1
0 1 0 1
0 1 1 0
0 1 1 0
0 1 0 1
0 0 1 1
1 1 1 1
0 1 0 1
1 0 1 0
1 0 1 0
0 1 0 1
1 1 1 1
1 1 0 0
0 1 0 1
1 0 0 1
1 0 0 1
0 1 0 1
1 1 0 0
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Orthogonality (Bit Strings)
a = (0, 1, 1, 0) b = (0, 1, 0, 1) -b = (1, 0, 1, 0)
+1
-1
+1
-1
+1
-1a = (+1, -1, -1, +1) b = (+1, -1, +1, -1) -b = (-1, +1, -1, +1)
a a =(+1)(+1) + (-1)(-1) + (-1)(-1) + (+1)(+1) = 1 + 1 + 1 + 1 = 4
a b =(+1)(+1) + (-1)(-1) + (-1)(+1) + (+1)(-1) = 1 + 1 - 1 - 1 = 0
b (-b) =(+1)(-1) + (-1)(+1) + (+1)(-1) + (-1)(+1) = -1 - 1 - 1 - 1 = -4
a XOR a = (0, 0, 0, 0) = 100% match
a XOR b = (0, 0, 1, 1) = 50% match & 50% no-match
b XOR -b = (1, 1, 1, 1) = 100% no-match
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Walsh Codes: Spreading a Signal
n Select a Walsh code
n
If the bit is 0, send the Walsh coden If the bit is 1, send the logical negation of the Walsh code
0 0 0 0
0 1 0 1
0 0 1 10 1 1 0
Selected Walsh code: 0 1 0 1 (used to represent code symbols 0)
Negated Walsh code: 1 0 1 0(used to represent code symbols 1)
Original sequence:
Spread sequence:
1 0 0 1 1 0
1 0 1 0 0 1 0 1 0 1 0 1 1 0 1 0 1 0 1 0 0 1 0 1
N = 4
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n XOR the received sequence with the sameWalsh code used for spreading it
n Perfect synchronization is a must
n
If a Walsh code produces N 0s, theoriginal bit was a 0
n If a Walsh code produces N 1s, theoriginal bit was a 1
0 0 0 0
0 1 0 1
0 0 1 1
0 1 1 0
(Original sequence):
Received sequence:
1 0 0 1 1 0
1 0 1 0 0 1 0 1 0 1 0 1 1 0 1 0 1 0 1 0 0 1 0 1
0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1Walsh code:
XOR: 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0
1 0 0 1 1 0
N = 4
Walsh Codes: De-spreading a Signal
(Using the Right Code)
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Walsh Codes: De-spreading a Signal
(Using the Wrong Code)
n If the received sequencel is XORed with aWalsh code other than the one used forspreading it, the result is neither groups of all0s or groups of all 1s, but groups containing
half the number of 0s and half the number of1s pseudorandomly distributed
n This indicates that nothing was coded usingthis Walsh code
0 0 0 0
0 1 0 1
0 0 1 1
0 1 1 0
(Original sequence):
Received sequence:
1 0 0 1 1 0
1 0 1 0 0 1 0 1 0 1 0 1 1 0 1 0 1 0 1 0 0 1 0 1
0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0Walsh code:
XOR: 1 1 0 0 0 0 1 1 0 0 1 1 1 1 0 0 1 1 0 0 0 0 1 1
? ? ? ? ? ?
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4-Bit Pseudo Noise (PN) Code Generator
p1
p2
p3
p4
p4
p5
p2
p3
p2
p3
p4
p5=p1 +p4
p4
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PN Sequence Generation
The PN sequences are deterministic and periodic.
The length of the generated string is 2n-1, where nis the number of elements in the register
The number of zeroes in the sequence is equal tothe number of ones minus 1
The beginning of the sequence is the 1 that followsn-1 zeroes; the final 0 of the sequence correspondsto the state of the register when all its elementsexcept the last one contain a zero
XORPN sequence 1 001
0 011
0 110
1 1011 010
0 101
1 011
0 111
1 111
1 110
10 0 0
0 010
0 100
1 100
1 000
0 100
X4+ X + 1Characteristic Polynomial
X4X0 X1 X2 X3
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PN Sequence Generation
using a Linear Feedback Register
1 000
0 001
0 010
1 100
1 001
0 011
1 110
0 101
1 010
1 101
10 1 1
0 110
0 100
1 011
1 111
0 100
i(n) = i(n-4) i(n-3)
XORPN sequenceh4 h3 h2 h1 h0
n-0 n-1 n-2 n-3 n-4
Linear Recursion
X4+ X + 1
XORPN sequence
X4X0 X1 X2 X3
Characteristic Polynomial
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Randomness of the Generated String
n The relative frequency ofzero and one is 1/2
n For zeroes and ones, half
the runs are of length 1;one quarter of the runs areof length 2; one eighth ofthe runs are of length 3;and so on
if a zero
is inserted:
1 0 0 1 1 0 1 0 1 1 1 1 0 0 02n-1
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 02n
543211245 3
Number of contiguous 0s Number of contiguous 1s
Number of
occurrences
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Correlation, Auto-correlation, and Cross-correlation
n In general, the correlationbetween two same-length bit strings is defined asthe degree of similarity between them
n When the correlation is determined between two copies of the same string, it iscalled auto-correlation
n When the correlation is determined between any two same-length strings , it iscalled cross-correlation
n A PN string (and, as a matter of fact, any bit string), when correlated (XORedchip by chip) with an unshifted copy of itself , shows 100% correlation (the resultis all 0s); and when correlated (XORed chip by chip) with an unshifted copy ofits logical negation, it shows -100% correlation (the result is all 1s)
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 0
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0XOR:
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 0
0 1 1 0 0 1 0 1 0 0 0 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1XOR:
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No Correlation
n A PN string, when compared to an identical shiftedcopy of itself, showsno or very little correlation. That is, when XORed with a shifted copy ofitself (or with the logical negation of a shifted copy of itself) the result isabout half 0s and half 1s
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 00 1 1 0 1 0 1 1 1 1 0 0 0 0 1 0
1 1 1 1 0 0 0 1 0 0 1 1 0 0 1 0XOR:
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 0
0 1 0 0 1 1 0 1 0 1 1 1 1 0 0 0
1 1 0 1 0 1 1 1 1 0 0 0 1 0 0 0XOR:
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0 0
1 0 0 1 0 1 0 0 0 0 1 1 1 1 0 1
0 0 0 0 1 1 1 0 1 1 0 0 1 1 0 1XOR:
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CDMA Short and Long PN Codes
CDMA uses three PN code sequences: two short and one long
n Thetwo short PN codes (called I and Q) are used for quadratuspreading to differentiate between CDMA partitions (sectors/cells)the forward direction
n The two short codes are generated by 15-bit PN code generators.The generated strings are 215-1 bits long plus one zero insertedfollowing the longest string of generated zeroes (32,768); and theicycle period is 26.666... milliseconds (or 75 times every 2 seconds
n Thelong PN code is used for spreading and data scrambling/randomization, and to differentiate among mobile stations in thereverse direction.
