01 system description of bts3002c

8/13/2019 01 System Description of BTS3002C

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Huawei Technologies Proprietary

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Chapter 1 Introduction.................................................................................................................. 1-1Chapter 2 Features........................................................................................................................ 2-1

2.1 Product Key Technology....................................................................................................2-12.2 Environment Adaptability ................................................................................................... 2-12.3 O&M Function.................................................................................................................... 2-2

Chapter 3 Product Description .................................................................................................... 3-13.1 Product Appearance.......................................................................................................... 3-13.2 Hardware Structure............................................................................................................ 3-13.3 System Architecture........................................................................................................... 3-2

3.3.1 Main Control Subsystem......................................................................................... 3-23.3.2 Transceiver Subsystem........................................................................................... 3-43.3.3 Heating Subsystem................................................................................................. 3-83.3.4 Power Supply Subsystem ....................................................................................... 3-8

Chapter 4 Functions...................................................................................................................... 4-14.1 Basic Functions.................................................................................................................. 4-14.2 Digital Trunking Function................................................................................................... 4-2

4.2.1 VGCS ...................................................................................................................... 4-24.2.2 VBS ......................................................................................................................... 4-24.2.3 Fast Group Call Setup............................................................................................. 4-24.2.4 Late Entry................................................................................................................ 4-24.2.5 eMLPP..................................................................................................................... 4-24.2.6 Late Group Channel Assignment............................................................................ 4-34.2.7 Assigned Channel Supervision ............................................................................... 4-34.2.8 Voice Private Call Service....................................................................................... 4-34.2.9 PTT Preemption...................................................................................................... 4-34.2.10 Talker Identification............................................................................................... 4-34.2.11 Half Rate Group Call ............................................................................................. 4-34.2.12 Late A Interface CIC Assignment.......................................................................... 4-34.2.13 800M Band Supported and 800M Hopping........................................................... 4-44.2.14 Reserved Channel ................................................................................................ 4-44.2.15 Trunking Emergency Call...................................................................................... 4-44.2.16 Fall Back................................................................................................................ 4-54.2.17 Stand Alone........................................................................................................... 4-5

4.3 Networking Functions ........................................................................................................ 4-54.3.1 E1 Networking......................................................................................................... 4-54.3.2 SDH Networking...................................................................................................... 4-6

Table of Contents

System DescriptioniSite BTS3002C Integrated Mini BTS Table of Contents


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System DescriptioniSite BTS3002C Integrated Mini BTS


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4.3.3 Combined Networking............................................................................................. 4-74.4 Radio Network Functions................................................................................................... 4-7

4.4.1 Diversity Receiving.................................................................................................. 4-74.4.2 RF Hopping ............................................................................................................. 4-7

4.4.3 Power Control.......................................................................................................... 4-84.4.4 Uplink Frequency Scanning .................................................................................... 4-8

Chapter 5 O&M System................................................................................................................. 5-15.1 O&M Functions.................................................................................................................. 5-1

5.1.1 Security Management ............................................................................................. 5-15.1.2 Alarm Management................................................................................................. 5-15.1.3 Maintenance Management...................................................................................... 5-15.1.4 Performance Measurement and Test ..................................................................... 5-2

5.2 O&M Structure ................................................................................................................... 5-25.2.1 Overview ................................................................................................................. 5-25.2.2 Local Maintenance.................................................................................................. 5-35.2.3 Remote Maintenance.............................................................................................. 5-4

Chapter 6 Reliability Design......................................................................................................... 6-16.1 System Reliability Design .................................................................................................. 6-1

6.1.1 System Fault Monitoring and Handling................................................................... 6-16.1.2 Derate Design ......................................................................................................... 6-16.1.3 Temperature Design ............................................................................................... 6-16.1.4 Electromagnetic Compatibility Design .................................................................... 6-16.1.5 Reliability Design for Input Voltage......................................................................... 6-26.1.6 Reliability Design for Fault Detection...................................................................... 6-2

6.2 Hardware Reliability Design............................................................................................... 6-26.2.1 Inverse Connection Indication................................................................................. 6-26.2.2 Avoiding Misplugging for Cable Connectors ........................................................... 6-26.2.3 Signal Protection..................................................................................................... 6-26.2.4 Reliability Design for RF Cables ............................................................................. 6-3

6.3 Software Reliability Design ................................................................................................ 6-36.3.1 Fault Isolation Feature ............................................................................................ 6-36.3.2 Operational Security................................................................................................ 6-3

Chapter 7 Technical Indices......................................................................................................... 7-1

7.1 Overall Engineering Indices............................................................................................... 7-17.2 Overall Performance Indices ............................................................................................. 7-37.3 External Physical Interfaces .............................................................................................. 7-4


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 1 Introduction


1-1

Chapter 1 Introduction

This document is prepared to lay a foundation for understanding Huawei Base

Transceiver Station 3002C (BTS3002C). Huawei BTS3002C not only fulfils the

technical parameters indicated in the "PHASE 2/PHASE 2+" series of

recommendations under the responsibility of the GSM Technical Committee of the

European Telecommunication Standards Institute (ETSI), but also provides the digital

trunking function.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 2 Features


2-1

Chapter 2 Features

BTS3002C is the 2nd

generation of Huawei mini BTS, whose performance and feature

design are much better than the common micro-cells.

2.1 Product Key Technology

It is an outdoor mini BTS with small size and light weight, so it involves low cost

and can greatly save construction investment.

