zte1

8/10/2019 zte1

1/113

ZXCBTS CDMA Micro base Station/Remote Station Technical Description

ZTE Confidential Proprietary

ZXCBTS CDMA Micro Base Station/Remote Station

Technical Description

About the Document:

Version Status Date Author Approved By Remarks

V2.0 2004-02-10

Copyright Notice:

Copyright 2003 ZTE Corporation Shenzhen P. R. China

All rights reserved. No part of this documentation may be excerpted, reproduced, translated,

annotated or duplicated, in any form or by any means without the prior written permission of ZTE

Corporation.

8/10/2019 zte1

2/113


I

Table of Contents1 Technical Introduction ..........................................................................................................................1

1.1 System Overview....................................................................................................................... 1

1.2 Position of Micro-BTS in an Entire CDMA System................................................................. 2

1.3 Structure of Micro-BTS System................................................................................................ 3

1.4 Functions ...................................................................................................................................4

1.5 System Features......................................................................................................................... 5

1.6 Standards Followed ...................................................................................................................6

2 Network Architecture ............................................................................................................................ 92.1 Requirements for Environmental Indices of Equipment Operation .......................................... 9

2.2 Performance Indices ................................................................................................................ 12

3 Hardware of Micro Base Transceiver Stations.................................................................................... 22

3.1 Overview of Hardware Structure............................................................................................. 22

3.2 BDS .........................................................................................................................................26

3.3 RFS..........................................................................................................................................26

3.4 TFS ..........................................................................................................................................34

3.5 Transmission Subsystem .........................................................................................................36

3.6 Power Subsystem..................................................................................................................... 41

4 Software of Micro Base Transceiver Stations ..................................................................................... 44

4.1 Overview of Micro-BTS Software .......................................................................................... 44

4.2 BDM Software......................................................................................................................... 44

4.3 MTRX Software ......................................................................................................................63

5 Networking and Configuration............................................................................................................ 70

5.1 Networking Modes and Examples of Micro-BTS................................................................... 70

5.2 System Configuration.............................................................................................................. 75

6 Terminology and Abbreviation ........................................................................................................... 81

8/10/2019 zte1

3/113


II

Figure and Table

Figue:

Fig. 1 Naming Rules for ZXCBTS CDMA Micro Base Transceiver Station

and Remote Station Products .................................................................................. 2

Fig. 2 Position of a Micro-BTS in a BSS....................................................................... 2

Fig. 3 Interfaces of ZXCBTS CDMA Micro-BTS......................................................... 3

Fig. 4 Structure of ZXCBTS M800/M802/M190/M191/M192 Micro-BTS.................. 4Fig. 5 Photo of a Micro-BTS (I)..................................................................................... 9

Fig. 6 Logical Structure of Micro-BTS........................................................................ 23

Fig. 7 Block Diagram of the Micro-BTS System......................................................... 23

Fig. 8 Photo of a Micro-BTS........................................................................................ 24

Fig. 9 Structure of ZXCBTS CDMA Remote Station.................................................. 25

Fig. 10 Position of RFS in a CDMA Micro-BTS......................................................... 27

Fig. 11 Single-Carrier Single-Sector RFS Subsystem.................................................. 28

Fig. 12 Two-Carrier Single-Sector RFS....................................................................... 29

Fig. 13 Single-Carrier Two-Sector RFS....................................................................... 30

Fig. 14 Position of MGPSTM in a Micro-BTS............................................................ 34

Fig. 15 Units in the ZXSM T150 System..................................................................... 37

Fig. 16 Block Diagram of the Power Subsystem (220V AC input) ............................. 42

Fig. 17 Block Diagram of the Power Subsystem (-48V DC input).............................. 42

Fig. 18 General Structure of the Software System....................................................... 45

Fig. 19 Position of OSS in System Software and Its Modules..................................... 46

Fig. 20 Structure of the Foreground Database Subsystem........................................... 49

Fig. 21 Processes and External Interfaces of RCM...................................................... 53

Fig. 22 Structure of OMS............................................................................................. 56

Fig. 23 Software Module Structure of 1X CES ........................................................... 62

Fig. 24 Position of MTRX in System........................................................................... 64

Fig. 25 Networking of ZXCBTS CDMA Micro-BTS and Remote Station................. 70

Fig. 26 Solution of AC Micro-BTS + UPS Power Builtin SDH................................... 71

Fig. 27 Solution of DC Micro-BTS + Combinational Power + Builtin SDH .............. 72

Fig. 28 Point-To-Point and Chain Networking Modes of Built-in SDH....................... 73

Fig. 29 Ring Networking of Builtin SDH .................................................................... 73

8/10/2019 zte1

4/113


III

Fig. 30 Networking of Micro-BTS with Cooperation of Standard SDH Device .......... 73

Fig. 31 Hybrid Networking of Builtin Micro-BTS and Standard SDH ....................... 74

Fig. 32 Cell Splitting Solution of Micro-BTS or Remote Station................................ 74Fig. 33 Single-Carrier Single-Sector Configuration of Micro-BTS/Remote

Station ................................................................................................................... 76

Fig. 34 Single-Carrier Two-Sector Configuration of Micro-BTS/Remote

Station ................................................................................................................... 77

Fig. 35 Single-Carrier Three-Sector Configuration of Micro-BTS/Remote

Station ................................................................................................................... 78

Fig. 36 Two-Carrier Single-Sector Configuration of Micro-BTS/Remote

Station ................................................................................................................... 79

Table:

Table 1 Fully Loaded Power Consumptions of Several Micro Cells and

Remote Stations in 220V AC Power Supply Mode.............................................. 10

Table 2 Power Consumptions of Several Fully Loaded Micro Cells and

Remote Stations Configured with a Heater in 220V AC Power Supply

Mode ..................................................................................................................... 10

Table 3 Power Consumptions of Several Fully Loaded Micro Cells and

Remote Stations in -48V DC Power Supply Mode............................................... 11

Table 4 Electrostatic Discharge Immunity................................................................... 13

Table 5 Radiated RF Electromagnetic Field Immunity................................................ 13

Table 6 Electrical Fast Transient/Burst Immunity ....................................................... 14Table 7 Surge Immunity of Micro-BTSs and Remote Stations ................................... 14

Table 8 Immunity to Conducted Disturbances and Induced by Radio-

Frequency Field..................................................................................................... 14

Table 9 Limits for Radiated Spurious Disturbances of the Shelf Port ......................... 15

Table 10 Limits for Conducted Disturbances of Power Port Not in a

Telecommunication Center ................................................................................... 15

Table 11 Limits for Conducted Disturbances of the Signal and Control Line

Port........................................................................................................................ 16

Table 12 Outband Spurious Requirements of IS97 BAND CLASS0

CDMA800 CELLULAR....................................................................................... 18Table 13 Out band Spurious Requirements of IS97 BAND CLASS1

CDMA1900 PCS................................................................................................... 18

Table 14 Access Attempt Failure Table ....................................................................... 18

Table 15 Unit/Board Configuration of ZXCBTS

M800/M802/M190/M191/M192 Micro-BTS ....................................................... 75

Table 16 Unit/Board Configuration of ZXCBTS R800/R802/R190/R191/R192

Remote Station...................................................................................................... 75

8/10/2019 zte1

5/113


IV

Table 17 Single-Carrier Two-Sector Configuration of a Micro-BTS and a

Remote Station...................................................................................................... 77

Table 18 Single-Carrier Three-Sector Configuration Composed of one Micro-

BTS and Two Remote Stations............................................................................. 78

Table 19 Two-Carrier Single-Sector Configuration Composed of a Micro-BTS

and a Remote Station ............................................................................................ 79

Table 20 Terminology and Abbreviations in the document.......................................... 81

8/10/2019 zte1

6/113

ZTE Confidential Proprietary 1

1 TECHNICAL INTRODUCTION

1.1 System Overvi ew

With the continuous emergence of new technologies, intelligent Base Transceiver Stations

(hereinafter called BTS for short) with small size, low power consumption, low cost and highreliability become the development trend. With the increase of tall buildings in large and

medium cities day by day, ordinary macro BTSs cannot meet the requirement for coverage in

partial hotspot areas. However, in remote regions that need wide coverage and only have a

small number of users, the application of high-capacity macro BTSs cannot put the equipment

into full play, and furthermore, the equipment room environment in remote regions can hardly

meet the requirements of macro BTSs. To satisfy the market needs, ZTE CORPORATION

develops ZXCBTS CDMA micro base transceiver station and remote station products.

In coastlands, it is required that the coverage of a BTS on offing surface should reach

60km~100km. Likewise, in inland prairies, deserts and forests, the coverage also should reach

40km~80km. According to the geographical distribution of China and to meet the market needs,

ZTE CORPORATION has developed ultra-wide coverage micro-BTSs with higher power.

