PEG algorithm based interleavers design for systematic IRA codes

Irregular-repeat-accumulate (IRA) codes are random-like codes having extremely good performance over AWGN channel. They can be viewed as special kinds of LDPC codes in the way their parity-check matrix are sparse. Like LDPC codes, they can be decoded using the messages-passing algorithm efficiently, while the existence of short length circles in their corresponding factor graph representation has a deleterious effect on the BER performance of the codes. Progressive edge-growth (PEG) algorithm is a famous method to construct factor graph without short circles. In this paper, we use PEG algorithm to construct the parity-check matrix of IRA codes firstly, and then deduce the interleaver design of the codes. Experimental results show significant improvement on the BER performance of the IRA codes with designed interleaver over the IRA codes with randomly choose interleaver.