01 System Description

Technical Manual − System Description M900/M1800 BTS3X Series Base Transceiver Transceiver Station

Chapter 1 Introduction

Chapter 1 Introduction 1.1 Current Status and Demands Demands of GSM Network Network Since Since the middle middle 1980 1980s, s, publi public c mobil mobile e commu communic nicati ation ons s have have witne witnesse ssed d two genera generations tions of developm development ent with the further further develop developmen mentt of cellular cellular networki networking ng technologies and the emergence of high-capacity mobile telecommunications system. 

The first generation is an analog mobile telecommunications system, which only provides speech services using FDMA technologies.



The second generation is a digital mobile telecommunications system, which appeare appeared d in 1990s 1990s with relevant relevant standar standards ds including including GSM, IS-95, IS-95, etc. This system system is mainl mainly y used used for speec speech h servic services es and and provi provides des low low speed speed circui circuitt switched data services at the same time.

At present, GSM communications communications network is being applied around the world. More and more people have recognized its big potential of development. The market demands for the GSM network cover the following aspects: 

The base transceiver station (BTS) of larger capacity is required because of the dramatic increase in the number of mobile subscribers and the heavier traffic.



Higher multiplexing ratio over the Abis interface is required due to expensive transmission resources.



It is required to reduce the equipment room size for cost saving.



Complicated transmission mode requires powerful BTS transmission transmission adaptability adaptability and multiple built-in transmission equipment.



The continuous continuous expansion expansion of GSM system require requires s that BTS be expande expanded d flexibly and the existing investment be protected against waste during system expansion.



Service demands of mobile subscribers keep increasing, which requires requires the BTS to support more services.



Since the power supply system is unstable, power supply of BTS is required to adapt to a wider range of voltage fluctuation and to have certain protection mechanism which ensures fast BTS recovery after it is powered on again.



BTS is required to provide better voice quality and faster switchover.

A series of macro cell BTSs are developed developed by Huawei to meet the above demands. demands. The series of BTSs provide provide a network network solution solution to conveni convenience ence in maintena maintenance, nce, operation operation and management in densely populated areas and cities with large capacity requirement.

Huawei Technologies Proprietary 1



1.2 Product Orientation BTS3X is the series of proprietary macro cell BTS developed by Huawei. The BTS series include: 

Indoor BTS30



Indoor BTS312



Outdoor BTS3006A



Outdoor BTS3012A

The above types of BTS can meet the requirements in multiple conditions. Table 1.1 gives a brief introduction to the BTS3X series. Table 1.1 BTS3X macro cell series BTS3X product

Maximum number

model

of TRXs of a single

Application

cabinet BTS30 (indoor BTS)

6 TRXs

Densely populated areas and cities

BTS312 (indoor BTS)

12 TRXs

Areas with high density and large traffic

BTS3006A (outdoor

6 TRXs

Suburb or small town with

BTS)

medium traffic

BTS3012A (outdoor

12 TRXs

Area in the urban where it is

BTS)

difficult to select an equipment room

BTS30 is a highly integrated indoor macro cell BTS with low power consumption, featuring small size, high reliability and flexible networking. It can be applied to most of the densely populated areas and cities. BTS312 is highly integrated indoor macro macro cell BTS with large capacity and low power consumption, which saves more room to facilitate expansion. It is mainly applied to support cells with high density and large traffic. BTS3006A and BTS3012A are outdoor macro cell BTSs with 6 TRXs and 12 TRXs respectively that can adapt to complex climates and electromagnetic environment. They feature low cost, fast site construction, construction, high environment environment adaptability, adaptability, serving as a majo majorr supple suppleme ment nt to indoo indoorr BTS. BTS. They They provi provide de a comple complete te soluti solution on to the construction of seamless mobile communication networks.




1.2 Product Orientation BTS3X is the series of proprietary macro cell BTS developed by Huawei. The BTS series include: 

Indoor BTS30



Indoor BTS312



Outdoor BTS3006A



Outdoor BTS3012A

The above types of BTS can meet the requirements in multiple conditions. Table 1.1 gives a brief introduction to the BTS3X series. Table 1.1 BTS3X macro cell series BTS3X product

Maximum number

model

of TRXs of a single

Application

cabinet BTS30 (indoor BTS)

6 TRXs

Densely populated areas and cities

BTS312 (indoor BTS)

12 TRXs

Areas with high density and large traffic

BTS3006A (outdoor

6 TRXs

Suburb or small town with

BTS)

medium traffic

BTS3012A (outdoor

12 TRXs

Area in the urban where it is

BTS)

difficult to select an equipment room

BTS30 is a highly integrated indoor macro cell BTS with low power consumption, featuring small size, high reliability and flexible networking. It can be applied to most of the densely populated areas and cities. BTS312 is highly integrated indoor macro macro cell BTS with large capacity and low power consumption, which saves more room to facilitate expansion. It is mainly applied to support cells with high density and large traffic. BTS3006A and BTS3012A are outdoor macro cell BTSs with 6 TRXs and 12 TRXs respectively that can adapt to complex climates and electromagnetic environment. They feature low cost, fast site construction, construction, high environment environment adaptability, adaptability, serving as a majo majorr supple suppleme ment nt to indoo indoorr BTS. BTS. They They provi provide de a comple complete te soluti solution on to the construction of seamless mobile communication networks.



Chapter 2 Product Features

Chapter 2 Product Features 2.1 BTS3X Technological Technological Characteristics The The BTS3 BTS3X X seri series es are are desi design gned ed as a typi typica call allall-in in-o -one ne BTS BTS by taki taking ng full full consideration of the requirements in capacity, configuration, installation, power supply, transmission, and services. This section introduces its characteristics below.

2.1.1 Integrated Integrat ed RF Component Technology Technology 

Expansion based on the inheritance of the investment: BTS expansion can make the utmost us of all the antenna and feeder parts.



Modular structure with good performance: RF combiner, divider and low noise amplifier are integrated in the combining and distribution unit (CDU). All parts for TRX processi processing, ng, which which include include baseban baseband d processi processing, ng, RF processi processing, ng, power power amplification and power supply, are integrated in one transceiver unit (TRX). The modul modular ar struct structur ure e can reduce reduce inter interna nall cable cable conne connecti ction ons, s, improv improve e system system reliability and facilitate installation and maintenance.



