Abstract
In this thesis, an iterative soft-decision decoding algorithm is proposed for Reed-Solomon (RS) codes. The concept of adapting the parity-check matrix in is combined with informed dynamic scheduling in this proposed decod- ing algorithm. Prior to each decoding iteration, the parity-check matrix is re-arranged according to the log-likelihood-ratio (LLR) of the codeword bits on the last decoding iteration, on purpose to lower the influence of the least reliable variable nodes (LRVNs) on the decoding process. With the help of informed dynamic scheduling, the important decoding messages can be scheduled to be updated first, and the reliability of the LRVNs can be en- hanced. The simulation results show that the proposed decoding algorithm can provide significant improvement in the error-rate performance. By us- ing the proposed algorithm, a gain of 0.5 dB can be achieved compared to the conventional adapting belief propagation algorithm. Another reliability- based decoding algorithm, ordered statistic decoding (OSD) algorithm, can be added to improve performance further.