Safran CORTEX RTR NeXt Series, Руководство пользователя

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Radio Telemetry Receiver
User's Manual
Ref. D104004
Is.Rev 07
Previous Ref.: DTU000567
Date: 21/06/2021
© Safran Data Systems
– IMP000074 e14r1
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Safran Data Systems
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Page 73
6.9 Quality factor.
The telemetry quality factor as the eye diagram viewer is a very helpful tool to evaluate the reception
quality.
The user has mainly to focus on the color:

Green

reception OK

Yellow

reception OK

Orange

the reception is on the edge, the bit sync may generate many errors and may lose
synchronization

Red

the reception is lost or will be lost.
The telemetry quality factor is computed taking as reference the data stream without any filtering.
The schema here above illustrates this computation.
All the hatched zones are linked to the transmit pre-modulation filter, to the RX IF filter and also to the
Rx Video filter and are considered has a loss compare to the square data stream. It is why even a
transmission with a very good budget link will not have a quality factor above 15 dB.
When the filters are rather tight, the quality factor may be orange. In this case, it is important to look at
the eye diagram to check its aperture.