ITERATIVE DECODING OF SIGNALS RECEIVED OVER A NOISY CHANNEL USING FORWARD AND BACKWARD RECURSIONS WITH WARM-UP INITIALIZATION

摘要

A method, apparatus and program. The method comprises: receiving a signal comprising a sequence of encoded symbols, each corresponding to one of a plurality of possible states; for each symbol in the sequence, determining a set of state metrics each representing a probability that the respective symbol corresponds to each of the plurality of states; and decoding the signal by processing runs of recursions, using runs of forward recursions and runs of reverse recursions. The decoding comprises performing a plurality of repeated iterations over the sequence, and for each iteration: dividing the sequence into a plurality of smaller windows, processing the windows using separate runs of recursions, and performing an associated warm-up run of recursions for each window. The decoding further comprises, for each repeated recursion: alternating the direction of the warm-up runs between forward and reverse with each successive iteration over the sequence, storing one of the sets of state metrics from each window, and initialising the warm-up run of each window using a corresponding stored set of state metrics from a previous iteration.