A puncturing algorithm for rate-compatible LDPC convolutional codes

A family of rate-compatible (RC) punctured low-density parity-check convolutional codes (LDPC-CCs) is derived from an LDPC-CC by periodically puncturing encoded bits (variable nodes) with respect to several criteria: (1) ensuring the recoverability of punctured variable nodes, (2) minimizing the number of completely punctured cycle trapping sets (CPCTSs), and (3) minimizing the number of punctured variable nodes involved in short cycles. As an example, a family of RC punctured LDPC-CCs with rates 4/9, 4/8, 4/7, 4/6, and 4/5 are obtained from the (21,3, 5) Tanner LDPC-CC.