zte umts coverage enhancement feature guide u9.2

Coverage Enhancement WCDMA RAN

Feature Guide

Coverage Enhancement Feature Guide

ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. I


Version Date Author Approved

By Remarks

V4.0 2010-6-18 ShenWei JiangMin

2010 ZTE Corporation. All rights reserved. ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used without the prior written permission of ZTE.

Due to update and improvement of ZTE products and technologies, information of the document is subjected to change without notice.


ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. II

TABLE OF CONTENTS

1 Functional Attribute ............................................................................................1

2 Overview .............................................................................................................1 2.1 Function Introduction ............................................................................................1 2.1.1 Multi-Antenna Receive Diversity ............................................................................1 2.1.2 Multi-RRU For One Cell ........................................................................................2 2.1.3 Transmit Diversity ................................................................................................2 2.1.4 Extended Cell Range............................................................................................2 2.1.5 High-Speed Access ..............................................................................................2

3 Technical Description .........................................................................................3 3.1 Single Antenna Reception.....................................................................................3 3.2 Two-Antenna Receive Diversity.............................................................................4 3.3 Four-Antenna Reception .......................................................................................6 3.4 Multi-RRU for One Cell .........................................................................................7 3.5 Transmit Diversity ..............................................................................................11 3.5.1 Space-Time Transmit Diversity............................................................................11 3.5.2 Time Switched Transmit Diversity........................................................................14 3.5.3 Closed-Loop Transmit Diversity Mode I ...............................................................14 3.5.4 Connection of Transmit Diversity .........................................................................15 3.6 Extended Cell Range to 80Km ............................................................................16 3.6.1 Reduction of Path Loss.......................................................................................16 3.6.2 Optimization of Antenna......................................................................................20 3.6.3 Cell Searching Capability ....................................................................................22 3.6.4 AMR Code .........................................................................................................22 3.7 Extended Cell Range to 120 km ..........................................................................23 3.8 High-Speed Access ............................................................................................24 3.8.1 Doppler shift ......................................................................................................24 3.8.2 Handover Influence ............................................................................................26 3.8.3 Cell Selection and Reselection ............................................................................27 3.8.4 Baseband Frequency Offset Compensation Algorithm ..........................................27 3.8.5 Handover Optimization .......................................................................................30 3.8.6 Cell Reselection Optimization..............................................................................31

4 Parameters Related to Coverage Enhancement Control ...................................32 4.1 Parameters Related to RF Connection.................................................................32 4.1.1 Parameter List ...................................................................................................32 4.1.2 Parameter Configuration .....................................................................................33 4.2 Parameters Related to Receive Diversity .............................................................37 4.2.1 Parameter List ...................................................................................................37 4.2.2 Parameter Configuration .....................................................................................37 4.3 Parameters Related to Multi-RRU One Cell..........................................................38 4.3.1 Parameter List ...................................................................................................38 4.3.2 Parameter Configuration .....................................................................................38 4.4 Parameters Related to Transmit Diversity ............................................................38 4.4.1 Parameter List ...................................................................................................38 4.4.2 Parameter Configuration .....................................................................................39 4.5 Parameter Related to Extended Cell Range to 80Km............................................42 4.5.1 Parameter List ...................................................................................................42 4.5.2 Parameter Configuration .....................................................................................43 4.6 High speed access .............................................................................................43 4.6.1 Parameter List ...................................................................................................43


ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. III

5 Glossary ...........................................................................................................46


ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. III

FIGURES

Figure 1 Connection of Single Antenna Reception .................................................................3

Figure 2 Mechanism of Two-Antenna Receive Diversity .........................................................4

Figure 3 Connection of Two-Antenna Receive Diversity .........................................................5

Figure 4 Mechanism of Four-Antenna Receive Diversity ........................................................6

Figure 5 Connection of Four-Antenna Receive Diversity.........................................................7

Figure 6 Principle of Multi-RRU Combined Cell (1).................................................................8

Figure 7 Principle of Multi-RRU Combined Cell (2).................................................................8

Figure 8 Example on Multi-RRU Combined Cell ....................................................................9

Figure 9 STTD in QPSK Mode ...........................................................................................12

Figure 10 STTD in 16QAM Mode .........................................................................................12

Figure 11 STTD in 64QAM Mode .........................................................................................13

Figure 12 TSTD of SCH.......................................................................................................14

Figure 13 Closed-Loop Transmit Diversity Mode of DPCH/HS-PDSCH ...................................15

Figure 14 Connection of Transmit Diversity ...........................................................................15

Figure 15 Sections of Radio propagation on the Sea .............................................................16

Figure 16 Propagation Curve ...............................................................................................19

Figure 17 Connection of TMA...............................................................................................21

Figure 18 Scenario where a High-Speed UE Passes a Node B ..............................................25

Figure 19 Doppler shift when the Value of D Changes at Different Vehicle Rates ....................25

Figure 20 Frequency Offset Estimation of ZTE UMTS ............................................................28

Figure 21 Frequency Offset Compensated by ZTE UMTS Baseband Subsystem ....................29


ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. 1

1 Functional Attribute

System version: [RNC V3.09, Node B V4.09, OMMR V3.09, OMMB V4.09]

Attribute: [Optional]

Involved NEs:

UE Node B RNC MSCS MGW SGSN GGSN HLR

- - - - -

Note:

*-:Not involved.

*: Involved.

Dependency: [None]

Mutual-exclusion function: [None]

Note: [None]

2 Overview

2.1 Function Introduction

During network planning and construction, it is necessary to consider the coverage enhancement technology to the uplink/downlink according to network load and service, with a view to offsetting the deficiency of coverage capacity in a specific direction. This

document describes the main uplink/downlink coverage enhancement technologies (Two-Antenna receive diversity, Four-antenna receive diversity, Transmit diversity, Multi-RRU for one cell, and Extended Cell Range to 80km ) of ZTE UMTS in respect of

functions and usage.

2.1.1 Multi-Antenna Receive Diversity

The diversity technology is implemented by searching and utilizing the independent

multi-path signals in the radio propagation environment in nature. In short, the technology is to select two or more signals among multiple signals for merging, so as to raise the instantaneous SNR and average SNR of the receiver at the same time.

Diversity is an anti-fading technology in the field of mobile communication. It is also a powerful receiving technology that improves the radio link performance greatly.

In practice, such technologies as multi-path diversity, multi-antenna receive diversity,

and macro diversity, are used to increase the uplink coverage.

ZTEs UMTS enables multi-path diversity reception and MRC (maximal ratio

combining) of signals through a Rake receiver.



ZTEs UMTS uses the multi-antenna receive diversity technology, for example,

Two-Antenna receive diversity and four-antenna receive diversity.

ZTEs UMTS supports soft handover and softer handover.

2.1.2 Multi-RRU For One Cell

In special environments, a large number of antennas are required for covering a complicated area while too much cells may increase network management load. In this

case, it can be considered to merging multiple RRUs and their antenna coverage areas into one logic cell. In the view of Node B and RNC, these coverage areas belong to the same cell. This technology is the multi-RRU for one cell.

2.1.3 Transmit Diversity

Transmit diversity is to transmit a signal through multiple antennas of a BTS. In a fading environment, transmit diversity enables a UE to receive multi-path signals and better

signal quality, thus improving the performance of the radio communication system effectively.

ZTEs UMTS uses open-loop transmits diversity and closed-loop transmit diversity mode

1. In the open-loop mode, no feedback information is available between the UE and Node B. Open-loop transmit diversity includes Space-Time Transmit Diversity (STTD) and Time Switched Transmit Diversity (TSTD). In the closed-loop mode, the UE sends

the feedback information to Node B so as to optimize the transmission of the diversity antennas.