ZXCBTS CDMA micro base transceiver station and remote station products are series of BTS

products in the ZXC10-BSS system. The series of products are as follows: ZXCBTS M800

(800MHz micro-BTS with the Tx power of the power amplifier of 10W), ZXCBTS M802

(800MHz micro-BTS with the Tx power of the power amplifier of 20W), ZXCBTS M804

(800MHz ultra-wide coverage micro-BTS with the Tx power of the power amplifier of 40W),

ZXCBTS M190 (1900MHz micro-BTS with the Tx power of the power amplifier of 5W),



ZXCBTS R800 (800MHz remote station with the Tx power of the power amplifier of 10W),

ZXCBTS R802 (800MHz remote station with the Tx power of the power amplifier of 20W),ZXCBTS R804 (800MHz remote station with the Tx power of the power amplifier of 40W),

ZXCBTS R190 (1900MHz remote station with the Tx power of the power amplifier of 5W),

ZXCBTS R191 (1900MHz remote station with the Tx power of the power amplifier of 10W)

and ZXCBTS R192 (1900MHz remote station with the Tx power of the power amplifier of

20W). The series of products support IS-2000 1X and related standards.

ZXCBTS CDMA micro base transceiver station and remote station products are named in the

way shown as following.

8/10/2019 zte1

7/113



ZXCBTS XXXX1--with an amplifier power of 10W,; 2-- with an amplifierpower of 20W; 3-- with an amplifier pow er of 40W

45--450MHz band; 80--800MHz band; 19--1900MHz bandM--Indicates Micro Base Transceiver StationR--Indicates Remote Station

BTS--Indicates Base Transceiver Station

C--Indicates CDMA mobile products

ZX--Indicates ZTE CORPORATION

Fig. 1 Naming Rules for ZXCBTS CDMA Micro Base Transceiver Station and Remote Station

Products

1.2 Positi on of Micro -BTS in an Entire CDMA System

The position of a micro-BTS in a BSS (Base Station Subsystem) is shown as following.

MSC

PDSN

Um

interfaceMS

BSC

C

DS

U

C

DS

U

S

VI

CM

P

C

F

RF

S

B

DS

MS

Micro-BTS

RF

S

B

DS

Micro-BTS

Um

interface

A interface

A10/A11

interface

Abis

interface

Fig. 2 Position of a Micro-BTS in a BSS

The ZXCBTS CDMA micro-BTS is connected to mobile stations via an air interface Um, and is

connected to the Base Station Controller (BSC) via an Abis interface, as shown as following.

8/10/2019 zte1

8/113



ZXCBTS M800

ZXCBTS M802

ZXCBTS M190

ZXCBTS M191

ZXCBTS M192

ZXC10-BSC

Mobile

station CDMA micro-BTS CDMA BSCUm interface Abis interface

Fig. 3 Interfaces of ZXCBTS CDMA Micro-BTS

1.3 Structu re of Micro -BTS System

A ZXCBTS CDMA micro-BTS is composed of six subsystems: Baseband Digital Subsystem(BDS), Timing & Frequency Subsystem (TFS), Radio Frequency Subsystem (RFS), power

subsystem, lightning-protection subsystem and 155M SDH optical transmission subsystem

(optional). The BDS completes the baseband modulation/demodulation of CDMA signals and

also provides functions such as resources management, signaling processing and operation &

maintenance. In addition, the BDS provides an Abis interface with the BSC. The TFS provides

time and frequency signals necessary for the BDS and RFS. By means of an antenna, the RFS

provides an air interface, completes the modulation transmitting and demodulation receiving of

CDMA signals and implements related detection, monitor, configuration and control functions.

The power subsystem supplies power for the entire system. The lightning protection of a micro-

BTS consists of antenna feeder lightning protection, power lightning protection and signal line

lightning protection. The antenna feeder lightning protection involves lightning protection ofthe Tx/Rx antennas and the GPS antenna feeder. The 155M SDH optical transmission

subsystem completes optical-electrical conversion. The module is an optional module. When a

user uses a micro-BTS, if there is no optical transmission equipment but only fibres are led to

the site, the module can be configured. The user does not need to buy any transmission

equipment. Thus, the engineering construction period can be shortened and the coordination

and management workload of the user can be reduced.

The structure of a ZXCBTS M800/M802/M190/M191/M192 micro-BTS is shown as following.

8/10/2019 zte1

9/113



Optional

RF transmitting

Tx/Rx antennaGPS receiving

antenna

Micro-BTS

Lightning-

protection unit

BDS

(BDM)

TFS

(GPSTM) Power

E1 (four)

SDH (155M)

subsystemFiber

RFS (MTRX,

MPA, MLNA

and RFE)

Fig. 4 Structure of ZXCBTS M800/M802/M190/M191/M192 Micro-BTS

1.4 Functions

The section describes the functions and implementation of micro-BTSs and the technologiesapplied.

Functions of micro-BTSs:

1. Supporting air interface specifications of EIA/TIA IS-2000, EIA/TIA IS97-C and

TSB74;

2. Supporting CDMA 800MHz and 1900MHz frequency configuration;

3. Supporting the control over Transmission Power Track Loop (TPTL) of BTS in the

CDMA cellular system;

4. Providing normal call, Markov call and loopback call services;

5. Providing land circuit management and radio resources management;

6. Supporting hand-off control from micro-BTSs to micro-BTSs and micro-BTSs to macro

BTSs;

8/10/2019 zte1

10/113



7. Providing equipment operation & maintenance, covering performance management,

alarm management, configuration management, diagnosis management and security

management;

8. Supporting built-in 155M SDH optical transmission subsystem;

9. Supporting monitor over external power.

1.5 System Features

During the design and development of the ZXCBTS CDMA micro-BTS/remote station system,

we fully absorb the features of the existing CDMA systems and also make improvements

according to the new requirements of carriers. The features of the ZXCBTS CDMA micro-

BTS/remote station system are as follows:

1. Advanced performance: The ZXCBTS CDMA micro-BTS/remote station system fully

absorbs the advantages of existing CDMA micro-BTS and remote station products

home and abroad to maintain advanced system design.

2. Forward compatibility: In the system design, the transition to the third generation of

mobile communications system is taken into full consideration so that the system can

smoothly evolve into the 3G system targeting at cdma2000.

3. High integrity: Large quantities of advanced devices and design technologies are

applied to the ZXCBTS CDMA micro-BTS/remote station system so that the system

integrity is improved and the type and number of modules are reduced.

4. Compact structure: The shelf is of compatible indoor and outdoor wall-mounted

structure. The micro-BTS/remote station is of compatible structure. With simple module

replacement or shelf adding/deleting, the mutual conversion between micro-BTS/remote

station products can be implemented.

5. High reliability: The ZXCBTS CDMA micro-BTS/remote station system is designed

with high integrity. Only a small number of module types are used. The advanced fault

tolerance software design is taken to improve the system reliability.

6. Flexible configuration: ZXCBTS CDMA micro-BTSs and remote stations can be

combined to implement multiple configurations. A micro-BTS can be directly connected

to a Channel/Data Service Unit (CDSU) in the BSC or can be connected to the original

8/10/2019 zte1

11/113



macro BTS in daisy chain mode. Furthermore, the daisy connections between ultra-wide

coverage micro-BTSs and micro-BTSs, between ultra-wide coverage micro-BTSs and

between micro-BTSs are supported. New micro-BTSs and ultra-wide coverage micro-BTSs will not affect the arrangement and connection of existing BSCs and macro BTSs.

A single micro-BTS or a single ultra-wide coverage micro-BTS can implement single-

carrier omni-direction, and if configured with a remote station system, it can implement

the system configurations of single-carrier two-sector, single-carrier three-sector,

two-carrier single-sector and three-carrier single-sector. The remote station system

can be connected to the micro-BTS or to the macro BTS.

7. The micro-BTS is configured with a builtin 155M SDH optical transmission subsystem

to save users investment and improve the construction speed.

8. The system supports the monitor over external powers (via dry contact or 485 interface)

to facilitate monitor, management and maintenance of the system operation.

