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VI.
THEORY OF OPERATION
The PBBA is a broadband bi-directional amplifier. It has two channels, one is the
Forward In-Band and the other is Forward Out-of-Band/Reverse. The Forward In-Band
channel has a high gain amplifier chain and a band pass filter. This channel boosts the
signals that come through the filter. These are the inbound signals. Above and below
the filter passband are the outbound signals which are within the 100 to 2000 MHz range
and are handled by the other channel. The Forward In-Band channel uses a broadband
attenuator/amplifier module which has a 15dB dynamic range and a gain of around
20dB at 0dB attenuation setting. The attenuation, therefore the overall module gain/loss,
is digitally set via computer interface.
The Forward Out-of-Band/Reverse channel covers the frequency range of 100 to 2000
MHz. Due to the configuration of this channel it has a fixed insertion loss. With the two
channels integrated, the unit provides bi-directional amplification of inbound signals.
