Generalized Channel Coding and Decoding with Natural Redundancy in Sources and Protocols

This paper develops a generalized channel coding and decoding architecture to describe the natural redundancy of sources (NRS), protocols, and the artificial redundancy of channel codes uniformly. Based on the joint protocol-channel decoding (JPCD) scheme we proposed earlier, a joint source-protocol-channel decoding (JSPCD) scheme is proposed with NRS further into account. Tests on the uncompressed Wikipedia English text source and the 802.11n TCP/IP/MAC protocol stack demonstrate that the more redundancy used for decoding, the better the performance, and the smaller the gap from the corresponding Shannon capacity limit. The proposed JSPCD scheme significantly outperforms the concatenated decoding scheme of JPCD and NRS decoder with acceptable computational cost. We also present a qualitative explanation for the results that the higher the modulation order adopted, the greater the performance gain from the perspective of channel capacity.