123325177 Huawei BTS 3900 Technical Description

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3900 Series GSM Base Station

V100R013C00

Technical Description

Issue 12

Date 2012-12-30

HUAWEI TECHNOLOGIES CO., LTD.


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Copyright Huawei Technologies Co., Ltd. 2012. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior written

consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.

All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice

The purchased products, services and features are stipulated by the contract made between Huawei and the

customer. All or part of the products, services and features described in this document may not be within the

purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representations

of any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in the

preparation of this document to ensure accuracy of the contents, but all statements, information, and

recommendations in this document do not constitute a warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base

Bantian, Longgang

Shenzhen 518129

People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

Issue 12 (2012-12-30) Huawei Proprietary and Confidential

Copyright Huawei Technologies Co., Ltd.

i
http://www.huawei.com/


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About This Document

Overview

This document provides information about 3900 series GSM base stations such as system

principles, operation and maintenance, clock synchronization schemes, and surge protection

specifications, aiming to enable operators to comprehensively understand functions of the 3900

series GSM base stations.

Product Version

The following table lists product versions involved in this document.

Product Name Product Version

BTS3900 GSM (BTS3900 for short) V100R013C00

BTS3900A GSM (BTS3900A for short) V100R013C00

BTS3900L GSM (BTS3900L for short) V100R013C00

DBS3900 GSM (DBS3900 for short) V100R013C00

Intended AudienceThis document is intended for:

l Network planners

l Field engineers

l System engineers

Organization

1 Changes in the 3900 Series GSM Base Station Technical Description


Technical Description About This Document



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This section describes changes in the 3900 Series GSM Base Station Technical Description of

each version.

2 Overview

3900 series base stations adopt the cutting-edge modular design for different modes and aremanaged by various systems. With simple components, they can be installed and deployed easily

and fast. With comprehensive functions and remarkable performance, they can meet

requirements in various scenarios. In addition, they are diversified by flexibly combining

functional modules and auxiliary devices.

3 BTS System Principle

The BTS consists of the BBU3900 (BBU for short), RF modules, and the antenna system. Its

functional subsystem includes the control system, transport system, monitoring system, RF

system, antenna system, and power supply system.

4 Control and Transport Systems

The functions of the control and transport systems are provided by the BBU. The control system

manages the entire BTS system in a centralized manner, including signaling processing,

operation and maintenance, and system clock. The transport system provides physical ports

connecting the BTS and the transport network.

5 RF System

The functions of the RF system are provided by RF modules including the radio frequency units

(RFUs) that are used in macro base stations and remote radio units (RRUs) that are used in

distributed base stations. The RF system performs modulation, demodulation, data processing,

and combination and division of RF and baseband signals.

6 Antenna System

The antenna system consists of antennas, feeders, jumpers, the Tower Mounted Amplifier

(TMA), the Bias Tee (BT), and the GSM Antenna and TMA Control Module (GATM). It

transmits and receives RF signals.

7 Operation and Maintenance

Operation and Maintenance (OM) covers management, monitoring, and maintenance of the

software, hardware, and configuration of the BTSs. In addition, diversified OM modes are

provided in various scenarios.

8 External Reference Clock Sources

The BTS supports multiple external reference clock sources, including the IP reference clock,

E1/T1 reference clock, synchronous Ethernet reference clock, BITS reference clock, and GPS/

RGPS reference clock. If a BTS fails to obtain clock signals, it works in free-run mode for a

certain period of time.

9 Surge Protection Specifications

This section provides surge protection specifications for the BBU, RF modules, and each type

of base stations.

10 Technical Specifications

This section provides technical specifications for RF modules.





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Conventions

Symbol Conventions

The symbols that may be found in this document are defined as follows.

Symbol Description

Indicates a hazard with a high level or medium level of risk

which, if not avoided, could result in death or serious injury.

Indicates a hazard with a low level of risk which, if not

avoided, could result in minor or moderate injury.

Indicates a potentially hazardous situation that, if not

avoided, could result in equipment damage, data loss,

performance deterioration, or unanticipated results.

Indicates a tip that may help you solve a problem or save

time.

Provides additional information to emphasize or supplement

important points of the main text.

General Conventions

The general conventions that may be found in this document are defined as follows.

Convention Description

Times New Roman Normal paragraphs are in Times New Roman.

Boldface Names of files, directories, folders, and users are in

boldface. For example, log in as userroot.

Italic Book titles are in italics.

Courier New Examples of information displayed on the screen are in

Courier New.

Command Conventions

The command conventions that may be found in this document are defined as follows.


Boldface The keywords of a command line are in boldface.

Italic Command arguments are in italics.

[ ] Items (keywords or arguments) in brackets [ ] are optional.





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{ x | y | ... } Optional items are grouped in braces and separated by

vertical bars. One item is selected.

[ x | y | ... ] Optional items are grouped in brackets and separated byvertical bars. One item is selected or no item is selected.

{ x | y | ... }* Optional items are grouped in braces and separated by

vertical bars. A minimum of one item or a maximum of all

items can be selected.

[ x | y | ... ]* Optional items are grouped in brackets and separated by

vertical bars. Several items or no item can be selected.

GUI Conventions

The GUI conventions that may be found in this document are defined as follows.


Boldface Buttons, menus, parameters, tabs, window, and dialog titles

are in boldface. For example, clickOK.

> Multi-level menus are in boldface and separated by the ">"

signs. For example, choose File > Create > Folder.

Keyboard Operations

The keyboard operations that may be found in this document are defined as follows.

Format Description

Key Press the key. For example, press Enter and press Tab.

Key 1+Key 2 Press the keys concurrently. For example, pressing Ctrl+Alt

+A means the three keys should be pressed concurrently.

Key 1, Key 2 Press the keys in turn. For example, pressing Alt, A meansthe two keys should be pressed in turn.

Mouse Operations

The mouse operations that may be found in this document are defined as follows.

Action Description

Click Select and release the primary mouse button without moving

the pointer.





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Action Description

Double-click Press the primary mouse button twice continuously and

quickly without moving the pointer.

Drag Press and hold the primary mouse button and move thepointer to a certain position.





