Safran CORTEX Series - Customized Data De-Randomization

HIGH DATA RATE RECEIVER
HDR-4G+ USER’S MANUAL
Ref. DTU 100782
Is.Rev 3.5
Date: June 1, 2021
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Page 127
Customized Data De-randomization 3.4.4
The Cortex HDR provides a fully programmable de-randomization function.
Are programmable:
- the polynomial of the generator of the pseudo-random sequence The supported maximum
degree of the polynomial is 16 (refer to the examples below)
- the initial value of the generator (fully programmable between 0x0000 and 0xFFFF).
Example 1: Polynomial: X
15
+ X +1 (polynomial set-up value: 0x8003)
Example 2: Polynomial: X
8
+ X
7
+ X
5
+ X
3
+1 (polynomial set-up value: 0x1A9)
For modulation schemes with separate I and Q, each de-randomization function is configurable
independently of each other.
The customized de-randomization can performed before or after the associated decoding (Reed
Solomon or LDPC). That is programmable (refer to CADU window).