1.6 Standards Followed

The micro-BTSs and remote stations follow the following standards:

1. Physical Layer Standard for cdma2000 Spread Spectrum Systems Release 0;

2. Medium Access Control (MAC) Standard for cdma2000 Spread Spectrum Systems

Release 0;

3. Signaling Link Access Control (LAC) Specification for cdma2000 Spread Spectrum

Systems Release 0;

4. Upper Layer (Layer3) Signaling Standard for cdma2000 Spread Spectrum Systems

Release 0;

5. ITU-T G.652 Characteristics of a single-mode optical fibre and cable

6. ITU-T G.703 Physical/electrical characteristics of hierarchical digital interfaces

7. ITU-T G.704 Synchronous frame structures used at 1544, 6312, 2048, 8448 and 44 736

kbit/s hierarchical levels

8. ITU-T G.707 Network node interface for the synchronous digital hierarchy

8/10/2019 zte1

12/113



9. ITU-T G.773 Protocol suites for Q-interfaces for management of transmission systems

10. ITU-T G.774 Synchronous digital hierarchy (SDH) - Management information model

for the network element view

11. ITU-T G.780 Vocabulary of terms for synchronous digital hierarchy (SDH) networks

and equipment

12. ITU-T G.783 Characteristics of synchronous digital hierarchy (SDH) equipment

functional blocks

13. ITU-T G.784 Synchronous digital hierarchy (SDH) management

14. ITU-T G.803 Architecture of transport networks based on the synchronous digital

hierarchy

15. ITU-T G.811 Timing characteristics of primary reference clocks

16. ITU-T G.812 Timing requirements of slave clocks suitable for use as node clocks in

synchronization networks

17. ITU-T G.813 Timing characteristics of SDH equipment slave clocks

18. ITU-T G.823 The control of jitter and wander within digital networks which are based

on the 2048 kbit/s hierarchy

19. ITU-T G.825 The control of jitter and wander within digital networks which are based

on the synchronous digital hierarchy (SDH)

20. ITU-T G.831 Management capabilities of transport networks based on the synchronous

digital hierarchy

21. ITU-T G.832 Transport of SDH elements on PDH networks - Frame and multiplexing

structures

22. ITU-T G.841 Types and characteristics of SDH network protection architectures

23. ITU-T M.3010 Principles for a Telecommunications management network

24. ITU-T M.3400 TMN Management Functions

8/10/2019 zte1

13/113



25. ITU-T Q.811 Lower layer protocol profiles for the Q3 and X interfaces

26. ITU-T Q.812 Upper layer protocol profiles for the Q3 and X interfaces

8/10/2019 zte1

14/113


2 NETWORKARCHITECTURE

2.1 Requirements for Environmental Indices of Equipment

Operation

2.1.1 Physical Indices

2.1.1.1 Dimensions

Dimensions of a single cabinet: The dimensions of the integrated equipment (height width

depth): 630mm 400mm 285mm.

The internal design capacity is about 580mm 396mm 200mm. For details, please refer to

the following figure.

Fig. 5 Photo of a Micro-BTS (I)

2.1.1.2 Weight

Weight of a single shelf: About 37kg.

8/10/2019 zte1

15/113



2.1.1.3 Color

The micro-BTS cabinet is in silver gray.

2.1.2 Equipment Power

2.1.2.1 Power System Range

The shelves of micro-BTSs (ultra-wide coverage micro-BTSs as well) and remote stations are

supplied with power in two modes: 220V AC power supply and -48V DC power supply.

220V AC power, with a power supply range: 150V~300V/45Hz~65Hz;

-48V DC power, with a power supply range: -40~-57V.

2.1.2.2 Power Consumption Indices

The fully loaded power consumptions of several micro cells and remote stations in 220V AC

power supply mode are shown as following.

Table 1 Fully Loaded Power Consumptions of Several Micro Cells and Remote Stations in

220V AC Power Supply Mode

Type Power Consumption

M190 165W

M191 180W

M192 275W

M800 180W

M802 275W

R190 165W

R191 180W

R192 275W

R800 180W

R802 275W

Note: The power factor of the system is 0.5

The power consumptions of several fully loaded micro cells and remote stations configured

with a heater in 220V AC power supply mode are shown as following.

Table 2 Power Consumptions of Several Fully Loaded Micro Cells and Remote Stations

Configured with a Heater in 220V AC Power Supply Mode

Type Power Consumption (unit: W)

8/10/2019 zte1

16/113




M190 265W

M191 280W

M192 375W

M800 280W

M802 375W

R190 265W

R191 280W

R192 375W

R800 280W

R802 375W

Note 1: The power factor of the system is 0.5

Note 2: A heater module should be configured when the minimum temperature in the place where the equipment is used is less than -

10C. At present, only the 220V AC equipment provides this function. The DC equipment does not provide the function.

The power consumptions of several fully loaded micro cells and remote stations in -48V DC

power supply mode are shown as following.

Table 3 Power Consumptions of Several Fully Loaded Micro Cells and Remote Stations in -

48V DC Power Supply Mode


M190 165W

M191 180W

M192 275W

M800 180W

M802 275W

R190 165W

R191 180W

R192 275W

R800 180W

R802 275W

2.1.3 Grounding Requirements

The grounding resistance of the shelf should be less than or equal to five ohms.

8/10/2019 zte1

17/113



2.1.4 Requirements for Temperature and Humidi ty

The micro-BTS equipment should be able to operate reliably and stably in the following

environmental conditions for a long period of time:

Operating temperature: -30C ~+55C;

Storage temperature: -40C ~+75C;

Relative humidity: 5%~98%.

2.1.5 Conditions of Mechanical Active Materials

1. Sand density 1000mg/m3;

2. Floating dust density 15mg/m3;

3. Sediment dust density 1000mg/m2

.d.

2.2 Performance Indices

2.2.1 Interface Indices

1. Electrical interface (E1):

Rate: 2.048Mbps 50ppm;

Impedance: 75unbalanced;

Code pattern: HDB3.

2. Optical interfaces (built-in SDH):

Line rate: 155.520Mbps;

Wavelength: 1310nm/1550nm;

Line code pattern: NRZ;

Spectrum width:

8/10/2019 zte1

18/113



2.2.2.2 Capacity Indices of Remote Station

A remote station does not have any digital baseband unit by itself, and its CE unit is assigned

by the digital baseband unit of a macro BTS or a micro-BTS.

2.2.3 Reliability Indices

2.2.3.1 System Indices

The Mean Time Between Failures (MTBF) of ZXCBTS is greater than 50000 hours;

And the Availability (A) of the product in twenty years is equal to 99.9995%.

2.2.3.2 EMC Indices

The EMC indices are in compliance with Part 2, Base Transceiver Station and Its AuxiliaryEquipment in YD 1169.2-2001 EMC Requirements and Measurements of 800MHz CDMA

Digital Cellular Mobile Communications System released by the Ministry of Information

Industry.

1. The electrostatic discharge immunity of micro-BTSs and remote stations is shown as

following.

Table 4 Electrostatic Discharge Immunity

Standard Stress Grade Performance Criterion Applicable Port

IEC61000-4-2 (1995)

EN 301 489-26 (2001-9)

YD 1169.2-2001

Contact 6kV;

Air 8kVB

Applicable to any surface

that may expose in EUT

operation and in

maintenance of the

operation personnel

2. The radiated RF electromagnetic field immunity of micro-BTSs and remote stations is

shown as following.

Table 5 Radiated RF Electromagnetic Field Immunity

Standard Stress GradePerformance

CriterionAppl icable Port

IEC61000-4-3 (1995)

EN 301 489-26 (2001-9)

YD 1169.2-2001

(27MHz) 80MHz800MHz:10V/m;

800MHz960MHz: 10V/m;

960MHz1400MHz: 10V/m;

1400MHz2000MHz: 10V/m.

AApplicable to the

integrated equipment

3. The electrical fast transient/burst immunity of micro-BTSs and remote stations is shownas following

8/10/2019 zte1

19/113



Table 6 Electrical Fast Transient/Burst Immunity

Standard Stress Grade PerformanceCriterion

Appl icable Port

IEC61000-4-4 (1995)

EN 301 489-26 (2001-9)

YD 1169.2-2001

Communication port: 2kV;

Antenna feeder port: 2kV;

Power port: 2kV;

B

Communication port

Signal and control port

DC power port

4. The surge immunity of micro-BTSs and remote stations is shown as following.

Table 7 Surge Immunity of Micro-BTSs and Remote Stations



IEC61000-4-5 (1995)

ITU-T K.20

EN 301 489-26 (2001-9)

YD 1169.2-2001

Communication port: 4kV

(1.2/50, 8/20);

Antenna feeder port: 6kV

(1.2/50, 8/20);

Power port: common mode

6kV, differential mode 6kV

(1.2/50, 8/20)

B

Communication port

Signal and control

port

Power port

5. The immunity to conducted disturbances and Induced by radio-frequency field of

micro-BTSs and remote stations is shown as following.