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Contents

About This Document.....................................................................................................................ii

1 Changes in the 3900 Series GSM Base Station Technical Description...............................1

2 Overview.........................................................................................................................................8

3 BTS System Principle.................................................................................................................13

4 Control and Transport Systems................................................................................................15

4.1 Logical Structure of the BBU...........................................................................................................................16

4.2 BBU Transmission Ports..................................................................................................................................17

4.3 Transport Network Topologies.........................................................................................................................18

5 RF System......................................................................................................................................24

5.1 Logical Structure of the RRU...........................................................................................................................26

5.2 Logical Structure of the RFU...........................................................................................................................30

5.3 CPRI-Based Topologies...................................................................................................................................32

5.4 RRU3004 Configuration...................................................................................................................................36

5.5 Configurations of RRU3008, RRU3908, RRU3928, RRU3929, RRU3942, RRU3926, and the MRFUd

................................................................................................................................................................................42

5.6 DRFU Configuration........................................................................................................................................49

5.7 Configurations of the GRFU/MRFU/MRFUe..................................................................................................58

5.8 Hybrid Configuration of RF Modules..............................................................................................................64

6 Antenna System...........................................................................................................................68

7 Operation and Maintenance......................................................................................................70

7.1 OM Modes of the BTS.....................................................................................................................................71

7.2 OM Functions of the BTS................................................................................................................................71

8 External Reference Clock Sources............................................................................................74

9 Surge Protection Specifications................................................................................................76

10 Technical Specifications...........................................................................................................84

10.1 Technical Specifications for RFUs.................................................................................................................85

10.1.1 DRFU Technical Specifications............................................................................................................85

10.1.2 GRFU Technical Specifications............................................................................................................88

10.1.3 Technical Specifications for MRFU......................................................................................................94


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10.1.4 Technical Specifications for MRFUd..................................................................................................108

10.1.5 Technical Specifications for MRFUe..................................................................................................122

10.2 Technical Specifications for RRUs..............................................................................................................130

10.2.1 RRU3004 Technical Specifications.....................................................................................................130

10.2.2 RRU3008 Technical Specifications.....................................................................................................136

10.2.3 Technical Specifications for RRU3908...............................................................................................145






Technical Description Contents



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1Changes in the 3900 Series GSM Base StationTechnical Description

This section describes changes in the 3900 Series GSM Base Station Technical Description of

each version.

12 (2012-12-30)

This is issue 12.

Compared with issue 11 (2012-10-20), this issue not include any new topics.

Compared with issue 11 (2012-10-20), this issue incorporates the following changes:

Topic Description

10.1 Technical Specifications for RFUs Added the maximum output power supported

by the RF modules.

10.1.2 GRFU Technical Specifications Modified power consumption of the GRFU.

10.2 Technical Specifications for RRUs Added the maximum output power supported

by the RF modules.

Compared with issue 11 (2012-10-20), this issue does not exclude any topics.

11 (2012-10-20)

This is issue 11.



Topic Description

5.8 Hybrid Configuration of RF Modules Modified the content for RFUs.



1 Changes in the 3900 Series GSM Base Station Technical

Description



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Topic Description

10.1 Technical Specifications for RFUs Modified the RET antenna support capability

of each type of RFUs and specified whether

each of them complies with AISG1.1.

10.2 Technical Specifications for RRUs Modified the RET antenna support capability

of each type of RRUs and specified whether

each of them complies with AISG1.1.


10 (2012-09-27)

This is issue 10.

Compared with issue 09 (2012-06-30), this issue includes the following new topic:

l 5.8 Hybrid Configuration of RF Modules


Topic Description

9 Surge Protection Specifications Added the surge protection specifications for

the BTS3900(Ver.D), BTS3900L(Ver.D)

and BTS3900A(Ver.D) cabinet.

5.7 Configurations of the GRFU/MRFU/

MRFUe

Removed MRFU V3 modules.


09 (2012-06-30)

This is issue 09.



Topic Description

5.5 Configurations of RRU3008,

RRU3908, RRU3928, RRU3929,

RRU3942, RRU3926, and the MRFUd

Modified the number of carriers supported by

the RRU3908 V1.

4.3 Transport Network Topologies Added the networking with IP over E1/T1.

10.2 Technical Specifications for RRUs Modified the operating environment

standards for RRUs.




Description



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Topic Description

10.1.5 Technical Specifications for

MRFUe

Added specifications when it operates in the

900 MHz frequency band.


08 (2012-05-20)

This is issue 08.



Topic Description

7.2 OM Functions of the BTS Added the note: The security of the USB

loading port is ensured by encryption.


07 (2012-03-30)

This is issue 07.


l 10.2.7 Technical Specifications for RRU3926


Topic Description


RRU3908, RRU3928, RRU3929,


Added the Configurations on an RRU3926.

5.3 CPRI-Based Topologies Added the specifications of CPRI ports on an

RRU3926.


06 (2012-02-25)

This is issue 06.





Description



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l 10.2.6 Technical Specifications for RRU3942


Topic Description


RRU3908, RRU3928, RRU3929,


Added the Configurations on an RRU3942.

5.3 CPRI-Based Topologies Added the specifications of CPRI ports on an

RRU3942.

10.1.1 DRFU Technical Specifications Updated surge protection specifications.

10.1.2 GRFU Technical Specifications Updated surge protection specifications.

10.1.3 Technical Specifications for MRFU Updated RF specifications.


MRFUd

Updated RF specifications.


MRFUe


10.2.1 RRU3004 Technical Specifications Added the standards with which an RRU3004

complies

10.2.2 RRU3008 Technical Specifications Added the standards with which an RRU3008

complies

10.2.3 Technical Specifications forRRU3908



RRU3928



RRU3929



05 (2011-11-30)

This is issue 05.



Topic Description

10 Technical Specifications Technical specifications has been updated.




Description



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04 (2011-09-30)

This is issue 04.


l 10.1 Technical Specifications for RFUs

l 10.2 Technical Specifications for RRUs


Topic Description

9 Surge Protection Specifications Surge protection specifications for the ports

on RF modules has been deleted.


03 (2011-08-30)

This is issue 03.

Compared with issue 02 (2011-06-25), this issue does not include any new topics.


Topic Description

9 Surge Protection Specifications VER.B of the cabinet is added.


02 (2011-06-25)

This is issue 02.


l 5.5 Configurations of RRU3008, RRU3908, RRU3928, RRU3929, RRU3942,

RRU3926, and the MRFUd

l 5.7 Configurations of the GRFU/MRFU/MRFUe


Topic Description

5.1 Logical Structure of the RRU Information about the RRU3929 is added.

5.2 Logical Structure of the RFU Information about the MRFUe is added.




Description



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Topic Description

5.3 CPRI-Based Topologies Information about the RRU3929, MRFUe is

added.