n The long code is generated by a 42-bit PN code generator. Thegenerated string is 242-1 with no zero inserted (about 4.4 trillion) bitlong; and its cycle period is approximately 41 days, 10 hours, 12minutes and 19.4 seconds.
n The three CDMA PN codes are synchronized to the beginning ofsystem time (January 6, 1980 at 00:00:00 hours)
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Sector / Cell Identification
11010010010110011010011001011011010011001011001100110011010011001011101000011001100101101001110101011000111010100010100110001010011000000000000000
10011001011011011100000010110011011101011001000011101011001010110111010101011000111010110011001011000001001110000100110011001110101000000000000000
0 1 2 511
I
Q
064 chips
0 800 1600 2400 3200 4000 4800 5600 6400 7200 8000feet
chips 0 1 2 3 4 5 6 7 8 9 10
50400 51200
63 64
5200 52800
65 66
miles 0 1 10
67
66
6564
6362
6160 59 58 57
4 3 2
2
3
1
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Pilot Channel Acquisition
n The mobile station starts generating the I and Q PN short sequencesby itself and correlating them with the received composite signal atevery possible offset
In less that 15 seconds (typically 2 to 4 seconds) all possibilities (32,768)are checked
The mobile station remembers the offsets for which it gets the bestcorrelation (where the E b/N0is the best
n The mobile station locks on the best pilot (at the offset that results inthe best Eb/N0), and identifies the pattern defining the start of theshort sequences (a 1 that follows fifteen consecutive 0s)
n Now the mobile station is ready to start de-correlating with Walshcode 32 to extract the Sync Channel (next section)
00...01 00...01 00...01 00...01 00...01 00...0100...01
PILOT CHANNEL
(Walsh Code 0)
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Frames and Messages
n Logical unit of transmission
n Fixed length
no need for length info
n Each frame includes one ormore overhead bits in addition
to the payload of informationbits
these overhead bits definethe structure of the frame
n Logical unit of information
n Variablelength
must include length info
n A message is broken intosmall pieces that can fit in the
payload portion of successiveframes
one frame overhead bit couldbe used to identify the initialsegment of a message
1 0 0 0 0 000
M E S S A G E
FRAME
FRAME MESSAGE
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Sync Channel
n Used to provide essential systemparameters
n Used during system acquisition stage
n The bit rate is 1200 bps
n
The Sync channel has a frameduration of 26 2/3ms
this frame duration matches theperiod of repetition of the PN ShortSequences
this simplifies the acquisition of theSync Channel once the Pilot Channelhas been acquired
n
The Mobile Station re-synchronizesat the end of every call
(Acquired Pilot)
Sync Channel
The Pilotchannel carries no data, therefore it has no frames.
The Syncchannel uses 26 2/3ms frames.
All other forward and reverse code channels use 20 ms frames.
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Sync Channel Generation
n There are32 bits (1200 bps x 0.02666... second) in one Sync Channel frame
n The Rate 1/2 convolutional encoder doubles the bit rate, and the resulting 0s and1s are now called code symbols
there are 64 code symbols in a Sync Channel frame
n The repetition process doubles the rate again, and each repetition of a codesymbol is now called a modulation symbol
there are 128 modulation symbols in a Sync Channel frame
n Four copies of Walsh code #32 are used to spread each modulation symbol,resulting in a x256 rate increase; the resulting 0s and 1s are now called chips
there are 32,768 chips in a Sync Channel frame (1024 chips per original bit)
1200 bps
Walsh Function 32
1.2288 Mcps
IPN
QPN
ConvolutionalEncoderand
Repetition
Block
Interleaver
R=1/2
Modulation
Symbols
4800 sps 4800 sps
Bits Chips
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Sync Channel Modulation Parameters
* In the CDMA Forward Code Channels, each repetition of a
code symbol is called a modulation symbol
Data Rate
PN Chip Rate
Code Rate
Code Repetition
Modulation Symbol Rate
PN Chips / Modulation Symbol
PN Chips / Bit
Bits Per Second
Mega Chips Per Second
Bits Per Code Symbol
Modulation Symbols* Per Code Symbol
Symbols Per Second
PN Chips / Modulation Symbol
PN Chips / Bit
1200
1.2288
1 / 2
2
4800
256
1024
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Convolutional Encoder
IN
OUT
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Rate 1/2, K=9 Convolutional Encoding
n Symbols generated as the information bits transit through the encoder, arerelated to all the bits currently in the register
n Each information bit contributes to multiple generated symbols
n This pattern of inter-relationships helps detect and correct errorsn The length of shift register plus 1 is called the constraint length of the
convolutional encoder (K=9 in this case)
The longer the register, the better this scheme can correct bursty errors
Reduces power required to achieve same accuracy as without coding
n Here, two symbols are generated for every bit input (Rate 1/2)
Code Symbol
Output
1 2 3 4 5 6 7 8
g0
g1
c0
c1
Data
Bit
Input
(Data Bit is
discarded)
Code Symbol
Output
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Step-by-Step Example (Rate 1/2, k=4)
b1b2b3b4b5b6
b2b3b4b5b6 b1
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Step-by-Step Example (Rate 1/2, k=4)cont.
b1b2b3b4b5b6 b2b3b4b5b6 b1
b1
b2
b3
b4
b5
b6
C0,4= b4+b3+ b1
C1,4
= b4+
b
2+ b
1
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Step-by-Step Example (step 1)
??b1b2b3 ?
???b1b2b3
???b1b2b3
C0,1
C1,1
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Step-by-Step Example (step 2)
?b1b2b3 ?
??b1b2b3
??b1b2b3
C0,2C0,1
C1,2 C1,1
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Step-by-Step Example (step 3)
b1b2b3 ?