Its Max. transmission power is 20W and it supports dual-TS wide coverage.

It supports single and dual carrier configuration, and adopts modular RF structure. With imbedded optical transmission, it supports SDH loop networking

self-protection and provides one channel of dedicated E1 to other devices.

It supports Abis transmission bypass and greatly enhances networking stability.

It supports TS frequency hopping and diversity receiving with high receiving

sensitivity.

It supports BTS power-off alarm report when UPS and battery are not utilized

(from the alarm report, transmission disconnection and BTS power-off can be

differentiated).

It supports GPRS, supports CS3/CS4 radio channel-coding methods. So it can

realize the smooth migration from 2G to 2.5G.

It supports uplink frequency scanning function for network optimization.

2.2 Environment Adaptability

BTS3002C is an outdoor mini BTS with strong environment adaptability.

Fully obturated and integrated architecture. It has strong capability for resisting

water, dust, moist, salt (acid) smog, mould and sunshine radiation.

Wide voltage range. It can work normally within the voltage range 150 ~ 300V AC

and -40V DC ~ -60V DC.

Flexible working temperature range. When the AC/DC PSU is adopted,

BTS3002C can work normally under the temperature -40C ~ +55C

(environment temperature). When the DC/DC PSU is adopted, BTS3002C can

work normally under the temperature -20C ~ +55C (environment temperature).

Strong lightning protection capability. It is designed with imbedded lightning

protection board and attached power lightning protection box.

Flexible installation mode. It can be installed on the wall, mast, tower or telegraph

pole etc.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 2 Features


2-2

Battery power supply supported. Battery power supply can prolong power supply

duration when public power supply is halted.

2.3 O&M FunctionBTS3002C can perform the following O&M functions: software downloading, BTS

object attribute configuration management, equipment management and running state

monitoring.

Local end maintenance. It provides Man Machine Interface (MMI), and

implements maintenance, monitoring and management to all objects of the BTS

through the local maintenance console.

Remote end maintenance. O&M network is built up in the GSM system. The

authorized user can use any workstation in the network via the remote

maintenance console to perform remote O&M to BTS NEs in the system.

System state monitoring. It provides system running indices indication, resource

state indication, local cell configuration and state indication.

Security management. It provides user login authentication, command authority

restriction, unsecured operation indication and user group management.

Test, including function self-test and loop test.

Office monitoring. It provides data collecting and transmission channels for room

monitoring equipment to ensure unattended BTS with centralized monitoring.

Upgrading. It automatically checks the system for upgrading, system upgrading

can be performed via remote loading and the system can be restored to itsprevious version if system upgrading fails.

1-minute start-up: 1-minute start-up function greatly facilitates routine

maintenance of the equipment.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 3 Product Description


3-1

Chapter 3 Product Description

3.1 Product Appearance

BTS3002C is designed according to IEC297 standards.

Size: Height%Width%Depth = 700mm%460mm%360mm

The appearance is shown in Figure 3-1.

Figure 3-1 BTS3002C appearance

3.2 Hardware Structure

BTS3002C is composed of 4 units, 1 Main Control Unit (MCU), 2 Digital RF Unit (DRU)

and 1 Power Supply Unit (PSU), as shown in Figure 3-2.

PSU provides power supply to the system and there is a power supply module in it.

DRU provides the receiving and transmitting of carrier and baseband processing

function. It is composed of iSite TRansceiver Unit (ITRU), iSite Power Amplifier

Unit (IPAU), iSite Power Filter Unit (IPFU), iSite Duplexer Filter Unit (IDFU) and

heating board.


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MCU provides interfaces for O&M and transmission and is composed of iSite

Operation and Maintenance Unit (IOMU), iSite Access SDH (IASU), iSite

LightningProof Unit (ILPU) and heating board.

PSU DRU MCU DRU

Figure 3-2 BTS3002C under full configuration

3.3 System Architecture

BTS3002C is composed of 5 subsystems, power supply subsystem, main control

subsystem, transceiver subsystem, antenna and feeder subsystem and heating

subsystem, as shown in Figure 3-3.

IOMU IBBU

ILPU

Heating subsystem

Power supply

subsystem

Antenna

andfeedersub

system

Um

IPAUE1

220VAC

BTS3002C

Abis

MMI

IASU

Tx

Rx

ITRU

Transceiver subsystemMain control subsystem

E1

SDH

ILPU: LightningProof Unit IASU: iSite Access SDH IBBU: iSite BaseBand UnitITRU: iSite Operation and

Maintenance Unit

IOMU: iSite Operation and

Maintenance Unit

IPAU: iSite Power

Amplifier UnitFigure 3-3 BTS3002C system architecture

3.3.1 Main Control Subsystem

Main control subsystem is composed of IOMU, IASU, ILPU and the backplane IBMU

(iSite BTS3002C Motherboard Unit). It provides the following functions:

Provides periodic alignment signal.

Provides communication with O&M.


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Provides basic clocks to other subsystems and modules.

Implements conversion between SDH and E1.

Signal lightning protection function.

Signaling processing and resource management.

I. Operation and Maintenance Unit

IOMU is the interface and control unit of BTS3002C and integrates the following 4

functions: O&M function, BTS clock source function, BTS transmission interface

function and O&M cavity interface function.

O&M module accomplishes the O&M of the whole BTS.

