BTSA CARDS INTRODUCTION

BTSA CARDS INTRODUCTIONTABLE OF CONTENTS

1. CCM Module...........................................................................................................2

2. BTS-CDSU Module...............................................................................................2

3. SAM Module...........................................................................................................3

4. CHM.........................................................................................................................3

5. RFIM.........................................................................................................................4

6. TRX...........................................................................................................................5

7. GPSTM....................................................................................................................5

8. TCM..........................................................................................................................5

9. FDM..........................................................................................................................6

10. HPA........................................................................................................................6

11. DUP........................................................................................................................6

12. DIV..........................................................................................................................7

13. COM-DUP.............................................................................................................7

14. COM.......................................................................................................................7

15. PSMD.....................................................................................................................8

16. PPM........................................................................................................................8

17. PSMC.....................................................................................................................8

18. PSMB.....................................................................................................................8

1 CCM MODULEOverviewCCM is in the ZXC10-BTS BDS frame and responsible for centralized control of data signaling route, signaling processing, resource management and maintenance operation in the whole BDS subsystem

Ting. The common the module processing unit of the CCM board is made up of general processor and such peripherals as Flash/BootROM and SDRAM. Flash/BootROM is used to store boot program and application program, and SDRAM is used for the system memory to store software program and temporary data, message queue and database data in the course of system running. The gateway unit is for bus arbitration, data route, bus monitoring and communication with CDSU. The bus interface module is responsible for communication between the module processing unit and gateway unit. The test network interface and serial interface are used for board tesication interface is used for communication with SAM, TCM and FDM boards. The active/standby interface implements active/standby control functions. WATCHDOG is used to monitor the CPU to make sure self-reset signals can be generated when a board fails. LOGIC is for control of board reset logic, active/standby changeover and key chips, and adjustment of key signal timing. The power supply module provides the operating voltage needed by the chips within a board.The CCM board implements the following functions:

1. Signaling processing/transfer.

2. Maintenance management and reporting of wireless channel resource.

3. Management and maintenance of different modules in the BDS subsystem.

4. Maintenance management of GPSTM and reading of TOD messages.5. Software download and data distribution.

2 BTS CDSU MODULEOverviewIn the CDMA system, the interface between BSC and BTS is called an Abis interface. This interface connects BSC and BTS in the form of a daisy chain through the E1 trunk link. CDSU board provides the functions of the Abis interface. BTS-CDSU and BSC-CDSU are basically the same in hardware and operating principles except that BTS-CDSU has a narrower panel.

According to interface capacity, CDSU can be divided into two types of boards: CDSU with 2 E1s and CDSU with 4 E1s

BTS-CDSU implements the following functions:

A. CDSU BOARD HAVING 2 E1S

1) Provides 32-frame cache for each E1.

2) Cache of each E1 supports 4-level flow control.

3) Supports star networking

4) Load sharing and backup of 2 E1s.

B. CDSU BOARD WITH 4 E1

1) Distinguishes the data of each E1 interface in terms of priority. Provides high-priority

data in each channel of data with 500-frame cache space and low-priority data with 1,000-

frame cache space.

2) Supports broadcast data.

3) Supports star networking

4) Supports daisy chain networking.

5) Performs load sharing and backup between E1 links.

6) Provides Abis interface and large HIRS delay test.

7) Provides performance statistics

8) Works as a unit completely compatible with CDSU board with 2 E1s.

3 SAM MODULEOverviewSAM (Site Alarm Module) is in the BDS shelf on BTS side in a base station. It is used to monitor the power supply module, running status of fan and door control, flooding, temperature/humidity, smog and other environment signals. It reports measuring results through CCM to the operation console at the background, where they will be processed. In addition, SAM provides RS232 and RS485 interfaces used to connect external monitoring equipment.

The SAM board functions to:

1. Report actively alarm signals to the CCM board, receive and implement the control

commands from the CCM board;

2 Provide half-duplex RS485 bus and collects power supply and fan alarm signals from

different power supply boards;

3. Provide 2-RS232 interface and 1 full duplex RS485 interface for communication with

external environment monitoring equipment.

4. Provide door control, smog and flooding alarm monitoring;

5. Monitor the humidity, upper/medium/lower points of temperature inside a cabinet and the

temperature/humidity in the equipment room;

6. Provide 4-channel standby input interface and 2-channel standby output interface.

4 CHMOverviewCHM, located in the BDS frame of ZXC10-BTS, is responsible for modulation/demodulation of the channels in CDMA. It is connected with CCM through the receive/transmit bus and connected with RFIM through the baseband data bus. CHM is made up of CPU unit, modulation/demodulation unit, clock distribution unit and receive/transmit bus control unit. A single frame has 6 CHM modules per carrier.