?b1b2b3
?b1
b2
b3
C0,3C0,2C0,1
C1,3C1,2C1,1
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An Even Simpler Convolutional Encode
+
+
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State Diagram
+
+
110
0 + 1 =1
0 + 1 + 1 =0
+
+
110
0
0 1
1
+
+
10 1
11
01
00
10
1
0
1
1
0
1
0
10
01 01
10
00
00
11
0
11
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State Diagram as a Binary Tree
00
01
10
11
00
01
10
11
11
01
00
10
1
0
1
1
0
1
0
10
01 01
10
00
00
11
0
11
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
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Trellis Diagram
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
00
01
10
11
00
01
10
11
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Code Words
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
11
1
1
1
0
0
0
0
00
01
10
00
10
01
10
1
00
01
10
11
00
01
10
11
1 0 1 0 1 1 0 0
11-10-00-10-00-01-01-11
11
1
0
10
00
1
1
0
10
00
1
001
01
0
10
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Hamming and Free Distance
number of possible received
16-bit sequences:
216= 65,536
00 0000 00
00 0001 00
00 001 0 00
00 001 1 00
101 011 00
1 1 1 1 01 00
1 1 1 1 1 0 00
1 1 1 1 1 1 00
11-10-00-10-00-01-01-11
26= 64
valid code words: 26= 64
10-11-00-1 1 -00-0 0-01-11
one-to-one
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Viterbi Decoder
0
1
1 1
1
1
1
0
0
0
0
0
0
1
1st
node
2st
node
3rd
node
4th
node
n Integrated circuit that implements the maximumlikelihood algorithm devised by Andrew Viterbi in
1967
n Operates based on determining the correlation
between the sections of the received signal andeach one of the valid codes
n The Viterbi decoder uses a search tree tocontinuously calculate the Hamming distance
between the received and valid codes. If anerror path is detected, the decoder goes back tothe previous node and tries the alternative path
n The code that generates the maximal amount ofenergy has the greater probability of being theone that was transmitted
Sync Channel Block Interleaver
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Sync Channel Block Interleaver
(Input Matrix)
1 9 17 25 33 41 49 57
1 9 17 25 33 41 49 57
2 10 18 26 34 42 50 58
2 10 18 26 34 42 50 58
3 11 19 27 35 43 51 59
3 11 19 27 35 43 51 59
4 12 20 28 36 44 52 60
4 12 20 28 36 44 52 60
5 13 21 29 37 45 53 61
5 13 21 29 37 45 53 61
6 14 22 30 38 46 54 62
6 14 22 30 38 46 54 62
7 15 23 31 39 47 55 63
7 15 23 31 39 47 55 63
8 16 24 32 40 48 56 64
8 16 24 32 40 48 56 64
Sync Channel Block Interleaver
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Sync Channel Block Interleaver
(Output Matrix)
1 3 2 4 1 3 2 4
33 35 34 36 33 35 34 36
17 19 18 20 17 19 18 20
49 51 50 52 49 51 50 52
9 11 10 12 9 11 10 12
41 43 42 44 41 43 42 44
25 27 26 28 25 27 26 28
57 59 58 60 57 59 58 60
5 7 6 8 5 7 6 8
37 39 38 40 37 39 38 40
21 23 22 24 21 23 22 24
53 55 54 56 53 55 54 56
13 15 14 16 13 15 14 16
45 47 46 48 45 47 46 48
29 31 30 32 29 31 30 32
61 63 62 64 61 63 62 64
assume that a burst of noise affects these symbols
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Sync Channel Block Interleaver
Restored1 9 17 25 33 41 49 57
1 9 17 25 33 41 49 57
2 10 18 26 34 42 50 58
2 10 18 26 34 42 50 58
3 11 19 27 35 43 51 59
3 11 19 27 35 43 51 59
4 12 20 28 36 44 52 60
4 12 20 28 36 44 52 60
5 13 21 29 37 45 53 61
5 13 21 29 37 45 53 61
6 14 22 30 38 46 54 62
6 14 22 30 38 46 54 62
7 15 23 31 39 47 55 63
7 15 23 31 39 47 55 63
8 16 24 32 40 48 56 64
8 16 24 32 40 48 56 64
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Sync Channel Structure
000001 0
26.67 m s
32 b its
31 bits
Sync Chann el Mes sage Caps ule (93 x Nsbits)
Sync Channel Messag e (8 x MSG_LENGTH)
8 bits 30 bits
MSG_LENGTH
2-1146 bits
as required
Sync Channel Superf rame Sync Channel Superf rame
Sy nc Channel Frame Body
Sync Channel Fr am e
SOM
Message Body CRC
Sync Channel Message Padd ing
80 ms, 96 bits
1200 b ps
Ns = Numbe r o f S y nc
Chann e l Sup er f r ames
needed f o r m es sag e
t r ansm i s s i on
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Sync Channel Acquisition
00...01 00...01 00...01 00...01 00...01 00...0100...01
0 0 1 0 0 0
LEN
PILOT CHANNEL
(Walsh Code 0)
SYNC CHANNEL
(Walsh Code 32)
CRCSync Channel Message Body
8 bits 30 bits170 bits
208 bits
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Sync Channel Message Body Format
n When the Base Stationsends a Sync ChannelMessage, it uses thefixed-length messageformat illustrated here
MSG_TYPE (00000001)
P_REV
MIN_PREV
SID
NID
PILOT_PN
LC_STATE
SYS_TIME
LP_SEC
LTM_OFF
DAYLT
PRAT
CDMA_FREQ
8
8
8
15
16
9
42
36
8
6
1
2
11
SYNC
FieldLength(bits)
Total : 170
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Mobile Station Timing
Synchronization
26.666... ms
80 ms
superframe
320 ms
Pilot PNSequence
Offset
SyncChannel
System Time
Pilot PNSequence
Offset
Time Specified in
Sync Channel
Message
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Paging Channels
n Up to seven paging channels can be supported on a single CDMAfrequency assignment
n Channel 1 (Walsh function 1) is the Primary Paging Channel
n Additional Paging Channels use Walsh functions 2 through 7
n Unused paging channels can be used as Forward Traffic Channelsn Two rates are supported: 9600 and 4800 bps (PRAT parameter in
the Sync Channel Message)
n A s ingle 9600 bps Paging Channel can support about 180 pages
per second
Paging Channel
Used by the base station to
transmit system overhead information
and mobile station-specific messages.
