Reference Manual

RBS 2106 Radio Base Station
EN/LZT 720 0222 R3A 17 (30)
DC/DC Converter
The DC/DC converter can supply -48 V DC power to transmission equipment
in the TM compartment. It converts +24 V DC to -48 V DC.
Number of units: 0 – 2
ddTMA
The ddTMA is to be mast-mounted and placed close to the antenna. It
improves the receiver sensitivity. The ddTMA saves feeder cables by
duplexing RX and TX signals to the same cable.
Number of units per cabinet: 0 – 6.
DXX – Digital Cross Connector
Digital Cross Connect (DXX) is a plug-in unit which combines cross-connect,
control and interface functions. It has four 2 Mbit/s interfaces complying with
the G.703 standard. If the DXX option is used, it is located in an Optional
Expansion Unit (OXU) position in the DXU/ PSU subrack.
Number of units: 0 – 1
OXU – Optional Expansion Unit
The following Optional Expansion Unit (OXU) positions are available:
• Four spaces in the DXU/PSU subrack
• One 19-inch OXU position is available between the CXU and the dTRU
subrack.
RUs which typically are located in the OXU slots include the DXX and the
TMA-CM. The 19-inch position above the CXU is used for an Antenna Sharing
Unit (ASU) in co-sited cabinets.
TM – Transport Module
The Transport Module (TM) is a space in the cabinet reserved for transmission
equipment.
TMA-CM –Tower Mounted Amplifier Control Module
The TMA-CM is used to provide ddTMA with 15 V DC power through the bias
injectors. It also identifies ddTMA faults and forwards this information to the
alarm module in the RBS. If a TMA-CM is used, it is located in one of the four
OXU positions in the DXU/PSU subrack.