Patent ID: 6856657
Filing Date: 2005-02-15
Classification: H03M,H04L

Abstract:
1. A method of decoding a received convolutionally coded sequence of signals represented by a trellis of block length N, comprising the steps of: a) dividing the trellis into a plurality of sections; b) selecting a section of length L of the trellis, c) decoding a portion of the trellis using forward recursion from a point P d) decoding a portion of the trellis using backward recursion from a point P e) decoding the portion of the trellis within the section using a forward recursion starting from the known state at the beginning of the section defined in step c) and a backward recursion starting from the known state at the end of the section defined in step d); f) calculating a soft output at each stage of the section using the forward recursion state metrics defined in step f), the backward recursion state metrics defined in step f), and branch metrics at each state, and outputting the soft output for that stage; and g) performing the forward sand backward recursions of step e) and the soft output calculations of step f) with a sliding window decoding method within the section, wherein the sliding window decoding method is characterized by a window length A, wherein A is less than L.