Table 8 Immunity to Conducted Disturbances and Induced by Radio-Frequency Field



IEC61000-4-6 (1995)

EN 301 489-26 (2001-9)

YD 1169.2-2001

Communication port, signal and

control port:

3V rms, 150kHz80MHz;

DC power port:

3V rms, 20kHz80MHz

A

Communication port

Signal and control

port

Power port

6. Voltage dips, short interruptions and voltage variations immunity

Standard: IEC61000-4-11, YD 1169.2-2001

Applicable port: AC power port

1) The power supply voltage drops by 30%, lasting 10ms;

8/10/2019 zte1

20/113



2) The power supply voltage drops by 60%, lasting 100ms;

3) The power supply voltage drops over >95%, lasting 5000ms.

7. Radiated spurious disturbance of shelf port

Standard: YD 1169.2-2001;

Applicable port: shelf;

The limits for the spuriously radiated disturbance of the shelve port are shown as following.

Table 9 Limits for Radiated Spurious Disturbances of the Shelf Port

Frequency Range Limi t (peak value)

30 MHz 88 MHz -57dBm



960 MHz 10000MHz -43dBm

8. Conducted disturbances of power port

Standard: CISPR22 (1997), EN 301 489-26 (2001-9), YD 1169.2-2001;

Applicable port: Power port;

Limit: CLASS B;

The limits for conducted disturbances of the AC power port not in a telecommunication center

are shown as following.

Table 10 Limits for Conducted Disturbances of Power Port Not in a Telecommunication Center

Limit (dBV)Frequency Range (MHz)

Quasi-peak Value Average Value

0.15 ~0.50 66~56 56~46

0.50 ~ 5 56 46

5~30 60 50

Note:

1. A lower limit should be used at transitional frequencies (0.50MHz and 5MHz);2. The limit decreases linearly with the logarithm of the frequency in the range of 0.15~0.50MHz.

9. Conducted disturbances of signal and control line port

Standard: CISPR22 (1997), EN 301 489-26 (2001-9), YD 1169.2-2001;

Applicable port: Signal and control line port;

Limits: CLASS B;

8/10/2019 zte1

21/113



The limits for conducted disturbances of the signal and control line port are shown as following.

Table 11 Limits for Conducted Disturbances of the Signal and Control Line Port

Voltage Limit (dBV) Current Limit (dBA)Frequency Range

(MHz)Quasi-Peak

Value

Average

Value

Quasi-Peak

ValueAverage Value

0.15 0.5 84 74 74 64 40 30 30 20

0.5 30 74 64 30 20

10. Harmonic current and flicker

Standard: IEC 61000-3-2 (2001-10); IEC 61000-3-3 (2001-01);

Applicable port: AC port.

2.2.3.3 Safety Indices

The safety indices comply with the requirements specified in IEC 60950-2001 Safety of

Information Technology Equipment.

1. Resistance of protective grounding conductor

Limit: The protective grounding resistance is less than 0.1.

2. Contact current and protective conductor current

Applicable port: AC port;

Limit: The contact current should be less than 3.5mA and the protective conduct current is less

than 5% of the input current.

3. Dielectric strength

Applicable port: AC power;

Limit: 1500VAC between primary circuit and ground; 3000VA between primary circuit and

secondary circuit; 500VDC between secondary circuit and group or between mutually

independent secondary circuits.

2.2.4 Performance Indices of Transmitter

The performance indices of the transmitter meet the requirements in TIA/EIA-97-D.

2.2.4.1 Frequency Tolerance

The frequency tolerance refers to the maximum difference between the actual CDMA Tx carrier

frequency and the specified CDMA Tx carrier frequency. The frequency of the system is less

than 5 108 (0.05ppm).

8/10/2019 zte1

22/113



The modulation modes used are QPSK (Quadrature Phase Shift Keying) and OQPSK (Offset

Quadrature Phase Shift Keying). QPSK and OQPSK are binary quadrature modulation modes.

The QPSK modulation is used for forward transmission in the transceiver, while the OQPSK

modulation is used for reverse receiving.

1. Synchronization and timing

1) Pilot time tolerance

The pilot time alignment error should be less than 3 s and the maximum error should be less

than 10 s.

For base stations supporting multiple simultaneous CDMA Channels, the pilot time tolerance of

all CDMA Channels radiated by a base station shall be within 1 s of each other.

2) Phase tolerance from pilot channel to code division channel

The phase differences between the Pilot Channel and all other code channels sharing the same

Forward CDMA Channel should not exceed 0.05 radians.

2. Waveform quality

The waveform quality is measured by determining the nominal correlation power between the

actual waveform and the ideal waveform. The cross correlation coefficient should be greater

than 0.95.

3. Power control sub-channel

The power control sub-channel test should guarantee the correct sensitivity, location, delay and

amplitude.

2.2.4.2 Requirements for RF Output Power

1. Total power

The total power refers to the total transmitting function in full load status. The total transmitting

power should be equal to the nominal power 2dB.

2. Pilot power

The ratio of the pilot channel power to the total power should be equal to the configurationvalue 0.5dB.

3. Code domain power

The code domain power on each inactive channel should be less than the total output power by

32dB or more.

2.2.4.3 Spurious Emission

1. Conducted spurious emission

8/10/2019 zte1

23/113



The conducted spurious emission refers to the outband frequency emission at the assigned

CDMA frequency, which is measured on the RF output of a BTS. The limits for the spurious

emission of the BTS transmitter of the CDMA system should meet the requirements of the

standard limit. Please refer to the following tables.

Table 12 Outband Spurious Requirements of IS97 BAND CLASS0 CDMA800 CELLULAR

Offset Center Frequency Range Requirements for Tx Level

750 kHz 1.98 MHz -45 dBc / 30 kHz

1.98 MHz 4.00 MHz

-60 dBc / 30 kHz; Pout 33 dBm

-27 dBm / 30 kHz; 28 dBm Pout

8/10/2019 zte1

24/113



6.5 10%

2.2.5.2 Sensitivity

Better than -127dBm.

When inputting the sensitivity level at the RF input (the interface between the shelf and the

antenna) of a BTS, the FER of the reverse traffic channel should be less than 1%.

2.2.5.3 Dynamic Range of the Receiver

-127dBm/1.23MHz~-65dBm/1.23MHz.

When inputting the dynamic range level of the receiver at the RF input (the interface between

the shelf and the antenna) of a BTS, the FER of the reverse traffic channel should be less than

1%.

2.2.5.4 Receiving Noise Figure of the Integrated Equipment

Should not be greater than 5dB.

2.2.5.5 Blocking

1. BAND CLASS0 CDMA 800M

Input the single-frequency interference of the offset center frequency at the RF input (the

interface between the shelf and the antenna) of the BTS. If the single-frequency interference is

at the offset center frequency 750kHz, the power of the input single-frequency interference is

higher than the output power of the mobile station simulator by 50dB; when the single-frequency interference is at the offset center frequency 900kHz, the power of the input single-

frequency interference is higher than the output power of the mobile station simulator by 87dB.

In the two cases, the REF of the reverse traffic channel should be less than 1.5%, and also the

closed loop power control is applied so that the output power of the mobile station simulator is

not greater than 3dB.


Input the single-frequency interference of the offset center frequency at the RF input (the

interface between the shelf and the antenna) of the BTS. If the single-frequency interference is

at the offset center frequency 1.25MHz, the power of the input single-frequency interference

is higher than the output power of the mobile station simulator by 80dB. In this case, the REFof the reverse traffic channel should be less than 1.5%, and also the closed loop power control

is applied so that the output power of the mobile station simulator is not greater than 3dB.

2.2.5.6 Intermodulation Spurious Response Fading


Input two single-frequency interferences of the offset center frequency at the RF input (the

interface between the shelf and the antenna) of the BTS. If the single-frequency interferences

8/10/2019 zte1

25/113



are at the offset center frequency +900kHz/+1700kHz, the power of the input single-frequency

interferences is higher than the output power of the mobile station simulator by 72dB; If the

single-frequency interferences are at the offset center frequency -900kHz/-1700kHz, the power

of the input single-frequency interferences is higher than the output power of the mobile station

simulator by 72dB. In the two cases, the REF of the reverse traffic channel should be less than

1.5%, and also the closed loop power control is applied so that the output power of the mobile

station simulator is not greater than 3dB.


Input two single-frequency interferences of the offset center frequency at the RF input (the

interface between the shelf and the antenna) of the BTS. If the single-frequency interferences

are at the offset center frequency +1.25MHz/+2.05MHz, the power of the input single-

frequency interferences is higher than the output power of the mobile station simulator by 70dB;

If the single-frequency interferences are at the offset center frequency -1.25MHz/-2.05MHz, the

power of the input single-frequency interferences is higher than the output power of the mobile

station simulator by 70dB. In the two cases, the REF of the reverse traffic channel should be

less than 1.5%, and also the closed loop power control is applied so that the output power of the

mobile station simulator is not greater than 3dB.

