A new reduced-complexity decoding algorithm for low-density parity-check codes that operates entirely in the log-likelihood domain is presented. The computationally expensive check-node updates of the sum-product algorithm are simplified by using a difference-metric approach on a two-state trellis and by employing the dual-max approximation. The dual-max approximation is further improved by using a correction factor that allows the performance to approach that of full sum-product decoding.
By: Evangelos Eleftheriou, Thomas Mittelholzer and Ajay Dholakia
Published in: Electronics Letters, volume 37, (no 2), pages 102-4 in 2001
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