User's Manual

BDA OVERVIEW:
The BDA assembly enhances the coverage area of radio communications in
buildings and RF shielded environments. The unit features low noise figure and wide
dynamic range. It is based on a duplexed path configuration with sharp out of band
attenuation allowing improved isolation between the receiving and transmitting paths.
BDA BLOCK DIAGRAM DESCRIPTION
:
Refer to figure 1 for the following discussion.
The BDA Downlink path receives RF signals from the base station and amplifies and
transmits them to the subscriber. The BDA Uplink path receives RF signals from the
subscriber and amplifies and transmits them to the base station. The Uplink and
Downlink occupy two distinct frequency bands. For example, the PS7 frequency
bands are as follows: 793-805 MHz for the Uplink and 763-775 MHz for the Downlink.
Two diplexers isolate the paths and route each signal to the proper amplifying
channel.
An Automatic Level Control (ALC) allows for output power limiting. A variable step
attenuator gives 0 – 30 dB of attenuation in 2 dB steps. The use of these controls is
covered in the “OPERATION” section, later in this document.
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