Girth-Eight Reed-Solomon Based QC-LDPC Codes

This paper presents a class of regular quasi-cyclic (QC) LDPC codes whose Tanner graphs have girth at least eight. These codes are constructed based on the conventional parity-check matrices of Reed-Solomon (RS) codes with minimum distance 5. Masking their parity-check matrices significantly reduces the numbers of short cycles in their Tanner graphs and results in codes which perform well over the AWGN channel in both waterfall and low error-rate regions.