Wireless Innovations Group
2601 Telecom Parkway
Richardson, Texas 75082
400/800 MHz Fiber Optic & RF Fed Bi-Directional
Amplifier Operations / Maintenance Manual
DWG NO:
AE04B-A1669
Rev: B
Date
: 06/18/2008
Page
:
59
of 63
3
If the measured output signal level exceeds +30 dBm, reduce the fiber optic gain (i.e.
adjust BDA’s fiber optic transceiver front panel potentiometer) so that the output power
level is equal to +30 dBm.
NOTE:
No additional fiber gain adjustment will be required after the fiber optic gain has
been set. If any additional gain adjustments are required they must be performed via the
RS232 port.
The RF fed BDA gain setting is performed at the factory and no field adjustments are
required. With a 48 dB factory gain setting, the maximum input signal level is –18 dBm.
This input level will ensure that FCC power limit (+30 dBm) is not exceeded.
UPLINK GAIN SETUP
The fiber fed BDA provides 18 dB of gain for 9 dB of optical loss. The factory gain
setting for the fiber fed BDA is 48 dB. Due to the various fiber optic link losses found in
a communication system, the uplink fiber optic gain must be adjusted so not to overdrive
the fiber optic link when high power transmitters are operating near the BDA. The
equipment needed and the gain test setup required for this adjustment is shown in Figure
6.2 below.
Figure 6.2 Uplink Gain Test Configuration
1
Using the signal generator, inject a – 43 dBm signal into the uplink operating passband of
the fiber fed BDA.
2
Measure the output signal level of the fiber optic transceiver chassis (i.e. located near the
base receiver station) using the spectrum analyzer.
3
If the measured output signal level exceeds – 4 dBm, reduce the fiber optic gain (i.e.
adjust fiber optic transceiver front panel potentiometer) so that the output power level is
equal to - 4 dBm.
Spectrum
Analyzer
Fiber Optic
Transceiver
Chassis
Fiber Fed
BDA
Signal
Generator
Fiber Cable
RF Cable
RF Cable
- 4 dBm
-43 dBm