BTS clock module provides reference clock signals to BTS transmission interface

module, O&M module and DRU.

BTS transmission interface module provides necessary timing calibration signal toBTS clock module and OML (Operation & Maintenance Link) and HDLC (HDLC,

High-speed Digital Link Channel) to O&M module.

O&M cavity provides O&M interface to users, including internal running status

indicator, MMI, system debugging port and transmission mode selection.

In addition, IOMU also includes an iSite Power Supply Unit (IPSU), whose power

comes from the 27V of the power supply module. After DC/DC conversion, it can be

converted to multiple power supply such as !8V, +5V and +3.3V to supply power to

boards of the system. Moreover, IPSU respectively provides one channel of backup

+5V and +3.3V power supply, so power supply to IMOU and IASU can be sustained

temporarily to support alarm report when AC power supply is cut off.

II. Access SDH Unit

IASU supports 2M interface to accomplish mini BTS embedded SDH transmission. It

can be flexibly configured as terminal multiplexer or add/drop multiplexer. With this unit,

combined networking can be implemented, including ring networking, link networking,

point-to-point network topology and other more complex networking such as star

networking, tangency ring networking, intersecting ring networking, ring-link combined

networking etc. It has powerful channel protection and multiplexing segment protection

function.

III. LightningProof Unit

ILPU accomplishes the conversion of external signals (E1 signal and alarm signals)

from external interfaces to IOMU, and the lightningproof and current limitation of the 2

channels of E1 signals and 5 channels of alarm signals of IOMU. The E1 signal

lightningproof module on the IOMU is serial connected to E1 signal cable and the alarm

signal lightningproof module is parallel connected to alarm signal cable so that lightning


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current will not enter the board via E1 or alarm cable and strong lightning current can be

led to GND cables when the BTS is struck with lightning.

IV. BTS3002C Motherboard Unit

IBMU transmits power and data signals with strong anti-interference capability and

reduces the quantity of the cables required.

3.3.2 Transceiver Subsystem

Transceiver subsystem is composed of ITRU and IPAU and provides signal baseband

processing and RF processing functions as detailed in the following.

Channel encoding and decoding, interleaving and de-interleaving, digital

modulation and demodulation, speech encryption and decryption and rateadaptation.

Frequency hopping, power control and temperature detection.

Accomplish mapping between logic and physical channels.

Accomplish intra-cell and inter-cell handover.

Signal up/down frequency conversion, filtering and amplifying.

Provide transmission RF signal between transceiver subsystem and antenna and

feeder subsystem.

Circuit self-check.

Alarm collection.

I. Transceiver Subsystem Works Process

Transceiver subsystem works according to the following process:

Uplink: Transceiver subsystem receives radio signals from antenna and feeder

subsystem, which are converted into analog intermediate frequency signals after

balanced amplifying and mixed frequency filtering. Then, after A/D sampling, these

signals are conversed into digital intermediate frequency signals, which further become

baseband signals after digital down-convert, receiving filtering and digit automatic gain

control. After balancing, these signals are sent to BSC via transmission subsystemafter demodulation, decryption, de-interleaving, channel coding and rate adaptation.

Downlink: Transceiver subsystem receives data from BSC via main control subsystem.

Then after A/D conversion, speech encoding, channel encoding, interleaving, TDMA

burst pulse is generated. Then, after encryption, GMSK modulation, D/A conversion,

low-pass filtering, I/Q analog signals are generated. Then, I/Q analog signals are

transmitted to transmitting carrier after orthogonal modulation. Then, they are sent to power

amplifier to be amplified into a certain level after amplifying and filtering. Finally, they are

transmitted via antenna and feeder subsystem.


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II. Transceiver Unit

ITRU is composed of Tx unit, Rx unit and iSite BaseBand Unit (IBBU). Tx unit

accomplishes the modulation from baseband signals to RF signals, and also executes

RF frequency hopping and signal driving. Rx is responsible for RF signal demodulation,

frequency hopping and diversity receiving and bypass. IBBU implements all baseband

processing functions of all duplex channels in one TDMA frame, including signaling

processing, channel coding/decoding, interleaving/de-interleaving and demodulation.

IBBU also supports speech services, data services and GPRS services specified by

Phase 2.

III. Power Amplify UnitIPAU accomplishes the amplifying of RF output signals and supports the static and

dynamic power control of BTS3002C.

IV. Antenna and Feeder Subsystem

Antenna and feeder subsystem is composed of IDFU, attached combiner, antenna and

feeder.

V. Duplexer Filter UnitIDFU includes 1 duplexer and 1 diversity receiving filter and they are integrated into

one module. The Rx/Tx port of the module is designed with waterproof technique, so itfeatures low insertion loss and high suppression. IDFU is used to isolate the

transmitting and receiving of RF signals, and suppress transmitting/receiving outband

spuriousness and external interference signals. With IDFU, the number of antenna

used can be reduced.

Figure 3-4, Figure 3-5, Figure 3-6 and Figure 3-7, illustrate how IDFU implements

various antenna and feeder configurations. In these figures, DUP means duplexer, FIL

means diversity receiving filter, LNA means Low Noise Amplifier, RXm means main

receiver, and RXd means diversity receiver. Whether omni antenna or directional

antenna will be configured depends on actual implementation.

Figure 3-4shows the configuration of single carrier (dual feeder). As shown in the

figure, there are 3 antenna feeder port in IDFU, Tx/Rx duplex port (Tx/Rx_ANT),

diversity Rx port (Rx_ANT) and jumper port when one carrier of the dual carrier is

mutually the other's diversity (Rx_OUT).

