Safran CORTEX CRT Quantum, Руководство пользователя

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COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
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It cannot be duplicated or distributed without expressed written consent.
Page 58
When the two IF signal levels differ by more than 10 dB, the DCU automatically switches from Combining to Best
Channel mode. In this case, the DCU switches back to Combining mode only when this difference decreases to
less than 9.5 dB.
The relative amplitude of a channel (A or B) is given by:
Amplitute_Channel
Amplitute_Cha Amplitute_Channel_B
× 100
In the case of combining on direct PCM IF Receivers, the Eb/N0 status are used to compute the combining
coefficients (instead of the IF levels in the case of video IF Receivers).
The sum of the relative signal amplitudes is 100. The best case (3-dB gain) is when the two signals have the
same SNR.
3.3.5.4.
Signal Routing
The effective signal routing may differ from the programmed routing in the following conditions:

When the diversity combining is disabled, or

When the combining status is set to Alarm (alarm conditions are described above), or

During IF signal acquisition. Note that when both IF Receivers are unlocked, Channel
A is routed to output 1 and Channel B to output 2.