2.2.5.7 Conducted Spurious Emission

The conducted spurious emission should:

1. Be less than -80dBm when measured with a resolution bandwidth of 30kHz at the RF

input port of the BTS on the receiving band of the BTS receiver;


input port of the BTS on the operating band of the BTS transmitter;


input port of the BTS at other frequencies.

2.2.5.8 Radiated Spurious Emission

The radiated spurious emission targets at the integrated BTS equipment (the transmitter and the

receiver as well). The radiated spurious emission should be less than the level of the conductedspurious emission specified in the Section 2.2.4.3 in the chapter.

2.2.6 Clock Requirements

2.2.6.1 Technical Parameters of Micro-BTS Clock

The technical parameters should meet the following requirements:

Frequency reference: The frequency accuracy of 10MHz in locked GPS status should be

better than an accuracy of 10-11, and be better than 10-10in holdover status.

8/10/2019 zte1

26/113



Temperature characteristic:

8/10/2019 zte1

27/113


3 HARDWARE OF MICRO BASE TRANSCEIVERSTATIONS

3.1 Overview of Hardw are Structu re

3.1.1 Overview of Micro-BTS Hardware Structure

ZXCBTS CDMA micro-BTS (ultra-wide coverage micro BTS as well) is the radio part of the

Base Station Subsystem (BSS). A ZXCBTS CDMA micro-BTS completes radio transmission

of subscribers (mobile stations, that is, MSs for short) and implements control over radio

channels via an air interface (the Um interface). Furthermore, the micro-BTS also provides a

wired interface with the BSC. Cells covered by a ZXCBTS CDMA micro-BTS are of Omni

directional (Omni) or sector structure.

A ZXCBTS CDMA micro-BTS (ultra-wide coverage micro-BTS as well) is composed of the

following subsystems: Base band Digital Subsystem (BDS), Timing & Frequency Subsystem

(TFS), Radio Frequency Subsystem (RFS), power subsystem, lightning protection subsystem

and built-in 155M SDH optical transmission subsystem (optional).

The operational principles of the M800/M802 and M190/M191/M192 micro-BTS systems are

shown as following.

8/10/2019 zte1

28/113



155M

SDH(T150)

MDIV

MPA

MTRX

TXRX0

BDM

E1 to BSC

MLNA

MDUP

MLNA

ant0 ant1

RX1

Micro-BTS shelf

GPSTM

GPS

antenna Rx antenna Shared Tx/Rx antenna

STM-1

4 E1

Optional

module

Fig. 6 Logical Structure of Micro-BTS

The connection between a micro-BTS and a BSC is shown as following:

Fig. 7 Block Diagram of the Micro-BTS System

8/10/2019 zte1

29/113



The hardware photo of a micro-BTS is shown as following.

1 Baseband processing module, BDM board; 2 Timing & frequency module, GPSTM; 3 power, MPD; 4 diversity filter, MDIV; 5 Low-noise amplifier, MLNA; 6

High power amplifier, MPA; 7 Tx/Rx duplexer, MDUP; 8 power arrestor; 9 Antenna feeder arrestor; 10 E1 arrestor; 11 optical transmission module;

Fig. 8 Photo of a Micro-BTS

3.1.2 Overview of Remote Station Hardware Structure

ZXCBTS CDMA remote stations are structurally compatible with ZXCBTS

M800/M802/M190/M191/M192 micro-BTSs completely. A ZXCBTS CDMA remote station

does not have the TFS and BDS. To form a ZXCBTS CDMA remote station, just replace the

BDM with an RFM. The structure of a CDMA remote station is shown as following.

8/10/2019 zte1

30/113



RF Tx/Rx antenna

Remote station

Lightning protection unit

Remote Fiber

Module (RFM)

RFS (MTRX,

MPA, MLNA

and RFE)

Power

Macro-BTS

Micro-BTS

Fiber

Fig. 9 Structure of ZXCBTS CDMA Remote Station

3.1.3 Common Grounds and Major Differences between Micro-BTS andRemote Station in Hardware Structure

The ZXCBTS M800/M802/ M190/M191/M192 micro-BTS and the ZXCBTS R800/R802/

R190/R191/R192 remote station are of the same shelf structure. The replacement of somemodules in the shelf can implement mutual conversion between the micro-BTS system and the

remote station system, as shown in Fig.

and

.

The micro-BTS and the remote station have the same RF system, power system and antenna

feeder system. The micro-BTS has a Baseband Digital Module (BDM), the remote station does

not have BDM and Timing & Frequency Subsystem (MGPSTM) but has a transparent

transmission module (RFM.). Based on different bands of the RF system, micro-BTSs and

remote stations have the following types: 800MHz micro-BTS/remote station system and

1900MHz micro-BTS/remote station system. With respect to the shelf structure, the ZXCBTS

M800/M802/M190/M191/M192 micro-BTS and the ZXCBTS R800/R802/R190/R191/R192

remote station are of the same shelf structure. However, with consideration of heat dissipation,

three heat dissipation fans are added at the bottom of the shelf of the ZXCBTS M802/ M192micro-BTS and the ZXCBTSR802/R192 remote station to improve the operation stability of the

system. The micro-BTS series of products can provide the builtin SDH function, while the

remote stations do not support the function. There are not greater differences between 800MHz

and 1900MHz micro-BTS/remote station systems, so the 800MHz and 1900MHz systems will

not be differentiated in subsequent chapters and sections.

The operational principles of each subsystem will be detailed in the following paragraph.

8/10/2019 zte1

31/113



3.2 BDS

3.2.1 OverviewThe Baseband Digital Subsystem (BDS) of a micro-BTS is a digital board BDM (Baseband

Digital Module). The board also provides interfaces between the BDS and the TFS and RFS. A

remote station does not have the subsystem.

3.2.2 BDM

3.2.2.1 Overview

The Baseband Digital Subsystem (BDS) is a part that can reflect the CDMA features most

efficiently in a ZXCBTS CDMA micro-BTS. Many key CDMA technologies are applied to the

BDS, such as diversity technology, RAKE receiving, softer handoff and power control. Themajor functions of the BDS are to complete the modulation & demodulation of baseband

signals and to provide an interface with the RF part and an Abis interface with the BSC.

3.2.2.2 Functions

The Baseband Digital Module (BDM) is the core module of a ZXCBTS CDMA micro-BTS,

which completes the modulation & demodulation of baseband data, signaling processing,

resources management and operation & maintenance.

The BDM receives digital sampling signals of the Rx antenna from the RFS, conducts

demodulation and then sends service/signaling frames to the BSC via E1 links. The BDM also

performs demodulation of service/signaling frames from the BSC and sends the data to theRadio Frequency Subsystem (RFS). The BDM board consists of a CSM5000 chip and three

reserved CSM5000 sub-board interfaces. The BDM board can support a maximum of three

CSM5000 chips. Each CSM5000 chip can independently implement the

modulation/demodulation of 64 forward channels and 32 reverse channels. In addition, the

BDM can complete the processing of the Abis interface signaling and the centralized monitor

and maintenance of the entire ZXCBTS CDMA micro-BTS.

3.3 RFS

3.3.1 OverviewThe RFS (Radio Frequency Subsystem) is an important part of a micro-BTS or a remote station.

Its functions are as follows: Providing an air interface via the antenna, implementing an

interface with the BDS via RFCM, completing the modulation transmission and demodulation

receiving of CDMA signals and implementing detection, monitor, configuration and control

functions.

8/10/2019 zte1

32/113



RFS BDS

Antenna 0 Antenna 1

Fig. 10 Position of RFS in a CDMA Micro-BTS

3.3.2 Block Diagram

The block diagram of the RFS of a micro-BTS is shown as following. At present, the subsystem

only supports the configurations of single-carrier single-sector, two-carrier two-sectors (for

example, the second carrier is a remote station) and single-carrier two-sector. Compared with

the single-carrier single-sector configuration, the hardware configuration of a dual-carrier

micro-BTS is a bit different in the two-carrier two-sector or single-carrier two-sector

configuration, since the MDIV is not needed. Normally, the RFS of a micro-BTS is composed

of modules such as MTRX (Micro Transmitter & Receiver), MPA (Micro Power Amplifier),

MDUP (Duplex), MDIV (Diversity), MLNA (Micro Low Noise Amplifier) and arrestor.

8/10/2019 zte1

33/113



TX

MPA

RX0

RFCM

MDUP MDIV

BDS

RFS

Antenna 0 Antenna 1

Note: The TX\RX0\RX1 boards comprise

the MTRX module

MLNA

MLNA

RX1

Fig. 11 Single-Carrier Single-Sector RFS Subsystem

8/10/2019 zte1

34/113



Antenna 0

TX

MPA

RX0 RX1

RFCM

MDUP

BDM OIM

GPSTM

GPS

antenna

TX

MPA

RX0 RX1

RFCM

MDUP

RFS

RFM

Antenna

1

Micro-BTS shelfFiber

Remote station shelf

Interconnection cable

MLN

A

MLN

A

RFS

Note: The TX, RX0 and RX1 boards comprise an MTRX module.