9 Surge Protection Specifications Surge protection specifications for the portson the RRU3929, MRFUe are added.

Compared with issue 01 (2011-04-30), this issue excludes the following topic:

l Configurations of RRU3008, RRU3908, RRU3928, GRFU, MRFU, and the MRFUd

01 (2011-04-30)

This is issue 01.

Compared with issue 07 (2011-03-30) of V100R012, this issue includes the following new

topics:

l 2 Overview

l 3 BTS System Principle

l 4.2 BBU Transmission Ports

l 5.2 Logical Structure of the RFU

l 5.7 Configurations of the GRFU/MRFU/MRFUe

l 6 Antenna System

l 7 Operation and Maintenance

Compared with issue 07 (2011-03-30) of V100R012, this issue incorporates the following

changes:

Topic Description

5.1 Logical Structure of the RRU Information about the RRU3908 and

RRU3928 is added.

5.3 CPRI-Based Topologies Information about the MRFU, MRFUd,

RRU3908, and RRU3928 is added.

9 Surge Protection Specifications Surge protection specifications for the portson the BTS3900 (Ver.C), BTS3900L

(Ver.C), BTS3900A (Ver.C), MRFU,

MRFUd, RRU3908, and RRU3928 are

added.

Compared with issue 07 (2011-03-30) of V100R012, this issue excludes the following topics:

l DBS3900 Product Family

l System Architecture of the BTS3900

l System Architecture of the BTS3900A




Description



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l System Architecture of the BTS3900L

l Software Structure of the BTS

l Logical Structure of the BTS3900

l Logical Structure of the BTS3900L

l Logical Structure of the BTS3900A

l DBS3900 Monitoring Schemes

l BTS3900 Monitoring System

l BTS3900A Monitoring System

l BTS3900L Monitoring System

l Signal Flow of the BTS3900/BTS3900A

l Signal Flow of the BTS3900L

l Configuration of the BTS3900/BTS3900A

l Configuration of the BTS3900L

l CPRI Cable Connections of the RRUs

l RRU3008 Configuration

l Typical Scenarios of the DBS3900 (with the DC RRU)

l Typical Scenarios of the DBS3900 (with the AC RRU)




Description



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2 Overview3900 series base stations adopt the cutting-edge modular design for different modes and are

managed by various systems. With simple components, they can be installed and deployed easily

and fast. With comprehensive functions and remarkable performance, they can meet

requirements in various scenarios. In addition, they are diversified by flexibly combining

functional modules and auxiliary devices.

BTS in the BSS

The base station subsystem (BSS) mainly consists of the base station controller (BSC) and the

base transceiver station (BTS), as shown in Figure 2-1.


Technical Description 2 Overview



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Figure 2-1 BSS architecture

BTS Types

There are four types of BTSs, that is, BTS3900, BTS3900A, BTS3900L, and DBS3900, meeting

requirements in various scenarios, as shown in Table 2-1.





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Table 2-1 BTS types

Name

Type Usage Scenario InputPower

CabinetCombination

Reference

BTS3900

Indoor

macro

base

statio

n

Indoor installationscenarios where

traffic load is

heavy, lease cost of

equipment room is

high, or equipment

room is space-

limited.

l -48 VDC

l +24 V

DC

l 220 V

AC

l 110 V

AC

l Single cabinetl Double

cabinets: Two

cabinets are

installed side

by side or two

cabinets are

stacked.

For informationabout usage

scenarios and

configurations of

cabinets, see

BTS3900(Ver.B)

Hardware

Description,

BTS3900(Ver.C)

Hardware

Description and

BTS3900(Ver.D)

HardwareDescription.

BTS

3900

A

Outdo

or

macro

base

statio

n

Outdoor

installation

scenarios where

wide coverage is

required such as

cities, suburbs, or

rural areas.

l -48 V

DC

l 220 V

AC

l 110 V

AC

l TMC11H +

RFC

l APM30H +

RFC (+IBBS

+ TMC11H)

APM30H is a

power cabinet,

the RFC is a radio

frequency

cabinet,

TMC11H is a

transmission

cabinet, and the

IBBS is a battery

cabinet. Forinformation

about usage

scenarios and

configurations of

cabinets, see

BTS3900A

(Ver.B)

Hardware

Description,

BTS3900A

(Ver.C)

HardwareDescription and

BTS3900A

(Ver.D)

Hardware

Description.





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Name


CabinetCombination

Reference

BTS

3900

L

Indoo

r

macro

base

statio

n

Indoor installation

scenarios with

large capacity

where traffic load

is heavy, lease cost

of equipment room

is high, or

equipment room is

space-limited.

-48 V DC Single cabinet For information

about usage

scenarios and

configurations of

cabinets, see

BTS3900L

(Ver.B)

Hardware

Description,

BTS3900L

(Ver.C)

Hardware

Description and

BTS3900L(Ver.D)

Hardware

Description.





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Name


CabinetCombination

Reference

DBS

3900

Distri

buted

base

statio

n

Outdoor

installation

scenarios where

site deployment is

difficult and wide

coverage is

required.

l -48 V

DC

l +24 V

DC

l 220 V

AC

l BBU +

APM30H +

RRU

l BBU +

TMC11H +

RRU

l BBU + 19-

inch rack +

RRU

l Indoor wall-

mounted BBU

+ RRU

l BBU + OMB+ RRU

l BBU + ICR +

RRU

l BBU + IMB03

+ RRU

APM30H is a

power cabinet,

TMC11H is a

transmission

cabinet, the

OMB is an

outdoor mini

box, the ICR is an

indoor

centralized rack,

and IMB03 is an

indoor mini box.

For information

about usagescenarios and

configurations of

cabinets, see

BBU3900

Hardware

Description,

APM30H&TMC

11H&IBBS200D

&IBBS200T

(Ver.B) Product

Description,

APM30H&TMC11H&IBBS200D

&IBBS200T

(Ver.C) Product

Description,

APM30H&TMC

11H&IBBS200D

&IBBS200T

(Ver.D) Product

Description and

RRUxxxx

Hardware

Description.

NOTERRUxxxx refers

to the model of

each RRU.





