The performance of multithreshold decoder over fading channels

Abstract

Multithreshold decoders (MTD) for self-orthogonal codes (SOC) are discussed. It's known MTD can provide near optimum decoding with linear complexity only. Bit-error rate performance of MTD in multipath Rayleigh and Rician fading channels is analyzed. Several questions of application of MTD with orthogonal frequency division multiplexing and multipleinput and multiple output technology for improving reliability of communication with unmanned vehicles are discussed. The performance of multithreshold decoders in such conditions is presented. Comparison with decoders for DVB-S2 low-density parity-check codes is presented. It's shown MTD provides comparable with LDPC decoders performance at much lower complexity.

Soft decision decoding techniques in multithreshold decoding of self-orthogonal codes

“…It is shown that change of a method of computation of weight factors of checks allows to improve significantly characteristics of used codes in case of their decoding by the MPD methods in case of big noise level in case of use of soft modems. It has been shown that in this case the MTD can provide in a Gaussian channel characteristics, on 1, 2-7-1,4 dB better than the "hard" modem [4]. …”

“…The algorithms executing only very simple, uniform and fast operations will appear the cheapest in case of all options of implementation. Earlier, theoretical and application results about multi threshold decoding (MTD) algorithms for binary digital streams in Gaussian channels with a large noise level was considered in [4][5][6]. MTD is a very simple iterative algorithm for error correction.…”

“…As in case with traditional threshold decoding [7] in MTD at each iteration weighted checks are summed; if the sum is greater than the threshold the checks are changed together with the decoded symbol. The number of decoding iterations I is not exceed 50, and the general decoding complexity of MTD is evidently estimated for the minimum code distance d < 25 as N -(d+2)(l+4) [4].…”