Simplified block sliding window implementation of a map decoder

Abstract

A block sliding window data decoder includes a forward recursion calculator and a plurality of backward recursion calculators including a first backward recursion calculator and a second backward recursion calculator that receives inputs from the first backward recursion calculator. The first backward recursion calculator operates every D cycles to perform a backward recursion over received input signals, while assuming that all future states are equally likely. The decoder further includes a symbol probability calculator that receives inputs from the forward recursion calculator and from the first backward recursion calculator. A memory of the decoder stores the input signals and is organized as N cells, wherein for each cycle one of the N cells is written while N−1 of the cells are read and their contents provided to the forward recursion calculator and to the first and second backward recursion calculators. Each calculation cell of the decoder includes a normalizer for normalizing the input signal and signals processed by the forward recursion calculator and the first and second backward recursion calculators. The normalizer is implemented using AND functions.

Dependencies are inferred from the claim text.