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Stochastic Iterative Decoders

Chris Winstead·Anthony Rapley·Vincent C. Gaudet·Christian Schlegel
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Abstract

This paper presents a stochastic algorithm for iterative error control decoding. We show that the stochastic decoding algorithm is an approximation of the sum-product algorithm. When the code's factor graph is a tree, as with trellises, the algorithm approaches maximum a-posteriori decoding. We also demonstrate a stochastic approximations to the alternative update rule known as successive relaxation. Stochastic decoders have very simple digital implementations which have almost no RAM requirements. We present example stochastic decoders for a trellis-based Hamming code, and for a Block Turbo code constructed from Hamming codes.

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Chris Winstead, Anthony Rapley, Vincent C. Gaudet, Christian Schlegel. 2005-01-30. Stochastic Iterative Decoders. https://arxiv.org/abs/cs/0501090

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