CHM implements the following functions:

1. Provides the receive/transmit interface to communicate with CCM.

2. Forward links modulate voice and data frames sent from CCM through the receive/transmit

interface and send the modulated signals to RFIM.

3. Backward links receive antenna signals distributed from RFIM through the baseband data

interface, convert them into voice and data frame and send them to CCM through the

receive/transmit interface for switching processing.

4. Provides It provides 10MHz ETHERNET interface used for module test and program

download.

5. Provides RS232 interface used for module test.

6. Supports CDMA-2000 physical layer, IS-2000-2 RELASE 0.

7. Supports OTD and STS send diversity.

8. Forward links: including pilot channels (F-PICH, F-TDPICH, F-APICH and F-ATDPICH),

control channels (F-SYNCH, F-PCH, F-BCH, F-QPCH, F-CPCCH, F-CACH and F-CCCH),

and traffic channels (F-DCCH, F-FCH, F-SCH and F-SCCH).

9. Backward links: access channels (R-ACH, R-EACH, R-CCCH). Traffic channel: R-DCCH,

R-FCH, R-SCH and R-SCCH.

10. Supports system hot-plug.

11. Online version download through the receive/transmit bus.

12. Supports system remote soft reset control and backplane interface close control.

13. Drives panel indicators and supports indicator requirements.

5 RFIMOverviewRFIM belongs to Digital Base band (BDS) in BTS. RFIM is connected with the digital subsystem and radio frequency subsystem in BTS.RFIM is connected with CCM through the receive/transmit bus and is controlled by CCM.RFIM transmits and processes forward/backward baseband data and TRX control signaling information (configuration control, status alarm).RFIM board implements the following functions:

1. Forward baseband data processing: receives forward baseband data sent from a channel

board, sums and filters them in terms of different sectors, multiplexes them and sends them

to the TRX unit.

2. Backward base band data processing: receives backward baseband data (multiplexed) sent

from TRX unit. The data is demultiplexed, resynchronized, checked and sent to a channel

board.

3. Functions of the receive/transmit interface: after serial/parallel conversion and cache, the

interface sends serially the distribution bus data to different TRXs according to different

addresses. Then, this interface receives serial signaling data from TRX and after

serial/parallel conversion, cache, check and queuing, the data is sent to CCM through the

convergence bus.

4. Functions of MCU: receive CCM control through the receive/transmit bus, configure this

board, collect and report this board status to CCM.

5. Clock distribution functions: receives 16CHIP clock and PP2S timing pulse sent from GPS

unit and provides them for this board and other channel boards.

6 TRXOverviewTRX is the junction connecting radio frequency and baseband signals. One TRX corresponds to one sector and one carrier. TRX receives the main reception and diversity reception signals from two RFEs within one sector, filters them in mode of down-conversion and intermediate-frequency and implements AGC processing. After that, TRX implements I/Q demodulation to convert the received radio frequency modulation signals into baseband I/Q signals. TRX receives forward baseband I/Q signals and implements I/Q modulation and intermediate-frequency filtering. TRX converts them in mode of up-conversion into radio frequency modulation signals. TRX implements TPTL power control at the same time. TRX is vital in RFS to receive/transmit link signals and process them.

7 GPSTMOverview

In CDMA mobile communication system, synchronization is divided into transmission synchronization and wireless synchronization. Transmission synchronization generally employs master-slave synchronization mode while wireless synchronization in CDMA system employs GPS synchronization. This requires that wireless interfaces in the whole cellular system should be synchronized in a same standard moment. This standard moment is provided by the GPS and synchronizes with Universal Temps Coordine (UTC).In the ZTE CDMA system, the synchronization timing solution requires that BTS synchronizes with BSC at the standard moment signal provided by GPS.GPSTM is the module that provides standard moment signals and relevant system reference for BTS and BSC. It is the key module in the CDMA system.GPSTM provides clocks 16CHIP and PP2S needed in the system for base station baseband digital subsystem, provides 10MHz sine signals as the radio frequency system reference for radio frequency subsystem provide and provides TOD messages for the system.

8 TCMOverviewTCM board belongs to TFS subsystem. The TCM in BTS is located in a TRX shelf while that in BSC is located in a CDSU shelf. The function of TCM is to receive, synthesize and distribute 10MHz of active/standby GPSTM. TCM receives PP2S and 16CHIP of active/standby GPSTM for phase-locking and generates a new PP2S and 16CHIP.TCM, as the signal junction connecting active/standby GPSTMs, makes active/standby GPSTMs maintain the continuity of PP2S and 16CHIP in switchover instead of call drop. In design, the number of reliable elements is decreased as much as possible and circuits are simplified to improve reliability. As heat design and electromagnetic compatibility are taken into consideration, the board reliability is ensured.