This type of configuration is applicable to O1 and S1 sites. For O1 site, the antenna can

be two omni-directional ones; for S1 site, the antenna can be two unipolar ones or a

bipolar one. If the two carriers of BTS3002C adopt this configuration, this site can

become a S (1/1) site.


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IPAU DUP

FIL

RXm

RXd

IDFU

ITRU

TX/RXA

RXB

X

XLNA

X in the figure means antenna and feeder output port, so does it in the next 3 figures.

Figure 3-4 Configuration of single carrier (dual feeder)

Figure 3-5shows the configuration of single carrier (single feeder). Single antenna can

be adopted to reduce the number of antenna. Under this configuration, internaldiversity can be achieved if jumper port and diversity Rx port are connected, which has

been proved by experiment that the sensitivity of antenna are improved by 1dB.

This type of configuration is also applicable to O1 and S1 sites. Its difference from the

single carrier (dual feeder) is that the only one omni-directional antenna or a directional

unipolar antenna is enough for setting up the O1 or S1 site. S (1/1) site can also be

configured by adopting this configuration for the two carriers.

IPAU DUP

FIL

RXm

RXd

IDFU

ITRU

TX/RX

X

Figure 3-5 Configuration of single carrier (single feeder)

Figure 3-6 shows the configuration of dual carrier (dual feeder). This type of

configuration is applicable to O2 and S2 sites. For O2 site, the antenna can be two

directional ones; for S2 site, the antenna can be two directional unipolar ones.


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IPAU DUP

FIL

RXmA

RXdA

IDFU

ITRU

TXA/RXA

IPAU DUP

FIL

RXmB

RXdB

IDFU

ITRU

TXB/RXB

X

X

Figure 3-6 Configuration of dual carrier (dual feeder)

Attached combiner combines (806MHz ~ 866MHz) is optional, and it can saves number

of antenna and feeders.

Figure 3-7 shows the configuration of dual carrier (single feeder) with attachedcombiner. This type of configuration is also applicable to O2 and S2 site. Its difference

from the dual carriers (dual feeder) configuration is that only one omni-directional or

directional unipolar antenna is enough to set up the O2 or S2 site since the external

combiner is adopted.


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IPAU DUP

FIL

RXmA

RXdA

IDFU

ITRU

TXA/RXA

IPAU DUP

FIL

RXmB

RXdB

IDFU

ITRU

TXB/RXB

TX/RX

Combiner X

Figure 3-7 The configuration of dual carrier (single feeder)

Antenna is the end point of signal transmitting and the beginning point of receiving,

including omni antenna and directional antenna. The type, gain, coverage direction and

front-to-rear ratio of the antenna determine system performance, so network designers

select the type of the antenna required according to such parameters as traffic and

coverage etc.

Feeder transmits the uplink and downlink signals between the transceiver and antenna

via low-loss RF cables.

3.3.3 Heating Subsystem

Heating subsystem includes temperature control circuit and film heating board. Film

heating board can raise the temperature of the environment when the internal

temperature of the BTS becomes too low so that the mini BTS can still work under the

temperature of -40C. MCU and DRU get heated independently.

3.3.4 Power Supply Subsystem

Power supply subsystem is composed of power module and supplies power to boards

of other subsystem. There are two types of power module: AC/DC PSU and DC/DC

PSU.

After converting the input 220V AC into +27V DC, AC/DC PSU supplies power to power

amplifier module and film heating board, supplies input power to IPSU part on IMOU, as


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well as provides one channel of +27V backup power (used when AC is cut off) and one

channel of +5V temperature-controlled circuit power.

After converting the input 220V AC into +27V DC, DC/DC PSU supplies power to power

amplifier module, and supplies input power to IPSU part on IMOU.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 4 Functions


4-1

Chapter 4 Functions

4.1 Basic Functions

Integrated mini BTS has the following basic functions:

Support GSM services

Phase II+ all data services prescribed

GPRS basic services

Phase I/Phase II /Phase II+ compatible LAPDm protocol

CS-1/CS-2/CS-3/CS-4 radio channel-coding methods. Phase I/Phase II/ Phase II+ compatible system message broadcasting and

resource indication

Support Abis bypass

Enhanced full rate (EFR) speech coding scheme with better speech quality

Data service: including transparent transmission of 9.6k, 4.8k, 2.4k,

non-transparent transmission of 12kbit/s (9.6k), 6kbit/s (4.8kbit/s), faxing and

WWW browsing), point-to-point short message and cell short message

broadcasting.

16KBIT/S and 64KBIT/S signaling traffic.

Paging queue

A5/1 and A5/2 encryption/decryption

Basic data dynamic configuration

Dynamic resource management

Measurement report preprocessing

Immediate assignment combination and paging combination, boosting the radio

channel usage

Discontinuous transmission(DTX) and Discontinuous Reception(DRX) enhancing

the anti-interference ability

Omnidirectional cell and directional cell. It supports O1, O2, S1, S2, S1/1, S1/1/1,S2/2 and S2/2/2 site configuration mode.