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Paging Channel Generation
n There are 192 [96] bits (9600 [4800] bps x 0.020 second) in one PagingChannel frame
n The Rate 1/2 convolutional encoder doubles the bit rate, resulting 384 [192]code symbols in a Paging Channel frame
n If the 4800 bps rate is used, the repetition process doubles the rate again, so
that, at either rate, 384 modulation symbols per Paging Channel frame resultn 384 modulation symbols per frame times 50 frames per second = 19.2 Ksps
n One copy of Walsh code #1 (or #2, ... or #7) is used to spread each modulationsymbol. This results in a x64 rate increase to 1.2288 Mcps
that is, 24,576 chips per Paging Channel frame, or 128 [256] chips peroriginal bit at 9600 [4800] bps
9600 bps
4800 bps
Walsh
function
1.2288Mcps
Q PN
1.2288
Mcps
19.2
Ksps
19.2
KspsPaging ChannelAddress Mask
R = 1/2
Decimator
Convolutional
Encoder &
Repetition
I PN
Block
Interleaving
Scrambling
Long PN Code
Generator
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Paging Channel Modulation Parameters
Data Rate Bits Per Second48009600
PN Chip Rate Mega Chips Per Second1.22881.2288
Code Rate Bits Per Code Symbol1/21/2
Code Repetition Modulation symbols * per code symbol21
Modulation Symbol Rate Code Symbols Per Second1920019200
PN Chips / Modulation Symbol PN Chips Per Modulation Symbol6464
PN Chips / Bit PN Chips Per Bit256128
* Each repetition of a code symbol is a modulation symbol
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n The 384 modulation symbols in a frame are input into a 24 by 16block interleaver array (read down by columns, from left to right)
n The array represents a 20 ms interval worth of information
1 25 49 73 97 121 145 169 1 93 217 241 2 65 289 313 3 37 361
2 26 50 74 98 122 146 170 1 94 218 242 2 66 290 314 3 38 362
3 27 51 75 99 123 147 171 1 95 219 243 2 67 291 315 3 39 363
4 28 52 76 100 1 24 148 172 1 96 220 244 2 68 292 316 3 40 364
5 29 53 77 101 1 25 149 173 1 97 221 245 2 69 293 317 3 41 365
6 30 54 78 102 1 26 150 174 1 98 222 246 2 70 294 318 3 42 366
7 31 55 79 103 1 27 151 175 1 99 223 247 2 71 295 319 3 43 367
8 32 56 80 104 1 28 152 176 2 00 224 248 2 72 296 320 3 44 368
9 33 57 81 105 1 29 153 177 2 01 225 249 2 73 297 321 3 45 369
10 3 4 58 82 10 6 130 154 17 8 202 226 25 0 274 29 8 32 2 346 37 0
11 3 5 59 83 10 7 131 155 17 9 203 227 25 1 275 29 9 32 3 347 37 1
12 3 6 60 84 10 8 132 156 18 0 204 228 25 2 276 30 0 32 4 348 37 2
13 3 7 61 85 10 9 133 157 18 1 205 229 25 3 277 30 1 32 5 349 37 3
14 3 8 62 86 11 0 134 158 18 2 206 230 25 4 278 30 2 32 6 350 37 4
15 3 9 63 87 11 1 135 159 18 3 207 231 25 5 279 30 3 32 7 351 37 5
16 4 0 64 88 11 2 136 160 18 4 208 232 25 6 280 30 4 32 8 352 37 6
17 4 1 65 89 11 3 137 161 18 5 209 233 25 7 281 30 5 32 9 353 37 7
18 4 2 66 90 11 4 138 162 18 6 210 234 25 8 282 30 6 33 0 354 37 8
19 4 3 67 91 11 5 139 163 18 7 211 235 25 9 283 30 7 33 1 355 37 9
20 4 4 68 92 11 6 140 164 18 8 212 236 26 0 284 30 8 33 2 356 38 0
21 4 5 69 93 11 7 141 165 18 9 213 237 26 1 285 30 9 33 3 357 38 1
22 4 6 70 94 11 8 142 166 19 0 214 238 26 2 286 31 0 33 4 358 38 2
23 4 7 71 95 11 9 143 167 19 1 215 239 26 3 287 31 1 33 5 359 38 3
24 4 8 72 96 12 0 144 168 19 2 216 240 26 4 288 31 2 33 6 360 38 4
16 Columns
24 rows
Paging Channel - 9600 bps Block Interleaver
(Input Array)
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9600 bps Block Interleaver (Output Array)
1 9 5 13 3 11 7 15 2 10 6 14 4 12 8 16
65 73 69 77 67 75 71 79 66 74 70 78 68 76 72 80
129 137 133 141 131 139 135 143 130 138 134 142 132 140 136 144
193 201 197 205 195 203 199 207 194 202 198 206 196 204 200 208
257 265 261 269 259 267 263 271 258 266 262 270 260 268 264 272
321 329 325 333 323 331 327 335 322 330 326 334 324 332 328 336
33 41 37 45 35 43 39 47 34 42 38 46 36 44 40 48
97 105 101 109 99 107 103 111 98 106 102 110 100 108 104 112
161 169 165 173 163 171 167 175 162 170 166 174 164 172 168 176
225 233 229 237 227 235 231 239 226 234 230 238 228 236 232 240
289 297 293 301 291 299 295 303 290 298 294 302 292 300 296 304
353 361 357 365 355 363 359 367 354 362 358 366 356 364 360 368
17 25 21 29 19 27 23 31 18 26 22 30 20 28 24 32
81 89 85 93 83 91 87 95 82 90 86 94 84 92 88 96
145 153 149 157 147 155 151 159 146 154 150 158 148 156 152 160
209 217 213 221 211 219 215 223 210 218 214 222 212 220 216 224
273 281 277 285 275 283 279 287 274 282 278 286 276 284 280 288
337 345 341 349 339 347 343 351 338 346 342 350 340 348 344 352
49 57 53 61 51 59 55 63 50 58 54 62 52 60 56 64
113 121 117 125 115 123 119 127 114 122 118 126 116 124 120 128
177 185 181 189 179 187 183 191 178 186 182 190 180 188 184 192
241 249 245 253 243 251 247 255 242 250 246 254 244 252 248 256
305 313 309 317 307 315 311 319 306 314 310 318 308 316 312 320
369 377 373 381 371 379 375 383 370 378 374 382 372 380 376 384
Assume that a
burs t of no ise
damages al l
these bi ts
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9600 bps De-interleaving
1 25 4 9 7 3 97 12 1 1 45 1 69 19 3 2 17 2 41 26 5 2 89 3 13 33 7 3 612 26 5 0 7 4 98 12 2 1 46 1 70 19 4 2 18 2 42 26 6 2 90 3 14 33 8 3 62
3 27 5 1 7 5 99 12 3 1 47 1 71 19 5 2 19 2 43 26 7 2 91 3 15 33 9 3 63
4 28 5 2 7 6 1 00 12 4 1 48 1 72 19 6 2 20 2 44 26 8 2 92 3 16 34 0 3 64
5 29 5 3 7 7 1 01 12 5 1 49 1 73 19 7 2 21 2 45 26 9 2 93 3 17 34 1 3 65
6 30 5 4 7 8 1 02 12 6 1 50 1 74 19 8 2 22 2 46 27 0 2 94 3 18 34 2 3 66
7 31 5 5 7 9 1 03 12 7 1 51 1 75 19 9 2 23 2 47 27 1 2 95 3 19 34 3 3 67
8 32 5 6 8 0 1 04 12 8 1 52 1 76 20 0 2 24 2 48 27 2 2 96 3 20 34 4 3 68
9 33 5 7 8 1 1 05 12 9 1 53 1 77 20 1 2 25 2 49 27 3 2 97 3 21 34 5 3 69
10 34 5 8 8 2 1 06 13 0 1 54 1 78 20 2 2 26 2 50 27 4 2 98 3 22 34 6 3 70
11 35 5 9 8 3 1 07 13 1 1 55 1 79 20 3 2 27 2 51 27 5 2 99 3 23 34 7 3 71
12 36 6 0 8 4 1 08 13 2 1 56 1 80 20 4 2 28 2 52 27 6 3 00 3 24 34 8 3 72
13 37 6 1 8 5 1 09 13 3 1 57 1 81 20 5 2 29 2 53 27 7 3 01 3 25 34 9 3 73
14 38 6 2 8 6 1 10 13 4 1 58 1 82 20 6 2 30 2 54 27 8 3 02 3 26 35 0 3 74
15 39 6 3 8 7 1 11 13 5 1 59 1 83 20 7 2 31 2 55 27 9 3 03 3 27 35 1 3 75
16 40 6 4 8 8 1 12 13 6 1 60 1 84 20 8 2 32 2 56 28 0 3 04 3 28 35 2 3 76
17 41 6 5 8 9 1 13 13 7 1 61 1 85 20 9 2 33 2 57 28 1 3 05 3 29 35 3 3 77
18 42 6 6 9 0 1 14 13 8 1 62 1 86 21 0 2 34 2 58 28 2 3 06 3 30 35 4 3 78
19 43 6 7 9 1 1 15 13 9 1 63 1 87 21 1 2 35 2 59 28 3 3 07 3 31 35 5 3 79
20 44 6 8 9 2 1 16 14 0 1 64 1 88 21 2 2 36 2 60 28 4 3 08 3 32 35 6 3 80
21 45 6 9 9 3 1 17 14 1 1 65 1 89 21 3 2 37 2 61 28 5 3 09 3 33 35 7 3 81
22 46 7 0 9 4 1 18 14 2 1 66 1 90 21 4 2 38 2 62 28 6 3 10 3 34 35 8 3 82
23 47 7 1 9 5 1 19 14 3 1 67 1 91 21 5 2 39 2 63 28 7 3 11 3 35 35 9 3 83
24 48 7 2 9 6 1 20 14 4 1 68 1 92 21 6 2 40 2 64 28 8 3 12 3 36 36 0 3 84
16Columns
24rows
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Data Scrambling (Data Randomization
Binary
Stream
10%: 0
90%: 1
5%: XOR with 0
5%: XOR with 1
45%: XOR with 0
45%: XOR with 1
0
1
1
0
50%: 1
50%: 0
XOR with 0
XOR with 1
XOR with 0
XOR with 1
0
0
1
1
10%: 0
90%: 1
Random
sequence
of 0s and 1s
The same
random
sequence
of 0s and 1s
10%: 0
90%: 1
Exactly the same random sequence of 0s and 1s must
be used at both ends. Perfect synchronization is required.