Open-loop t ransmit diversity requires no signaling overhead and make the mobile

stations process quickly. However, this mode does not utilize the channel information. Closed-loop transmit diversity has high performance in a low-speed moving environment, but its control mode is more complex.

2.1.4 Extended Cell Range

Due to its powerful baseband processing capability and searching capability, ZTEs UMTS ensures random access of the cells within the distance of 80 km. The ZTEs

UMTS supports the Extended Cell Range (as distant as 80 km) through various coverage enhancement technologies including multi-antenna reception, transmit diversity, and antenna feeder optimization.

2.1.5 High-Speed Access

For the high-speed access coverage, the system and the environment should be

considered comprehensively to solve various problems related to the high-speed moving, especially the Doppler shift, fast handover and the call through rate.

The 3GPP has defined three high-speed train scenarios: trains moving at a rate of 350

km per hour in open space; trains moving at a rate of 300 km/h in tunnels with multi-antennas; trains moving at a rate of 300 km/h in tunnels with leaky cables.



Based on the experience of implying the mobile technology for years, ZTE has developed a series of distinctive high-speed moving technologies such as: baseband frequency offset compensation algorithm, optimized RRM algorithm for high-speed

moving, and flexible network planning adapted to various environments,etc. These technologies can handle the high-speed WCDMA communication scenarios with rates higher than 350 km/h, and can provide abundant data and voice services to satisfy

users' requirements.

3 Technical Description

3.1 Single Antenna Reception

Receiver diversity will not be applied when only one antenna is used to receive the uplink signal. The parameter defining the type of receiver diversity (RxDiversity) should be set to "1: Single Antenna Rx", and an RF receiving cable needs to be configured, with

RF receiving cable 1 (RFRxID [1]) set to be "Antenna 1".

By default, only one antenna is configured in one RRU. Then the transmitter antenna can only be connected to the TX/RX path of the RRU, whereas the receiver antenna can

be connected to the TX/RX path or the RX path of the RRU, that means any one of these two paths could be the receiver antenna path.(as shown in Figure 1). In the figure1, the RRU transceiver (RTR) module is the transceiver, the PA is the power

amplifier module, and the duplexer filter (DF) is the duplexer and filter.

Figure 1 Connection of Single Antenna Reception



3.2 Two-Antenna Receive Diversity

Receive diversity includes multi-path diversity, multi-antenna diversity, and softer

handover. It makes no difference when the Rake receiver processes these types of diversity. The RF can receive and utilize all the energy transmitted from the multiple paths of the multiple antennas, when the corresponding demodulation multiple fingers

are allocated to the configured multi-path signals. Therefore, multi-antenna receive diversity is based on the Rake receiver.

When Two-Antenna receive diversity is used, you need to set the RxDiversity parameter

to 2:2-antenna Rx Diversity. In addition, you need to configure two receiving RF connections: configure RFRxID [1] (receiving RF connection 1) to Antenna 1, and configure RFRxID [2] (receiving RF connection 1) to Antenna 2.

Figure 2 shows the mechanism of Two-Antenna receive diversity.

Figure 2 Mechanism of Two-Antenna Receive Diversity

RF

process

RF

process

Multi-path detection and

assignation

Finger

demodulation

Symbol

level

process

RF Unit (RRU Base Band UnitBBU

U

E

Reflector

Antenna 1

Antenna 2

MRC

Two-Antenna receiver diversity works on the following principle:

1 The radio signals received by the Two-Antennas are processed by RF units respectively, and then are sent to the base band unit (BBU) of Node B.

2 The BBU receives the Rake signal and performs the subsequent processing.

The Rake receiver mainly performs the following functions:

Multi-path detection and assignation

Finger demodulation

MRC

For Two-Antenna receive diversity, the multi-path detection and assignation module searches the Two-Antennas at the same time, merges the lag energy values of the Two-Antennas, and assigns demodulation fingers for some multi-path delays in descending

order of the energy.



For the assigned demodulation fingers, the Rake receiver centrally performs the following demodulation operations: descrambling, dispreading, channel estimation and compensation, and frequency offset estimation and compensation.

Finally, the Rake receiver performs the MRC operation for the demodulation results of all paths, and performs the subsequent symbol level processing.

Figure 3 shows the hardware connection of Two-Antenna receive diversity.

Figure 3 Connection of Two-Antenna Receive Diversity

T 2R

DF

RTR+PA

RRU/RSU

ANT1

R&T

ANT2

R

BBU

The RRU transceiver (RTR) serves as a transceiver. PA refers to the power ampli fier module, DF refers to the duplexer and filter, ANT1 refers to Antenna 1, and ANT2 refers to Antenna 2.

By default, a single RRU and single antenna are configured. Therefore, you need to configure the RF connection for the Rake receiver before configuring double antennas or multiple antennas. The detailed procedure is as follows:

3 Add the rack table that contains the new RRU to the configuration. The rack table contains the following parameters: Rack .RackNo and Rack .RackType (it depends on the product model of the RRU/RSU module).

4 Add the corresponding topology table. Note that Rack Topology. RackNo, RackTopology.ShelfNo, and RackTopology.SlotNo should be configured to the data of the rack that accommodates the BBU. RackTopology.PortID should be set to the

number of the port between the FS board of the BBU and the TX/RX of the RRU. RackTopology.ChildRackNo, RackTopology.ChildShelfNo, and RackTopology.ChinldSlotNo reflects the information on the newly added RRU rack.

RackTopology.ChildPortID should be set to the number of the optical port between the RRU and BBU, and RackTopology.TopologyType (the topology type of the RRU) to Star or Chain.



5 Add the corresponding RF connection table. The table contains RFConnection .RFGroupID and RFConnection.RTSign. For the RF connection of main antennas, RFConnection.RTSign can be set to 0: Transmit or 1: Receive.

For the RF connection of diversity antennas, RFConnection.RTSign should be set to 1: Receive. RFConnection.RFType and RFConnection.ResourceType should be set as needed.

6 Add the corresponding RF central frequency point table. RFCentralFrequencyPoint..RackNo, RFCentralFrequencyPoint.ShelfNo, and RFCentralFrequencyPoint.SlotNo should be set to the rack information configured

at Step 1 and Step 2. RFCentralFrequencyPoint.RadioMode should be set to WCDMA. RFCentralFrequencyPoint (.OperBand) and RFCentralFrequencyPoint.CentralFreq should be set as planned.

3.3 Four-Antenna Reception

Figure 4 hows the mechanism of four-antenna receive diversity.

Figure 4 Mechanism of Four-Antenna Receive Diversity

RF

process

RF

process

Symbol

level

process

RF Unit1 (RRU Base Band UnitBBU

U

E

Reflector

Antenna 1

Antenna 4

MRC

RF

processAntenna 2

RF

processAntenna 3

Finger

demodulation

Multi-path detection and

assignation

RF Unit 2(RRU

Four-antenna receiver diversity works on the following principle:

1 Four-antenna receive diversity is implemented through two RF units. Each RF unit inputs two channels of antenna signals, which are processed by two independent

RF channels of the RF units and then are sent to the BBU of Node B.

2 The BBU performs the following Rake processing:

The multi-path detection and assignation module searches four antennas at the

same time, merges the lag energy values of Two-Antennas of each RF unit respectively, and thus obtains two groups of combined energy values. Then, the module assigns demodulation fingers in descending order of the energy

respectively. The module obtains two groups of assignation results, which correspond to the two Two-Antenna groups of the two RF units respectively.



