Hybrid decoding means to combine different iterative decoding algorithms with the aim of improving error performance or decoding complexity. In this work, we introduce "time-invariant" hybrid (HTI) algorithms, and using density evolution show that for regular low-density parity-check (LDPC) codes and binary message-passing algorithms, HTI algorithms perform remarkably better than their constituent algorithms. We also show that compared to "switch-type" hybrid (HST) algorithms, such as Gallager's algorithm B, where a comparable improvement is obtained by switching between different iterative decoding algorithms, HTI algorithms are far less sensitive to channel conditions and thus can be practically more attractive.

Density evolution, Hybrid decoding, Iterative coding schemes, Low-density parity-check (LDPC) codes, Message-passing decoding algorithms
dx.doi.org/10.1109/LCOMM.2004.827438
IEEE Communications Letters
Department of Systems and Computer Engineering

Zarrinkhat, P. (Pirouz), & Banihashemi, A. (2004). Hybrid hard-decision iterative decoding of regular low-density parity-check codes. IEEE Communications Letters, 8(4), 250–252. doi:10.1109/LCOMM.2004.827438