Intelligent CDU: The CDU features fine monitor and control functions, excellent O&M, level 2 standing wave ratio alarm, low noise amplifier alarm, tower top amplifier (TTA) alarm, TTA power supply. It also supports auto protection against emergency, that is, it can close transmit power when the Tx channel of the antenna and feeder is abnormal, and can power off to bypass the low noise amplifier (LNA) when TTA is abnormal so as to ensure normal system operation. operation. Receive gain can be adjusted via remote control to ensure the sensitivity of the receive system.

2.1.2 Mature RF Technology 

RF hopping and baseband frequency hopping are provided to improve system anti-interference capability. It has good performance in practical applications.



The advanced advanced digital digital RF technol technology ogy is adopted adopted to raise raise batch batch consisten consistency, cy, manufacture manufacture scalability and stability of the RF system.

2.1.3 Advanced E-Abis Technology The enhance enhanced d Abis (E-Abis) (E-Abis) support supports s various various transmi transmission ssion modes modes and complex complex topologies. The transmission mode can be SDH, E1, microwave, or satellite.




The E-Abis includes the following techniques: 

Advanced clock phase phase locking (APL): solves the problem of clock jittery by using highhigh-pre precis cisio ion n (up (up to 0.1 Hz) clock clock and charac character terist istic ic softwa software re phase phase lock lock technique. Problems such as SDH clock phase jittery and signal out of lock during transmission via satellite are solved.



The system can tolerate a tolerance at the bit error rate of 1E-4, that is, 2 levels higher than the common 1E-6 bit error rate. A better and smooth voice quality can be obtained even in transmission through microwave and satellite.



The system can tolerate an intermittent link failure of less than 2 seconds, which makes the BTS3X more suitable for applications in unstable conditions such as SDH transmission switching, microwave, satellite transmission, transmission, etc.



Protecti Protection on against against long long transmiss transmission ion delay delay on the Abis to support support satellites satellites networking.

2.1.4 Powerful O&M Functions BTS3X can perform the following O&M functions: software downloading, BTS object attribut attribute e configu configuratio ration n managem management, ent, equipme equipment nt managem management ent and running running status status monitoring. 

Local Local mainten maintenance ance:: provide provides s man machine machine interfac interface e (MMI), (MMI), and impleme implement nt maintenance, monitoring and management to all objects of the BTS through the local maintenance system.



Remote maintenance: O&M network is made 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 provides system running indices indication, resource state indication.



Security Security manage management ment provide provides s MS login login authent authenticati ication, on, command command authori authority ty restriction, unsecured operation indication and user group management.



Test: auto-test of functions, loop-back test.



Upgrade: automatically checks the system for upgrade. System upgrading can be performed via remote loading. The system can be restored to its previous version if system upgrading upgrading fails.

2.2 Advantages of of BTS3X Applications 2.2.1 Large Capacity Capacity and Wide Coverage Coverage 

Large capacity of a single cabinet: BTS30 and BTS3006A can support up to 6 TRXs in the full configuration mode, while both BTS312 and BTS3012A can support up to 12 TRXs in the full configuration mode. Huawei Technologies Proprietary 2

Technical Manual − System Description M900/M1800 BTS3X Series Base Transceiver Station 


When a TRX is configured, the nominal value of transmit power at the antenna connector is 40 W. When the power boost unit (PBU) is equipped, the nominal value of transmit power can reach 80 W; When the enhanced duplexer unit (EDU) is adopted, the RF signal combining consumption can be reduced and the BTS coverage can be expanded.



The dual timeslot expansion function is supported. Theoretically, a maximum coverage of 120 km can be supported.

2.2.2 Cost Reduction 

It supports multiplexing of 15:1, hence greatly reducing transmission cost.



Transmission equipment such as SDH can be integrated with the cabinet, providing a solution for future upgrade and wideband radio access and reducing transmission equipment investment.



Centralized power supply provides power to various modules in a distributed way. BTS30 and BTS312 can provide DC +24 V, DC -48 V and AC 220 V to satisfy different power supply requirements.



BTS3006A and BTS3012A enjoy good performance in outdoor adaptability and reduced investment in accessories.

1)

Multiple cabinet types for BTS3006A and BTS3012A are provided to cater to the environment features of different areas. BTS3006A includes two types: the cabinet with an air conditioner (220V AC) and the cabinet with a heat-exchanger (110V AC with double live line). The BTS3012A includes four types: the cabinet with an air conditioner (220V AC), the cabinet with an air conditioner (110V AC with double live line), and the cabinet with a heat-exchanger (220V AC) and the cabinet with a heat-exchanger (110V AC with double live line).

2)

The BTS3006A and BTS3012A enjoy a wide working temperature range. The working temperature range of the cabinet with an air conditioner is -40 oC to +55oC (environment temperature), and that of the cabinet with a heat exchanger is -40oC to +50oC (environment temperature).

3)

The cabinet supports three-phase and single-phase power supply with wide voltage range for the 220 V power supply system: 150V AC to 276 V AC, and the tolerant voltage is 300V AC.

4)

The cabinet can adopt the double live line input method for the 110V power supply system (that is, adopt the two live lines with 120 degrees or 180 degrees phase difference, as shown in Figure 4.1).



Technical Manual − System Description M900/M1800 BTS3X Series Base Transceiver Station

Figure 4.1 110V power supply 5)

Designs for waterproof, dustproof, moisture proof, acid proof, mildew proof, and ultraviolet radiation protection meet the IP55 protection standards.

6)

Two types of storage battery box can be selected: built-in storage battery box and extended storage battery cabinet. The built-in storage battery box is equipped inside the cabinet. For BTS3012A and BTS3006A, it can be configured with two 12 V/100 AH and two 12 V/50 AH batteries respectively. They can supply power to the cabinet for at least 30 and 20 minutes respectively. The extended storage battery cabinet can be optionally configured to extend the power supply time.