Support locked, fast capture, track (normal), hold-over and free-run clock modes

Synchronous handover, asynchronous handover

Um interface tracing and inner interface tracing

Local and remote software downloading

Satellite transmission function

Static and dynamic power control

Directly optical transmission

Support star, tree, chain and ring networking


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4-2

4.2 Digital Trunking Function

Huawei GSM-T BTS3002C supports the following digital trunking functions:

4.2.1 VGCS

Service subscribers can become group members on a PLMN wide basis to one or more

groups pre-defined in the network by a corresponding group identification (group ID).

The membership enables them to initiate or receive voice group calls associated with

that group ID. Certain dispatchers connected to external networks also require the

capability to initiate or receive voice group calls.

4.2.2 VBS

Service subscribers can become group members on a PLMN wide basis to one or more

groups pre-defined in the network by a corresponding group identification (group ID).

The membership enables them to receive voice broadcast calls associated with that

group ID. In addition, certain group members are entitled by their subscription to initiate

voice broadcast calls. Certain dispatchers connected to external networks also require

the capability to initiate or receive voice broadcast calls.

4.2.3 Fast Group Call Setup

The function is based on the eMLPP function. If a group subscribes the service, the

system adopts fast group call setup process to set up a group call.

4.2.4 Late Entry

The process of broadcasting messages on NCHs is to be carried out throughout the

call in order to provide the facility whereby group members entering the area can join

the call.

4.2.5 eMLPP

The enhanced Multi-Level Precedence and Pre-emption service (eMLPP) provides

different levels of precedence for call set-up and for call continuity in case of handover.


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inter-group subscriber will not occupy A interface circuit. So the A interface circuits will

be saved.

4.2.13 800M Band Supported and 800M Hopping

The BSS supports the T-GSM 800M frequency band: 806MHz-821MHz(MS

transmitting, BTS receiving); 851MHz-866MHz(BTS transmitting, MS receiving) the

duplex distance is 45MHz.

Hopping can decrease the interference effectively. GT800 support the hopping of the

group call channel and improve the performance of the anti-interference.

4.2.14 Reserved Channel

The TCH channels can be reserved for a specific Enterprise, only the subscribers in the

specific Enterprise can use these TCH channels, other subscribers cannot use these

TCH channels, so that the service originated by the specific Enterprise subscriber can

get the TCH immediately.

4.2.15 Trunking Emergency Call

The enterprise manager assigns an address for each member of the enterprise, this

address can be group ID or one or two common telephone number. When the

subscriber originates the trunking emergency call by pushing the emergency call button,

the network will connect this emergency call to this emergency address.

1) If this emergency address is a group ID, the network will originate a group call as

the subscriber is a dispatcher.

2) If this emergency address is one common telephone number, the network will

originate a common point to point call.

3) If this emergency address is two common telephone number, there is two way for

the network to connect them, one way is connecting them one by one, the other

way is connecting them at the same time,

If the subscriber selects the one by one way, the network will connect to the first

number if the network gets answer from the first telephone number. or else the

network will try to connect the second telephone number.

If the subscriber selects the at the same time way, the network will try to connect

these two common telephone numbers at the same time, and it will connect to the

telephone number which answer first, and the other telephone number will be

released.


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4-5

4.2.16 Fall Back

When the transmission is interrupted between BTS and BSC, the BTS will work in fall

back mode. BTS with fall back mode will support base function like VGCS, VBS, uplinktime limit. The fall back mode support one cell or multi-cell in the BTS. When the

transmission is ok, the fall back BTS will work like normal.

4.2.17 Stand Alone

The BTS can work without BSC and NSS. The BTS in stand alone mode can support

VGCS, VBS.

4.3 Networking Functions

4.3.1 E1 Networking

BTS3002C supports star, chain, ring and tree networking that are shown respectively in

Figure 4-1, Figure 4-2, Figure 4-3and Figure 4-4. In these figures, each line stands for

E1 cables. The maximum limitation of the cascading level is 5 for the chain networking

mode.

I. Star Networking

BSC

BTS3002C

BTS3002C

BTS3002C

Figure 4-1 BTS3002C star networking mode

II. Chain Networking

BSC BTS3002C BTS3002C BTS3002C

Figure 4-2 BTS3002C chain networking mode


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4-6

III. Ring Networking

BSC BTSBTS BTS

Figure 4-3 BTS3002C E1 ring networking

IV. Tree Networking

BSC

BTS

BTS

BTS

BTS

Figure 4-4 BTS3002C E1 tree networking

4.3.2 SDH Networking

SDH networking supports both chain and ring modes. Two modes of SDH networking

are shown in Figure 4-5and Figure 4-6. In these figures, each single line stands for E1

cables and a pair of lines stands for optical fibers. The maximum limitation of the

cascading level is 5 for the chain networking mode.

BTS3002C BTS3002CBSCOptical

transceiver

Figure 4-5 BTS3002C chain networking

BTS3002C BTS3002CBSCOpticaltransceiver BTS3002C

Figure 4-6 BTS3002C ring networking


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4-7

4.3.3 Combined Networking

Combined networking can be adopted for BTS3002C. Under combined networking

mode, SDH link networking is adopted for Abis interface and E1 cascaded networkingis adopted for circuit side, as shown in Figure 4-7, in which, each single line means E1

cables and each double lines means optical fibers.

