Patent ID: 6154507
Filing Date: 2000-11-28
Classification: H04L

Abstract:
A method for demodulating a symbol sequence comprising the steps of:receiving a portion of a transmission signal, forming a received signal, said received signal having a received signal level associated therewith and including a plurality of symbols, said plurality of symbols forming a symbol stream;sampling said received signal at symbol period intervals, forming a received symbol stream, said received symbol stream having a present state and a plurality of previous states associated therewith;calculating, from a plurality of metrics formed from at least one previous state of said received symbol stream, a multiplicity of partial candidate metrics;eliminating, from each of said multiplicity of partial candidate metrics, at least one common term therein;calculating respective current state metrics from each of said multiplicity of partial candidate metrics without a common operator;selecting a given one of said partial candidate metrics without said common operator, said selected given one of said partial candidate metrics without said common operator being a winning partial candidate metric;recalculating said given partial candidate metric with said common operator; andforming a new full path metric, wherein said full path metric includes said winning partial candidate metric.