7)

It supports the combined cabinet with three cabinets. BTS3012A supports up to 36 TRXs per site, BTS 3006A supports up to 18 TRXs per site. The combined cabinet can meet large-capacity service demands.

8)

Room of standard 19 inches high, 5U wide (5

×

44.45 mm), 300 mm deep is

reserved together with cable outlet for microwave and SDH. Small built-in microwave and SDH transmission equipment can be equipped for diverse demands of the customers.

Caution: The temperature range during which the built-in transmission device of the cabinet can work normally is 0 °C – 55°C.




2.2.3 Smooth Evolution The BTS3X series can support: 

850M, 900M, 1800M, and 1900M services.



Mixed dual band plug-in of 900 MHz and 1800 MHz modules of 6 cells



General packet radio service (GPRS), which helps to realize smooth evolution from 2G to 2.5G systems.

2.2.4 Multiple Transmission Modes 

Multiple built-in transmission modes: 75 ohm/E1, 120 ohm/E1, and SDH. The BTS has powerful transmission adaptability.



Room for transmission equipment such as the built-in microwave and the SDH is reserved in the BTS3012A and BTS3006A. Transmission power is also supplied. Users can select transmission modes according to their demands.

Note: The built-in transmission equipment in the cabinet must meet the requirement of working long time in the environment temperature of 0 oC–55 oC. You can lead out the 24 V DC/220 V DC power supply from the cabinet for the transmission equipment. If it is the 48 V power supply, the transmission power supply module is needed.



Chapter 3 Product Introduction

Chapter 3 Product Introduction 3.1 Cabinet Configuration This section introduces the typical single cabinet configuration of BTS30, BTS312, BTS3006A and BTS3012A. BTS3X adopts a modular RF structure. Clients can configure the boards according to the actual site condition by following certain configuration rule.

3.1.1 BTS30 BTS30 dimensions: 1,600 mm (H) × 600 mm (W) × 450 mm (D) Figure 1.1 shows a typical single BTS30 cabinet under full configuration. In the figure, BTS30 is configured with 3 CDUs, 6 TRXs, 4 power supply units (PSUs), 1 power monitor unit (PMU), 2 timing/transmission and management units (TMUs), 1 transmission extension power supply unit (TES) and 1 transmission extension unit (TEU).




Switch Box

RX

RX

RX

TX

TX

CDU

CDU

TX

TX

TX

RX

RX

RX

TX

CDU

TX

RX

TX

RX

TX

RX

TRXTRX TRXTRXTR X TRX

Fan Box

P

P

P

P

P

T T T T

S

S

S

S

M

MM E E

U

U

U

U U

UU S U

Air Inlet

Figure 1.1 Typical configuration of BTS30

3.1.2 BTS312 BTS312 Dimensions: 1,880 mm (H) × 650 mm (W) × 500 mm (D) Figure 1.1 shows a typical single BTS3012 cabinet under full configuration. In the figure, BTS312 is configured with 6 CDUs, 12 TRXs, 6 PSUs, 1 PMU, 2 TMUs, 1 TES and 2 TEUs.




Switch Box Fan Box

TX RX

TX

TX

TX

RX

RX TX

RX

RX

RX

TX

CDU

CDU

TRXTRXTR XTRX

Air Trough

TX RX

TX

TX

TX

RX

RX TX

RX

RX

RX

TX

CDU

CDU

TRXTRXTR XTRX

Fan Box

Fan Box

TX RX

TX

TX

TX

RX

RX TX

RX

RX

RX

TX

CDU

CDU

TRXTRXTR XTRX

P

P

P

P

P

P

P

T T T T T

S

S

S

S

S

S

M

MMEE E

U

U

U

U

U

U U

UU S UU

Air Inlet

Figure 1.1 Typical configuration of BTS312

3.1.3 BTS3006A BTS3006A dimensions: 1,700 mm (H) × 900 mm (W) ×720 mm (D) BTS3006A can be configured with 3 CDUs, 6 TRXs, 5 PSUs, 1 PMU, 1 TCU, 1 TMU Huawei Technologies Proprietary 3



and 1 Abis bypass board (ABB) and other auxiliary equipment, including transmission equipment, power lightning protection filter box in the left of the cabinet, AC/DC power distribution box, transmission supply unit (TSU) and the built-in battery box.

Switch box Transmission T device S subrack U C D U

C D U

C D U

PMU PSU

EMU

PSU PSU PSU

IPU

PSU AC power distribution subrack

T R X

T R X

T R X

Lightning filter box Battery cable inlet

T R X

T R X

T R X

FMU DC power distribution subrack Lightning protection subrack

Battery cabin

T C U

T A MB UB

Air inlet

Figure 1.1 Typical configuration of BTS3006A

In addition, BTS3006A can be configured with large capacity extended battery cabinet. It can hold 12 batteries with nominal voltage of 2 V. The appearance of the cabinet is shown in Figure 1.2.




Figure 1.2 Appearance of storage battery cabinet without front door

3.1.4 BTS3012A BTS3012A dimensions: 1,700 mm (H) × 1,200 mm (W) × 1000 mm (D) Figure 1.1 shows a typical single BTS3012A cabinet under full configuration. As shown in the figure, the cabinet is configured with 6 CDUs, 12 TRXs, 6 PSUs, 1 PMU, 1 TMU, 1 TCU and 1 Abis bypass board (ABB). The auxiliary equipment cabinet can be configured with transmission device, power lightning protection filter box at cabinet back, AC and DC power distribution boxes, voltage regulator, EMUA, transmission supply unit (TSU), and built-in storage battery box.




Switch Box

E M U A

Transmission device subrack

T S U

FAN Cable Inlet

E1 lightning protection subrack

P S U

P P S S U U

P S U

P P S S U U

P P S M U U

C D U

C D U

T T T T R R R R X X X X

C D

C D U


U

FAN AC power distribution subrack DC power distribution subrack

Battery Cabin

T C U

T A M B U B

FAN

C D U

Cable Inlet

FAN

C D U


Figure 1.1 Typical configuration of BTS3012A

The BTS3012A can also be configured with a large-capacity extended storage battery cabinet, which can accommodate 12 (or 24) storage batteries with the nominal voltage of 2 V.