When four-antenna receive diversity is used, you need to set the RxDiversity parameter to 3:4-antenna Rx Diversity. You need to configure four receiving RF connections at the same time:

Set RFRxID[1] (receiving RF connection 1) to Antenna 1




The subsequent processing is the same as that for Two-Antenna receives diversity. Figure 5 shows the hardware connection of four-antenna diversity. It shows that the hardware configuration of four-antenna diversity is equal to the configuration of multiple

suites of Two-Antenna diversity.

Figure 5 Connection of Four-Antenna Receive Diversity

2RX

DF

RTR

RRU/RSU

TX 2RX

DF

RTR+PA

RRU/RSU

ANT3

R&T

ANT4

R

ANT1

R

ANT2

R

BBU

The RRU transceiver (RTR) serves as a transceiver. PA refers to the power amplifier module, DF refers to the duplexer and filter, ANT1 refers to Antenna 1, ANT2 refers to

Antenna 2, ANT3 refers to Antenna 3, and ANT4 refers to Antenna 4.

The procedure of adding new RF connections to four-antenna receive diversity is the same as that of adding new RF connections to two-antenna receive diversity.

3.4 Multi-RRU for One Cell

A multi-RRU combined cell is to merge the multiple cells covered by multiple RRUs into one cell. From another point of view, it is equal to the following process:

The coverage area of one cell is divided into multiple sectors or multiple areas,

The sectors or coverage areas use different antennas for receiving signals,



The signals are combined in the baseband.

The transmitting signals of all sectors or coverage areas are the same.

Figure 6 shows the detailed signal processing flow.

Figure 6 Principle of Multi-RRU Combined Cell (1)

Downlink

signal

generation

Downlink

signal

copy

RRU

RRU

RRU

RAKE

finger

demodulation

Multi-path

detection and

assignation

MRC

Symbol rate

process

and

higher layer

process

RNC

BBU

...

...

As shown in Figure 6, the same carriers of three RRUs are combined into one cell, and the coverage areas of these three RRUs are different from each other. In the uplink direction, the signals received by multiple RRUs are sent to the BBU respectively. The

BBU performs multi -path detection and RAKE demodulation for the signals of each RRU, performs the MRC operation for the signals of each demodulated RRU (only one RRU or multiple RRUs have signals possibly), and then performs the subsequent processing. In

the combined cell, it is obvious that the handover between RRU coverage areas is complete during multi-path detection and assignation without the signaling exchange and control of the RNC and UE. In the downlink direction, the generated downlink

signals are copied and sent to multiple RRUs, thus attaining the effect of total -cell transmitting.

Figure 7 Principle of Multi-RRU Combined Cell (2)

Downlink

signal

generation

Downlink

signal

copy

RRU

RRU

RRU

RAKE

finger

demodulation

Multi-path

detection and

assignation

MRC

Symbol rate

process

and

higher layer

process

RNC

BBU

...

RRU

RRU

RRU

Weighted

combination

Weighted

combination

Weighted

combination

...

For a cell comprising more RRUs, the signals of the receiving antennas of some RRUs

can be weighted according to the receiving power, be combined into one data stream, and then undergo subsequent detection and demodulation with a view to reducing the resource consumption of multi-path detection. Figure 7 shows the merge of six RRUs.

The coverage areas of these RRUs can be different from each other.



The multi-RRU merge technology has the following advantages:

Decrease the number of cells in a mobile communication network, simplify network

planning and adjacency configuration in the RNC, reduce the frequency of handover

controlled by the RNC greatly, implement the handover between coverage areas

inside a cell through Node B, and improve subscriber experience and system

performance.

One cell is covered by multiple RRUs and with their antennas. The coverage area of

one cell can be so flexible as not to be limited to sector coverage or round coverage.

It well caters to the coverage needs in special scenarios, for example, a complex

urban area, inside a building, or along a traffic route.

Attain the space division multiplexing effect in the uplink division: The uplink

throughput of one cell can be equal to several times as high as that of a

conventional cell.

The downlink signals of the same cell are transmitted by multiple RRUs. Downlink

diversity gain can be attained in the overlap coverage area of different RRUs, thus

improving the network coverage quality and raising the HSDPA throughput of each

individual UE.

Figure 8 shows an example of cell coverage. Assume that omni -directional round cells are not suitable to coverage in this dense urban area due to the obstruction of buildings,

and if a conventional coverage method is used, In Figure 8, each diamond-shaped area needs to be covered by one cell, and thus a total of 12 cells are required. Through the multi-RRU merge technology, a hexagonal area (approximate to a round in practice),

which comprises three adjacent diamond-shaped areas (approximate to a sector in practice), is used as the coverage area of one cell. Three RRUs and their antennas are used to cover three diamond-shaped areas. As a result, only four cells are enough for

the same network coverage. Generally, the technology decreases the number of required cells greatly, and reduces the frequency of handover controlled by the RNC.

Figure 8 Example on Multi-RRU Combined Cell



Cell 1

Cell 4

Cell3

Cell 2

S43

S11

S12

S13

S21

S22

S23

S31

S32

S33 S42

S41

Compared with the traditional sector networking mode, the merge technology has the following disadvantages:

While the number of required cells is decreased and downlinks UPAs and code

resources are scheduled basing on a cell, the downlink system throughput is

reduced greatly (although the average peak throughput per UE can be raised).

Downlink signals are transmitted by multiple RRUs at the same time, but UEs are

usually distributed in the coverage area of one RRU, thus multiplying the downlink

power consumption.

If there are a large number of RRUs, the signals of these RRUs undergo weighted

combination before descrambling and dispreading. As a result, the combined RRUs

interfere with each other, thus affecting the receiving performance.

ZTE s UMTS supports five types of multi-RRU cell configuration (two RRUs, three RRUs, four RRUs, five RRUs, and six RRUs) as follows:

2-RRU Cell: Configure RxDiversity to 4: 2-RRU Cell and configure four receiving

antenna parameters (configure RFRxID[1] to the main antenna of the first RRU,

configure RFRxID[2] to the diversity antenna of the first RRU, configure RFRxID[3] to

the main antenna of the second RRU, and configure RFRxID[4] to the diversity

antenna of the second RRU,). Configure TxDiversity to 3: 2-RRU Cell, and

configure two transmitting antenna parameters (configure RFTxID[1] to the

transmitting main antenna of the first RRU, and configure RFTxID[2] to the

transmitting main antenna of the second RRU.

3-RRU Cell: Configure RxDiversity to 5: 3-RRU Cell and configure six receiving

antenna parameters (configure RFRxID[1] to the main antenna of the first RRU,

configure RFRxID[2] to the diversity antenna of the first RRU, configure RFRxID[3] to

the main antenna of the second RRU, configure RFRxID[4] to the diversity antenna

of the second RRU, configure RFRxID[5] to the main antenna of the third RRU, and



configure RFRxID[6] to the diversity antenna of the third RRU). Configure TxDiversity

to 4: 3-RRU Cell, and configure three transmitting antenna parameters (configure

RFTxID[1] to the transmitting main antenna of the first RRU, configure RFTxID[2] to

the transmitting diversity antenna of the second RRU, and configure RFTxID[3] to

the transmitting main antenna of the third RRU.

4-RRU Cell: Configure eight receiving antennas and four transmitting antennas (the

receiving antennas should be configured to receiving RF connections 1 to 8, and

the transmitting antennas should be configured to transmitting RF connections 1 to

4).

5-RRU Cell: Configure ten receiving antennas and five transmitting antennas (the



5).

6-RRU Cell: Configure 12 receiving antennas and six transmitting antennas (the



6).

The procedure of adding new RF connections to the multi-RRU combined cell is the same as that of adding new RF connections to two-antenna receive diversity.

3.5 Transmit Diversity

This section describes the technical principle of transmit diversity in detail, including

Space-Time Transmit Diversity (STTD), Time-Switched Transmit Diversity (TSTD), and closed-loop transmit mode 1.

