Bit-Level Soft-Decision Decoding of Triple-Parity Reed-Solomon Codes through Automorphism Groups

This paper discusses bit-level soft decoding of triple-parity Reed-Solomon (RS) codes through automorphism permutation. A new method for identifying the automorphism groups of RS binary images is first developed. The new algorithm runs effectively, and can handle more RS codes and capture more automorphism groups than the existing ones. Utilizing the automorphism results, a new bit-level soft-decision decoding algorithm is subsequently developed for general (n,n-3,4) RS codes. Simulation on (31,28,4) RS codes demonstrates an impressive gain of more than 1 dB at the bit error rate of 10^-5 over the existing algorithms.