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3 BTS System PrincipleThe BTS consists of the BBU3900 (BBU for short), RF modules, and the antenna system. Its

functional subsystem includes the control system, transport system, monitoring system, RF

system, antenna system, and power supply system.

Figure 3-1 shows the BTS system principle.

Figure 3-1 BTS system principle

Functions of each system are as follows:

l Control system: Managing the entire BTS system in a centralized manner, including

operation and maintenance, signaling processing, and system clock. For details, see section

4 Control and Transport Systems.

l

Transport system: Providing physical ports connecting the BTS and the transport networkand also provides maintenance channels connecting the BTS and the Operation and


Technical Description 3 BTS System Principle



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Maintenance Center (OMC) to enable information exchange between the BTS and the

transport network or OMC. For details, see section 4 Control and Transport Systems.

l Monitoring system: Collecting external alarm information and reporting the information

to the control system. For details, see chapterMonitoring System in theHardware

Description of the corresponding base station type.l RF system: Processing RF and baseband signals. For details, see section 5 RF System.

l Antenna system: Receiving uplink signals and transmitting downlink signals. For details,

see section 6 Antenna System.

l Power supply system: Obtaining power from external power supply devices and providing

power for other subsystems of the BTS. For details, see chapterPower System in the

Hardware Description of the corresponding base station type.


Technical Description 3 BTS System Principle



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4 Control and Transport SystemsAbout This Chapter

The functions of the control and transport systems are provided by the BBU. The control system

manages the entire BTS system in a centralized manner, including signaling processing,

operation and maintenance, and system clock. The transport system provides physical ports

connecting the BTS and the transport network.

4.1 Logical Structure of the BBU

The BBU consists of the main processing unit, BTS interface unit, high-speed interface unit,

clock unit, and monitoring unit.

4.2 BBU Transmission PortsThe GTMU or UTRP board provides transmission ports to enable information exchange between

the BTS and the transport network.

4.3 Transport Network Topologies

Transport network topologies include TDM, IP, and High level Data Link Control (HDLC)

network topologies. In reality, these topologies are combined to save transmission device costs

without deteriorating service quality.


Technical Description 4 Control and Transport Systems



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4.1 Logical Structure of the BBU

The BBU consists of the main processing unit, BTS interface unit, high-speed interface unit,

clock unit, and monitoring unit.

Figure 4-1 shows the logical structure of the BBU.

Figure 4-1 Logical structure of the BBU

The control system consists of the main processing unit while the transport system consists of

the BTS interface unit and high-speed interface unit.

Main Processing Unit

The main processing unit manages the entire BTS system in a centralized manner, including

operation and maintenance, signaling processing, and system clock. It provides the following

functions:

l Supports such protocols as UART, HDLC, and IP over FE.

l Controls the BTS interface unit to enable communication between the BBU and the BSC.

l Controls the High-speed interface unit to enable communication between the BBU and RF

modules.

l Provides system clock for the BTS and obtains external clock signals.

BTS Interface Unit

The BTS interface unit enables information exchange between the BTS and the transport network

by providing the following functions:

l Connects the BTS with the BSC.

l Exchanges data between the E1 link and the DBUS.





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l Synchronizes an upper-level clock with a lower-level clock.

High-Speed Interface Unit

The high-speed interface unit enables information exchange between the BBU and RF modulesby providing the following functions:

l Receives the uplink baseband data from RF modules.

l Transmits the downlink baseband data to RF modules.

Clock Unit

The clock unit provides the following functions:

l Provides system clock stemmed from high-precision clock sources for the BTS.

l Checks the phase-locked status, provides phase lock for the software, adjusts DA, andgenerates frame numbers.

Monitoring Unit

The monitoring unit collects external alarms and reports the alarms to the central processing

unit.

4.2 BBU Transmission Ports

The GTMU or UTRP board provides transmission ports to enable information exchange between

the BTS and the transport network.

Table 4-1 provides the specifications of transmission ports on the GTMU and UTRP boards.

Table 4-1 Specifications of transmission ports on the GTMU and UTRP boards

TransmissionMode

Board Port Capacity

TDM over E1/T1 GTMU/GTMUb 1 4 ports

UTRPb4 1 4 ports

IP over E1/T1 GTMU/GTMUb 1 4 ports

Transmission over

FE optical ports

GTMU/GTMUb 1 10 Mbit/s or 100

Mbit/s

Transmission over

FE electrical ports

GTMU/GTMUb 1 10 Mbit/s or 100

Mbit/s

NOTE

The GTMU or GTMUb board is a mandatory board while the UTRPb4 board must be configured only whenmore than four E1s/T1s are required.





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4.3 Transport Network Topologies

Transport network topologies include TDM, IP, and High level Data Link Control (HDLC)

network topologies. In reality, these topologies are combined to save transmission device costs

without deteriorating service quality.

TDM Network Topology

E1/T1 transmission is adopted for communication between the BTS and the BSC while TDM

transmission is adopted on the Abis interface. TDM network topology includes such network

topologies as chain, star, tree, and ring, as shown in Figure 4-2.





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Figure 4-2 TDM network topology

Table 4-2 describes usage scenarios and advantages of the preceding four topologies.





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Table 4-2 Usage scenarios and advantages of the four topologies

Topology Usage Scenario Advantage

Star A wild range of areas,

especially densely populatedareas

l Networking is simple.

l Engineering is easy.

l Maintenance is easy.

l Network capacity expansion is easy.

l Transmission reliability is high.

Chain Strip areas that are sparsely

populated such as areas along

highways and railways

This topology helps reduce expenditure

on transmission device, engineering,

and leased transmission cables.

Tree Areas where network

architecture, site distribution,

and subscriber distributionare complicated such as an

area where large-scale

coverage overlaps with hot

spot areas or small-scale

coverage.

Compared with the star topology, this

topology requires fewer transmission

cables.

Ring A wild range of areas.

Because of its self-healing

capability, this topology is

recommended when a route is

available.

A ring topology can automatically split

into two chains if transmission is

disrupted at a breakpoint and base

stations before and after the breakpoint

can still function properly. This

improves the system robustness. Asshown in Figure 4-3, transmission is

disrupted at B. Before disruption, BTSs

0, 1, and 2 are connected in a clockwise

direction, forming a ring topology. After

disruption, transmission is normal at

BTS 0 and BTSs 1 and 2 form a chain

topology with BTS 2 being the upper-

level base station.

