Ericsson RBS 2106 Hardware Reference Manual page 103

RBS 2106 and RBS 2206
3 Definitions
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The TMA compensates for signal loss in the receiver antenna cables, reduces
system noise and improves uplink sensitivity. The TMA can consist of a duplex
filter. Duplex is the function that allows communication in two directions
(sending and receiving) on one channel.
The TMA used for 12 TRX products is Dual Duplex TMA (ddTMA).
Some configurations can use a TMA designed for reception only (rTMA).
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The antenna reference point is the point where the radio signal crosses the
RBS border, that is, the connector for the antenna feeder. See the figure below.
1RWH The TMA is inside the RBS border.
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The antenna system is constituted by all RF transmission and reception
antennas, directed to cover the same area or multi-casting configurations.
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An ASU is used for sharing RX antennas between RBSs.
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RBS
TRX
TRX
.
.
.
TRX
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Combining
system
X
+
X = Antenna reference point
filtering
Radio Configurations
Antenna
P007531A
5 (90)