Huawei 3900 Bts

Features and Functions

It shares the BBU, which is the central processing unit, with the BTS3900 to minimize the number of spare parts and reduce the cost.

It can be flexibly installed in a small footprint and can be easily maintained

It supports multiple frequency bands, such as PGSM900, EGSM900, and DCS1800

It supports the GPRS

It supports multiple network topologies, such as star, tree, chain, ring, and hybrid topologies

It supports the cell broadcast SMS and point-to-point SMS.

A single cabinet supports up to 12 carriers in the maximum cell configuration of S4/4/4.

Common Subsystem

(1) BBU Control subsystem whose functions are implemented by the BBU

(2) DRFU RF subsystem whose functions are implemented by the DRFU

(3) DCDU Power subsystem

(4) Fan Box

BTS3900 Cabinet and Boards

BSBC(BBU) Universal BBU Subrack Backplane type C (2U)

UEIU Universal Environment Interface Unit

GTMU GSM Transmission and Management Unit for the BBU

UELP Universal E1/T1 Lightning Protection Unit

UBFA Universal BBU Fan unit type A (2U)

UPEU Universal Power and Environment interface Unit

DRFU Double Radio Filter Unit

DCDU Direct Current Distribution Unit

GATM GSM Antenna and TMA Control Module

Fan box Fan box

Functions of BBU

Provides physical ports between the BTS and the BSC for interaction

Provides the CPRI ports for communication with the DRFU

Provides the USB port for downloading the BTS software

Provides OM channels for connection to the LMT (or M2000)

Processes UL and DL data

Provides centralized management on the entire BTS system, such as OM and signaling processing

Provides the reference clock for the entire system

Functions of BSBC Board

Clock signal: The BSBC sends the precise clock signals provided by the GTMU to each service processing module as reference clock.

Power input: The BSBC distributes the +12 V DC power input provided by the power module to the boards and modules.

Low-speed signal management: The BSBC provides the interface for the GTMU to monitor and manage the service board, power, backplane, and fan.

High-speed signal management: The BSBC distributes and converges information about data, control, and management of all boards in the baseband unit system

Service signal: The BSBC transfers the UL and DL baseband data of the GTMU.

Functions of UBFA Module

Fan control board

(1) Processes the two-channel 12 V power input by the backplane to provide power for the fan

(2) Communicates with the GTMU to control and monitor the fan

(3) Detects and adjusts the fan speed

(4) Detects the board temperature by the built-in temperature sensor

(5)Provides the automatic reset function

Fan: performs forced heat dissipation for the entire BBU

Functions of UPEU Module

Supplies power to the boards, modules, and fans

Introduces environment monitoring signals to the BBU

Reports fault signals, in-position signals, and version information associated with the boards and modules

Function of GTMU Board

Controls, maintains, and operates the BTS

Supports fault management, configuration management, performance management, and security management

Supports the monitoring of the fan module and power supply module

Provides port for terminal maintenance

Supports four E1 inputs

Provides CPRI ports for communication with the RF modules

Functions of DRFU

It implements the direct frequency conversion technique in the transmit channel, modulates the baseband signals to GSM RF signals. After filtering, amplifying, and combining the RF signals, the DRFU sends the signals to the antenna for transmission. The combining can be performed as required.

It receives RF signals from the antenna and performs down-conversion, amplification, analog-to-digital conversion, matched filtering, and Automatic Gain Control (AGC). Then, the DRFU transmits the signals to the BBU for further processing.

It controls power and detects the Voltage Standing Wave Ration (VSWR).