Enhancing the error-correcting performance of LDPC codes for LTE and WiFi

Low-density parity-check (LDPC) codes are one of the most powerful error-correcting codes for wireless communication of high-speed data. This power comes from an efficient decoding scheme, the sum-product algorithm (SPA), which runs over the bipartite graph defining the code. In this work, we propose to use a modified version of the decoding algorithm over the LDPC codes used in Long Term Evolution (LTE) and WiFi and demonstrate that with the same number of iterations, without any increase in time complexity, we can achieve an enhanced error-correcting performance. The only trade off of the system is the necessary storage of the decoding sets, for a total size of n_s × n, where n_s is the number of decoding sets used and n is the codeword length. In this work, the maximum value of n_s used is 5, which makes the trade-off fairly acceptable, considering that the coding gain is obtained virtually free-of-charge.