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Masks
modulo 2 addition (same as XOR)
mask
XOROriginal PN
sequence
New PN
sequence
AND AND AND AND
1 001
0 011
0 110
1 101
1 010
0 101
1 011
0 111
1 111
1 110
10 0 0
0 010
0 100
1 1001 000
0 100
M k (E l 1)
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Masks (Example 1)
Notice that not every bit in the mask needs to be ANDed with the corresponding register bit,
but not ANDing a particular mask bit with the corresponding register bit has the same effectas making this bit 0 and ANDing it anyway!
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0
0 1 1 1 1 0 0 0 1 0 0 1 1 0 1
without mask:
with mask 1101:
10 0 0
11 0 1
10 0 0 1
0 010
11 0 1
00 0 0 0
0 100
11 0 1
00 0 1 1
1 001
11 0 1
11 0 0 0
0 011
11 0 1
10 0 0 1
0 110
11 0 1
00 0 1 1
1 101
11 0 1
11 0 1 1
1 010
11 0 1
01 0 0 1
0 101
11 0 1
10 0 1 0
1 011
11 0 1
11 0 0 0
0 111
11 0 1
10 0 1 0
1 111
11 0 1
11 0 1 1
1 110
11 0 1
01 0 1 0
1 100
11 0 1
01 0 1 0
1 000
11 0 1
01 0 0 1
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Masks (Example 2)
1 0 0 1 1 0 1 0 1 1 1 1 0 0 0
0 1 0 0 1 1 0 1 0 1 1 1 1 0 0
without mask:
with mask 1100:
10 0 0
11 0 0
10 0 0 1
0 010
11 0 0
00 0 0 0
0 100
11 0 0
00 0 0 0
1 001
11 0 0
11 0 0 0
0 011
11 0 0
10 0 0 1
0 110
11 0 0
00 0 0 0
1 101
11 0 0
11 0 0 0
1 010
11 0 0
01 0 0 1
0 10111 0 0
10 0 0 1
1 01111 0 0
11 0 0 0
0 11111 0 0
10 0 0 1
1 11111 0 0
11 0 0 0
1 11011 0 0
01 0 0 1
1 100
11 0 0
01 0 0 1
1 000
11 0 0
01 0 0 1
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Paging Channel Scrambling
A Paging Channel is scrambled by the long code,
offset by a mask constructed as follows:
Where:
PCN is the Paging Channel Number, and
PILOT_PN is the Pilot short PN code offset index
1100011001101 00000 PCN 000000000000 PILOT_PN
41 29 28 24 23 21 20 9 8 0
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Paging Channel Structure
R = 9600 or 4800 bps
(1) First new capsul e in slot, Synchronized Capsule
(2) Unsynchronized Capsules
(3) Synchronized Capsules
8 x MSG_LENGTHas required
SCI
8 bits 30 bits (see note
in text)
163.84 ms, 163.84 x R bits
2048 slots
8 Half Frames per Slot
(1) (2) (3)
10 ms
SCI : Synchronized Capsule Indicator
Maximum Paging Channel Slot Cycle
Slot Channel 0 Slot Channel n Slot Channel 2047
Half Frame Half Frame Half Frame Half Frame Half Frame
Half Frame Body Half Frame Body Half Frame Body Half Frame Body Half Frame Body 0 1 0 0 1 0
age Capsule Message Capsule Message Capsule Message
PaddingMessage Paging Channel Message Paging Channel Message Padding Pagi ng Ch
MSG_LENGTH Message Body CRC
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Paging Channel Determination
n CDMA Channel (1.25 MHz band) Determination
In a CDMA system with multiple CDMA channels, the mobilestation must first determine the CDMA channel to be used
For this, it will use a hash function with the mobile stationsIMSI and the number of CDMA Channels on which the basestation transmits Paging Channels as input
n Paging Channel Determination
Then the mobile station must select a Paging Channel among
those transmitted in that CDMA channelFor this, it will use a hash function with the mobile stations
IMSI and the number of Paging Channels on the selectedCDMA frequency
Paging Channel Modes
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Paging Channel Modes
n
Non-Slotted Mode Operation The mobile station continuously monitors the Paging Channel
Paging Channel messages can occupy any one of the 2048 slotin the maximum slot cycle
n Slotted Mode Operation
Provides scheduled transmission of messages for a specific
mobile station
Monitoring frequency can range from every 1.28 seconds to onevery 163.84 seconds
Support is optional and enabled by the mobile station
The mobile station can sleep or reduce power consumptionduring non-active states
n The mobile station must indicate the desired operating mode bymeans of the SLOTTED_MODE field in one certain messages.
n The mobile station is operating in slotted mode, it can alsospecify its preferred slot cycle index by means of theSLOT_CYCLE_INDEX field in the same message.