3.5.1 Space-Time Transmit Diversity

For STTD, the antenna data is encoded through the space time block and is sent to the main antenna and diversity antenna respectively. The space time block code varies with the modulation mode. Figure 9 shows the STTD codes of QPSK, 16QAM, and 64 QAM.

bi, i=0, 1, 2 are channel bits. For the AICH, E-RGCH, and E-HICH, the ib means ib .

For other channels, ib is defined as follows:

If ib = 0, ib = 1

If ib = 1, ib = 0

If ib ib = other values, ib = ib



Figure 9 STTD in QPSK Mode

b1b0b2 b3Symbols

STTD encoded symbols for

antenna 1 and antenna 2

Antenna 2

b0 b1 b2 b3

b0 b1 b2 b3 Antenna 1

Figure 10 STTD in 16QAM Mode



b4 b5 b6 b7 b1b0 b2 b3Symbols



Antenna 1

Antenna 2

b0 b1 b2 b3 b5b4 b6 b7

b0 b1 b2 b3 b5b4 b6 b7

Figure 11 STTD in 64QAM Mode

Symbols



Antenna 1

Antenna 2

b0 b1 b2 b3 b5b4 b6 b7 b9b8 b10 b11

b0 b1 b2 b3 b5b4 b6 b7 b9b8 b10 b11

b9b8 b10 b11 b0 b1 b2 b3 b5b4b6 b7

If space time transmit diversity is used, you need to set TxDiversity to 2: Two-Antenna transmit diversity, set RFTxID[1] to Antenna 1, and set RFTxID[1] to Antenna 2.

To use space time transmit diversity, you need to configure the RNC appropriat ely, for example, set TxDivInd to 1: Active.



If configuring transmits diversity for a dedicated channel, you need to set PCCPCH.SttdInd of the P-CCPCH to 1: Active, and set PSCH.SttdInd of the P-SCH to 1: Active. If configuring transmit for a dedicated channel, the transmit diversity of the

preceding three physical channels must be activated.

To use the transmit diversity of the DPCH/F -DPCH, you need to set TxDivMod to STTD.

To use the transmit diversity of the S-CCPCH, you need to set SCCPCH.SttdInd to 1:

Active.

To use the transmit diversity of the S-CPICH, you need to set SCPICH.SttdInd to 1: Active.

To use the transmit diversity of the AICH, MICH, and PICH, you need to set AICH.SttdInd, MICH.SttdInd, and PICH.SttdInd to 1: Active.

3.5.2 Time Switched Transmit Diversity

TSTD is only used for a SCH, as shown in follow figure. Cp refers to the primary synchronization code (PSC), and cs

i,k refers to the secondary synchronization code

(SSC). i (= 0, 1, 63) refers to the number of scrambling groups. k (= 0, 1, 14) refers to

the slot number. If the slot number is an even number, the PSC and SSC are transmitted by Antenna 1. If the slot number is an odd number, the PSC and SSC are transmitted by

Antenna 2. If the P-CCPCH uses the STTD codes, a = a +1. Otherwise, a = 1.

Figure 12 TSTD of SCH

Antenna 1

Antenna 2

acsi,0

acp

acsi,1

acp

acsi,14

acp

Slot #0 Slot #1 Slot #14

acsi,2

acp

Slot #2

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

(Tx OFF)

If TSTD is used, you need to set SCH.TstdInd to 1: Active.

3.5.3 Closed-Loop Transmit Diversity Mode I

Closed-loop t ransmit diversity mode 1 is mainly used for a dedicated physical channel (DPCH/HS-PDSCH), as shown in Figure 13. After being spread and scrambled, the

DPCH/HS-PDSCH data is divided into master antenna data stream and diversity antenna data stream, which are multiplied by w1 and w2 respectively, and then are sent to the antennas. w1 and w2 are generated from the feedback information bits of the

uplink DPCCH that Node B reads. 2/11 w , 21 j

w2

. For closed-loop transmit

diversity mode 1, the Two-Antennas use orthogonal pilot symbols. You need to set



TxDiversity to 2: Two-Antenna transmit diversity, set RFTxID[1] to Antenna 1, and set RFTxID[1] to Antenna 2.

Figure 13 Closed-Loop Transmit Diversity Mode of DPCH/HS-PDSCH

Weight Generation

w 1

Determine weight info message from the uplink

w 2

DPCH/ HS-PDSCH

Spread/scramble

Ant 1

Ant 2

CPICH 1

2

w 1

w 2

CPICH

3.5.4 Connection of Transmit Diversity

Figure 14 shows the transmit diversity connection.

Figure 14 Connection of Transmit Diversity

R

DF

RTR+PA

RRU/RSU

T R

DF

RTR+PA

RRU/RSU

ANT2

R&T

ANT1

R&T

BBU

T



The RTR serves as a transceiver. PA refers to the power amplifier module, DF refers to the duplexer and filter, ANT1 refers to Antenna 1, and ANT2 refers to Antenna 2.

The procedure of adding new RF connections to the transmit diversity is the same as

that of adding new RF connections to two-antenna receive diversity.

3.6 Extended Cell Range to 80Km

The scenarios of extended cell include seas, deserts, grasslands, mountainous region , and mountains; ZTE s UMTS supports the cells as distant as 80 km. When configuring the extended Cell Range 80 km, you need to set dwCellRadius to 80,000 m.

To attain a better coverage effect, the following coverage enhancement measures can be taken:

Reduce the path loss by adjusting the mounting height o f antennas and lowering the

carrier band.

Improve the sensitivity by using directional antennas and tower mounted amplifiers

and reducing the noise figure of the receivers.

Improve the processing gain: For example, use the AMR codes.

Improve the baseband processing capability to enhance the cell search capability .

Reduce the fading margin through various diversity technologies (multi -path

diversity, antenna diversity, and macro diversity)

3.6.1 Reduction of Path Loss

The typical application of extended cell is sea coverage. Depending on the coverage

distance, the radio propagation environment on the sea is divided into three sections: A, B, and C. Figure 15 shows its schematic diagram.

Figure 15 Sections of Radio propagation on the Sea



The following shows the details:

i Section A: The distance from the BTS to its visual range point is set to d1.

ii Section B: The distance from the visual range point of the BTS to the combined visual range point of the BTS and UEs is set to d2.

iii Section C: The distance of the shadow area beyond the combined visual range point of the BTS and UEs is set to d.

1 Formula of line-of-sight propagation loss

The propagation distance of radio electromagnetic waves on the sea can exceed the visible distance through diffraction. The earth is a sphere. Assume that the mounting height of the BTS is Ht meters and the height of UE is Hr meters. The

combined maximum visible distance (line-of-sight distance) of the BTS and UE is as follows:

)(2 rt HHRd (km) (1)

R refers to the radius of the earth. Considering the impact of atmospheric refraction on the propagation of radio electromagnetic waves, the equivalent earth radius Re is usually used instead of R. In the conditions of standard atmospheric refraction,

Re = 8,500 km. Therefore, Formula (1) is changed into the following formula:

)(12.4 rt HHd (km) (2)



The radio propagation environment on the sea is divided into three sections: A, B, and C.

Section A: The distance from the BTS to the visual range point is set to d1.

tHd 12.41 (km) (3)

Section B: The distance from the visual range point of the BTS to the combined visual range point of the BTS and UEs is set to d2. Based on Formula (2), the following formula can be derived:

rHd 12.42 (km) (4)

Section C: The shadow area beyond the combined visual range point of the BTS

and UEs, that is, the area with the propagation distance beyond d1+d2.

