Coding gain in multirate paraunitary filter banks

Discusses the problem of optimizing the coding gain of paraunitary subband coding systems. Given the statistics of the input, they have developed an algorithm for finding a paraunitary subband coding scheme which maximizes the coding gain. This is therefore an extension of the Karhunen-Loeve transform to systems of higher orders. The study therefore gives a valuable bound on the coding gains of paraunitary subband coders. It also gives a yard-stick for evaluating the performance of suboptimal subband coding schemes used in practice