G-Way Microwave / G-Wave CELLABHW70 Manual De Usuario

Descargar
Página de 13
 
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 SMR frequency 
bands are as follows: 806-821 MHz for the Uplink and 851-866 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: 
 
An optional 9 pin D-sub connector is available for external alarm monitoring (See 
Figures 3 & 3a).  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Page 3