2 Formula of path loss during radio propagation

Section A:

Within the propagation distance of Section A, the radio propagation environment is very good on the sea and is similar to the propagation environment in free space. The mounting height of the BTS and height of UEs have little impact on propagation

path loss, but have some impact on applicable distance and slope of path loss. The component of reflected waves is smaller than that of direct waves, and has little impact on the prediction of statistical median of the receiving level. Therefore, it can

be ignored. For Section A, the formula on propagation path loss is as follows:

)lg(10lg2044.32 kmp dfL (5)

where,

Lp refers to the propagation path loss on the sea;

dkm refers to the distance (km) between the test point and the BTS; dkm d1.

f refers to the carrier frequency (MHz).

refers to the slope of path loss. Its value range is 2.6 to 3.4.

Section B:

Section B is a transition from the approximate free space to the shadow globe area.

At the combined visual range point of the BTS and UEs, the additional diffraction loss is about 6 dB. If the accuracy of prediction is ensured, the formula on propagation path loss in Section B is as follows:

21 /)(6)lg(10lg2044.32 ddddfL kmkmp (6)

where,

the parameters are the same as those of Section A, for example, d1dkmd1+d2.

Section C:



Section C is in the shadow globe area. You need to refer to the diffraction loss model and revise the model properly. In addition, you need to consider the environmental features of radio propagation on the sea and the operability of

coverage prediction. The formula on propagation path loss is as follows:

vvkmp edfL )62.045.0(5.0lg20)lg(10lg2044.32 (7)

where,

L refers to the wavelength (km).

)(()(2

)sin(sin)sin(1R2121

e

ddddd

dv

km

km

(8)

Re refers to the equivalent earth radius when the impact of atmospheric refraction on radio electromagnetic waves is taken into account. In the condition of standard

atmospheric refraction, Re = 8,500 km.

= (d1+d2)/Re: It refers to the included angle of the combined visual range of the BTS and UEs to the revised earth model (unit: radian).

= [dkm-(d1+d2)]/Re: It refers to the included angle between the test point and the combined visual range point of the BTS and UEs to the revised earth model (unit: radian).

The parameters are the same as those of Section A, for example, dkm d1+d2.

3 The total propagation loss is equal to the sum of propagation loss in Sections A, B, and C.

Assume that the preceding path loss model is used. Figure 16 shows a typical extended cell link propagation curve.

Figure 16 Propagation Curve



Section A is the line-of-sight propagation range and is also the main coverage area of over-distance coverage. To widen the line-of-sight propagation range, the most effective means is to raise the altitude height of the BTS antenna and altitude height of the UE

antenna, and reduce the carrier frequency. In practice, it is difficult to stipulate the altitude height of UEs by force. Therefore, the effective means is to raise the altitude height of the BTS antenna. Additionally, it is also an effective means to reduce the

carrier transmit frequency. For example, assume that the altitude height of the UE antenna is 3 meters. To ensure the coverage distance of 80 km, the altitude height of the BTS antenna should be 310 meters (in the frequency band of 2.1 GHz) or 260

meters (in the frequency band of 900 MHz).

3.6.2 Optimization of Antenna

ZTE UMTS extended cell solution considers the gain of directional antennas. A high-

gain directional antenna can be used to raise the receiving gain and the coverage distance significantly.

A directional antenna brings a far higher gain than an omni directional antenna

(usually by 6 to 7 dB). Therefore, the coverage radius of a macro cell directional

BTS is far greater than that of an omni directional BTS.

A directional transmitting antenna is intended to improve the efficient utilization of

the transmitted power and raise the confidentiality. A directional receiving antenna

is intended to enhance the immunity from interference and raise the coverage

distance.



The actual gain of a directional antenna is related to the angle o f the antenna.

Usually, the smaller the lobe width is, the higher the gain is and the longer the

coverage distance is. The smaller the lobe width is, the more cells are required.

Figure 17 Connection of TMA

7/8 Feeder Cables

Jumpers

Jumpers

Tx/RxTx/Rx Div

Tx/Rx DivTx/Rx-45+45



Tx/RxTx/Rx Div

Tx/Rx Tx/Rx Div

TMA TMA TMA

ANTENNNA

ANTENNNA

ANTENNNA

Sector1 Sector2 Sector3

Node B

UMTS

A TMA is used to amplify the uplink signals. Usually, it is installed between the main

feeder and the upside jumper (the 1/2 jumper connected to the antenna) so as to offset the deficiency of the uplink during the balanced budget between the uplink and downlink.

ZTE s extended cell solution fully considers the functions and advantages of the TMA,

and uses the TMA technology to avoid system noise deterioration caused by over length of the feeder and improve the system sensitivity. As an important coverage enhancement means, the TMA technology is widely applied. It is mainly used in



extended cell scenarios, for example, suburban areas, rural areas, sea surface, and deserts.

Customers can select the electrical down tilt antenna and TMA solution for the AISG

interface. The solution allows you to adjust the down tilt angle of the antenna and TMA gain through remote or local control software, thus facilitating fine adjustment and network optimization.

3.6.3 Cell Searching Capability

For an extended cell, the greater the cell radius is, the larger the multi-path search window of the Node B uplink is and the more search resources have to be consumed.

ZTE s Node B baseband processing board uses the ASIC chip with proprietary intellectual property. The ASIC chip is so designed as to consider the search capability of the extended cell. ZTE s baseband processing board supports the baseband

processing capability and search capability of the over -distance (80 km) coverage cell and reserves the PRACH preamble search and message demodulation resources without occupying the CE resources of the baseband.

3.6.4 AMR Code

The bit rate affects the uplink coverage. If the bit rate is very high, the processing gain is very low and the coverage area is very small. An AMR vocoder can be used to raise the

coverage area of the voice service effectively. The AMR vocoder is a single voice codec. Its source rate can be 12.2 (GSM-EFR), 10.2, 7.95, 7.40 (IS-641), 6.70 (PDC-EFR), 5.90, 5.15, and 4.75kbit/s.

Dynamic AMR adjustment is to adjust the rate of the uplink/downlink AMR service dynamically to adapt to the ever-changing radio environment. In the UMTS, the radio environment between the UE and BTS is constantly changing. When the UE moves to

the edge of the coverage area or i f the radio environment is bad, the BTS or UE transmits higher power through closed-loop power control so as to ensure the QoS of the AMR service. As a result, the power is further raised, the radio environment is further

deteriorated, and the system capacity is reduced. Furthermore, the QoS cannot be ensured even if the power is raised to an ultimate value. In this case, you can lower the AMR, offset the deterioration of the radio environment through high spreading gain, and

reduce the power overhead. If the radio environment between the UE and BTS is very good and if the transmit power of the BTS or UE is very low, you can raise the AMR to provide a higher QoS so long as the experience of other subscribers or system

performance is not affected.

ZTE s UMTS supports the dynamic AMR adjustment based on the transmit power of the dedicated channel:

When the transmit power of the uplink UE is very high, the uplink AMR is reduced at

the UE side under the control of the RNC.

When the dedicated transmit power of the downlink Node B is very high, the

downlink AMR is reduced at the CN side under the control of the RNC.

If the transmit power of the uplink UE is very low and system load is very low, the

uplink AMR is raised at the UE side under the control of the RNC.



If the dedicated transmit power of the downlink Node B is very low and system load

is very low, the downlink AMR is raised at the CN side under the control of the RNC.

The RNC sends the TFC CONTROL message to the UE so as to control the uplink AMR

at the UE side. The RNC sends the IUUP rate control frame to the CN so as to control the downlink AMR at the CN side.

