Math @ Duke

Publications [#319390] of Henry Pfister
Papers Published
 Fan, Z; Pfister, HD, Listmessage passing achieves capacity on the qary symmetric channel for large q,
Globecom Ieee Global Telecommunications Conference
(December, 2007),
pp. 283287, ISBN 1424410436 [doi]
(last updated on 2018/10/22)
Abstract: We discuss and analyze a listmessagepassing decoder with verification for lowdensity paritycheck (LDPC) codes on the qary symmetric channel (qSC). Rather than passing messages consisting of symbol probabilities, we pass lists of possible symbols and mark very likely symbols as verified. The density evolution (DE) equations for this decoder are derived and used to compute decoding thresholds. If the maximum listsize is unbounded, then we find that any capacityachieving LDPC code for the binary erasure channel can be used to achieve capacity on the qSC for large q. The decoding thresholds are also computed via DE for the case where each list is truncated to satisfy a maximum listsize constraint. The probability of false verification is considered for this case, and techniques are discussed to mitigate the problem. Optimization of the degree distribution is also used to improve the threshold for a fixed maximum list size. Finally, the proposed algorithm is compared with a variety of other algorithms using both density evolution thresholds and simulation results. © 2007 IEEE.


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