Gaussian approximation for sum-product decoding of low-density parity-check codes
Sae-Young Chung, Rudiger L. Urbanke, Tom Richardson · 2002
We use a Gaussian approximation (GA) for analyzing the sum-product algorithm for low-density parity-check (LDPC) codes and memoryless binary-input continuous-output additive white Gaussian noise (AWGN) channels. This simplification allows us to calculate the threshold quickly and to understand the behavior of the decoder better. We have also designed high rate LDPC codes using the Gaussian approximation that have thresholds less than 0.05 dB from the Shannon limit.