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Slot Cycles
7
6
5
4
3
2
1
0
SCI 163.84 s
T=2SCI
= Slot Cycle Index
T =Slot Cycle Length in 1.28 s units80 ms
1.28 s
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Paging Slot Determination
n To determine its assigned paging slots, the mobile station uses thehash function to select a number, PGSLOT, in the range 0 to 2047(spanning the maximum slot cycle which is 163.84 seconds)
DECORR= 6xHASH_KEY [0..11]
PGSLOT= int 2048 40503 HXORLXORDECORR mod 216( )( )( )
216( )
HASH_KEY
H
IMSI_S (34 bits)
0151631
L
33 11
HASH_KEY [0..11]
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where t is the system time in frames and SCI is the slot cycle index
nThe mobile stations assigned slots are given by:
7
6
5
4
SCI 163.84 s
PGSLOT
intt
4-PGSLOT mod 16 2
SCI
(int (t/4)-PGSLOT)mod(16 x T) = 0
Paging Slot Determination
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Slotted Mode Operation
n The figure shows an example for a slot cycle length of 1.28 seconds (16 slots) in
which, based on PGSLOT, the slot to be monitored was determined to be the 13th.
n The mobile station wakes up at slot #12 and re-acquires the system
n It monitors the slot for messages during slot #13n The next slot the mobile station must monitor is 16 slots later (slot #29)
n If a page message started in one slot does not fit, it continues in the following slot(each paging message must be completely contained in one or two slots)
n Eventually the mobile realizes that there are no more pages for its class (see GeneralPage Message structure discussed later) and goes back to sleep
System Time
Paging Channel Slots
2047 0 1 2 3 4 12 13 14 15 16 17
1.28seconds
Mobile Stationin Non-Active State
Assigned PagingChannel Slot
Re-acquisitionofCDMA System
Mobile Stationin Non-Active State
80 ms
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Paging Channel Overhead Messages
Mobile-Station-
Directed
Messages
Overhead
Messages
Access Parameters Message
System Parameters Message
CDMA Channel List Message
Extended System Parameters Message
Extended Neighbor List Message
Configuration
Parameter
Messages
Global Service Redirection Message
PagingMessages
ACC_CONFIG_SEQ
CONFIG_SEQ
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Paging Channel Mobile-Station-Directed Messages
Mobile-Station-
DirectedMessages
OverheadMessages
Paging
Messages Channel Assignment Message
SSD Update Message
Feature Notification Message
Service Redirection Message
General Page Message
Null Message
Data Burst Message
Order Message
Status Request Message
TMSI Assignment Message
Authentication Challenge Message
All Fwd & RevChannels
Except Pilotand Synch
Paging &Fwd Traffic
Paging only
Onlyselected fieldsof the System Parameters
Message are discussed next. All the other fields
in this message as well as some of the
remaining overhead messages are discussed
later where it is more appropriate.
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System Parameters Message (Paging Channels)
MSG_TYPE (00000001)
PILOT_PN
8
9
CONFIG_MSG_SEQ 6
SID 15
NID 16
REG_ZONE 12
TOTAL_ZONES 3
ZONE_TIMER 3
MULT_SIDS 1
MULT_NIDS 1
BASE_ID 16
BASE_CLASS 4
PAGE_CHAN 3
MAX_SLOT_CYCLE_INDEX 3
HOME_REG
FOR_SID_REG
1
1
FOR_NID_REG 1
POWER_UP_REG 1
POWER_DOWN_REG 1
PARAMETER_REG 1
REG_PRD 7
BASE_LAT 22
BASE_LONG 23
REG_DIST 11
SRCH_WIN_A 4
SRCH_WIN_N 4
SRCH_WIN_R 4
NGHBR_MAX_AGE 4
PWR_REP_THRESH
PWR_REP_FRAMES
5
4
PWR_THRESH_ENABLE 1
PWR_PERIOD_ENABLE 1
PWR_REP_DELAY 5
RESCAN 1
T_ADD 6
T_DROP 6
T_COMP 4
T_TDROP 4
EXT_SYS_PARAMETER 1
EXT_NGHBR_LIST 1
GLOBAL_REDIRECT 1
RESERVED (0s) 1
REGISTRATION
POWER CONTROL
HANDOFFS
(THRESHOLDS)
HANDOFFS
(PILOT SEARCH)
TRATION
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MSG_TYPEMessage type: 00000001
PILOT_PNPilot PN offset index for this base station.
CONFIG_MSG_SEQCurrent value of CONFIG_SEQ
SIDSystem identification
NIDNetwork identification
MULT_SIDS1 if the mobile station may store multiple entries of SID_NID_LIST containing
different SIDs; 0 otherwise.
MULT_NIDS1 if the mobile station may store multiple entries of SID_NID_LIST having the
same SID (with different NIDs); 0 otherwise.
BASE_IDThis base station identification number
BASE_CLASS0001 indicating that this is a Public PCS System
System Parameters Message (Paging Channels)cont.
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PAGE_CHANNumber of Paging Channels on this CDMA Channel in this base station (cannot be
000)
MAX_SLOT_CYCLE_INDEXMaximum value permitted for the Slot Cycle Index in this base
station
RESCAN1 if the mobile stations are to re-initialize and re-acquire the system upon receiving thismessage; 0 otherwise
EXT_SYS_PARAMETER1 if the base station sends the Extended System Parameters
Message on the Paging Channel; 0 otherwise
EXT_NGHBR_LIST1 if the base station sends the Extended Neighbor List Message on the
Paging Channel; 0 otherwise
GLOBAL_REDIRECT1 if the base station is sending the Global Service Redirection
Message on the Paging Channel; 0 otherwise
System Parameters Message (Paging Channels)cont.
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CDMA Channel List Message (Paging Channels)
A 25, 50, 75, 100, 125, 150, 175, 200, 225, 250, 275
D 325, 350, 375
B 425, 450, 475, 500, 525, 550, 575, 600, 625, 650, 675
E 725, 750, 775
F 825, 850, 875
C 925, 950, 975, 1000, 1025, 1050, 1075, 1100, 1025, 1150, 1175
Block Preferred Set Channel Numbers
MSG_TYPE (00000100) 8
PILOT_PN 9
CONFIG_MSG_SEQ 6
CDMA_FREQ 11
RESERVED (0s) 0 - 7 (as needed)
Field Length (bits)
One or more occurrences of the following:
One occurrence of the following:
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CDMA_FREQCDMA Channel frequency assignment. The base station includes one
occurrence of this field for each CDMA Channel that is supported by this base station.
Each occurrence of this field is set to the CDMA channel number for the corresponding
CDMA Channel assignment.
The order in which occurrences of this field are included gives the designations of thesupported CDMA Channels as CDMA Channel 1 through CDMA Channel N.
CDMA Channels in the preferred set of CDMA frequency assignments should occur
first.
RESERVEDThis field contains as many zeroes as needed in order to make the length
of the entire message an integer number of octets.
CDMA Channel List Message (Paging Channels)cont.
