An effective puncturing scheme for rate-compatible LDPC codes

We consider the problem of finding good puncturing patterns for rate-compatible LDPC codes over additive white Gaussian noise (AWGN) channels. When studying the recovered process of punctured nodes, Ha et al maximized the number of lower Ä-SR nodes and obtained a so-called grouping and sorting puncturing scheme, where only single survived check node was guaranteed. In this paper, we investigate the effect of multiple survived check nodes and afford theoretical analysis to them. Based on the analysis, we propose an effective puncturing scheme called MSCN, which maximizes the number of survived check nodes. The MSCN scheme is quite different from the grouping and sorting scheme in the rules of finding nodes and update. By simulations, the MSCN scheme is shown to be superior to the grouping and sorting scheme over AWGN channels at low rates for rate-compatible LDPC codes.