Figure 4-3 Re-established topology after transmission is disrupted on a ring topology





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IP Network Topology

The Abis interface between the GBTS and BSC uses the IP over FE or IP over E1/T1 transmission

mode. IP network topology includes IP over FE and IP over E1/T1 networking.

IP over FE network topology includes layer-2 and layer-3 networking, as shown in Figure

4-4.

Figure 4-4 IP over FE network topology

IP over E1/T1 network topology includes start, chain, and tree networking, as shown in Figure

4-5.





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Figure 4-5 IP over E1/T1 network topology

HDLC Network Topology

E1/T1 transmission is adopted for communication between the BTS and the BSC while HDLC

transmission is adopted on the Abis interface. HDLC network topology includes such network

topologies as chain, star, and ring, as shown in Figure 4-6.





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Figure 4-6 HDLC network topology





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5 RF SystemAbout This Chapter

The functions of the RF system are provided by RF modules including the radio frequency units

(RFUs) that are used in macro base stations and remote radio units (RRUs) that are used in

distributed base stations. The RF system performs modulation, demodulation, data processing,

and combination and division of RF and baseband signals.

5.1 Logical Structure of the RRU

RRUs include RRU3004, RRU3008, RRU3908, RRU3928, RRU3929, RRU3942 and

RRU3926.

5.2 Logical Structure of the RFUThe RFU includes the DRFU, GRFU, MRFU V1, MRFU V2, MRFUd and MRFUe.

5.3 CPRI-Based Topologies

Multiple CPRI-based topologies such as chain, star, and ring are supported for communication

between BBUs and radio frequency (RF) modules.

5.4 RRU3004 Configuration

RRU3004 is a double-transceiver remote radio unit and supports two carriers. Different

configurations must be chosen in different topologies.

5.5 Configurations of RRU3008, RRU3908, RRU3928, RRU3929, RRU3942, RRU3926, and

the MRFUd

RRU3008, RRU3908, RRU3928, RRU3929, RRU3942, and RRU3926 are multi-carrier remoteradio units. An RRU3908 V1 supports a maximum of six carriers. RRU3908 V2 and other

modules support a maximum of eight carriers each. MRFUd is a multi-carrier radio frequency

(RF) module and supports a maximum of eight carriers. RF configuration modes need to be

selected depending on networking configurations.

5.6 DRFU Configuration

The DRFU is a double-transceiver module and supports two carriers. Different configurations

must be chosen in different topologies.

5.7 Configurations of the GRFU/MRFU/MRFUe

The GRFU, MRFU V1, MRFU V2, and MRFUe are multi-carrier radio frequency (RF) modules.

A GRFU or MRFU V1 or MRFU V2 supports six carriers, and an MRFUe supports eight carriers.Different configurations must be chosen in different topologies.


Technical Description 5 RF System



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5.8 Hybrid Configuration of RF Modules

This chapter describes the cabinets supported by RFUs and RRUs and principles for hybrid

configuration.





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5.1 Logical Structure of the RRU

RRUs include RRU3004, RRU3008, RRU3908, RRU3928, RRU3929, RRU3942 and

RRU3926.

RRU3004 consists of a high-speed interface unit, signal processing unit, power amplifier (PA),

low noise amplifier (LNA), and dual duplexer. Figure 5-1 shows the logic structure of RRU3004.

Figure 5-1 Logical structure of RRU3004

RXM_OUT: It is a main receive output port and is used

for RRU interconnecting.

RXD_IN: It is a receive diversity input port and is used


RRU3008 consists of a main control and high-speed interface unit, signal processing unit, PA,

LNA, RX, and dual duplexer. Figure 5-2 shows the logic structure of RRU3008.





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Figure 5-2 Logical structure of RRU3008

RXM_OUT: It is a main receive output port and is used


RXD_IN: It is a receive diversity input port and is used


RRU3908, RRU3928, or RRU3929 consists of a high-speed interface unit, signal processing

unit, PA, LNA, and duplexer. Figure 5-3 shows the logic structures of RRU3908, RRU3928,

and RRU3929.

Figure 5-3 Logical structures of RRU3908, RRU3928, and RRU3929

RRU3942 consists of a high-speed interface unit, signal processing unit, PA, LNA, and duplexer.

Figure 5-4 shows the logic structures of RRU3942.





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Figure 5-4 Logical structures of RRU3942

RRU3926 consists of a high-speed interface unit, signal processing unit, PA, LNA, and duplexer.

Figure 5-5 shows the logic structures of RRU3926.

Figure 5-5 Logical structures of RRU3926


The high-speed interface unit mainly provides the following functions:





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l Receives data from an upper-level device, such as the BBU.

l Sends data to an upper-level device, such as the BBU.

l Transfers data transmitted from cascaded RRUs by using CPRI ports.

Main Control and High-Speed Interface Unit

The main control and high-speed interface unit mainly provides the following functions:

l Receives data from an upper-level device, such as the BBU.

l Sends data to an upper-level device, such as the BBU.

l Transfers data transmitted from cascaded RRUs by using CPRI ports.

l Initializes RRU configurations and loads RRU software.

l Collects alarms and reports board status.

l Executes configuration commands sent from the BBU and manages configurations of an

RRU's other units.l Operates and maintains RRUs.

Signal Processing Unit

The signal processing unit consists of an uplink receive channel, a downlink transmit channel,

and a control module. Moreover, it mainly processes radio frequency (RF) and GSM baseband

signals.

An uplink receive channel mainly provides the following functions:

l Converts received signals into intermediate frequency analog signals by performing down-

conversion.

l Converts intermediate frequency analog signals into digital signals by using an Analog

Digit Converter (ADC).

l Processes intermediate frequency digital signals.

l Matches filtering.

l Provides the Digital Automatic Gain Control (DAGC) function.

l Packs data.

A downlink transmit channel mainly provides the following functions:

l Separates packed signals that are transmitted from the BBU including clock signals, control

signals, and data signals. Then, transmits them to specified units.

l Combines and filters multiple routes of downlink signals.

l Converts digital signals into analog signals by using a Digit Analog Converter (DAC).

Then, performs the Inphase and Quadrature (IQ) modulation.

l Converts RF signals into signals that can be transmitted in transmit frequency bands by

performing up-conversion.

