G-Way Microwave / G-Wave CELLAB25W90 사용자 설명서

The BDA provides long term, care-free operation and requires no periodic maintenance. 
There are no user-serviceable components inside the BDA.  
 
This section covers possible problems that may be related to the installation or operating 
environment. 
 

Possible causes: Bad RF cables and RF connections to antennas, Damaged antennas. 
 

Possible causes: 
Amplifier oscillation caused by insufficient isolation. The isolation between two antennas is 
given by the equation: 
Isolation = 92.5 + 20 Log (F x D) – Gt – Gr 
Where: 
F = frequency (GHz) 
D = separation (Km) 
Gt = transmit antenna gain (in the direction of the receive antenna). 
Gr = receive antenna gain (in the direction of the transmit antenna). 
 
For example, at the CELLAB frequencies, the antenna isolation at 100 m separation is about 
71 dB for omni-directional antennas (0 dB gain). To increase isolation, the antennas should 
have higher directivity and must be pointed away from each other. 
 

Possible causes: One channel with very strong power dominates the RF output of the 
amplifier. 
 
 
 
 
 
 

 

38 Leuning Street 

South Hackensack, NJ 07606 

Tel. 201-343-3140   Fax 201-343-6390 

 
 
 
 

 
 

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