You can attain the link budget gain by reducing the AMR. The calculation formula is as

follows:

10

3

10

3

102.12)/(_

102.122.12(10log*10_

dB

dB

skbAMRbitrate

AMRGain

For the 12.2-Kbps AMR voice service, the power difference between the DPCCH and

DPDCH is -3 dB. When the AMR is varying, the power of the DPCCH remains unchanged. When the AMR goes down, the power of the DPDCH is reduced.

Table 1 shows the mapping between the AMR and the gain of the 12.2 -Kbps voice

service.

Table 1 Mapping Between AMR and Coverage Gain

AMR (Kbps) Coverage Gain (dB)

12.2 0

10.2 0.5

7.95 1.15

7.4 1.32

6.7 1.55

5.9 1.83

5.15 2.11

4.75 2.27

The coverage gain varies with the coverage scenario. The coverage gain is mainly related to the path loss factors. For over-distance coverage, the coverage gain varies

with the height of the BTS antenna.

3.7 Extended Cell Range to 120 km

The Extended Cell Range scenarios include seas, desserts, grasslands, plains, and mountains. ZTE UMTS equipments support the Extended Cell Range to 120 km. To configure such a cell, you need to set the dwCellRadius parameter to 120,000 m.

The description of the technology used for 120 km Extended Cell Range is referred to that for Extended Cell Range to 80 km.



3.8 High-Speed Access

Comparing with the communications in standstill or low-speed moving, there are more

problems involved in the high-speed moving conditions. The main influences are the Doppler shift and the fast handover. The higher the moving speed is ,the more influence there are. And its more difficult to solve that problem and need more technical

requirements correspondently.

Compared with the common access environment, the high-speed access environment has the following features:

1 Propagation model and channel environment

The propagation environment and channel environment of high-speed trains are similar to those of expressways. The propagation environment outside a train is

similar to that in rural scenarios. Similarly, there is great probability of a direct path between a UE and a Node B; there is little time delay spread and less multi-path(except for the mountainous areas); and the beam-forming gain of a smart

antenna is supposed to be high.

2 Vehicle loss

Since the users are inside the high-speed trains, the penetration loss of the vehicle

should be considered during coverage planning. The penetration loss is generally 1015 dB for a common train. For a high-speed train like the one moving from Guangzhou to Shenzhen, the penetration loss is about 1520 dB according to the

test results. The penetration loss brings great challenges on the continuous coverage.

3 High moving speed of the terminals

The moving speed of a UE is generally 150200 km/h Sometimes it may arrive to 250 km/h in some railway sections. In the coming years, the moving speed of a UE could be 300350 km/h. At such speed, the Doppler shift is more than 400 Hz. Both the Node B and the UE must support the dynamic phase compensation to meet the

Quality of Service (QoS) requirements.

4 Users distribution

The users in high-speed trains are distributed inside the passenger carriages and

are moving along with the train. The handover and the cell reselection are rather frequently. Therefore, Node B resources are occupied in a burst manner.

5 Special environments such as railway tunnels

There are more railway tunnels than road tunnels. In general, railway tunnels are much longer than road tunnels. They need special coverage design.

3.8.1 Doppler shift

In high-speed coverage scenarios, the Doppler effect has the greatest influence on the performance of the UMTS system. The wavelengths of the received signals are changed

due to the relative motion of the signal source and the receiver. This is called the Doppler effect. In mobile communication systems, especially in high-speed scenarios,



the Doppler effect is even more obvious. The frequency offset caused by the Doppler effect is called Doppler shift, which is expressed by the following formula:

cos vC

ffd

Where:

is the inclined angle between the moving direction of the UE and the signal propagation direction;

v is the moving speed of the UE;

C is the propagation speed of electromagnetic waves;

f is the carrier frequency, which is about 2 GHz.

Assume a high-speed UE passes a Node B,the scenario is as shown in the following figure.

Figure 18 Scenario where a High-Speed UE Passes a Node B

When the carrier frequency f and the moving speed v are fixed, the Doppler shift will be

changed with cos. In addition, since the UE adjusts its transmitting frequency according to its receiving signal from the Node B, a double Doppler shift will be generated for the Node B. Therefore, the fd can be further expressed by the following formula:

222

22

dtvC

tvffd

The following figure shows a tendency curve of the Doppler frequency offset that changes with the value of d at different vehicle rates.

Figure 19 Doppler shift when the Value of D Changes at Different Vehicle Rates

v

d r

x

y

Node B

UE



As can be seen from the figure above, the Doppler shift has the following features:

1 When the UE is moving, the Doppler shift changes as the UE's location changes.

2 The maximum Doppler shift received by the Node B is in proportion to the moving speed of the UE. The more quickly the UE moves, the greater the frequency offset

is, as shown in Table 1.

Table 2 Relationship Between the Doppler shift and the Vehicle Rates

Vehicle Rate (km/h) Maximum Doppler shift (Hz)

120 480

300 1150

350 1340

430 1600

3 The farther the UE is away from the Node B ,the more Doppler shift is The frequency offset would be 0 but the frequency offset has the fastest change when

the UE passes the Node B.

3.8.2 Handover Influence

In high-speed scenarios, the handover performance will be much affected. To guarantee

the users ' seamless mobility and QoS, the system design should ensure that the time for the UE to pass the handover zone is longer than the handover processing time.



Otherwise, the handover procedure cannot be completed and the user's QoS will be degraded or even call drops,

The handover In WCDMA systems include int ra-frequency soft handover, inter-

frequency hard handover, and inter-system handover. They have different features and different applications in high-speed scenarios.

Soft handover is a particular policy of WCDMA systems. A user may establish and

maintain multiple wireless connections with multiple cells so as to obtain a greater link gain. In high-speed scenarios, the system needs to provide a greater cell coverage radius than in common scenarios, so as to avoid frequent handover. A large handover

zone, however, should be guaranteed among cells to ensure the users in macro diversity as much as possible to increase the macro diversity gain, and to guarantee users' QoS and seamless mobility accordingly. In general, it takes about 400 to 800

milliseconds to process soft handover. For this reason, the handover zone should meet at least the requirements given in Table 2 at different moving rates.

Table 3 Minimum Handover Distance Required At Different Moving Rates

Scenario Rate Handover Distance

Expressway 120 km/h 26.67 m

High-speed railway 300 km/h 66.67 m

High-speed railway 350 km/h 77.78 m

Magnetic levitation railway 450 km/h 100.01 m

3.8.3 Cell Selection and Reselection

In high-speed scenarios, network problems such as user registration failure and cell reselection failure may easily occur. These problems occur mostly because the camp-on

time of the UE is shorter than the duration of the cell reselection procedure. In general, the planned cell radius is large in high-speed scenarios and a user should be able to complete the cell reselection procedure in a cell. In areas where the coverage of one cell overlaps that of another cell, the cell reselection procedure may fail if the UE is moving

too fast. This cell reselection failure, however, does not much affect the users experience unless he/she is making or receiving a call at that moment. To avoid this problem, the cell reselection procedure should be shortened as much as possible. This

involves the reading of system messages, of which the length and repetition period are both factors affecting the cell selection.

3.8.4 Baseband Frequency Offset Compensation Algorithm

The Doppler shift is often very great for the users moving at high speed. Estimating and correcting this frequency offset to the transmitter is a mandatory function of the Node B s

receiver. Otherwise, the link performance will be greatly affected. In addition, the Node B receiver must solve the fast changing of frequency offset, that is, it must rapidly adapt to the changing speed of frequency offset and effectively make compensation.

The baseband frequency offset compensation algorithm of the Node B is usually divided into two types: frequency offset estimation and compensation in the random access procedure; frequency offset estimation and compensation for dedicated channels. These

two types greatly differ from each other.