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Extended System Parameters Message (Paging Channels)
MSG_TYPE (00001101)
PILOT_PN
CONFIG_MSG_SEQ
RESERVED (0)
PREF_MSID_TYPE
MCC
IMSI_11_12
TMSI_ZONE_LEN
TMSI_ZONE
BCAST_INDEX
RESERVED (0000000)
8
9
6
1
3
10
7
4
8 x TMSI_ZONE_LEN
3
7
Field Length (bits)
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PREF_MSID_TYPEPreferred Access Channel Mobile Station Identifier Type. Defines the type of MSID that the
mobile station is to use on the Access Channel. Values are as follows:
000 IMSI
001 IMSI and ESN
010 TMSI (valid TMSI is assigned); IMSI (TMSI not assigned)
011 TMSI (valid TMSI is assigned); IMSI and ESN (TMSI not assigned)
ALL OTHER VALUES ARE RESERVED.
MSID:
MCCMobile Country Code.
MOBILE COUNTRY CODE: 1 to three digits identifying the country, as defined in CCITT Blue
Book, Volume II, Fascicle II.2, Recommendation E.212, November 1988.
IMSI_11_12Digits 11 and 12 of the IMSI.
DIGITS 11 AND 12 OF THE IMSI: Same as the Mobile Network Code (MNC).
TMSI_ZONE_LENNumber of octets in the TMSI_ZONE field.
TMSI_ZONENumber of this TMSI zone. (TMSI zone is an administrative zone that allows the TMSI to be
reused).
BCAST_INDEXBroadcast Slot Cycle Index. To enable periodic broadcast paging, the base station sets this field to
an unsigned 3-bit value (1-7) equal to the broadcast slot cycle index. To disable periodic broadcast paging, the base
station sets this field to 000.
Extended System Parameters Message (Paging Channels)cont.
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Extended Neighbor List Message (Paging Channels)
MSG _TYPE (00001110)
PILOT_PN
CONFIG_MSG_SEQ
PILOT_INC
NGHBR_CONFIG
NGHBR_PN
SEARCH_PRIORITY
FREQ_INCL
NGHBR_BAND
NGHBR_FREQ
RESERVED (0s)
8
9
6
4
3
9
2
1
0 or 5
0 or 11
0 - 7 (as needed)
Field Length (bits)
Zero or more occurrences of the following record:
One occurrence of the following field:
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PILOT_INCThe mobile station will search for the Remaining Set pilots as pilot PN sequence index values that aremultiples of the value (1-15) in this field.
NGHBR_CONFIGDescribes the configuration of the neighbor corresponding to this record relative to theconfiguration of this base station as follows:
000 Has the samenumber of frequencies with Paging Channels, and withthesamenumber of Paging Channels
FREQ_INCL = 0: frequency assignment is the same as in the currentcurrent base station
FREQ_INCL =1: frequency assignment is given by NGHBR_BANDand NGHBR_FREQ
001 Has the samenumber of frequencies with Paging Channels, but withadifferentnumber of Paging ChannelsFREQ_INCL = 0: frequency assignment is the same as in the current
current base station
FREQ_INCL =1: frequency assignment is given by NGHBR_BAND
and NGHBR_FREQ010 May have a differentnumber of frequencies with Paging Channels
FREQ_INCL = 0: neighbor has a Primary Paging Channel on the firstCDMA channel listed in the CDMA Channel List Message transmitted
by the current base stationFREQ_INCL =1: neighbor has a Primary Paging Channel in the
frequency assignment is given by NGHBR_BAND and NGHBR_FREQ
Extended Neighbor List Message (Paging Channels)cont.
Extended Neighbor List Message (Paging Channels)cont.
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011 This neighbors configuration is unknown
FREQ_INCL = 0: this CDMA frequency assignment has a Pilot ChannelFREQ_INCL = 1: the CDMA frequency assignment given by
NGHBR_BAND and NGHBR_FREQ has a Pilot Channel
ALL OTHER VALUES ARE RESERVED.
NGHBR_PNPilot PN sequence offset index for the neighbor (in units of 64 PN chips).
SEARCH_PRIORITYDefines the search priority for the Pilot Channel corresponding to NGHBR_PN as follows:
00 Low01 Medium10 High11 Very High
FREQ_INCLFrequency included indicator. This field is set to 1 if the NGHBR_FREQ field for this neighbor basestation is included in this record; and it is set to 0 if not.
NGHBR_BANDCDMA band class as follows:
0 800 MHz cellular1 1900 MHz PCS
NGHBR_FREQCDMA Channel number of the CDMA Channel containing the Paging Channel the mobile station is tosearch for.
RESERVEDEnough zero bits to make the length of the message an integer number of octets.
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Global Service Redirection Message, (Paging Channels)
MSG_TYPE (00010010)
PILOT_PN
CONFIG_MSG_SEQ
REDIRECT_ACCOLC
RETURN_IF_FAIL
RECORD_TYPE
RECORD_LEN
Type-specific fields
8
9
6
16
1
8
8
8 x RECORD_LEN
Field Length (bits)
One occurrence of the following record:
BAND_CLASS 5
EXPECTED_SID 15
EXPECTED_NID 16
RESERVED 4
NUM_CHANS 4
CDMA_CHAN 11
RESERVED (0s) 0-7 (as needed)
NUM_CHANS occurrences of the following field:
Subfield Length (bits)DELETE_TMSI 1
RESERVED 1
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ACK_SEQAcknowledge sequence number. The base station sets this field to thevalue of the MSG_SEQ from the most recently received Access Channel messagerequiring acknowledgment from the mobile station addressed by this order
MSG_SEQMessage sequence number. The base station sets this field to the messagesequence number for this order.
ACK_REQAcknowledgment required indicator. The base station sets this field to 1to request from the mobile station acknowledge to this order. The base station sets thisfield to 0 to indicate that the mobile station is not required to acknowledge this order.
VALID_ACKValid acknowledgment indicator. To acknowledge the most recentlyreceived Access Channel message from the mobile station the base station sets this fieldto 1. If this order does not acknowledge the most recently received Access Channelmessage from the mobile station, the base station sets this field to 0.
ADDR_TYPEAddress type. The base station sets this field to the value shown in thefollowing table corresponding to the type of address contained in the address field:
Global Service Redirection Message, (Paging Channels)cont.
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Global Service Redirection Message, (Paging Channels)cont.
Description ADDR-TYPE
(binary)
ADDR_LEN
(octets)
Reserved 000 -
ESN 001 4 to 7
IMSI 010 5 to 7
TMSI 011 2 to 12
Reserved 100 -
BROADCAST 101 Variable
All other ADDR_TYPE values are reserved
ADDR_LENAddress field length. The base station sets this field to the number of octetsincluded in the ADDRESS field.
ADDRESSMobile station or broadcast address. The base station sets this field to themobile station or broadcast address, according to the address type specified in theADDR_TYPE field
If the ADDR_TYPE is equal to 001, the ADDRESS field has the following structure:
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Global Service Redirection Message, (Paging Channels)cont.
