User Manual

Combining and Distribution Unit
Hybrid Combiner
The hybrid combiner combines two TX signals to a
common output. It is a broadband combiner, but there
is a 3 dB combing loss in the TX path.
Duplexer The duplexer allows simultaneous transmission and
reception on the same antenna. It lets the TX signals
pass to the antenna and lets the RX signals from the
antenna to the RX part.
MCU The MCU measures forward and reflected signal levels
at the CDU output. The signals are forwarded to the
TRU via cables on the front of the CDU.
4.2 RX Part
There are two RX chains in CDU-C+. The RX part consists of the follo
wing:
• A duplex filter (duplexer), first path only
• A bias injector
• An RX Band-Pass filter (RXBP)
• An RX Distribution Amplifier (RXDA)
• Splitters
Duplexer
See Page 5.
Bias Injector The bias injector provides power to and supervises an
optional TMA.
RXBP
The RXBP lets RX signals between two speci fied
frequencies pass and removes unwanted out-of-band
signals.
RXDA
RXDA amplifies the RX signal.
Splitter
The splitter divides the RX signals for transmission to
the TRUs. It has no filtering or gain.
5
EN/LZT 720 0278 Uen R1B 2010-08-09