In the access procedure of a Code Division Multiple Access system, the frequency offset estimation and compensation in the random access procedure should attain a tradeoff between resources and performance. When decoding the preamble information,

generally the system simultaneously performs frequency offset compensation and decoding by setting multiple fixed frequencies offset compensation values, t hen determines the frequency offset compensation value with which the decoding results has

the highest preamble energy, and then uses this value to make frequency offset compensation in the access message decoding procedure. When the moving speed of a magnetic levitation train reaches 430 km/h, the maximum Doppler frequency offset is

approximately 2000 Hz. If the system uses the current random access frequency offset estimation and compensation method, usually more than seven preset frequency offset compensation values need to be set. This involves a huge waste of hardware resources,

because usually only three preset frequency offset compensation values are set in wireless scenarios. Even so, the estimated frequency offset value is not accurate enough. To solve this problem, ZTE has developed an enhanced frequency offset

estimation method, which can guarantee better frequency offset estimation performance while greatly saving preamble check resources and can be flexibly applied to the configuration of coherent integration parameters.

The frequency offset estimation and compensation algorithm for dedicated channels should focus on the speed and range of frequency offset tracking. For example, the channel model for high-speed trains given in 3GPP R7 comprehensively takes into

account the speed and range of frequency offset tracking, as described in Table 3 below.

Table 4 Parameters in High-Speed Train Scenarios

Parameter Value

Scenario 1 Scenario 2 Scenario 3

sD 1000 m Infinity 300 m

minD 50 m - 2 m

K - 10 dB -

v 350 km/h 300 km/h 300 km/h

df

1340 Hz 1150 Hz 1150 Hz

In the table above, 2sD is the farthest distance in m from the train to the Node B,

minD is the distance in m from the Node B to the rail, and v is the moving velocity

per hour of the train.

ZTE UMTS baseband subsystem employs a frequency offset compensation algorithm

independently developed by ZTE to ensure that the frequency offset estimation is within a reasonable range and the changes of the frequency offset could be quickly tracked. The figure below shows the obtained frequency offset tracking results.

Figure 20 Frequency Offset Estimation of ZTE UMTS



The figure 21 shows the actual frequency offset after being compensated by ZTE UMTS baseband subsystem. As can be seen, the estimated value of frequency offset well coincides with the actual value of frequency offset, and the maximum frequency offset

estimation error is less than 300 Hz.

Figure 21 Frequency Offset Compensated by ZTE UMTS Baseband Subsystem



3.8.5 Handover Optimization

Soft handover is a particular policy of WCDMA systems. A user may establish and maintain multiple wireless connections with multiple cells so as to obtain a gre ater link gain. In high-speed scenarios, the system needs to provide a greater cell coverage

radius than in common scenarios, so as to avoid frequent handover. A large handover zone, however, should be guaranteed among cells to ensure the users in macro diversity as much as possible in order to increase the macro diversity gain and to

guaranteeing users' QoS and seamless mobility accordingly.

In addition, the handover performance could be improved by configuring the handover parameters. The 1A (RptRange) configuration can be easily triggered, whereas it is

much more difficult to trigger the 1B (RptRange) configuration, so that the radio links are in macro diversity as much as possible.

The time for triggering event reports is designed to smoothen the measurements and to

avoid erroneous event reports caused by burst signals. In high-speed scenarios, the TrigTime parameter can be set to a small value for 1A events so as to timely responds to the signal changing. For 1B events, it can be set to a large value so that the

corresponding link will be removed from macro diversity only when the signal quality of the link is really poor and thus the user's macro diversity gain is guaranteed as much as possible.

In the case of inter-frequency hard handover and inter-system handover, the compression mode should be started first. The UE performs inter-frequency or inter-system measurement. The measurements will be reported only when the conditions for

triggering inter-frequency handover or inter-system handover events are met. Thus there is a large time delay. In general, the time required to complete inter -frequency hard



handover is about 1.4 to 2 seconds and the time for inter-system handover is about 1.4 seconds, even if handover event reporting is triggered immediately after the UE activates the compression mode. Because the event reporting time of the UE is not

certain, usually inter-frequency hard handover and inter-system handover are not recommended in high-speed scenarios.

According to the previous analysis, handover needs to be optimized in the following

aspects to meet the application requirements in special scenarios of high-speed railway:

Plan the cell radius as large as possible in high-speed scenarios: When the

coverage radius of a cell is large enough, handover does not frequently occur even

if the UE moves at high speed.

Plan the handover zone as large as possible: This ensures that UEs are kept in

macro diversity state as much as possible.

Apply handover policies: Implement co-frequency coverage as much as possible for

the network layer used to absorb the traffic of high -speed UEs, so that only intra-

frequency soft handover but neither inter-frequency hard handover nor inter-system

handover is performed for high-speed UEs.

Optimize the configuration of handover parameters: Ensure that decision-making is

quick enough for measurement events which are timely notified to the network.

3.8.6 Cell Reselection Optimization

1 Shortening the time for reading system messages

In WCDMA systems, the useful system information include SIB1, SIB3, and SIB11. These system messages would be much longer if too many neighboring cells are configured. Therefore, valid neighboring cells should be configured during setting

the cell reselection parameters. Besides, cell reselection and cell handover need to be configured separately to ensure that the neighboring cell configuration would not be lost during handover.

Because the system messages are read on wireless channels which will be interfered by the surrounding wireless environment, it is ve ry hard to read the complete system messages of a cell accurately in a petition period. Instead, it takes

multiple repetition periods to finish reading all these system messages. A UE can continue to camp on a cell only after reading all the system messages of this cell. Therefore, to ensure that UEs can quickly camp on a cell, the network needs to

shorten the repetition period of the system messages as much as possible.

2 Configuring reselection parameters

Reselection parameters should be reasonably configured to quicken the cell

reselection procedure. Because UEs may move very fast, to timely respond to QoS changes, you can set the SIntraSearchPre parameter to No (indicating that the SIB message does not carry the relevant SIntraSearch information), so that the UE

periodically performs intra-frequency measurement. The TReselection parameter is used to avoid misjudgment due to burst signals. In general, UEs move unidirectional and the signal quality does not fluctuate much in high-speed scenarios. Therefore,



this parameter should be set to a value as small as possible to quicken the cell reselection procedure. Furthermore, parameters QHyst2S/QHyst1S and Qoffset1SNSib11/Qoffset2SNSib11 can also be set to small values. Cell reselection

is performed as long as the signal quality of the neighboring cells is slightly better than the signal quality of the current cell.

4 Parameters Related to Coverage Enhancement Control

4.1 Parameters Related to RF Connection

4.1.1 Parameter List

Abbreviated name Parameter name

Rack Configuration Table

RackNo Rack No

RackType Rack Type

Rack Topology Configuration Table

RackNo RACKNO

ShelfNo SHELFNO

SlotNo SLOTNO

PortID PORT

ChildRackNo RACKNO

ChildShelfNo SHELFNO

ChildSlotNo SLOTNO

ChildPort ID PORT

TopologyType Topo type

RF Connection Table

RackNo RACKNO

ShelfNo SHELFNO

SlotNo SLOTNO

Rx port ID Rx port ID

Parent frequency

band Parent frequency band

Sub frequency

band Sub frequency band



4.1.2 Parameter Configuration

4.1.2.1 Rack No

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE-

>Base Station Config Set->Equipment object->Rack ->Rack No

Parameter Configuration

The parameter indicates the rack number.

4.1.2.2 Rack Type

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->Equipment object->Rack ->Rack Type


The parameter indicates the rack type.

When the rack number is 1, you can only select the main rack that matches the BTS type, and you cannot modify this rack type. When the rack number is large r than 1, you

can select a RRU rack (ZXSDR R8840, ZXSDR R8860, ZXSDR R8880).