3.2 BTS3X System Architecture BTS3X supports the following functions: 

Connecting with the base station controller (BSC) via the Abis interface to coordinate with BSC in radio resource management, radio parameter management and interface management




Communicating with the mobile station (MS) via the Um interface to realize radio transmission and related control between BTS and MS

Figure 1.1 shows the system architecture of BTS30/312 equipped with TEU and TES. External Alarm

Abis

Um

TDU

CBUS/TBUS/DBUS

ABB&ABA

TRX

TTA

TTA

TTA

TTA

TTA

TTA

CDU FHBU S

BSC

E1

TMU TRX

Fiber(Optinal)

PSU

TEU

CDU

TES

PMU

TRX

FMU

PBU

Common Unit

ECDU

Signaling Processor Unit

Antenna Feeder Unit

Figure 1.1 BTS30/312 system architecture

The following further explains the above figure: 1)

The boards indicated by dotted blocks are optional:



There are 2 TMU slots on BTS30/BTS312 working in active/standby mode. The standby TMU can be configured as required.



TEU and TES, if configured, provide built-in optical transmission. ABB and Abis bypass assistant board (ABA), if configured, provide the Abis bypass function. Because ABB and ABA must be installed in the slots hosting TEU and TES, you have to select one of the two functions.



Generally, the triplex TTA is adopted.

2)

To meet the requirements in multiple frequency bands and coverage, there are many types of combining and distribution units, including CDU, ECDU, enhanced duplexer unit (EDU), railway GSM enhanced combining and distribution unit (RCDU), railway enhanced duplexer unit (REDU), multi distribution unit (MDU), simple combining unit (SCU), and enhanced simple combining unit (ESCU).

3)

The PBU only supports the power amplification of 40 W TRX at GSM900 MHz and GSM1800 MHz.

4)

TEU is the generic term for boards realizing multiple optical transmission modes. It includes boards access SDH unit (ASU) and passive transmission board (PAT) that provide 155 M SDH and passive optical transmission respectively.

5)

The system architecture of BTS3012A and BTS3006A is similar to that of BTS30/BTS312. They only differ in the architecture of common subsystem. Figure 5.1 shows the logical architecture of the common subsystem when an ABB is installed. For the BTS3012A and BTS3006A, the ABB is optional, while Huawei Technologies Proprietary 7



no TEU, TES, ABA or standby TMU can be configured in the cabinet. Abis

TMU

E1

ABB

PMU

PSU

FMU

Common subsystem

Figure 5.1 Architecture of common subsystem in BTS3012A/BTS3006A

Note: The Abis transmission bypass function can be performed in BTS chain networking environment: 

When the site (excluding the last level) adopting ABB is powered down, ABB is responsible to bypass the site on the Abis transmission line so as to keep the working of other sites on the Abis transmission line normal.



When ABB is located in the last level site of the chain networking environment, if the site is powered down, ABB is responsible to loop back the Abis transmission line.

The BTS3X series of BTS are composed of the following subsystems:

I. Common Subsystem The common subsystem is composed of boards such as TMU, PSU and PMU. It performs the following functions: 

Managing and controlling other subsystems and modules



Collecting alarm information



Providing multiple basic clocks for other subsystems and modules Huawei Technologies Proprietary 8



Communicating with the O&M system



Processing signaling managing resources



Supplying power to the integrated equipment and providing power monitoring and management



Providing multiple built-in transmission interfaces

II. Signal Processing Subsystem The signal processing subsystem is composed of TRXs, PBUs and CDUs. It performs the following functions: 

Channel encoding and decoding, interleaving and de-interleaving



Speech encryption and decryption



Rate adaptation



Mapping between logical channel and radio channel



Inter-cell handover and intra-cell handover



Signal up/down convert, sampling, filtering and amplification

III. Antenna and Feeder Subsystem The antenna and feeder subsystem is composed of antennas, feeders, jumpers, lightning arrester and TTA (optional). It performs the following functions: 

Transmitting RF signals



Receiving signals from MS

 

Amplifying uplink signals received Preventing damage to the equipment by lightning current

3.3 Board Description Table Refer to Table 1.1 for the board description table of BTS3X. Table 1.1 Board description table of BTS3X Board abbreviation

Full name

ABA

Abis Bypass Assistant Board

ABB

Abis Bypass Board

ASU

Access SDH Unit

CDU

Combining and Distribution Unit

ECDU

Enhanced Combining and Distribution Unit

EDU

Enhanced Duplexer Unit




Board abbreviation

Full name

EMU

Environment Monitor Module

EMUA

Environment Monitoring Unit Analyzer

ESCU

Enhanced Simple Combining Unit

MDU

Multi Combining and Distribution Unit

PAT

Passive Transmission Board

PBU

Power Boost Unit

PMU

Power Monitor Unit

PSU

Power Supply Unit

RCDU

Railway GSM Enhanced Combining and Distribution Unit

REDU

RGSM Enhanced Duplexer Unit

SCU

Simple Combining Unit

TCU

Temperature Control Unit

TDU

Time Distribution Unit

TEU

Transmission Extension Unit

TES

Transmission Extension Power Supply Unit

TMU

Timing/Transmission and Management Unit

TRX

Transceiver Unit



Chapter 4 Functions

Chapter 4 Functions 4.1 Basic Functions This section describes the basic functions of the BTS3X series.

