DECODING METHOD AND DECODING APPARATUS IN TRELLIS OR TURBO TRELLIS CODING MODULATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a decoding method and a decoding apparatus capable of considerably reducing the computation complexity in the trellis or turbo trellis coding modulation system.;SOLUTION: The trellis decoding apparatus is configured such that a square Euclid distance calculation means 11 of a decoder 1 specifies a representative metric of an object signal point from a received signal by referencing to a lookup table to calculate a square Euclid distance, a branch metric calculation means 12 calculates a branch metric formed by inverting the sign of the square Euclid distance, a forward path metric calculation means 13 calculates a path metric in time series, a hard decision block 2 applies hard decision to the path metric to obtain three lower-order bits, and a higher-order bit decoder 3 decodes the higher-order bits on the basis of the three lower-order bits and the received signal.;COPYRIGHT: (C)2006,JPO&NCIPI