Reference Manual Part 1

RBS 2106
CXU
The task of the Configuration Switch Unit (CXU) is to cross-connect the CDU
and the dTRU in the receiver path. The CXU makes it possible to expand or
reconfigure a cabinet without moving or replacing any RX cables.
The RX inputs/outputs on the dTRU and the CDU are placed in such positions
that they minimise the number cable types used to connect the CXU to the
dTRUs and the CDUs.
The CXU is software configured.
Number of units: 1 – 2
DXU 21
The Distribution Switch Unit (DXU-21) is the central control unit for the RBS. It
supports the interface to the Base Station Controller (BSC), and it collects and
transmits the alarms. The DXU-21 controls the power and climate equipment
for the RBS. It has a removable compact flashcard that enables replacement of
a faulty DXU-21 without the need for loading RBS software from the BSC.
The DXU-21 is provided with four connections for transmission interfaces. It
can handle both 2048 kbit/s (E1) and 1544 kbit/s (T1) transmission interfaces.
The DXU-21 has hardware support for EDGE on 12 TRXs.
Number of units: 1
dTRU
The double Transceiver Unit (dTRU) contains two TRXs used to transmit and
receive two radio carriers.
It has a built-in combiner with the option to combine two TX signals into one TX
output. It is also prepared for four-branch RX diversity for further improvements
in sensitivity.
One version of the dTRU supports only GMSK and the other version supports
both GMSK and EDGE.
Number of units: 1 – 6
FCU
The Fan Control Unit (FCU) controls the fans in the cooling system by regulating
fan speed. The FCU is controlled by the DXU.
Number of units: 1
17 (36)
EN/LZT 720 0222 Uen R6A