Improved Approximately Lower Triangular Encoding of LDPC Codes

Concerning the high encoding complexity of low-density parity-check (LDPC) codes, an improved approximately lower triangular (ALT) encoding method is proposed, which is able to take full advantage of the characteristics of the sparse parity-check matrix, such as cyclicity and equality of row weight. Experimental results show that, the proposed method can reduce dramatically the memory requirements in hardware implementation, while maintaining the computational complexity nearly.