Safran CORTEX CRT Quantum - Turbo-Code; Table 24: Turbo Code

COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
© Safran Data Systems
This document is the property of Safran Data Systems.
It cannot be duplicated or distributed without expressed written consent.
Page 124
ASM
Check Symbols
Uncoded transfer frame #1
ASM
Check Symbols
Uncoded transfer frame #2
ASM
Check Symbols
Uncoded transfer frame #N
TMU Frame Length
TMS Format Length = N * TMU Frame Length
Figure 62: TMS File structure for Reed-Solomon encoding
3.4.3.3.4. Turbo-Code
This processing provides the capabilities corresponding to the encoding recommended in § 5 of CCSDS 131.0-
B-3. The corresponding decoding is license dependent. The minimum code rate: 1/2, 1/3, 1/4 or 1/6 is resource
dependent.
The Turbo-encoding is available in the File, Pseudo and BERT File operating modes.
It is activated by programming the parameter Frame Encoding to Turbo-code. The frames are generated by
using the parameters Frame Length and Turbo Code Rate of the TMU associated owing to the parameter TM
Flow for BER/Encoding. In the particular case of Turbo decoding, the TMU Frame Length has to be configured
with the uncoded information block length, expressed in bits. The Sync. Marker is automatically deduced from
the TMU Turbo Code Rate.
information
block length
codeblock length
bits [bytes]
bits [bytes]
code rate
1/2
1/3
1/4
1/6
1784
[2231]
3576
[447]
5364
[670.5]
7152
[894]
10728
[1341]
3568
[2232]
7144
[893]
10716
[1339.5]
14288
[1786]
21432
[2679]
7136
[2234]
14280
[1785]
21420
[2677.5]
28560
[3570]
42840
[5355]
8920
[2235]
17848
[2231]
26772
[3346.5]
35696
[4462]
53544
[6693]
sync. marker length
64
96
128
192
Table 24: Turbo code : information block and codeblock lengths
In Pseudo mode, the Frame Length of the associated TMU must be configured with the information block length
expressed in bits. The length of (sync. Marker + Turbo codeblock) is given by the formula:
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