Fig. 12 Two-Carrier Single-Sector RFS

8/10/2019 zte1

35/113



TX

M

PA

RX

0

RX

1

RFCM

BDM OIM

GPSTM

GPS

antenna

TX

MPA

RX

0

RX

1

RFCM

MDUP

RFS

RFM

Micro-BTS shelfFiber

Remote station shelf

RFS

MDUP

Antenna 0

MDUP

Antenna 1

MDUP

M

LNA

MLNA

MLNA

MLNA

Ant enna 0 Ant enna 1

Note: The TX, RX0 and RX1 boards comprise an MTRX module.

Fig. 13 Single-Carrier Two-Sector RFS

3.3.3 Features

1. The RFS implements the radio air interface of a micro-BTS/remote station;

2. Flexible configuration: Supporting multiple configurations such as single-carrier

single-sector, three-carrier single sector or single-carrier three-sector;

3. Perfect EMC&EMI design: In compliance with related international standards;

8/10/2019 zte1

36/113



4. Small size, compact structure and high reliability: Applicable to installation operation in

rigorous indoor and outdoor conditions.

3.3.4 Hardware Structure

The RFS is composed of the following modules: MTRX, MPA, MDUP, MDIV (not available

in dual-carrier configuration), MLNA and arrestor. The positions of the modules in a micro-

BTS are shown in the above figures.

3.3.5 MTRX

3.3.5.1 Overview

MTRX connects radio frequencies and baseband signals. An MTRX corresponds to a sector

and a carrier. The MTRX receives the master receiving and diversity receiving signals of twoRFEs of a sector, separately conducts down conversion and intermediate frequency filtering,

completes I/Q demodulation after AGC processing and converts the received RF modulation

signals into baseband I/Q signals. In the meantime, the MTRX also receives forward baseband

I/Q signals, conducts I/Q modulation and intermediate frequency filtering and converts them

into RF modulation signals by means of up conversion. In addition, the MTRX conducts power

control operation of the TPTL. Therefore, MTRX is the key to Tx/Rx link signal processing in

the RFS.

3.3.5.2 Functions

Basic functions of the MTRX are as follows:

1. Providing interfaces between baseband signals and the MPA and RFE modules,

transferring the Tx/Rx baseband data and transmitting the information about

configuration, control, status and alarm maintenance;

2. Forward link: Converts baseband digital signals to RF debugging signals;

3. Reverse link: Converts RF signals to baseband digital signals;

4. Completing power control and cell breathing of the system.

3.3.6 MPA Module

3.3.6.1 Overview

MPA is a very important module in the RFS. Its power determines the coverage of a BTS. The

major examination indices of a power amplifier are work efficiency, ACPR, gain flatness and

gain fluctuation.

8/10/2019 zte1

37/113



3.3.6.2 Functions

Functions of MPA:

1. Amplification of RF signals;

2. Detection of input, output and reverse output powers;

3. Temperature detection;

4. Generation and report of alarm signals.

The MPA (Micro Power Amplifier) receives forward Tx CDMA signals from the MTRX and

makes power amplification so that the RF signals can reach the necessary power value. After

the processing of the duplex filter at the RF front end, the signals will be emitted to the cells byan antenna to cover the corresponding areas. A CDMA system has some special requirements

for the MPA of a BTS, since the forward Tx CDMA signals are in QPSK modulation mode and

belong to non-constant envelope signals in linear modulation, and the peak-to-average ratio of

signals is relatively higher. To ensure a lower distortion of Tx signals and prevent spectrum

spread of the signals, the MPA should have certain linearity. In this system, the power

backoff technology, the feed-forward technology and the digital pre-distortion technology are

applied to guarantee the linearity of the MPA. The power amplifier is a high-temperature device

that has high requirement for heat dissipation. If the heat of the power amplifier cannot be

dissipated efficiently, the amplifier will be easily damaged due to operation in a high-

temperature environment for a long period of time. To better protect the power amplifier and

make fault diagnosis efficiently, related software is used to configure overtemperature alarm,

standing wave alarm, overpower alarm and device failure alarm/switchoff.

Overtemperature alarm: If the MCU in the power amplifier detects that the operating

temperature of the amplifier is higher than the preset value, it will switch off the bias voltage of

the RF signals and amplifier tube and will switch on the amplifier again when the temperature

drops to the specified value.

Standing wave alarm: If the RFE cable is not connected correctly, the power of the amplifier

cannot be transmitted into air completely and a standing wave alarm will be generated to switch

off the amplifier. If a standing wave alarm is generated, manual intervention is needed to restart

the amplifier.

Overpower alarm: If the output power of the power amplifier reaches rated power + 3dB, an

overpower alarm will be generated to switch off the amplifier. Then the input power will be

detected. If the input power is less than -9dBm, the amplifier will be switched on to restart work

automatically.

Device failure alarm: If the gain of the power amplifier changes by 6dB, a device failure alarm

will be generated to switch off the amplifier. Manual intervention is needed to restart the

amplifier.

8/10/2019 zte1

38/113



3.3.7 MLNA Module

3.3.7.1 OverviewThe MLNA board is an independent module in a micro-BTS system. Normally, each micro-

BTS system has two MLNA boards connected to MDUP and MDIV separately to implement

low-noise amplification of weak signals received by the antenna.

3.3.7.2 Functions

Functions of MLNA board:

Low-noise amplification of small signals received by the antenna;

Power distribution of received signals after low-noise amplification;

Status monitor of the low-noise amplifier.

3.3.8 MDUP Module

3.3.8.1 Overview

The RFE-MDUP module is an RF front-end RFE module of a micro-BTS, which is an

important module completing the transmitting and receiving functions simultaneously in the

RFE. With the application of this module, an antenna can complete the transmitting and

receiving of RF signals. Thus, the costs are reduced greatly. The module is a frequently used

part in frequency division duplexer systems.

3.3.8.2 Functions

Functions of RFE-MDUP:

Filtering small signals received by the antenna;

Tx/Rx duplex

Filtering forward Tx power signals.

3.3.9 MDIV Module

3.3.9.1 OverviewThe RFE-MDIV module is an RF front-end RFE module in a micro-BTS system, which is an

important module completing the diversity receiving function in the RFE.

3.3.9.2 Functions

The RFE-MDIV is used to filter small signals received by the antenna.

8/10/2019 zte1

39/113



3.4 TFS

3.4.1 OverviewThe Timing & Frequency Subsystem (TFS) provides the BDS of a micro-BTS with clocks (that

is, 16CHIP and PP2S) necessary for the system and meanwhile provides the TOD (Time Of

Date) message. In a micro-BTS, the TFS provides clocks for the BDM board and meanwhile

provides 10MHz sinusoidal signals for the RFS. The clock of a remote station is optically

transmitted to the RFM board of the remote station via an OIM sub-board inserted on the BDM.

The RFM board needs a phase lock loop to convert the 16CHIP digital clock transmitted via

fiber to the 12M analog signal, in order to provide the RF part with a local oscillation signal.

For details, please refer to Section 3.5.5, RFM Module, and Section 3.5.6, OIM Module, in

this manual.

3.4.2 Block Diagram

The TFS of a micro-BTS is an MGPSTM board. The position of MGPSTM in a micro-BTS is

shown as following.

BSC, macro-BTS or

micro-BTS

BDS(BDM) RFS (TRX, HPA,

LNA, RFE)

MGPSTMPower

GPS RF Tx/Rx antenna feeder and power

lightning p rotection

E1 (four)

Micro-BTS

GPS Rx antenna RF Tx/Rx antenna

Fig. 14 Position of MGPSTM in a Micro-BTS

In a micro-BTS system, MGPSTM provides the BDS (physically, the BDM board) and RFS

(physically, MTRX, HPA, LNA and RFE) with timing moment reference and frequency

reference signals. The timing moment reference signal is as follows: PP2S (even seconds) and

19.6608MHz, and the frequency reference signal is 10MHz. In addition, MGPSTM provides

the BDM with a TOD interface and a control interface.

8/10/2019 zte1

40/113



3.4.3 Features

TFS stands for Timing & Frequency Subsystem. In an MBTS (Micro Base Transceiver Station),

in addition to the timing reference PP2S, system clock and the TOD message, the TFS alsoprovides the 12MHz reference clock. The TFS provides the synchronous clock and frequency

reference for the radio side of the entire CDMA system and also provides the standard time for

the entire system.

