COBHAM SAILOR 900 - Fixed TX Gain Principle; Figure 6-13: Fixed TX Gain Principle

Calibration
98-150471-A02 Chapter 6: Configuration 6-17
Configuration
6.2.8 Fixed TX gain principle
The SAILOR 900 VSAT High Power uses a new transmitter chain concept. After calibration it
provides a fixed gain of 48 dB from the Tx-port of the ACU to the output of the BUC. The
advantages of the fixed TX gain principle are:
• Fixed TX gain over frequency and cable length
• TX gain independent of antenna cable length
• Utilization of the full 20 W BUC power over frequency
• P1dB compression point the same over frequency
When installing the SAILOR 900 VSAT High Power you make a cable calibration. At that
point every installation finds the same P1dB compression setting regardless of cable length.
The P1dB compression point is approximately -5 dBm at the ACU Tx-port. Additionally the
SAILOR 900 VSAT High Power system monitors the TX gain in real time.
* You find the maximum cable loss at Maximum allowed RF loss in the ADU cable on
page 3-20.
Example: ACU Tx-port power: -5 dBm > BUC output = +43 dBm (compression)
Figure 6-13: Fixed TX gain principle
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SAILOR900HP.book Page 17 Monday, July 18, 2016 12:44 PM