4.1.1 Basic Software Functions The basic software functions of the BTS3X series include: 

850M, 900M, 1800M, 1900M services



EGSM, RGSM extended frequency service



All data services prescribed in Phase II+



GPRS basic services



EDGE basic services, MSC1– MSC9 coding and encoding schemes



Support of Phase I/Phase II /Phase II+ compatible LAPDm protocols



CS-1/CS-2/CS-3/CS-4 radio channel coding schemes



Phase I/Phase II/ Phase II+ compatible system information broadcasting and resource indication



Full rate (FR), enhanced full rate (EFR), half rate (HR) data services, adaptive multirate (AMR) services, and all the other types of FR data services



Broadcasting short messages and point-to-point short messages



Paging queue



A5/1, A5/2 encryption/decryption



Basic data dynamic configuration



Dynamic resource management



Measurement report preprocessing



10:1, 12:1 and 15:1 signaling multiplexing on the Abis interface



BCCH frequency mutual-aid



Immediate assignment combination, paging combination and paging resend functions, boosting the radio channel utilization



Voice activity detection (VAD) based discontinuous transmission (DTX) and discontinuous reception (DRX)



Omnidirectional cell and directional cell



Chain, tree, star and ring networking modes supported



Support of locked, fast pull-in, holdover and free run clock modes



Synchronous, asynchronous and quasi-synchronous handover



Um interface tracing and internal interface tracing



Remote and local loading of software Huawei Technologies Proprietary 1


Chapter 4 Functions



Dynamic and static power control



Support of satellite transmission and support of 16 k signaling transmission on the Abis interface



Support of extended cell functions



Uplink frequency scanning



Support of Huawei power control algorithm II



Multi-cell configuration with up to 12 cells



Timeslot-based baseband frequency hopping and RF hopping



Support of class 3 handsets with large power



Support Adaptive Multi-Rate (AMR), support AMR FR and AMR HR

4.1.2 Basic Hardware Functions Basic hardware functions of BTS3X series include: 

Eight E1 ports and twelve antenna feeders ports



Support of battery management



Support of both 900 MHz and 1800 MHz modules in one cell, in total for 6 cells



Lightning protection at trunk ports, power ports, and RF ports



E1 bypass function after the power-off of the BTS3X



BTS3X bar code report and software/hardware version report of some boards



The TMU auto-check of the central frequency of the crystal oscillator



Clock backup and switchover of master and slave clocks



Clock fast pull-in mode



E1 self-loop test and RF self-loop test

4.2 Networking Functions BTS3X has flexible networking modes. It can support multiple transmission modes: E1, SDH, HDSL, microwave and satellite transmission.

4.2.1 E1 Networking When networked via E1, BTS3X supports star, tree and chain networking. E1 networking is shown in IFigure 1.1, IIFigure 1.1, and IIIFigure 1.1, where each line indicates a bi-directional E1 line.


Chapter 4 Functions


I. Star Networking

BTS

BSC

BTS

BTS

Figure 1.1 BTS3X E1 star networking

II. Tree Networking

BTS

BTS

BTS BSC

BTS

Figure 1.1 BTS3X E1 tree networking

III. Chain Networking

BSC

BTS

BTS

Figure 1.1 BTS3X E1 chain networking


BTS

Chapter 4 Functions


IV. Ring Networking

BSC

BTS

BTS

BTS

Figure 1.1 BTS3X E1 chain networking

4.2.2 SDH Networking When networked via SDH, BTS3X supports chain and ring networking. SDH networking is shown in IFigure 1.1 and IIFigure 1.1, where each line indicates an E1, and each pair of lines indicates a pair of optical fibers.

I. Chain Networking

Figure 1.1 BTS3X SDH chain networking

II. Ring Networking

Figure 1.1 BTS3X SDH ring networking

4.2.3 Satellite Transmission Networking In areas lacking transportation facilities, ordinary BTS cannot satisfy the requirements due to restriction of conventional transmission technology. Therefore, GSM services cannot be provided. Adopting the satellite transmission networking mode in these areas will make the transmission effective and economic. Figure 1.1 shows the satellite transmission networking.



Chapter 4 Functions

Figure 1.1 Satellite networking

Technological difficulties of satellite transmission networking are related to the inherent characteristics of satellite transmission, such as long transmission delay, low stability of transmission link, etc. To solve these problems, Huawei adopts delay, synchronization and bit error solutions to guarantee the service quality of satellite transmission.

4.3 Radio Network Functions 4.3.1 Channels Supported I. Channel Types Supported 

TCH/AFS: Advanced Full rate Speech Traffic Channel



TCH/AHS: Advanced Half rate Speech Traffic Channel



TCH/EFS: Enhanced Full rate Speech Traffic Channel



TCH/FS: Full rate Speech Traffic Channel



TCH/HS: Half rate traffic channel for speech



TCH/F9.6: Full rate 9.6kbit/s Traffic Channel



TCH/F4.8: Full rate 4.8kbit/s Traffic Channel



TCH/F2.4: Full rate ≤2.4kbit/s Traffic Channel



PDTCH/F: Full rate packet data traffic channel



FCCH: Frequency Correction Channel



SCH: Synchronization Channel



BCCH: Broadcast Control Channel



PCH: Paging Channel



RACH: Random Access Channel

Chapter 4 Functions



AGCH: Access Grant Channel



PPCH: Packet Paging channel



PRACH: Packet Random access channel



PRAGCH: Packet Access grant channel



PTCCH: Packet Timing advance control channel



SDCCH/8: Stand-alone Dedicated Control Channel, eight of them mapped on a separate basic physical channel



SACCH/C8: Slow SDCCH/8 Associated Control Channel



SACCH/TF: Slow TCH/F Associated Control Channel



FACCH/F: Full rate Fast Associated Control Channel



SDCCH/4: Stand-alone Dedicated Control Channel, four of them mapped on the same basic physical channel as the CCCH



SACCH/C4: Slow, SDCCH/4 Associated Control Channel



CBCH: Cell Broadcast Channel

II. Channel Combinations Supported 

TCH/F + FACCH/F + SACCH/TF



TCH/H(0,1) + FACCH/H(0,1) + SACCH/TH(0,1)



TCH/H(0,0) + FACCH/H(0,1) + SACCH/TH(0,1) + TCH/H(1,1)



FCCH+SCH+BCCH+CCCH



FCCH+SCH+BCCH+CCCH+SDCCH/4+SACCH/C4



BCCH+CCCH



SDCCH/8+SACCH/8



SDCCH/8+SACCH/8+CBCH



FCCH+SCH+BCCH+CCCH+SDCCH/4+SACCH/C4+CBCH



PBCCH+PCCCH+PDTCH+PACCH+PTCCH



PCCCH+PDTCH+PACCH+PTCCH



PDTCH+PACCH+PTCCH

Note: CCCH=PCH+RACH+AGCH PCCCH=PPCH+PRACH+PAGCH

4.3.2 Diversity Receiving A radio channel is a random time-variable channel with fading features. The diversity Huawei Technologies Proprietary 6


Chapter 4 Functions

receiving technology is an effective anti-fading technology. Radio signals that are transmitted to the receiver through radio channels are combination of various multipath components. These signals carry the same message and features irrelevant random fading characteristics. With the diversity receiving technology, these signals can be combined into general receiving signals to diminish the impact caused by fading. The diversity receiving methods include frequency diversity,

time diversity,

polarization diversity and space diversity. BTS3X uses polarization diversity, space diversity and frequency diversity to diminish signal fading.