The TFS requires a higher reliability, which is the clock pivot to the entire system. It has greater

influence upon the reliability and stability of the system.


Physically, the TFS of a micro-BTS is an MGPSTM board.

The input and output interfaces of the TFS are connected to the BDM via a cable with DB25connector.

Output interfaces of MGPSTM:

1. One 16CHIP signal, one PP2S signal, with the signal level of PECL: Connected to the

BDM module via a DB25 cable;

2. One 10MHz signal, with the signal level of SINE signal: Connected to the BDM

module via a coaxial cable;

3. One TOD message, with RS232 level: Connected to the BDM module via a DB25 cable.

Input signals of MGPSTM:

1. GPS antenna, receiving GPS satellite signals: transmitted on a shielded coaxial cable;

2. One TOD message, with RS232 level: Connected to the BDM module via a DB25 cable;

3. +12V and 5V power supplies.

3.4.5 MGPSTM

3.4.5.1 Overview

In a CDMA mobile communications system, synchronization contains transmission

synchronization and radio synchronization. Normally, the transmission synchronization is in

master/slave mode, while the radio synchronization is in GPS synchronization mode in a

CDMA system. That is to say, all radio interfaces of the entire cellular system are synchronized

to the same standard moment. The standard moment is provided by the GPS system, which is

synchronous with the UTC (Universal Time Coordinated).

8/10/2019 zte1

41/113



In the ZTE CDMA system, the synchronization timing scheme has the following requirement:

The MBTS and BSC are synchronized to the standard moment signal provided by the GPS. The

MPSTM is just such a module that can provide an MBTS with the standard moment signal and

related system references, which is the key module in the CDMA system.

3.4.5.2 Functions

The MGPSTM provides the BDS of a micro-BTS with the clock necessary for the system, that

is, 16CHIP and PP2S. In a micro-BTS, it provides the BDM board with the 16chip and pp2s

clocks and the TOD message. Furthermore, the MGPSTM also provides the RFS with 10MHz

sine signals. For the clock extraction of a remote station, please refer to Section 3.3.4 in the

manual.

3.5 Transmiss ion Subsys tem

3.5.1 Overview

SDH (Synchronous Digital Hierarchy) is a complete set of standard digital transmission

hierarchy that can implement synchronous digital transmission, multiplexing and cross-

connection. SDH is used to transfer different types of payloads after adaptation on a physical

transmission network. SDH is a standard transmission system based on (PDH (Plesiochronous

Digital Hierarchy), and its basic structure unit is STM.

An STM is an information structure composed of payload Section OverHead (SOH) and AU

pointer, with a repetition period of 125s. Such information suits for serial transmission on a

selected medium at a rate synchronous with the network. The rate of the STM-1 module signal

is 155520kbps. The signal of higher-order STM-N module is composed of N STM-1 signals

cascaded in synchronous duplex mode.

The built-in SDH module of a micro-BTS (Unitrans ZXSM T150) is an SDH STM-1 product,

with a rate of 155520kbps. Unitrans ZXSM T150 outdoor compact synchronous digital

transmission equipment (hereinafter called ZXSM T150 for short) is the latest STM-1 outdoor

compact synchronous digital transmission equipment developed by ZTE CORPORATION,

which is a kind of SDH equipment specially developed by mobile, CDMA and 3G outdoor BTS

application environments. The equipment provides standard line interfaces (standard E1

interfaces). The equipment can serve as independent equipment to implement networking via

standard SDH 155Mbps optical interfaces or can serve as the corollary equipment of standard

SDH or PDH series of equipment to complete networking. Furthermore, the equipment canmeet the requirements for 2Mbps communication services of Metropolitan Area Networks

(MANs), railway communication networks, military communication networks, financial data

communication networks, transportation communication networks and electric power

communication networks.

With high-integrity modular design and small size, the ZXSM T150 equipment supports

networking in two STM-1 optical directions and also can implement interconnection and

interworking with the existing ZTE SDH equipment. Multiple installation and power supply

modes can be provided for the ZXSM T150 equipment, which features perfect function,

8/10/2019 zte1

42/113



flexible networking, convenient installation and low cost. Therefore, in the mobile transmission

field, the ZXSM T150 equipment provides users with an economic, efficient and rapid radio

transmission means.

3.5.2 Block Diagram

ZXSM T150 is a board integrated with all functions, which can be functionally divided into the

following units: Net Control & Process Unit (NCPU), Clock Unit (CU), Optical Unit (OU),

Cross Switch Unit (CSU), Tributary Unit (TU), CPU and Power Unit (PU). The relation

between the units in the system and the bus connection relation are shown as following.

ADD&DATA

OU

O1

O2

5V&3.3V

AD22

CSU

TU

CU

PUNCPU and CPU

D1

D2

5V&3.3VPGND

IN

ECC

S1 19.44M

DD11 4E1

Fig. 15 Units in the ZXSM T150 System

Description:

O1 and O2: Respectively indicate optical interface 1 and optical interface 2;

D1 and D2: Are VC-4 buses to the CSU, which are from optical interface 1 and optical

interface 2 separately

DD11: Drop bus from the CSU to the TU, two groups in total;

AD22: Add bus from the TU to the CSU, two groups in total;;

4E1: 4 E1 interfaces.

3.5.3 Features

Features of the subsystem include:

1. Small size and powerful functions

8/10/2019 zte1

43/113



The ZXSM T150 equipment is a board integrated with all functions. The board is composed of

the following units: NCPU, OU, CSU, TU, CU and PU. The equipment features high integrity

and small size. Functionally, the equipment is integrated with two STM-1 optical interfaces that

can directly add/drop four E1s. Furthermore, the equipment also supports the line and ring

networking modes and the double-fiber uni-directional path protection ring service. The ZXSM

T150 equipment does not provide any BITS interface and orderwire telephone.

2. Standard SDH STM-1 optical interfaces: The equipment can support networking

independently or cooperate with other SDH equipment to implement networking.

In addition to standard E1 interfaces, the ZXSM T150 equipment also provides standard SDH

155Mbps optical interfaces. Based on the detailed situations, ZXSM T150 can be used to

establish a transmission network independently or can cooperate with other standard SDH

equipment to implement networking, in order to expand the interface access capability of the

SDH equipment. The networking mode by using the flexible configuration capability of the

ZXSM T150 equipment saves users investment and also reduces network complexity and

facilitates maintenance.

3. Direct fiber networking and ring network protection

The ZXSM T150 equipment supports direct networking by using its 155M optical interfaces

and the ring network protection function of SDH, which can greatly increase the access

capacity and improve the network security.

4. Suitable for rigorous environments

During the design of the ZXSM T150 equipment, we strictly follow the related ITU-T

recommendations and the communications industry standards of China. With full consideration

that the equipment may operate in rigorous environments, we select the best process structure,circuit design scheme and quality lightning-protection devices to enhance the anti-interference

and lightning-protection capability of the equipment and also to resist severe interferences of

high voltage and surge. With full airtight and waterproof design and advanced process

techniques to guarantee components, cables (fiber cables) of the ZXSM T150 equipment can

work reliably and stably in rigorous outdoor environmental conditions. The equipment suits for

rigorous high-temperature and high-humidity environments: It can work normally at -35C

~+55C, with a relative humidity of 5%~100%.

5. Efficient unified Network Management System (NMS) and flexibly networking,

management and configuration

The ZXSM T150 equipment and other standard SDH equipment receive the unifiedmanagement of the ZXONM E100 and ZXONM E300 network management systems. The

powerful network management capability of the ZXONM E100 and ZXONM E300 network

management systems guarantees the reliable operation and management of the ZXSM T150

equipment.

6. Flexible power design

A user can select the power supply for the ZXSM T150 equipment according to the power

supply conditions in the equipment room. The user can select +24V or -48V DC power supply.

8/10/2019 zte1

44/113



The -48V or +24V power input is in 1+1 protection mode to improve reliability of the

equipment.


The SDH subsystem is composed of a board, and its block diagram is shown in

. The subsystem can be functionally divided into the following units: NCPU, CPU

unit, CU, OU, CSU, TU and PU.

1. NCPU and CPU

NCPU and CPU are the control core of ZXSM T150, which executes commands from the NMS,

completes realtime clock management, reports information to the NMS in real time, conducts

direct configuration and management of each unit and implements remote download of the

FPGA program.

2. CU

The CU implements network synchronization and ensures that the clock, frequency and phase

of each NE and node in networking are controlled within the preset tolerance range to avoid

transmission loss caused by clock de-synchronization. The clock unit consists of: reference

selection, phase detection, PLL, D/A conversion and alarm detection. The CU finally completes

fast pull-in, normal trace, holdover and free run and uses the S1 byte to implement SSM

functions.

