Framing And Cycle Length; Encoding; Scrambling; Figure 55: Frame Aligned With File - Safran CORTEX Series User Manual

3.6.1.2.2

Framing and Cycle Length

When data are generated from a file, if the Cycle Length is compatible with the frame length i.e. if the
actual number of user data needed for each frame (thus excluding the Synchronization Word, the
Parity bits and the FECF) is equal to the Cycle Length, the first bit of the file is the first user bit of the
frame.
ASM
3.6.1.2.3

Encoding

Data encoding is possible at the internal framing level. The following encoders are supported
(according to CCSDS 131.0-B-2):

RS (223,255), and RS (239,255)

LDPC (8160,7136) or "NASA-shortened". This code is known as LDPC 7/8 in the GUI.

LDPC 1/2, 2/3, 4/5 with frame sizes of 1024, 4096 and 16384 bytes

DVB and DVB DSNG
The test unit supports all the features of the demodulator. Please refer to section 3.4
detailed presentation of the supported features.
Due to their "modulation scheme" nature, DVB-S2 and SCCC are described in the Modulation chapter.
3.6.1.2.4

Scrambling

In addition to the CCSDS Scrambling, the Scrambling can be entirely customized in terms of:

Initialization

Generator polynomial

Offset (in bits)
When the offset is set to a non-zero value n, it means that the scrambling process is reinitialized n bits
after the beginning of the frame.
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HDR-4G+ USER'S MANUAL
Frame Length
User Data
Cycle Length
Beginning of the File

Figure 55: Frame aligned with File

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Ref. DTU 100782
Is.Rev 3.5
Date: June 1, 2021
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