All-pass analysis-synthesis frequency interpolation filterbanks

The authors present a solution to the problem of designing a class of analysis-synthesis digital filterbanks that exhibit the following properties: Given N center frequencies f_i, the frequency response of the ith filter is unity at f _i and zero at the other frequencies, and the sum of the squares of the frequency responses is an allpass network. The design of typical filterbanks with linearly and logarithmically spaced frequencies is presented, and the frequency response is exhibited. These filterbanks are computationally efficient