4.3.3 Frequency Hopping Frequency hopping is an important method to improve the performance of a BTS. It can improve the anti-fading capability of uplink and downlink channels, and can improve the security in communications. BTS3X can provide baseband frequency hopping and RF hopping. RF hopping adopts dynamic loop bandwidth technology and pingpong handover technology to realize realtime switchover between two frequency synthesizers. When frequency hopping is not performed, one channel of the transceiver local oscillator is reserved to raise system reliability.

4.3.4 Power Control When the distance between the MS and BTS3X changes, the BSC adjusts the transmit power of BTS3X accordingly. Each level of power control adopts the automatic power control (APC) technology to minimize the power error at each level. When the timeslot is idle, the BSC will command BTS3X to close the transmit power of the timeslot because there is no downlink signal. Power control can raise the efficiency of the transmitter and the reliability of power amplifier, and minimize the interference of the transmitter. There are 11 BTS3X static power levels: level 0 to 10, descending with 2 dB per level. The maximum output power of BTS is level 0. For example, in the case the maximum output power of BTS30 is 40 W, level 0 corresponds to 46 dBm, while level 10 corresponds to 26 dBm. BTS dynamic power control is fine-tune based on static power control. There are 15 BTS3X dynamic power control levels: level 0 to 15, in descending sequence, where level 0 is the same as that of static power control level. If the "current maximum transmit power" is Pm, the range of dynamic power control is Pm to (Pm - 30) dBm. When dynamic power control reaches the maximum but still cannot meet the



Chapter 4 Functions

requirement, the static power control should be adjusted so as to raise the maximum output power of dynamic power control.

4.3.5 Discontinuous Transmission There are two transmission modes in the GSM system: 

One is the normal mode, in which noise has the same transmission quality as voice.



The other is discontinuous transmission (DTX) mode, in which MS only sends the encoded background noise that is called "comfortable noise".

The utilization of DTX can meet the requirement for system measurement and can make the called feel that the call is not disconnected. BTS3X adopts voice activation detection (VAD) technology to distinguish voice from noise.

4.3.6 AMR BTS3X supports Adaptive Multi Rate (AMR). AMR is a set of multiple voice Codec algorithms. Different Codec algorithm generates different rate voice code stream. The BTS and MS can automatically choose a proper Codec algorithm according to the actual radio environment to adjust the rate. Thus the voice quality of the radio communication system is improved.



Chapter 5 Reliability Design

Chapter 5 Reliability Design 5.1 System Reliability Design I. Rating-Lowering Design The strict rating-lowering design is applied to power and easily overheated devices to make the electrical stress and temperature stress in practical utilization lower than the set rating. This postpones the degradation of parameters and prolongs their life span.

II. Heat Design Through parts selection, circuit design, structure design, and heat dissipation design, the impact of temperature change on product performance is reduced and reliable operation of the product in a wider temperature range is ensured.

III. EMC Design Electromagnetic compatibility (EMC) design prevents equipment from inhibited degradation caused by electromagnetic transmission of other equipment in the same electromagnetic environment. It also prevents other equipment, subsystems, and systems in the same electromagnetic environment from inhibited degradation caused by the electromagnetic transmission of the equipment.

IV. System Fault Monitoring and Handling The system can auto-test and diagnose software and hardware fault, and report alarms. It can record and output the fault records for print. It collects environment conditions and report alarms when it detects problems. When TMU is faulty, the system can test the major faults and report alarms while keeping the communication between BTS and BSC.

V. System Fault Protection A fault of any module will not lead to destructive fault of other modules. Major faults can be reported in time.

VI. System Maintainability Design Reasonable BTS internal cabling facilitates board replacement during fault handling.




During board replacement, you can only disconnect the cables of the faulty boards. When replacing boards, main boards can be plugged in or pulled out from the front of the cabinet. By indicator states, you can judge whether the equipment operation is normal.

VII. Running Environment Protection Design The system provides the following functions for the PSU and the transmit power equipment: 

Input over- and under-voltage protection



Output over-voltage protection



Output short-circuited protection



Output overload protection



Excess temperature protection

For the DC input transmit power, it has input reverse polarity protection to guarantee system safety.

5.2 Hardware Reliability Design 5.2.1 Board Coding Key Design When a functional board is mistakenly inserted into the slot of the functional board of another kind, the mistakenly inserted board cannot make normal contact with the backplane. The coding key is adopted to protect the equipment against damage.

5.2.2 Power System Reliability Design I. Uninterrupted Power Supply Design For BTS using AC power supply, the outdoor BTS can work for some time by using the storage battery equipped to keep the operation of equipment during this time when external mains supply is powered off. The BTS sends mains supply power off alarm signal to the BAM in the meantime, and handles the alarm according to the actual situation. BTS3006A/BTS3012A has built-in transmit power to provide -48 V power for transmission equipment. To improve reliability, 1+1 backup working mode may be adopted for the transmit power. When one of the modules is faulty, it automatically exits the power supply system, while another module provides output to all -48V load and sends the module faulty alarm information to the BAM.




II. Distributed Power Supply Design Distributed power supply for load is adopted inside the system. The key power supply path, AC/DC part, adopts N+1 backup working mode. If one of the modules in AC/DC part is faulty, alarm information can be sent to the BAM, and onsite hot swappable replacement is supported.

5.2.3 Abis Communication Bypass Design When BTS is in chain networking environment and its power fails, the Abis transmission bypass board in the BTS can bypass the transmission line of the TMU board internally, hence avoiding long-time service disruption of all the sites under this BTS.

