An efficient pseudo-codeword search algorithm for Belief Propagation decoding of LDPC codes

We introduce the use of fast flat histogram (FFH) method employing Wang Landau algorithm in an adaptive noise sampling framework using random walk to find out the pseudo-codewords and consequently the pseudo-weights for the belief propagation (BP) decoding of LDPC codes over an additive white Gaussian noise (AWGN) channel. The FFH method enables us to tease out pseudo-codewords at very high signal-to-noise ratios (SNRs) exploring the error floor region of a wide range of codes varying in length and structure. We present the pseudo-weight (effective distance) spectra for these codes and analyze their respective behavior.