BSCOpticaltransceiver BTS3002C BTS3002C BTS3002C

BTS3002C BTS3002C

Figure 4-7 BTS3002C combined networking

4.4 Radio Network Functions

4.4.1 Diversity Receiving

A radio channel is a random time-variable channel with fading features, while the

diversity receiving technology is an effective anti-fading technology. Radio signals that

are transmitted to RX through radio channels are combination of various multi-path

components. These signals carry the same message and are featured with irrelevant

random fading characteristics. By the diversity receiving technology, these signals can

be combined into general receiving signals so as to diminish the effect caused by

fading.

The diversity receiving methods include frequency diversity, time diversity, polarity

diversity and space diversity. In BTS3002C, polarity diversity, space diversity and

frequency diversity are used to diminish the signal fading.

4.4.2 RF Hopping

Frequency hopping is an important method to improve the performance of a BTS. It

cannot only improve the anti-fading ability of up- and down-link channels, but also

improve the security in communications. BTS3002C, introducing dynamic loop

bandwidth technology and PingPong handover technology, performs real-time

switchover between two clock synthesizers to implement RF hopping. This method of

RF hopping implementation is highly reliable and lowers the requirement for the speed

of clock synthesizers.


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4.4.3 Power Control

The BTS power control can be adjusted by BSC to ensure MS stable receiving signal

strength. As a result, interference between neighboring channels and BTS powerconsumption can be decreased. BTS3002C supports both static and dynamic power

control.

The BTS3002C static power class is divided into 11 levels (0 ~ 10 level, 2dB/level), and

the maximum output power of BTS is 0 level. For example, if the maximum transmit

power of the BTS3002C is 20W, then 0 level corresponds to 43dBm and the 10 level

corresponds to 23dBm.

BTS dynamic power control is a fine tuning operation based on the static power control

and the class of it is divided into 15 levels (0 ~ 15) level, level 0 is the same as that of

static power control). Ifthe current maximum transmit power is set to be Pm, then the

dynamic power control range will be Pm ~ (Pm-30) dBm. When the maximum value of

dynamic power control cannot meet relevant requirement, static power control level

should be adjusted to correspondingly increase the maximum magnitude of output

power of the dynamic power control.

4.4.4 Uplink Frequency Scanning

Uplink frequency scanning is a special network function of BTS3002C. To know the

frequency interference of coverage area for network optimization, downlink frequencycan be easily get from the test MS, while it is more complicated to get the uplink

frequency. Therefore, BTS3002C provides uplink frequency scanning function to scan

uplink frequency for uplink data quality control according to network optimization

parameter configuration by utilizing idle TSs of the frequency.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 5 O&M System


5-1

Chapter 5 O&M System

5.1 O&M Functions

BTS3002C O&M system provides the user with powerful O&M functions in

consideration of the users requirements in equipment performance and maintenance.

These functions include: security management, alarm management, maintenance

management, performance measurement and test, etc.

5.1.1 Security Management

In view of various remote maintenance operations implemented by the O&M system,

the system provides powerful security management system to execute O&M control

over the equipment in order to avoid unauthorized operations which may affect normal

performance of the equipment.

The user must log in and go through authentication before performing O&M to

BTS3002C. The system provides an authorization system with multiple levels to ensure

that only authorized users can execute relevant commands for O&M. Meanwhile,

dialog boxes are prompted before any important O&M command is executed to getconfirmation for the potential problems due to the operations

5.1.2 Alarm Management

BTS3002C O&M system provides highlighted alarm windows and powerful real-time

alarm management functions, such as collection, clearing, query, processing, saving,

explanation, prompting, shielding, filtering, acknowledging, analyzing, etc. Besides, it

also provides on-line help information system and stage filtering system to help the

user with quick fault location. It also provides alarm recovery methods.

5.1.3 Maintenance Management

The operation & maintenance center (OMC) implements management over the whole

BSS through BSC. Each entity in BTS can perform check and location functions for

internal errors so that BSC can implement maintenance to BTS without knowing the

internal structure of each entity.

The O&M system can monitor and query the states of boards and the system, keeping

the user aware of the system running states. It supports automatic backup of data with


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5-2

backup time intervals and directory being customized. It also supports reset of key

parts and in-service loading and activation of equipment software.

5.1.4 Performance Measurement and Test

The O&M system can implement performance measurement and test to the equities so

as to collect BTS running states data and perform accurate analysis on the running

states.

It supports real-time monitoring to partial resources of BTS3002C that can be displayed

in graphics, facilitating fault location or performance measurement analysis for the user.

These resources include CPU occupancy, RAM occupancy, etc.

Test functions that BTS3002C provides include:

I. Carrier Channel Test

Idle burst test

TRX loop test

II. Functional Objects Self-test Site self-test

Cell self-test

Carrier self-test

Board self-test

5.2 O&M Structure

5.2.1 Overview

BTS3002C is managed by BSC and it is connected after being routed to the upper level

network management system (NM system) through Q3/core database interface, or to

iManager integrated NM system. Both NM systems implement overall O&M to the

equipment to help the user with O&M management.

BTS3002C provides two maintenance modes: local maintenance and remote

maintenance (as shown in Figure 5-1). The maintenance system uses an O&M

interface with unique navigation tree technology, taking full advantage of the visualized

and easy-to-memorize graphical user interface (GUI). The user interfaces of both

modes are similar, providing highly visualized equipment panel view.


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5-3

Local Maintenance

Console

Remote Maintenance

Console

MMI

MMI

BTS

BTS

BSC

Abis

Abis

OMC

Server

Hub

Remote Maintenance

Console

Figure 5-1 Remote and local maintenance

5.2.2 Local Maintenance

Local maintenance refers to the maintenance mode in which PCs are connected to

BTS3002C by serial port lines and implement maintenance operations to the BTS.

