Normalized Switch SchemesforLowDensity Parity CheckCodes

Chen Gong

Published Jan 1, 2006• 0 citations

Abstract

Thispaperaddresses switch schemes forswitch typehybridharddecision iterative algorithms decoding finite length lowdensity parity check(LDPC)codes. After piecewise analysis forextrinsic transfer information (EXIT) chartfamily andexploration offixed points, onegeneral switch schemenamednormalized switch scheme, forwhich majority based(MB)algorithms andGallager's decoding algorithm B (GB)areextremecases, isproposed. Several specific normalized switchscheme,named expanded optimal switch schemeandtail-cut (TC)optimal switch scheme, aregivenandtheir convergence properties are analyzed. Simulation showsthatcompared withGB that holdsoptimality forinfinity length codes, proposed switch schemesshowperformance improvements whileenjoying lesssensitivity tochannel parameter underestimations for finite length codes.

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