Signal Processing - Safran CORTEX CRT Quantum User Manual

3.3.5.3. Signal Processing

The combining function can be in 4 different status:
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In alarm conditions, diversity combining is inhibited: Channel A is routed to output 1 while Channel B is routed to
output 2. The two receivers are totally independent.
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COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
Disable if the diversity combining is disabled.
Alarm if the diversity combining is enabled and if the equipment is not correctly configured.
It is the case when:
In Video mode:
The demodulation mode is not the same for Channel A and Channel B, or
The carrier acquisition ranges of the two IF Receivers do not overlap, or
The pre detection filters differ in case of pre detection diversity combining, or
The pre detection loop bandwidth is larger than the IFR loop bandwidth divided by 10.
In PCM mode:
The demodulation mode is not the same for Channel A and Channel B, or
The carrier acquisition ranges of the two IF Receivers do not overlap, or
The pre detection filters differ in case of pre detection diversity combining, or
The pre detection loop bandwidth is larger than the IFR loop bandwidth divided by 10.
Unlocked if the PLL between the two channels fails to lock in Pre Detection Diversity
combining. In this case, diversity combining is inhibited: Channel A is routed to output 1
while Channel B is routed to output 2.
OK: The equipment is correctly configured and the diversity combining is enabled. The
combining gain (versus best channel selection) is:
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3
2.5
2
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Best channel level - Worst channel level
in dB
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It cannot be duplicated or distributed without expressed written consent.
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Safran Data Systems
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Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
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