Linear encoding of LDPC codes using approximate lower triangulation with postprocessing

A new technique is proposed for efficient encoding of low density parity check (LDPC) codes using the concept of approximate lower triangulation (ALT). Parity check matrix is preprocessed and encoded in O(n) complexity. This encoding technique is applied in the IEEE 802.11n based H matrix where the complexity is compared with the Richardson algorithm. The proposed adaptive message length (AML) encoding scheme takes less than half number of computations compared to the Richardson scheme while keeping similar bit error rate (BER) performance.