Non-uniform filter banks based on a multi-prototype cosine modulation

A method of designing non-uniform FIR filter banks is presented. It is based on the cosine modulation of more than one prototype, having different passbands. The method aims at the cancellation of the main component of aliasing: this imposes constraints on the prototypes, which become dependent of each other. The method is simple and requires numerical optimization only for the narrowest prototype, being the others derived in a straightforward way from this one. For this reason, the method seems particularly suitable when banks with a large number of coefficients must be designed