Ericsson RBS 2106 Reference Manual page 91

per sector. A combination of three CDU-Fs can handle 12 transceivers
on two antennas.
CDU-G can be configured either for high capacity or for high coverage.
It is a combiner that can be used for synthesizer hopping.
To achieve capacity, CDU-G is used in a configuration where the
hybrid combiner in the dTRU is used. Up to two dTRUs (four
transceivers) can be connected to two antennas. One-, two- and
three-sector configurations are supported.
To achieve maximum coverage, CDU-G is used in a configuration
where the hybrid combiner within the dTRU is not used. Only one
dTRU can be connected to each antenna. The number of dTRUs in an
RBS 2106 cabinet is limited to three in this case.
Double Transceiver Unit (dTRU)
RBS 2106 has capacity for a maximum of six dTRUs. The dTRU
contains two TRXs for transmission and reception of two radio carriers.
It has a built-in combiner with the optional possibility of combining 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.
Configuration Switch Unit (CXU)
The task of the 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 minimize the amount of cable types for connecting
the CXU with the dTRUs and the CDUs.
The CXU is configured by means of software.
Alternating Current Connection Unit (ACCU)
The ACCU connect, disconnects, and distributes the incoming AC
power supply to the PSUs and the climate unit. It consists of two parts:
a Connection Unit and a Distribution Unit.
The Connection Unit (ACCU-CU) houses the mains switch, overvoltage
protection and the EMC-filter. The AC mains supply is connected to
the cabinet at the ACCU-CU.
The Distribution Unit (ACCU-DU) consists of circuit breakers for the
AC mains supply. It includes the AC mains control for cold start-up,
and distributes the main power to the PSUs and the climate unit. It also
provides an AC service outlet for equipment needed during installation
and maintenance. It is located above the TM/battery spaces.
Power Supply Unit (PSU)
The RBS 2106 contains up to four Power Supply Units for connection
to AC mains. The PSU converts 120 - 250 V to regulated +24 V DC.
EN/LZT 720 0008 P2A
2001-11-28
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Product Data RBS 2106
89 (485)