5.3 Software Reliability Design I. Scheduled Check of Key Resources For software resources in the system, the verifying mechanism for long-time occupation is applied among the modules. In case of resources unavailable due to software exception, the verifying mechanism can ensure the release of unavailable resources and the output of various logs and alarms.

II. Fault Isolation Feature Software design features module fault isolation. The error in some software module is only restricted in the module and does not lead to fault in other software modules. The software can tolerate faults and correct errors. Abnormal operation of minor software does not cause system restart or reset.

III. Data Check 

Consistency check of user input data guarantees the correctness of reference relation among the data.



When the system detects data modification failure in some stage, it will restore the related data to the initial state for data consistency.

IV. Process Monitoring During software operations, output channels are provided for internal software errors and part of hardware errors, which is defined as the process monitoring mechanism. This mechanism can monitor the running state of tasks, handle system abnormalities and report to the external devices.


Chapter 6 O&M System


Chapter 6 O&M System 6.1 O&M Architecture 6.1.1 Overview As shown in Figure 1.1, BTS can provide two maintenance modes: 

Local maintenance



Remote maintenance

OMC Server

MMI Local Maintenance Console

A b i s

BTS i s A b

MMI

Remote Maintenance Console

BSC Remote Maintenance Console

BTS

Hub

Figure 1.1 BTS O&M structure

6.1.2 Local Maintenance Local maintenance refers to the maintenance mode in which PCs are connected to BTS through serial port cables and implement maintenance operations to the BTS, as shown in 6.1.1 IFigure 1.1. The local maintenance console can only be accessed after the local maintenance software is loaded to PCs. The BTS local maintenance is carried out based on different logical objects of the BTS, including site, cell, carrier, and baseband. Direct operations can also be performed on boards. Real-time alarm messages can be obtained at the same time.

6.1.3 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, as Huawei Technologies Proprietary 1



shown in 6.1.1 IFigure 1.1. The remote maintenance console can only be accessed via OMC Shell of the workstation (WS). The user interface of the BTS remote maintenance console uses 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. You can specify an NE to be maintained and check its detailed performance data, alarm data and configuration data. You can also implement operations and maintenance on certain types of NEs through the topological map.

6.2 O&M Functions The BTS3X O&M system provides powerful O&M functions to meet your requirements in equipment performance and maintenance. These functions include:  

Security management Alarm management



Maintenance management



Performance measurement and test

6.2.1 Security Management Various remote maintenance operations can be implemented through the O&M system. The system provides powerful security management to execute O&M control over the equipment in order to avoid unauthorized operations that may affect normal performance of the equipment. To perform operations and maintenance on the BTS, you have to log in and go through authentication. The system provides an authorization system on 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 get confirmation for the potential problems due to the operations.

6.2.2 Alarm Management The BTS 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, and analyzing. Besides, it provides an on-line help information system and stage filtering system to help you quickly locate faults. It also provides alarm recovery methods.




6.2.3 Maintenance Management The operation & maintenance center (OMC) implements management over the whole BSS through BSC. For the OMC, the BTS is highly visible. BTS can check and locate internal errors so that BSC can implement maintenance to it without knowing the internal structure of each BTS.

6.2.4 Performance Measurement and Test The O&M system can implement performance measurement and test to the entities so as to collect BTS running states data and perform accurate analysis on the running states.


Chapter 7 Technical Specifications


Chapter 7 Technical Specifications 7.1 Engineering Specifications of BTS3X Cabinet The cabinet engineering specifications of BTS30 are shown in Table 1.1. Table 1.1 BTS30 cabinet engineering specifications Parameter Cabinet dimensions

Specifications Height

1600 mm

Width

600 mm

Depth

450 mm

Weight

180 kg (a single cabinet under full configuration)

Power consumption

1200 W (a single cabinet under full configuration)

Working environment

-5C to +45C

temperature Working environment relative

15% to 85%

humidity Frequency: 1.3  107 Hz, with precision higher than

Clock

0.05 ppm at delivery Temperature drift: < 5  10-8 (0C to 70C) Annual aging rate:< 1  10-7 Input power supply

220 V AC: 150 V AC to 280 V AC/47 Hz to 63 Hz -48 V DC: –40 V DC to -60 V DC 24 V DC: 19 V DC to 29 V DC

Security performance

In compliance with IEC60950 standard

Earthquake-proof

In compliance with IEC Class 4M3 standard

performance EMC

In compliance with ETS 300-342-3 corresponding standard Huawei Technologies Proprietary 1



The cabinet engineering specifications of BTS312 are shown in Table 1.2. Table 1.2 BTS312 cabinet engineering specifications Parameter Cabinet dimensions

Specifications Height

1880 mm

Width

650 mm

Depth

500 mm

Weight

330 kg (a single cabinet under full configuration)

Power consumption

2400 W (a single cabinet under full configuration)

Working environment

-5C to +45C

temperature Working environment

15% to 85%

relative humidity Clock

Frequency: 1.3  107 Hz, with precision higher than 0.05 ppm at delivery Temperature drift: < 5  10-8 (0C to 70C) Annual aging rate:< 1  10-7

Input power

220 V AC: 150 V AC to 280 V AC/47 Hz to 63 Hz. -48 V DC -40 V DC to -60 V DC 24 V DC: 19 V DC to 29 V DC

Security


Earthquake-proof


performance EMC

In compliance with ETS 300-342-3 related standard

The cabinet engineering specifications of BTS3006A are shown in Table 1.3.




Table 1.3 BTS3006A cabinet engineering specifications Parameter

Specifications

Cabinet dimensions

Weight

Height

1700 mm

Width

900 mm

Depth

720 mm

390 kg (a single cabinet under full configuration, including built-in batteries) 250 kg (assembly cabinet)

Power consumption

1900W (when the heat exchanger is not working) 2300W (when the heat exchanger is exchanging the heat) 3500W (when the heat exchanger is heating the cabinet)

Working environment

-40C – +50C

temperature Storage temperature

-40 C – +70C

Working environment

5% – 100%

relative humidity Clock

Frequency: 1.3  107Hz, with precision at delivery higher than 0.05 ppm Temperature drift: < ±5  10-8(0C to 70C) Annual aging rate: <±1  10-7

Input power

220V AC voltage range: 176 V – 275 V; (150 V – 176 V or 275 V – 300 V). Working frequency: 45 Hz – 65Hz; 220V AC supports single phase or three-phase power supply. 110V AC voltage range: 90 V – 135 V Working frequency: 45 Hz– 65Hz; 110V AC only supports double live line power supply.

