Decoder architecture for cyclically-coupled quasi-cyclic low-density parity-check codes

Abstract

This invention provides a cyclically-coupled (CC-) quasi-cyclic (QC-) low-density parity-check (LDPC) code and its decoder architecture. The essence of the invention is to introduce the convolutional nature to a plurality of individual block codes internally so as to form a resultant block code with a prolonged code length while slightly increasing the hardware complexity in decoder realization. The CC-QC-LDPC code is formed by cyclically coupling a plurality of sub-codes each being a QC-LDPC code such that overlapping of some variable nodes between two consecutive sub-codes results. The decoder comprises plural sub-decoders each configured to decode the channel messages for one sub-code. The sub-decoders are arranged in a ring shape such that an individual sub-decoder is configured to communicate edge messages with two neighboring sub-decoders adjacent to said individual sub-decoder in the decoding of the channel messages. The sub-decoders are configured to operate concurrently for simultaneously decoding individual sub-codes.