Sub field Length (bits)
ESN8 8 x ADDR_LEN
If the ADDR_TYPE is equal to 010, the ADDRESS field has the following structure
Sub field Length (bits)
IMI_CLASS 1
IMI Class-specific subfields 7 + 8 x (ADDR_LEN1)
If the ADDR_TYPE is equal to 011, the ADDRESS field has the following structure
Sub field Length (bits)
TMSI_ZONES If ADDR_LEN > 4 then ADDR_LEN4;
otherwise 0
TMSI_CODE_ADDR If ADDR_LEN > 4 then ADDR_LEN4;
otherwise ADDR_LEN
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General Page Message (Paging Channels)
Class 0, IMSI_S included
Class 0, IMSI_S and
IMSI_11_12 included
Class 0, IMSI and
MCCincluded
Class 0, IMSI_S,
IMSI_11_12, and MCC included
Class 1, IMSI and
MCCincluded
Class 1, IMSI_S,
IMSI_11_12, and MCC included
Class 2 with 32 bit TMSI_CODE_ADDR
(SID, NID & TMSI_ZONE not included)
Class 2 with 24 bit TMSI_CODE_ADDR
(SID, NID & TMSI_ZONE not included)
Class 2 with 16 bit TMSI_CODE_ADDR
(SID, NID & TMSI_ZONE not included)
Class 2 with 32 bit TMSI_CODE_ADDR
(SID, NID & TMSI_ZONE included)
Class 3, Broadcast
00
00
00
00
01
01
10
10
10
10
11
Page Record FormatsPage Record Formats
PageClass
(binary)
PageSubclass
(binary)
Page RecordFormat No
(decimal)
00
01
10
11
00
01
00
01
10
11
00
0
1
2
3
4
5
8
9
10
11
12
MSG_TYPE (00010001) 8
Field Length (bits)
CONFIG_MSG_SEQ 6
ACC_MSG_SEQ 6
CLASS_0_DONE 1
CLASS_1_DONE 1
TMSI_DONE 1
ORDERED_TMSIS 1
BROADCAST_DONE 1
RESERVED_ 4
ADD_LENGTH 3
ADD_PFIELD 8 x ADD_LENGTH
PAGE_CLASS 2
PAGE_SUBCLASS 2
Page-type-specific fields Page-type-specific
REESERVED (0s) 07 (as needed)
Zero or more occurrences of the following page record:
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Page Channel messages other than the General Page Message can be addressed, by means of the ADDRESS field, to
either a specific mobile station identified by its ESN (ADDR_TYPE = 001), a specific IMSI (ADDR_TYPE =
010), or a specific TMSI (ADDR_TYPE = 011).
General Page Messages can only be addressed to specific IMSIs or TMSIs.
The base station assigns the mobile station a page class and subclass which determines how it will be addressing that
mobile station in General Page Messages. If the PAGE_CLASS of a page record is 00 or 01, then this paging recordrefers to a mobile addressed by IMSI. If the PAGE_CLASS of a page record is 10, then this paging record refers to a
mobile addressed by TMSI. If the PAGE_CLASS of a page record is 11, then this paging record refers to a mobile
addressed as part of a broadcast group.
General Page Messages contain four fields, CLASS_0_DONE, CLASS_1_DONE, TMSI_DONE, and
ORDERED_TMSIS, which indicate when a personal station operating in slotted mode may stop monitoring the
Paging Channel.
The concepts of CLASS 0 and CLASS 1 have to do with the number of digits in the IMSI, and aredefined in the next slide.
CLASS_0_DONESet to 1 by the base station if all the class 0 page records or other directed messages for
mobile stations operating in slotted mode, active in this slot, and having an assigned class 0 IMSI, have been sent by
the end of this General Page Message. Set to 0 otherwise.
General Page Message (Paging Channels)cont.
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General Page Message (Paging Channels)cont.
CLASS_1_DONESet to 1 by the base station if all the class 1 page records or other directed messages for
mobile stations operating in slotted mode, active in this slot, and having an assigned class 1 IMSI, have been sent by
the end of this General Page Message. Set to 0 otherwise.
TMSI_DONESet to 1 by the base station if all the class 10 page records or other directed messages for mobile
stations operating in slotted mode, active in this slot, and having an assigned TMSI have been sent by the end of this
General Page Message. Set to 0 otherwise.
ORDERED_TMSISSet to 1 by the base station if all the class 10 page records in all the General Page
Messages sent for mobile stations operating in slotted mode, active in this slot, have the TMSI code values of the
TMSI_CODE and TMSI_CODE_ADDR fields in ascending numerical order. Set to 0 otherwise.
BROADCAST_DONESet to 1 by the base station if all the broadcast (class 11) page records, have been sent
by the end of this General Page Message. Set to 0 otherwise.
ADD_LENGTHNumber of octets in the page-message-specific fields.
ADD_FIELDAdditional page-message-specific fields.
RESERVEDUp to 7 bits (as needed) to make the total length of the message an integer number of octets.
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IMSI
MCC
MNC MSIN (Up to 10 digits)
(3 digits) (2 digits)
NMSI (Up to 12 digits)
IMSI (Up to 15 digits)
IMSI International Mobile Station Identity
MCC Mobile Country CodeNMSI National Mobile Station Identity
MNC Mobile Network Code
MSIN Mobile Station Identification N umber
Class 0 IMSI: 15 digits Class 1 IMSI: less than 15 digits
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IMSI_S
IMSI with less than 10 digits
IMSI with 10 digits
IMSI with more than 10 digits
0 0
IMSI_S2 IMSI_S1
(34 bits)
(10 digits)
IMSI_S
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IMSI_11_12
IMSI with less than 12 digits
IMSI with 12 digits
IMSI with more than 12 digits
00
IMSI_11_12
1 2 3 4 5 6 7 8 9 10 11 12
1 2 3 4 5 6 7 8 9 10 11 12
1 2 3 4 5 6 7 8 9 10 11 12 13 14
When the IMSI has 12 or more digits, IMSI_11_12 is equal to the 11th and 12th digits of the IMSI. When the IMSI hasfewer than 12 digits, IMSI_11_12 is equal to the last two digits.
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Page Records (Class 0)
MSG_SEQ 3
IMSI_S 34
Field Length (bits)
SPECIAL_SERVICE 1
SERVICE_OPTION 0 or 16
MSG_SEQ 3
IMSI_S 34
Field Length (bits)
SPECIAL_SERVICE 1
SERVICE_OPTION 0 or 16
MCC 10
MSG_SEQ 3
IMSI_S 34
Field Length (bits)
SPECIAL_SERVICE 1SERVICE_OPTION 0 or 16
IMSI_11_12 7
Class 0, Subclass 0
Class 0, Subclass 2
Class 0, Subclass 1
MSG_SEQ 3
IMSI_S 34
Field Length (bits)
SPECIAL_SERVICE 1
SERVICE_OPTION 0 or 16
IMSI_11_12 7
Class 0, Subclass 3
MCC 10
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See next series of slides
Page Records (Class 0)cont.