9 FDMOverviewFDM board is a TFS subsystem. FDM in BTS is located in the TRX shelf and its functions are as follows: in 800MHz system, FDM receives 10MHz signals from TCM, outputs 12MHz signals in mode of phase-lock and then sends them to 6-channel TRX (in active/standby switchover, 10MHZ signals are discontinuous. After phase-lock buffer, continuous 12MHz signals are output, and no call drop will occur).The FDM board implements the following functions:

1. Receives clock signals from TCM.

2. Distributes 10MHz signals or distributes them after phase-lock. 3. Reports the working status of this board through IIC

10 HPAOverviewThe HPA module is used for power amplification of forward transmitting signals from TRX. After that the signals go through the RFE filter and are transmitted by an antenna towards a cell.When the monitoring circuit detecting any abnormality of running status, it will generate alarms, report and display them on the front panel. It will also implement power amplification close protection. The HPA will generate an alarm in the following cases:

1. When a fault occurs to a component inside the HPA, the HPA will generate “component

failure alarm”.

2. When an antenna feeder or RF cable becomes faulty, the HPA will give an alarm. For

example, when the antenna feeder or RF cable is not tightened and the RF output interface of

the HPA may have an excessively large standing wave coefficient, the HPA will generate

“standing wave alarm”.

3.When the RF signals input at HPA RF input interface have an excessively large amplitude,

which leads to excessively large HPA RF output power, the HPA will generate an “overpower

alarm”.

11 DUPOverviewThe RFE-DUP board is a base station RFE module and plays an important role in implementing receive/transmit functions. With this module, one antenna is enough to receive/transmit RF signals, which is highly cost-effective. It is generally used in frequency division duplex systems. The RFE-DUP is plugged into the RFE shelf of an RFE module.The RFE-DUP implements the following functions:

1. Filters small signals received by an antenna and amplifies them in low noise.

2. Allocates power to the received signals that undergo low noise amplification.

3. Works as a transceiver duplexer.

4. Filters forward transmitting power signals.

12 DIVOverviewThe RFE-DIV board is a base station RFE module and plays an important role in implementing the diversity reception function. The RFE-DIV is plugged into the RFE shelf of an RFE module.The RFE-DIV implements the following functions:



3. Detects the low-noise amplifier status.

13 COM-DUPOverview

The RFE-COM-DUP board is a base station RFE module and plays an important role in implement receive/transmit functions. With this module, one antenna is enough to receive/transmit RF signals, which is highly cost-effective. It is generally used in frequency division duplex systems. The RFE-COM-DUP is plugged into the RFE shelf of an RFE moduleThe RFE-COM-DUP implements the following functions:



3. Works as a transceiver duplexer.

4. Filters forward transmitting power signals.

5. Detects the low-noise amplifier status.

14 COMOverview

The RFE-COM board belongs to the base station the RFE module and is an important module implementing combined transmission function when there are 3 carriers or 4 carriers in each sector.

15 PSMDOverviewPSMD is located in the BTS power distribution shelf

PSMD distributes one-channel input -48V DC to different shelves. PSMD board detects and controls the working status of the power supply system and fans. PSMD provides one RS485 interface to communicate with SAM board.

16 PPMOverviewPPM is located in the power supply layer shelf in BTS and provides 27V DC power supply for the RF subsystem.PPM provides 27V DC for the RF subsystem. PPM employs N+1 backup mode. PPM single power supply rectifier implements the conversion between -48V DC and 27V DC, output over-voltage/over-current protection and power component excess temperature protection, and employs the heat sink structure of temperature-sensing forced air cooling. PPM is capable of parallel load sharing functions and can satisfy flow equalization indexes even when there are 5 modules. Input adopts pre-charge soft start measures to ensure a very small start surge current. Output employs diode isolation to prevent back flow; therefore hot-plug is possible.

17 PSMCOverviewPSMC is located in the power supply layer shelf in BTS and provides ± 12V power supply.PSMC is used to provide ±12V power supply. The DC/DC conversion module works as the core, together with peripheral circuits such as protection circuits, filter circuits and detection circuits. The power supply conversion board from -48V to 12V is formed and works in a stable and reliable way.

18 PSMBOverviewThe power board (PSMB) is located in the BDS shelf in BTS and powers the digital system. To ensure reliable running, the power supply inside the shelf works in the mode of peer backup. Normally, two power supply modules provide power supply in parallel. When one of them is faulty, the other will power the whole shelf. In addition, the PSMB board will report its own working status to the system monitoring unit. It provides a 485 interface for communication.Power board PSMB powers the digital system. To ensure reliable running, the power supply inside the shelf works in the mode of peer backup. Normally, two power supply modules provide power supply in parallel. When one of them is faulty, the other will power the whole shelf. In addition, the PSMB board will report its own working status to the system monitoring unit. It provides a 485 interface for communication.

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BTSA CARDS INTRODUCTION