DISTANCE AND DISTORTION ESTIMATION METHOD AND APPARATUS IN CHANNEL OPTIMIZED VECTOR QUANTIZATION

摘要

A channel optimized vector quantization apparatus includes means (40) for weighting a sample vector x by a weighting matrix A and means (44) for weighting a set of code book vectors ĉr by a weighting matrix B. Means (30W) form a set of distance measures {dw(Ax,Bĉr)} representing the distance between the weighted sample vector Ax and each weighted code book vector Bĉr. Means (34W) form a set of distorsion measure { alpha i(x)} by multiplying each distance measure by a channel transition probability pr|i that an index r has been received at a decoder when an index i has been sent from an encoder and adding together these multiplied distance measures for each possible index r. Finally means (36W) determine an index imin corresponding to the smallest distortion measure alpha i(x) and represents the sample vector by this index imin.