3.2.4.8.2. RS Decoder parameters¶
The RS decoder was described by Reed and Solomon in 1960 [Rs-ISR60].
3.2.4.8.2.1. --dec-type, -D
¶
- Type
text
- Allowed values
ALGEBRAIC
CHASE
ML
- Default
ALGEBRAIC
- Examples
--dec-type ALGEBRAIC
Select the decoder algorithm.
Description of the allowed values:
Value |
Description |
---|---|
|
Select the Berlekamp-Massey algorithm [Rs-Ber15, Rs-Mas69] followed by a Chien search [Rs-Chi64]. |
|
See the common --dec-type, -D parameter. |
|
See the common --dec-type, -D parameter. |
3.2.4.8.2.2. --dec-implem
¶
- Type
text
- Allowed values
STD
GENIUS
- Default
STD
- Examples
--dec-implem GENIUS
Select the implementation of the decoder algorithm.
Description of the allowed values:
Value |
Description |
---|---|
|
A standard implementation of the RS. |
|
A really fast implementation that compare the input to the original codeword and correct it only when the number of symbols errors is less or equal to the RS correction power. |
Note
In the STD
implementation, the Chien search finds roots of the
error location polynomial. If the number of found roots does not match the
number of found errors by the Berlekamp–Massey algorithm, then the frame is
not modified.
When a frame is very corrupted and when the above algorithms can be
wrong in the correction by converging to another codeword, the GENIUS
implementation cannot fail. Results may then differ from a real word
implementation.
3.2.4.8.2.3. --dec-corr-pow, -T
¶
- Type
integer
- Default
5
- Examples
-T 18
Set the correction power of the RS decoder. This value corresponds to the number of symbols errors that the decoder is able to correct.
It is automatically calculated from the input and codeword sizes. See also the argument --enc-info-bits, -K .
3.2.4.8.2.4. References¶
- Rs-Ber15
E. R. Berlekamp. Algebraic Coding Theory (Revised Edition). World Scientific, May 2015. First edition from 1968. doi:10.1142/9407.
- Rs-Chi64
R. Chien. Cyclic decoding procedures for bose- chaudhuri-hocquenghem codes. IEEE Transactions on Information Theory (TIT), 10(4):357–363, October 1964. doi:10.1109/TIT.1964.1053699.
- Rs-ISR60
G. Solomon I. S. Reed. Polynomial codes over certain finite fields. Society for Industrial and Applied Mathematics, 8(2):300–304, June 1960. doi:10.1137/0108018.
- Rs-Mas69
J. Massey. Shift-register synthesis and bch decoding. IEEE Transactions on Information Theory (TIT), 15(1):122–127, January 1969. doi:10.1109/TIT.1969.1054260.