Reference Manual

Table Of Contents
Product Data
Dual Duplex TMA (ddTMA)
Antenna
TX/RX
P007931A
RBS
ddTMA
Figure 40 Dual Duplex TMA (ddTMA)
The ddTMA is to be used for GSM 900, for all macro base stations and
1800 or 1900 systems for RBS 2206 and RBS 2106.
A Dual Duplex TMA contains two duplex lters and a low noise
amplier. The rst duplex lter splits up the signal path from the
antenna into one transmitter and one receiver path. The received signal
is amplied in the low noise amplier. After amplication, the receiver
and transmitter paths are combined in the second duplex lter.
The ddTMA is a narrow-band product and is available in a number of
versions depending on the frequency band to be used.
A bias-injector is used to feed the ddTMA with 15 V DC.
The unit has two 7/16 socket connectors, see gure below.
100 (421)
EN/LZT 720 0008 R1A
2001-06-26
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