The local maintenance console can only be accessed after the local maintenance

software is installed in PCs. The BTS local maintenance is carried out based on

different objects of the BTS, which include site, cell, carrier, baseband and board.

Real-time alarm messages can also be obtained at the same time. Functions of local

maintenance include:

Board software loading and activation. BTS3002C will perform centralizedmanagement over the software versions. While the user will choose the software

version to be run.

Set attributes for BTS, carrier and channels, and partial extension attributes for the

air interface.

Board and BTS reset.

Query for versions of software and hardware (some boards).

Communicate with UPS via specific interface and manage backup power supply.

Usage states of some BTS3002C resources being real-time monitored are

displayed in graphics to facilitate fault location and performance diagnosis. The

states include CPU occupancy, RAM occupancy, etc.

The board maintenance interface displays a real physical map of the mini BTS

equipment facilitating the users check on the running state of the BTS. Real-time

display of board states and relevant query control concerning the circuit board is

also provided.

Function self-test and loop test for faults in communication loops.


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5-4

5.2.3 Remote Maintenance

Remote maintenance is performed through OMC. PCs are connected to BSC via OMC

network and are connected subsequently to BTS via the Abis interface.

The remote maintenance console can only be accessed via OMC Shell of the work

station (WS). The user interface of the BTS remote maintenance system is in

topological structure, where names, categories, locations, numbers, equipment types

and running states (normal, alarm, etc.) of all NEs in the mobile network can be

browsed. The user can specify a NE to be maintained and check detailed performance

data, alarm data and configuration data. He is also supposed to implement O&M to

certain type of NEs via the topological map.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 6 Reliability Design


6-1

Chapter 6 Reliability Design

6.1 System Reliability Design

6.1.1 System Fault Monitoring and Handling

The system is able to perform auto detect and software and hardware fault diagnosis,

and report alarms. It can record and print the fault information, and can collect UPS

state information.

The board protection mechanism is adopted in BTS3002C, which ensures timely reset

of the whole system for self-healing when a program is in abnormal operation.

There are temperature monitoring subsystem and heat subsystem in BTS3002C.

When the temperature is too low, the heating board will start automatically to heat the

whole BTS. While when the inside temperature is too high, relevant alarm will be

reported until the power supply module initiates shutdown of the BTS due to high

temperature.

6.1.2 Derate Design

For high-power parts and overheating parts, their rated power should be derated.

Therefore, the electric stress and thermal stress these parts bear in practice will be

lower than the rated values, and their parameter degeneration can be suspended and

life can be prolonged.

6.1.3 Temperature Design

The product is designed (through selection of parts, circuit and structure design and

heat-sink design) to work reliably in a wide range of temperature avoiding effect on

product performance due to temperature change.

6.1.4 Electromagnetic Compatibility Design

In this design, the equipment is supposed to avoid un-allowed degrading due to

electromagnetic emission of other equipment in the same environment. In the mean

time, it is not supposed to cause un-allowed degrading to other equipment, subsystems

or systems in the same environment due to its electromagnetic emission.


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6-2

6.1.5 Reliability Design for Input Voltage

BTS3002C uses broad voltage and has primary power supply inside. It allows an input

voltage range of 150 ~ 300V AC. Equipment will not get damaged during 350V ACinstantaneous input so that impact of power fluctuation upon the equipment can be

mitigated.

6.1.6 Reliability Design for Fault Detection

When DRU and heating board get faulty, faults can be detected and reported to the

background and fault detection rate reaches more than 90%. When MCU gets faulty,

major fault mode can be detected and corresponding alarms can be reported under the

condition that communication between BTS3002C and BSC or OMC is maintained.

6.2 Hardware Reliability Design

6.2.1 Inverse Connection Indication

When installing BTS3002C, if the receiving and transmitting ends of E1 or optical fiber

are inversely connected, the cable interface indicator will generate indication.

6.2.2 Avoiding Misplugging for Cable Connectors

Labels are stuck on the cable connectors with main labels stating manufacturers,

numbers, versions and other information to facilitate proper connections. Measures are

taken in the 220V three-phase power input connectors to avoid mispluging. Non-nude

connectors can be safely plugged into the power supply.

6.2.3 Signal Protection

To avoid effect to the chips caused by power fluctuation (at power-on or power-off

especially) all working power supplies in internal boards of BTS3002C will go throughstrict filtering process before being connected to the chips.

RS232 interface signal: use special protection device for RS232 interface

E1 transmission signal: protection on E1 transmission signal can be best

illustrated in lightning protection. BTS3002C employs asymmetry transient

depression diode to avoid damage to E1 cables caused by lightning.


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6-3

6.2.4 Reliability Design for RF Cables

The RF connector shell is reliably connected with the metal layer of structural part for

EMC after it is connected with shielding layer of cables. SMA connector is used toensure the reliable connection between sockets and plugs.

6.3 Software Reliability Design

6.3.1 Fault Isolation Feature

The software design is featured by the module fault isolation, which means faults that

occur in a software module are restricted in this module and should not originate faults

in other modules. The software has the ability of fault tolerance and correction. Minorfaults in software running will not initiate reset or restart of the system.

6.3.2 Operational Security

BTS3002C is easy to be connected. Its definite indications for performance and fault

can help with quick clearing of faults. The software for MMI and OMC is compatible with

indoor BTS with easy-to-use interface.


