MINI-LINKEandEMicro
3.3.2.9 Receiver Block
The received signal is fed from the input branching filter into a low noise
amplifier and down-converted to 140 MHz.
Receiver Oscillator and Filter
An LO signal for the down-conversion is generated in the same way as for the
transm itted signal. A frequency error signal from the MMU is used to shift the
receiver VCO in order to facilitate an AFC -loop.
3.3.2.10 Receive IF Signal Processing
The 140 MHz receiving IF signal from the receiver is amplified and fed to the
cable interface. A dditionally, a portion of the signal is fed to a calibrated detector
to provide an accurate receiver input level measurement. The measured level is
accessible either as an analog voltage at the alignment port or in dBm through
the operation and maintenance system.
3.3.3 Filter Unit
Branching Filter
On the transmitting side, the signal is fed to the antenna through an output
branching filter. The signal from the antenna is fed to the receiving side through
an input branching filter. The antenna and both branching filters are connected
with an impedance T-junction.
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AE/LZT 110 2012 R8C 2002- 03-04
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