Mini-BDA OVERVIEW:
The Mini-BDA assembly extends the coverage area of radio communications in
buildings and RF shielded environments. The Mini-BDA has dual RF paths to extend
coverage in two distinct frequency bands.
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.
Mini-BDA BLOCK DIAGRAM DESCRIPTION:
Refer to Figure 1 for the following discussion.
The Mini-BDA Downlink path receives RF signals from the base station and amplifies
and transmits them to the subscriber. The Mini-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 PCS A
frequency bands are as follows:
1850-1865 MHz for the Uplink and 1930-1945 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.
Mini-BDA Options:
The Mini-BDA can be used as a line amplifier. With an optional external bias-tee, the
Mini-BDA will function with power coming from the In-building antenna.
Optional External Bias-Tees
(For .1/.1 Watt Models only)
An optional 9 pin D-sub connector is available for external alarm monitoring (See
Figures 3 & 3a).
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