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System DescriptioniSite BTS3002C Integrated Mini BTS Chapter 7 Technical Indices


7-1

Chapter 7 Technical Indices

7.1 Overall Engineering Indices

Table 7-1 BTS3002C overall engineering indices

Parameter name Indices

Cabinet size

(height%width%depth)

700mm%460mm%360mm

Weight 55kg

Single carrierconfiguration,uninterrupted working(power supply for thewhole cabinet)

No heating: 140W (-10C ~

+55C)

With heating: 400W (-20C ~

-10C)

Dual-carriersconfiguration,uninterrupted working(power supply for thewhole cabinet)


+55C)


-20C)

Power consumption

Single carrierconfiguration, lowtemperature startup(power supply for thewhole cabinet)

Startup when environment

temperature is at -40C ~

-5C, the consumption is440W. When the cabinetinternal temperature reaches


30C, the consumption is140W.


temperature is at -5

C ~ 0

C,the consumption is 400W.When the cabinet internal

temperature reaches 30C,the consumption is 140W.


temperature is above 0C, theconsumption is 140W.


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7-2


Dual-carriersconfiguration, lowtemperature startup(power supply for thewhole cabinet)


temperature is at -40C ~



30C, the consumption is260W.


temperature is at -5C ~ 0C,the consumption is 640W.When the cabinet internal

temperature reaches 30C,

the consumption is 260W.


temperature is above 0C, theconsumption is 260W.

Single carrierconfiguration (powersupply by priority)


+55C)


-10C)

Dual-carriersconfiguration (power

supply by priority)


+55C)


-10C)

Working environmenttemperature

Normal operation in -40 ~ 55C

Working environmentrelative humidity

5% ~ 100%

Clock

Frequency: 1.3%107Hz, ex-factory precision higher than

0.05ppm

Frequency feature:

(from0C to70C)

Annual aging rate:

Input power supplyWhen 220V AC input : 150 ~ 300V AC , 47 ~ 63Hz

When -48V DC input : -40V DC ~ -60V DC

Security performance Comply with IEC60950 standards

Anti-vibrationperformance

Comply with IEC Class 4M3 standards

Electromagneticcompatibility

Comply with ETS 300-342-3 standards


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7-3


Waterproof anddustproofperformance

Comply with IP55 standards

7.2 Overall Performance Indices

Table 7-2 BTS3002C overall performance indices

Performancecategory


Channel capacity 16CH/carrier

Frequency band 200kHz

R-GSM 900:

Uplink: 876 MHz to 915 MHz

Downlink: 921 MHz to 960 MHz

DCS 1800:

Uplink: 1,710 MHz to 1,785 MHz

Downlink: 1,805 MHz to1,880 MHz

System indices

Bandwidth

T-GSM 800:

Uplink: 806 MHz to 821 MHz

Downlink: 851 MHz to 866 MHz

Static receivingsensitivity

R-GSM 900:-110dBm

DCS 1800:-109dBm

Congestionfeatures

Comply with GSM11.21 specifications

Anti-interference

features Comply with GSM11.21 specifications

Intermodulationrejection


Receivingperformance

Stray radiation Comply with GSM11.21 specifications

Max. transmitpower per carrier

Antenna feeder port43dBmTransmittingperformance

Static power controlrange

0 ~ 10 level


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7-4

Performancecategory


Dynamic powercontrol range

0 ~ 15 level

Transmit powerabsolute precision

2 !0.5dB (normal temperature)

2 !1dB (all temperature)

Transmit spectrum Comply with GSM11.21 specifications

Intermodulationrejection


Stray Radiation Comply with GSM11.21 specifications

Frequency error 0.05ppm

Phase error 5(rms)

20(peak)

7.3 External Physical Interfaces

Table 7-3 BTS3002C external physical interfaces

Interface name Type Quantity Functions

E1 2 pairs

Provide E1 interface of75/120

Support cascade

Provide operation andmaintenance link(OML)

Abis interface

STM-1 2 pairs

Provide SDH transmissionmode

Support cascade

Provide operation andmaintenance link(OML)


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Interface name Type Quantity Functions

Alarm interface ALARM 6

Dry connector alarminterface: supports reportingfour channels of dry

connector alarm signal

TTL level alarm: supportsone channel of TTL levelsignal alarm, for connectingexternal UPS alarm signal

485 port alarm: supports onechannel of duplexcommunication, forconnecting external alarmequipment such as alarmbox

FCLK 1 FCLK test portClock interface13MCLK 1 13MHz clock test port

MMI (J2) 1 Provide local maintenance

Network port(J1)

1 IOMU network portMaintenanceinterface

Network port(J6)

1IASU network port, providingmaintenance channels.

PowerSupply

1220V AC power input port

or -48V DC power input portPower supply andgrounding

Grounding 1220V AC grounding terminal

or -48V DC grounding terminal

Tx/Rx_ANT 1 Tx/Rx duplex port

Rx_ANT 1 Diversity Rx portAntenna and feedercable interface

Rx_OUT 1Jumper port when one of thedual carrier is mutually theother's diversity.

Note:

FCLK and 2M are multiplexed. When line clock is required to be tested on the BTS side,

FCLK can be set as default and they (either FCLK or 2M) can be switched through

operations on remote or local maintenance console.

01 system description of bts3002c

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