A control module mainly provides the following functions:

l Initializes RRU configurations and loads RRU software.

l Collects alarms and reports board status.

l

Executes configuration commands sent from the BBU and manages configurations of anRRU's other units.





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l Operates and maintains RRUs.

PA

A PA's major function is to amplify power of multi-carrier and low-power radio frequency (RF)signals that are sent from the signal processing unit.

LNA

The LNA performs low noise amplification on signals received by antennas.

RX

The RX's major function is to convert signals sent from the LNA into intermediate frequency

analog signals by performing down-conversion. Then, it amplifies the intermediate frequency

analog signals. Finally, it sends the signals to the ADC.

Duplexer

The duplexer and the dual duplexer mainly provide the following functions:

l Filters transmitted or received signals.

l Multiplexes transmitted and received signals on RF channels. By doing this, signals are

transmitted or received using the same antenna channel.

5.2 Logical Structure of the RFU

The RFU includes the DRFU, GRFU, MRFU V1, MRFU V2, MRFUd and MRFUe.

The RFU consists of a high-speed interface unit, signaling processing unit, power amplifier (PA),

low noise amplifier (LNA), and duplexer. Figure 5-6 shows the logical structure of the DRFU.

Figure 5-7 shows the logical structure of the MRFUd. Figure 5-8 shows the logical structures

of the GRFU, MRFU V1, MRFU V2 and MRFUe.

Figure 5-6 Logical structure of the DRFU





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Figure 5-7 Logical structure of the MRFUd

Figure 5-8 Logical structures of the GRFU, MRFU and MRFUe


The high-speed interface unit mainly provides the following functions:

l Adapts signals sent from the BBU for the signaling processing unit.

l Adapts signals sent from the signaling processing unit for the BBU.





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Signal Processing Unit

The signaling processing unit consists of two uplink receive channels and one downlink transmit

channel.

An uplink receive channel mainly provides the following functions:l Converts received high frequency analog signals into intermediate frequency analog signals

by performing down-conversion.

l Amplifies intermediate frequency analog signals and performs the Inphase and Quadrature

(IQ) modulation.

l Converts analog signals into digital signals by using an Analog Digit Converter (ADC).

l Samples digital signals.

l Matches filtering.

l Provides the Digital Automatic Gain Control (DAGC) function.

l Seals frames.

A downlink transmit channel mainly provides the following functions:

l Processes signals that are transmitted from the BBU including clock signals, control signals,

and data signals. Then, transmit them to specified units.

l Shapes and filters the downlink signals.

l Converts digital signals into analog signals by using a Digit Analog Converter (DAC).

Then, performs the Inphase and Quadrature (IQ) modulation.

l Converts radio frequency (RF) signals into signals that can be transmitted in transmit

frequency bands by performing up-conversion.

PAThe PA amplifies low-power RF signals that are sent from the signaling processing unit.

LNA

The LNA's major function is to perform low noise amplification on signals received by antennas.

Duplexer

The duplexer mainly provides the following functions:

l Multiplexes transmitted and received signals on RF channels.

l Enables signals to be transmitted or received using the same antenna channel.

l Filters transmitted or received signals.

5.3 CPRI-Based TopologiesMultiple CPRI-based topologies such as chain, star, and ring are supported for communication

between BBUs and radio frequency (RF) modules.

Topologies

Figure 5-9 shows CPRI-based topologies supported for communication between BBUs and RFmodules. The DRFU, GRFU support the chain and star topologies. The RRU3004, RRU3008,





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and RRU3926 support the chain, star, and ring topologies. The MRFU V1, MRFU V2, MRFUd,

MRFUe, RRU3908, RRU3928, RRU3929, and RRU3942 support the star topology.

Figure 5-9 CPRI-based topologies

NOTE

RXU in the preceding figure indicates an RFU or RRU.

Table 5-1 describes characteristics of the three topologies in the preceding figure.





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Table 5-1 Characteristics of the three topologies

Topology

Advantage Disadvantage Remarks

Chain The transmissionequipment cost is low.

l The number ofcascading levels in a

chain and the cascading

distance are restricted.

l Faults in an upper-level

RF module may affect

lower-level RF

modules.

l This topology isapplicable to

scenarios where

capacity is large.

l RFUs and RRUs

cannot be cascaded.

Star l Installation and

maintenance are easy.

l Transmission

reliability is high.

When an RF module or

optical cable is faulty,

only one sector is

affected.

Compared with other

topologies, this topology

requires large numbers of

optical cables.

This topology is

applicable to scenarios

where capacity is small.

Ring Transmission reliability is

guaranteed.

l The number of

cascading levels in a

chain and the cascading

distance are restricted.

l Faults in an upper-level

RRU may affect lower-level RRUs.

l Only RRUs can be

used in the ring

topology.

l The ring topology is

implemented by

adding a redundantchain to a chain

topology.

Based on the distance between a BBU and an RRU, CPRI networking is classified into short-

distance remote networking and long-distance remote networking.

l For the short-distance remote networking, the longest distance between an RRU and a BBU

on a CPRI chain does not exceed 100 m.

l For the long-distance remote networking, the longest distance between an RRU and a BBU

on a CPRI chain ranges from 100 m to 40,000 m.

Different CPRI optical cables are used in the two types of networking. For details, see chapter

CPRI Optical Cable in theBBU3900 Hardware Description.

CPRI Specifications

Table 5-2 lists the specifications of CPRI ports on the GSM Transmission, Timing, and

Management Unit for BBU (GTMU).





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Table 5-2 Specifications of CPRI ports on the GTMU board

Board Numberof CPRIPorts

Data Rate Topology Number ofSupported TRXs

GTMU 6 1.25 Gbit/s Star, chain, or ring 36

GTMUb 6 1.25/2.5

Gbit/s

Star, chain, or ring 36

Table 5-3 lists the specifications of CPRI ports on different RF modules.

