 Like a server cabinet
 The BTS3012 cabinet is purple gray in
color and vertical in appearance

1.
2.
3.
4.
5.
6.
7.
8.
The components are
Transmission subrack
Common subrack
DTRU subrack -0
Fan subrack
DTRU subrack-1
DAFU subrack
Power distribution unit
Signal lightning protection subrack
located below the common sub-rack.
 Reserves space for the baseband unit
(BBU).

› Such as SDH,
› microwave transmission equipment
Common subrack
 The common subrack is installed below the
fan subrack. It holds the following parts:

› DTMU
› DEMU
› DATU
› DCSU
› DCCU
› DABB
› DPTU
Dual Transmission or Timing Management
Unit
 an entity for basic transmission and
control in the BTS3012.
 It works as a main controller.
 The DTMU is a mandatory module
inserted in slots 0 and 1 (from left to right)

Dual Environment Monitoring Unit
 The DEMU performs the following
functions:

› Monitors the environment information sent
from the smoke sensor, water sensor,
temperature and humidity sensor, infrared
sensor, and door control sensor
› Collects alarm information and reports it to
the DTMU

Dual Antenna and TMA Control Unit
Controls the RET antenna
 Feeds power to the TMA

Combined cabinet Signal connection Unit is
placed in slot 5 of the common sub-rack
 The DCSU is a mandatory board
 The DCSU performs the following functions:

› Transmits clock signals, data signals, and control
signals between the main cabinet and the
extension cabinet
› Transmits the clock signals, data signals, and
control signals from the DTMU to the DTRU
Cable Connection Unit is placed in slot 6.
 The DCCU is a mandatory board.
 The DCCU performs the following
functions:

› Transfers E1 signals
› Transfers the control signals for the fans
› Transfers the clock signals from the DAFU
subrack
Packet transmission unit can be installed
in slot 3 or 4
 The DPTU is mandatory
 The DPTU performs the following
functions:

› Provides the interface for Abis over IP
› Provides the BTS with the convergence
function of a Hub
› Provides the functionality of Clock Over IP

The DTRU subracks can hold up to nine
DTRUs



Double-Transceiver Unit (DTRU) is placed in the
double-transceiver subsystem of the BTS.
One DTRU consists of two TRXs
Baseband Processing Part
› The baseband processing part performs the following
functions:
› Processing signaling, coding and decoding,
interleaving and de-interleaving, modulation and
demodulation
› Supports RF loop test and switchover of the faulty
phase-locked loop
› Amplifying output power

RF Transmitting Part
› The transmitting part of the RF signals performs the
following functions:
› Modulates the baseband signals into RF signals and
performs up-conversion, filtering, and RF hopping
› Amplifies and outputs the RF signals

RF Receiving Part
› The receiving part of the RF signals performs the
following functions:
› Demodulates the RF signals into baseband signals
and performs RF hopping
› Divides the received RF signals and performs receive
diversity
The fan subrack holds one fan box
 a fan monitoring board consists of four fans.
 The fan monitoring board detects the
temperature at air inlets at bottom of the
cabinet and automatically adjusts the fan
speed

Antenna Front-end Unit
 The DAFU subrack can be configured
with

› DDPU
› DCOM
› DFCU or DFCB.
Dual-Duplexer Unit
 The DDPU performs the following
functions:

› Provides lightning protection through the
ANT port
› Detect VSWR alarms in the antenna system
› Control the gains for the receive low noise
amplifier
› Transmits multiple routes of RF signals from
the transmitter to the antenna
Combining Unit
 The DCOM combines two routes of TX
signals from the DTRU, and then sends
them to the DDPU


The power distribution unit consists of the
› DC lightning arrester,
› EMI filter,
› PGND bar,
› Busbar terminal socket (top)
› Busbar (right)

The signal lightning protection subrack is
installed on top of the cabinet. It is
configured with the following boards:
› DMLC
› DELC
› DSAC
Monitor Signal Lightning-Protection Card
 The DMLC performs the following
functions:

› Provides lightning protection for Boolean
input and output signals
› Provides lightning protection for analog
signals that are transmitted from the smoke
sensor, water sensor, door control sensor,
infrared sensor, humidity and temperature
sensor
E1 Signal Lightning-Protection Card
 The DELC performs the following
functions:

› Provides lighting protection for E1 signals

Signal Access Card

The DSAC performs the following
functions:
› Provides six Boolean alarm inputs
› Provides lightning protection for BITS clock
signals