Security

In compliance with IEC60950 standard Huawei Technologies Proprietary 3



Parameter

Specifications

Earthquake-proof


performance EMC


Waterproof and dustproof

In compliance with IP55 standard

performance

The cabinet engineering specifications of BTS3012A are shown in Table 1.4. Table 1.4 BTS3012A cabinet engineering specifications Parameter

Specifications

Cabinet dimensions

Weight

Height

1700 mm

Width

1200 mm

Depth

1000 mm

650 kg (a single cabinet under full configuration, including storage batteries) 420 kg (assembly cabinet)

Power consumption

Power consumption of a full configuration cabinet: 

3500 W (when the air conditioner/the heat exchanger is not working)



5500 W (when the air conditioner is cooling the cabinet)



6100 W (when the air conditioner is heating the cabinet)



4150 W (when the heat exchanger is exchanging the heat)



6240 W (when the heat exchanger is heating the cabinet)

Working environment temperature

Cabinet with an air conditioner: -40 C to +55C Cabinet with an heat exchanger: -40 C to +45C Storage battery cabinet: -20 C to +45C




Parameter

Specifications

Startup temperature

BTS3012A can be started at -40 C. The startup time is less than 2 hours after the BTS is heated to -10 C.

Storage temperature

-40 C to +70C

Working environment

5% to 95%

relative humidity Frequency: 1.3  107 Hz, with precision at delivery

Clock

higher than 0.05 ppm Temperature drift: < 5  10-8 (0C to 70C) Annual aging rate:< 1  10-7 Input power

Normal working voltage: 90 V AC to 276 V AC/47 Hz to 53 Hz Tolerant voltage: 300V AC

Security


Earthquake-proof


performance EMC


Waterproof and dustproof

In compliance with IP55 standard

performance

7.2 Performance Specifications of BTS3X Cabinet The performance specifications of BTS3X cabinet are shown in Table 1.1. Table 1.1 Performance specifications of BTS3X cabinet Performance

Parameter

Specifications

classification System indices

Channel capacity

8CH/TRX




Performance

Parameter

Specifications

classification Frequency band

GSM850: Uplink: 824 MHz to 849 MHz Downlink: 869 MHz to 894 MHz GSM900: Uplink: 890 MHz to 915 MHz Downlink: 935 MHz to 960 MHz GSM1800: Uplink: 1,710 MHz to 1,785 MHz Downlink: 1,805 MHz to1,880 MHz GSM1900: Uplink: 1,850 MHz to 1,910 MHz Downlink: 1,930 MHz to1,990 MHz

RGSM: Uplink: 876 MHz to 915 MHz Downlink: 921 MHz to 960 MHz Receiving

Static receive

performance

sensitivity

GSM850: -110dBm GSM900: -110dBm GSM1800: -109dBm GSM1900: -109dBm RGSM: -110dBm

Block feature

Satisfies requirement of GSM11.21 protocol

Anti-interference


feature Intermodulation


suppression




Performance

Parameter

Specifications

classification Stray radiation


Transmitting

Maximum transmit

40W TRX: 46.0 dBm

performance

power of each

60W TRX: 47.8 dBm

TRX

40W TRX + PBU: 49.0 dBm ETR: 46.0 dBm (8PSK)/47.8 dBm (GMSK) Absolute transmit power precision



2  0.5 dB (temperature within normal

range) 

2  1 dB (temperature out of normal

range) Static power

Level 0 to 10

control range Dynamic power

Level 0 to 15

control range Transmit spectrum


Intermodulation


suppression Stray radiation


Frequency error



0.05 ppm

Phase error



5 (rms)



20 (peak)

7.3 External Physical Interfaces The external physical interfaces of BTS30 and BTS312 are shown in Table 1.1.




Table 1.1 External physical interfaces of BTS30 and BTS312 Interface Abis interface

Type

Quantity

E1

8 pairs

Function realized 

Provides 75 ohm/120 ohm E1 interface



Supports cascading



Provides O&M link (OML)

STM-1

2 pairs



Provides SDH optical transmission interface

Clock interface (CLK)



Supports cascading



Provides OML

FCLK

1

FCLK test port

13 MCLK

1

13 MHz clock test port

SYNC

1

External synchronization input end (satellite)

Maintenance

MMI Serial

1

interface

port

Power and

Power supply

Provides local maintenance channel

grounding

3 power input modes



-48 VDC input power



+24VDC input power



220 VAC input power

Grounding

1

PGND

RF signal

12

Feeder input port

Combined cabinet

Data bus

2

Data bus interface

interface

interface

Feeder cable interface

DCF1 and DCF2

Clock bus

2

interface

Combined cabinet clock bus interface CKB1 and CKB2

Combined

6

cabinet

CDU combined cabinet cascading interface

cascading interface




Interface Management

Type

Quantity

Alarm


2

External

alarm

interface EAC1 and

signal interface

EAC2 

Can be connected to environment monitor

Storage

1

Connects to storage

battery

power pool signal

management

PWRC

The external physical interfaces of BTS3006A are shown in Table 1.2. Table 1.2 BTS3006A external physical interfaces Interface Abis interface

Type

Quantity

E1

4 pairs


Provides 75 ohm/120 ohm E1 interface

Clock interface



Supports cascading



Provides OML

FCLK

1

FCLK test port

13 MCLK

1

13 MHz clock test port

Maintenance

MMI serial

1

Provides near end maintenance

interface

port

Power and

Power supply

(CLK)

channel 1

grounding

It can be used as the input port for 220 V AC/110V AC power supply.

Feeder cable

PGND

1

1 grounding interface

RF signal

6

Feeder input interface

interface

The external physical interfaces of BTS3012A are shown in Table 1.3.


01 System Description

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