Dvb-S2 & Sccc; If Signal Generation; If1 And If2 - Safran CORTEX Series User Manual

3.6.2.5 DVB-S2 & SCCC
The test modulator supports advanced modulation schemes such as SCCC and DVB-S2. These
modes are entirely compliant to:

The CCSDS specification 131.2-B-1 (SCCC)

The CCSDS specification 131.20-O (SCCC-X)

The functioning of the Demodulator Unit
These two modes support a VCM functioning.
VCM can be based on:

Frame: The configuration (ACM, modulation, coding rate, pilots ...) is changed after a
determined number of frames

Time: The configuration is changed after a certain amount of times. Even in this mode, it is
guaranteed that the configuration is not changed in the middle of a frame.
The sequences of the different configurations are described inside ASCII Files available in:
Each file contains 1 line per ACM.
It begins with #frame# when the VCM is frame-based. If not, it is time-based.
Each line must have the following syntax:
Nb Frames ; modulation OFF ; stop ; ACM nb ; pilot ; short frame (Frame-based
mode)
time (seconds); noise level (dBm/Hz) ; ACM nb ; pilot ; short frame (Time-
based mode)
Lines beginning with '#' character and blank are ignored.
See 4.5.8.2.2.3 for more details.
Note: Even in a CCM, a change of configuration (ACM) does not generate any errors due to the
reconfiguration.
3.6.3

IF Signal Generation

3.6.3.1

IF1 and IF2

For each Modulation Unit, the following characteristics of the simulated telemetry signal can be
configured:

Carrier: Adjustable Level and ON/OFF switch

Noise: Adjustable Level and ON/OFF Switch
Note:
The "raw" signal-to-noise ratio (SNR or E
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This document is the property of
3.5
June 1, 2021
.
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