4.1.2.3 RACKNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of

previous hop in topology structure->RACKNO


The parameter indicates the number of the upper-level rack in the topology. Its value is

equal to the number of a configured rack that serves as an upper-level rack.

4.1.2.4 SHELFNO

OMC Path


>Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of previous hop in topology structure->SHELFNO




The parameter indicates the number of the shelf accommodating the upper-level board in the topology. Its value is automatically specified.

4.1.2.5 SLOTNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of previous hop in topology structure->SLOTNO


The parameter indicates the number of the slot accommodating the upper-level board in the topology. Its value is automatically specified.

4.1.2.6 PORT

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of

previous hop in topology structure->PORT


The parameter indicates the number of the available port of the upper -level board. The

value range is automatically adjusted according to the selected upper-level board.

4.1.2.7 RACKNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of next

hop in topology structure->RACKNO


The parameter indicates the number of the lower-level rack in the topology. Its value is

equal to the number of a configured rack that serves as a lower-level rack.

4.1.2.8 SHELFNO

OMC Path



View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of next hop in topology structure->SHELFNO


The parameter indicates the number of the shelf accommodating the lower-level board in the topology. Its value is automatically specified according to the selected board.

4.1.2.9 SLOTNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of next hop in topology structure->SLOTNO


The parameter indicates the number of the slot accommodating the lower -level board in the topology. Its value is automatically specified according to the selected b oard.

4.1.2.10 PORT

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Fiber cable object ->Optical port of next

hop in topology structure->PORT


The parameter indicates the number of the available port of the lower-level board in the

topology. At present, its value can only be equal to 0.

4.1.2.11 RACKNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Rx device object ->RACKNO


The parameter indicates the number of the RF rack. The parameter is automatically configured when RF board is configured.



4.1.2.12 SHELFNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Rx device object ->SHELFNO


The parameter indicates the number of the RF shelf. The parameter is automatically configured when RF board is configured.

4.1.2.13 SLOTNO

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Rx device object ->SLOTNO


The parameter indicates the number of the slot accommodating the RF board. The parameter is automatically configured when RF board is configured.

4.1.2.14 Rx port ID

OMC Path


>Base Station Config Set-> Equipment object->Rx device object ->Rx port ID


The parameter indicates the RF port ID. Its value can be equal to 0 or 1. The parameter

is automatically configured when RF board is configured

4.1.2.15 Parent frequency band

OMC Path


>Base Station Config Set-> Equipment object->Rx device object ->Parent frequency band


The parameter indicates the band flag. The parameter is automatically configured when

RF board is configured



4.1.2.16 Sub frequency band

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set-> Equipment object->Rx device object ->Sub frequency band


The parameter indicates the sub band flag. The parameter is automatically configured when RF board is configured

4.2 Parameters Related to Receive Diversity



Tx Type Tx Type

Tx device Tx device

Rx Type Rx Type

Rx device Rx device


4.2.2.1 Tx Type

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Tx Type


The parameter indicates the type of transmit diversity.

4.2.2.2 Tx device

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Tx device


The parameter indicates the transmitting antenna of the RRU. The antennas of several RRU can be selected.



4.2.2.3 Rx Type

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Rx Type


The parameter is used to configure the receiving type of the antenna.

4.2.2.4 Rx device

OMC Path


>Base Station Config Set->SdrFunction object->UMTS sector object-> Rx device


The parameter indicates the receiving antenna of the RRU. The receiving antennas of

several RRU can be selected.

4.3 Parameters Related to Multi-RRU One Cell

4.3.1 Parameter List Refer to 4.2.1 Parameter list


Refer to 4.2.2 Parameter Configuration

4.4 Parameters Related to Transmit Diversity



Tx Type Tx Type

Tx device Tx device

Rx Type Rx Type

Rx device Rx device

TxDivMod Transmit Diversity Mode

SCH.TstdInd SCH TSTD Indicator



P-CPICH.SttdInd P-CPICH STTD Indicator

S-CPICH.SttdInd S-CPICH STTD Indicator

P-CCPCH.SttdInd PCCPCH STTD Indicator

S-CCPCH.SttdInd SCCPCH STTD Indicator

MICH.SttdInd MICH STTD Indicator

AICH.SttdInd AICH STTD Indicator

PICH.SttdInd PICH STTD Indicator

TxDivInd Tx Diversity Indicator


4.4.2.1 Tx Type

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Tx Type


The parameter indicates the type of transmit diversity.

4.4.2.2 Tx device

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Tx device


The parameter indicates the transmitting antenna of the RRU. The antennas of several RRU can be selected.

4.4.2.3 Rx Type

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Rx Type


The parameter is used to configure the receiving type of the antenna.



4.4.2.4 Rx device

OMC Path

View->Configuration Management->OMC->UTRAN SubNetwork->Management NE->Base Station Config Set->SdrFunction object->UMTS sector object-> Rx device


The parameter indicates the receiving antenna of the RRU. The receiving antennas of several RRU can be selected.

4.4.2.5 Transmit Diversity Mode

OMC Path

Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC Management Element -> RNC Config Set -> RNC Radio Resource Management ->

Advanced Parameter Manager -> Power Control Related to Service and Diversity Mode -> Sub-service Type XXX -> Transmit Diversity Mode


This parameter indicates the mode of transmit diversity.

4.4.2.6 SCH TSTD Indicator

OMC Path


Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> PSCH -> SCH TSTD Indicator


The parameter is used if it is necessary to improve the receiving performance of the mobile UE. When the parameter is activated, the SCH receiving performance of the UE is improved. In case any downlink channel uses transmit diversity, the SCH must also

use transmit diversity.

4.4.2.7 P-CPICH STTD Indicator

OMC Path

View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC

Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> PCPICH -> P-CPICH STTD Indicator




When the parameter is activated, the transmit diversity of the PCPICH is enabled.

4.4.2.8 S-CPICH STTD Indicator

OMC Path

Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC

Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> SCPICH -> S-CPICH STTD Indicator


When the parameter is activated, the transmit diversity of the P-CCPCH is enabled.

4.4.2.9 PCCPCH STTD Indicator

OMC Path

Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> PCCPCH -> PCCPCH

STTD Indicator


The parameter is used if it is necessary to improve the receiving performance of the

mobile UE. When the parameter is activated, the P-CCPCH receiving performance of the UE is improved. In case any downlink channel uses transmit diversity, the P-CCPCH must also use transmit diversity.

4.4.2.10 S-CCPCH STTD Indicator

OMC Path

Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> S-CCPCH ->

SCCPCH STTD Indicator


When the parameter is activated, the transmit diversity of the S-CCPCH is enabled.

4.4.2.11 MICH STTD Indicator

OMC Path



Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> MICH -> MICH STTD

Indicator


When the parameter is activated, the transmit diversity of the MICH is enabled.

4.4.2.12 AICH STTD Indicator

OMC Path

Path: View -> Configuration Management -> OMC -> UTRAN SubNetwork -> RNC Management Element -> RNC Config Set -> RNC Radio Resource Management -> Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> AICH -> AICH STTD

Indicator


When the parameter is activated, the transmit diversity of the AICH is enabled.

4.4.2.13 PICH STTD Indicator

OMC Path


Utran Cell -> Utran Cell XXX -> Advanced Parameter Manager -> PICH -> PICH STTD Indicator


When the parameter is activated, the transmit diversity of the PICH is enabled.

4.5 Parameter Related to Extended Cell Range to 80Km

4.5.1 Pa

zte umts coverage enhancement feature guide u9.2

Documents

zte corporation

proprietary information

diversity mode

improvement of zte products

coverage enhancement

extended cell range

optimization of antenna

single antenna reception