Table 5-3 Specifications of CPRI ports on different RF modules

RFModules

Number ofCPRIPorts

Data Rate Topology Number ofSupportedCarriers

CascadingLevels

MaximumDistancefromtheBBU

DRFU 2 1.25 Gbit/s Star or chain 2 3 levels N/A

GRFU 2 l GRFU

V1: 1.25

Gbit/s

l GRFU

V2:

1.25/2.5

Gbit/s

Star or chain 6 2 levels N/A

RRU300

4

2 1.25 Gbit/s Star, chain, or

ring

2 6 levels 40

RRU300

8

2 l RRU300

8 V1

(850, or

1900

MHz):

1.25 Gbit/

s

l RRU300

8 V1

(1800

MHz) or

RRU300

8 V2:

1.25/2.5

Gbit/s

Star, chain, or

ring

8 6 levels 40





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RFModules

Number ofCPRIPorts

Data Rate Topology Number ofSupportedCarriers

CascadingLevels

MaximumDistance

fromtheBBU

MRFU

V1

2 1.25 Gbit/s Star 6 N/A N/A

MRFU

V2

2 1.25/2.5

Gbit/s

Star 6 N/A N/A

MRFUd 2 1.25/2.5

Gbit/s

Star 8 N/A N/A

MRFUe 2 1.25/2.5Gbit/s

Star 8 N/A N/A

RRU390

8 V1

2 l RRU390

8 V1

(850, 900,

or 1900

MHz):

1.25 Gbit/

s

l RRU390

8 V1

(1800MHz):

1.25/2.5

Gbit/s

Star 6 N/A 40

RRU390

8 V2

2 1.25/2.5

Gbit/s

Star 8 N/A 40

RRU392

8

2 1.25/2.5

Gbit/s

Star 8 N/A 40

RRU392

9

2 1.25/2.5

Gbit/s

Star 8 N/A 40

RRU394

2

2 1.25/2.5

Gbit/s

Star 8 N/A 40

RRU392

6

2 1.25/2.5

Gbit/s

Star, chain, or

ring

8 21 40

5.4 RRU3004 Configuration

RRU3004 is a double-transceiver remote radio unit and supports two carriers. Differentconfigurations must be chosen in different topologies.





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Port

Table 5-4 describes major ports on RRU3004.

Table 5-4 Major ports on RRU3004

Type Silkscreen Description

Port for transceiving RF

signals

ANT_TX/RXA and

ANT_TX/RXB

The two ports, each of which is used

to transmit and receive RF signals,

connect to the antenna system

through antenna channel 1 and

antenna channel 2 respectively.

CPRI port TX RX CPRI_W The port is a westbound optical/

electrical port and it is used to connect

to the BBU or an upper-level RRU.

TX RX CPRI_E The port is an eastbound optical/


to a lower-level RRU.

Interconnection port for

receiving RF signals

RX_IN/OUT The port is used to transmit and

receive the diversity signals received

through an antenna channel.

Basic Configurations

Table 5-5 lists the basic configurations of an RRU3004 serving only one sector.

The format of the description of the basic configuration is RF[F][TX][RX]_[C][TYPE]. Where,

l F indicates the number of antenna channels for an RF module.

l TX indicates the number of transmit channels for an RF module.

l RX indicates the number of receive channels for an RF module.

l C indicates the number of CPRI links connecting RF modules with the GTMU board.

l TYPE indicates the CPRI network topologies applied to connect RF modules with the BBU.

If the value of TYPE is A, the star topology is applied. If the value of TYPE is B, the chaintopology is applied.

Table 5-5 Basic configurations

BasicConfiguration

Number ofModules

SendingReceiving Mode

HardwareConfiguration

RF111_1A 1 Single feeder

[1TX 1RX]

Figure 5-10

RF211_1A 1 Double feeder

[1TX 1RX]

Figure 5-11





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BasicConfiguration

Number ofModules




[1TX 2RX]

Figure 5-12


[2TX 2RX]

Figure 5-13

RF112_2B 2 Single feeder

[1TX 2RX]

Figure 5-14

RF111_1A

An RRU3004 connects to the antenna system through ANT_TX/RXA. Antenna channel 1

transmits and receives signals. The star topology is applied to connect the BBU with theRRU3004.

Figure 5-10 RF111_1A

RF211_1A

An RRU3004 connects to the antenna system through ANT_TX/RXA and ANT_TX/RXB.

Antenna channel 1 transmits signals while antenna channel 2 receives signals. The star topology

is applied to connect the BBU with the RRU3004.





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RF212_1A


Antenna channel 1 transmits and receives signals while antenna channel 2 receives signals only.The star topology is applied to connect the BBU with the RRU3004.






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RF222_1A

An RRU3004 connects to the antenna system through ANT_TX/RXA and ANT_TX/RXB. Both

antenna channel 1 and antenna channel 2 transmit and receive signals. The star topology is

applied to connect the BBU with the RRU3004.


RF112_2B

Two RRU3004 connect to the antenna system through ANT_TX/RXA. Antenna channel 1

transmits and receives signals. RX_IN/OUT on the two RRU3004 interconnect to transfer

diversity signals. The chain topology is applied to connect the BBU with one RRU3004.





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Figure 5-14 RF112_2B

Typical Configurations

Table 5-6 describes the typical configurations of RRU3004 in different scenarios.

Table 5-6 Typical configurations

Scenario

Number ofModules

Send Mode Typical Configuration

S1 1 Transmit diversity RF222_1A

Independent transmit l RF111_1A

l RF212_1A

l RF222_1A

S2 1 Independent transmit or

combination

l RF111_1A

l RF212_1A

l RF222_1A

2 PBT RF112_2B


combination

RF112_2B


combination

l RF112_2B

l RF111_1A + RF111_1A





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5.5 Configurations of RRU3008, RRU3908, RRU3928,RRU3929, RRU3942, RRU3926, and the MRFUd

RRU3008, RRU3908, RRU3928, RRU3929, RRU3942, and RRU3926 are multi-carrier remote

radio units. An RRU3908 V1 supports a maximum of six carriers. RRU3908 V2 and other

modules support a maximum of eight carriers each. MRFUd is a multi-carrier radio frequency

(RF) module and supports a maximum of eight carriers. RF configuration modes need to be

selected depending on networking configurations.

Port

Table 5-7 describes major ports on RRU3008 V1.

Table 5-7 Major ports on RRU3008 V1


RF port ANT-A and ANT-B The two ports, each of which is used







to the BBU or an upper-level RRU.



to a lower-level RRU.






Table 5-8 describes major ports on RRU3008 V2 and RRU3908 V2.

Table 5-8 Major ports on RRU3008 V2 and RRU3908 V2


RF port ANT_TX/RXA and

ANT_TX/RXB






CPRI port CPRI0 The port is used to connect to the

BBU or an upper-level RRU.