3. OU

The OU completes optical/electrical conversion, clock restoration, data regeneration,

serial/parallel conversion, overhead processing and line clock conversion. Where, the overheadprocessing refers to: In addition to use in the local unit, the overhead bytes should also extract

and insert D1~D3 andS1 and support the use in NCPU and CU, and the transparent

transmission processing is made for other bytes. Finally, the VC-4 sends them to the CU.

4. CSU

After the processing of the TU pointer, the two groups of VC-4 buses from the OU enter the

FPGA to complete the transparent transmission and add/drop functions.

5. TU

The TU implements E1 payload mapping/de-mapping of specified timeslots and mapping path,

adaptation and alarm processing based on ITU-T recommendations. The unit also completes

AIS detection and path protection switch and implements framing of the first and second E1s.

Set DIP switches to complete fixed configuration and ECC conversion. The 2M tributary unit

guarantees the 2M interface features and error performances.

6. PU

The PU sends the input -48V/24V DC power to the DC-DC module for conversion after surge

protection, DC filtering and reverse connection protection, and then outputs +5V and + 3.3V

powers. Then, the PU sends the power to other elements of the board after filtering to provide

stable and reliable power for all elements.

8/10/2019 zte1

45/113



3.5.5 RFM

3.5.5.1 OverviewThe RFM module is a transmission module between a macro BTS/micro BTS and a remote

station, which is composed of an RFM module and installed on a remote station. The RFM is

used in conjunction with the OIM on the micro BTS or the LFM on the macro BTS to transmit

baseband data and system signaling.

The module provides a pair of optical interfaces for connection with the LFM or OIM and

transparently transmits the sector signals of the remote station. Based on the different

transmission capabilities (15km and 40km) supported by the optical/electrical conversion

device in the RFM, the RFM is divided into two types: 15km RFM and 40km RFM. If the

distance from the remote station to the micro BTS (macro BTS) is less than 15km, the 15km

optical module is used; if the distance from the remote station to the micro BTS (macro BTS) isgreater than 15km, the 40km optical module is used.

The power used for the module involves digital 5VDC, digital 3.3VDC and analog +12VDC.

To guarantee simultaneous power-on, electronic switches are used to implement the function.

The module is powered on only when 3.3V and 5V are available.

The power module supplies the digital 5VDC power for the drive chip, optical module and the

PLL chip. The power module supplies the 3.3VDC power for the multiplex/demultiplex chip

and the CPLD chip. The analog 12VDC power is supplied for analog devices in the PLL circuit.

The total power consumption of the module is about 4W.

3.5.5.2 Functions

Functions of RFM:

The RFM is used to transmit CDMA baseband signals and system signaling. Connected

to the LFM module on a macro BTS, the RFM can form a fiber remote station solution

of the macro BTS; while connected to the OIM on a micro BTS, the RFM can form a

fiber remote station solution of the micro BTS.

The RFM restores the 16chip digital clock from the data bit streams on the fiber, outputs

the 12MHz (in case of 1.9G remote station) or 10MHz analog signal (in case of 800M

remote station) by means of a PLL and sends the signal to the MTRX to serve as the

input of the local oscillation generation circuit.

The module measures the transmission delay between the LFM (OIM) and the remote

station and reports it to the RFCM via an IIC device.

Furthermore, the module also monitors the temperature, humidity and door control

alarms of the remote station and reports the alarms to the RFCM via the I2C device.

8/10/2019 zte1

46/113



3.5.6 OIM

3.5.6.1 OverviewOIM is a sub-board of the BDM, which provides all optical/electrical conversion channels

exchanging data between the BDS and RFS of a BTS.

3.5.6.2 Functions

Functions of OIM:

1. Multiplexing the forward 16 channels of parallel data of the BDM into a pair of

differential signals;

2. Converting the multiplexed forward data into optical signals and sending the signals to

the RFM;

3. Converting the reverse data optical signals from the RFM into differential electrical

signals;

4. Demultiplexing the reverse data into 16 channels of parallel data and sending the data to

the BDM;

5. Reporting the link status to the BDM.

3.6 Power Subsys tem

3.6.1 Overview

The power subsystem supplies power for modules in a micro-BTS/remote station system.

3.6.2 Block Diagram

The block diagram of the power subsystem is shown in the following figures.

8/10/2019 zte1

47/113



27V

12V

-12V

UART

IIC

220VAC

Inputprotection

interference

suppression

Rectificationand

filteringsoftstartup

Control

circuit

Heater

Masterconverter

Linearvoltage

stabilization

Monitor

Fig. 16 Block Diagram of the Power Subsystem (220V AC input)

27V

12V

-12V

UART

IIC

-48VDC

Inputprotection

in

terference

su

ppression

Filteringsoft

startup

Control

circuit

Masterconverter

Lin

earvoltage

stabilization

Monitor

Fig. 17 Block Diagram of the Power Subsystem (-48V DC input)

3.6.3 Features

The power subsystem transforms the 220V AC or -48V DC power into appropriate voltages to

supply powers for modules in the micro-BTS/remote station system.

8/10/2019 zte1

48/113



In addition, the power subsystem controls the switch of the heater in the micro-BTS/remote

station system to stabilize the internal environment in the system.

Furthermore, the power distribution module also supports power monitor.

8/10/2019 zte1

49/113


4 SOFTWARE OF MICRO BASE TRANSCEIVERSTATIONS

4.1 Overview of Micro -BTS Software

The software of the ZXCBTS CDMA micro-BTS/remote station system (V5.4) consists of two

parts: BDM software and MTRX software. The BDM software resides on the BDM of a micro-

BTS. The same system software is used for 800MHz and 1900MHz micro-BTSs. However, no

BDM system software resides on remote stations. The BDM software cooperates with the

hardware of the micro-BTS system to complete the following functions: baseband

modulation/demodulation, radio channel management, control channel signaling processing,

monitor of external subsystems (such as the environmental/power/clock/RF subsystems),

operation & maintenance management of performance statistics/signaling trace/signaling

statistics/alarm processing and system functions such as software support for operation

support/system configuration/system control/external communications/software download. For

the details of the BDM software, please refer to Section 4.2.

The MTRX software resides on the MTRX module of micro-BTS/remote stations, which

controls, collects and reports the operation information about MPD/HPA, RF links and

peripheral environmental information devices. The MTRX software, controlled by related

processes in the BDM software via signaling, completes the following functions: power-on,

automatic calibration, collecting information and reporting to the BDM, monitoring

environmental information about door control, temperature/humidity/voltage and reporting it to

the BDM, conducting man-machine operations of micro-BTS/remote station equipment such as

MTRX/HPA/heater/fan, returning HPA/MTRX/MPD diagnosis test information of the micro-

BTS/remote station to the BDM and downloading MTRX software. For details of the MTRX

software, please refer to Section 4.3.

4.2 BDM Software

The system software of ZXCBTS CDMA micro-BTS and remote station system resides on the

BDM module of the micro-BTS (the same system software is used for 800MHz and 1900MHz

micro-BTSs, while no system software resides on the remote station). The system is

functionally composed of the following five subsystems: OSS (Operating System Subsystem),

SPS (Service Processing Subsystem), OMS (Operation and Maintenance Subsystem), DBS

(Database Subsystem) and CES (Channel Element Subsystem). The modules in the subsystems

8/10/2019 zte1

50/113



cooperate with each other to complete different functions of the system. The structure is shown

as following.

Fig. 18 General Structure of the Software System

4.2.1 OSS

4.2.1.1 Functions

The OSS encapsulates the running environment of the system, controls the resident hardware

modules and provides communications capabilities for the software subsystems running on the

hardware modules. The OSS manages the most important hardware resource (that is, processor),

provides operation support for execution of applications, isolates the applications from the

actual hardware environment and provides an application execution environment unrelated to

the actual hardware environment. In addition to communications and system control, the OSSprovides the most essential functions as follows: task scheduling of the pSOS system,

encapsulating system function invocation provided by the pSOS operating system into

processes, providing transparent interfaces for access to the bottom-layer hardware and

scheduling processes according to the current events and the messages transferred among

different processes. The encapsulation capability of the OSS guarantees perfect hierarchy

among the processes so that the application software can still support better maintainability and

portability even if the software/hardware platform of the system changes.

4.2.1.2 Structure

The OSS is a software subsystem based on the commercial embedded realtime operating systempSOS. The OSS is located between all other subsystems of the background software and the

resident hardware platform, which isolates other subsystems from the actual hardware

environment, provides a virtual machine platform to support the running of the subsystems and

bears the running of the application layer software.

The position of the OSS in the entire system software and its structure are shown as following.

8/10/2019 zte1

51/113



Hardware platform

BSP

pSOS realtime multi-task operating system

OSSRunning support

OS

zte1

Documents