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CPRI1 The port is used to connect to the

BBU or a lower-level RRU.

Interconnection port forreceiving RF signals

RX_IN/OUT The port is used to transmit andreceive the diversity signals received


Table 5-9 describes major ports on RRU3908 V1.

Table 5-9 Major ports on RRU3908 V1


RF port ANT-A and ANT-B The two ports, each of which is used







to the BBU.



to the BBU.






Table 5-10 describes major ports on RRU3928 or RRU3929.

Table 5-10 Major ports on RRU3928 or RRU3929



ANT_TX/RXB






CPRI port CPRI0 The port is optical/electrical port 0

and it is used to connect to the BBU.

CPRI1 The port is optical/electrical port 1






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Table 5-11 describes major ports on the MRFUd.

Table 5-11 Major ports on the MRFUd



ANT_TX/RXB



connect to the antenna systemthrough antenna channel 1 and


CPRI port CPRI0 The port is used to connect to the

BBU.


BBU.



RX_INB The port is used to receive diversity

signals from an antenna channel.

RX_OUTA The port is used to transmit diversitysignals to an antenna channel.




RF port ANT_TX/RXA,

ANT_RXC, ANT_RXD,ANT_TX/RXB


to transmit and receive RF signals,connect to the antenna system
















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RF port ANT_TX/RXA,

ANT_RXB
















The basic configurations of RRU3008, RRU3908, RRU3928, RRU3929, RRU3942, RRU3926,and the MRFUd are the same. The following description takes RRU3008 V2 as an example.

Table 5-14 lists the basic configurations of a single sector.

The basic configurations are described in the "RF[F][TX][RX]_[C][TYPE]" format. Where,






If the value of TYPE is A, the star topology is applied. If the value of TYPE is B, the chaintopology is applied.


BasicConfiguration

Number ofModules




[1TX 1RX]

Figure 5-15

RF112_2B 2 Single feeder

[1TX 2RX]

Figure 5-16





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BasicConfiguration

Number ofModules




[1TX 1RX]

Figure 5-17


[1TX 2RX]

Figure 5-18


[2TX 2RX]

Figure 5-19

RF111_1A

An RRU3008 connects to the antenna system through ANT_TX/RXA. Antenna channel 1

transmits and receives signals. The star topology is applied to connect the BBU with theRRU3008.


RF112_2B

Two RRU3008 connect to the antenna system through ANT_TX/RXA. Each antenna channel

1 transmits and receives signals. RX_IN/OUT on the two RRU3008 interconnect to transfer

diversity signals. The chain topology is applied to connect the BBU with one RRU3008.





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Figure 5-16 RF112_2B

RF211_1A


Antenna channel 1 transmits signals while antenna channel 2 receives signals. The star topologyis applied to connect the BBU with the RRU3008.






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RF212_1A


Antenna channel 1 transmits and receives signals while antenna channel 2 receives signals only.

The star topology is applied to connect the BBU with the RRU3008.


RF222_1A

An RRU3008 connects to the antenna system through ANT_TX/RXA and ANT_TX/RXB. Each

antenna channel transmits and receives signals. The star topology is applied to connect the BBU

with the RRU3008.





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Table 5-15 describes the typical configurations of RRU3008 in different scenarios.

Table 5-15 Typical configurations

Scenario Number ofModules

Send Mode Typical Configuration

S3-S8 1 Independent transmit RF212_1A

Transmit diversity (S4) RF222_1A

S8-S12 2 Combined transmit RF112_2B

Independent transmit RF222_1A + RF222_1A

5.6 DRFU Configuration

The DRFU is a double-transceiver module and supports two carriers. Different configurations

must be chosen in different topologies.

Port

Table 5-16 describes major ports on the DRFU.





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Table 5-16 Major ports on the DRFU


Port for transceiving RF

signals

ANT1 and ANT2 The two ports, each of which is used

to transmit and receive RF signals,connect to the antenna system



CPRI port CPRI0 The port is used to connect to a lower-

level DRFU.


BBU or an upper-level DRFU.



RX1/IN and RX1/OUT RX1/IN is the diversity receive port

for antenna channel 1 while RX1/

OUT is the diversity transmit port forantenna channel 1.

RX2/IN and RX2/OUT RX2/IN is the diversity receive port

for antenna channel 2 while RX2/

OUT is the diversity transmit port for

antenna channel 2.


Table 5-17 lists the basic configurations of a DRFU serving only one sector.

The format of the description of the basic configuration is RF[F][TX][RX]_[C][TYPE]. Where,






If the value of TYPE is A, the star topology is applied. If the value of TYPE is B, the chain

topology is applied.


BasicConfiguration

Number ofModules




[1TX 1RX]

Figure 5-20


[1TX 1RX]

Figure 5-21


[1TX 2RX]

Figure 5-22





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BasicConfiguration

Number ofModules




[2TX 2RX]

Figure 5-23


[1TX 2RX]

Figure 5-24


[2TX 4RX]

Figure 5-25

RF111_1A

A DRFU connects to the antenna system through ANT1. Antenna channel 1 transmits and

receives signals.


RF211_1A

A DRFU connects to the antenna system through ANT1 and ANT2. Antenna channel 1 transmitssignals while antenna channel 2 receives signals.





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RF212_1A

A DRFU connects to the antenna system through ANT1 and ANT2. Antenna channel 1 transmits

and receives signals while antenna channel 2 receives signals only.





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RF222_1A

A DRFU connects to the antenna system through ANT1 and ANT2. Both antenna channel 1 and

antenna channel 2 transmit and receive signals.





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RF112_2A

Two DRFUs connect to the antenna system through ANT1. Antenna channel 1 transmits and

receives signals. RX1/IN on one DRFU interconnects with RX1/OUT on the other DRFU to

transfer the diversity signals received through antenna channel 1.





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RF224_2A

Two DRFUs connect to the antenna system through their own ports ANT1 and ANT2. Both

antenna channel 1 and antenna channel 2 transmit and receive signals. RX1/IN on one DRFU

interconnects with RX1/OUT on the other DRFU to transfer the diversity signals received

through antenna channel 1. RX2/IN on one DRFU interconnects with RX2/OUT on the other

DRFU to transfer the diversity signals received through antenna channel 2.





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Table 5-18 describes the typical configurations of the DRFU in different scenarios.

Tabl

Documents

123325177 Huawei BTS 3900 Technical Description