Design of Pseudo-QMF Banks with Rational Sampling Factors Using Several Prototype Filters

In this correspondence, a method is presented for designing filter banks that allow the spectrum of a signal to be split into nonuniform width subbands. The filters of the banks are obtained by the cosine modulation of more than one prototype. The method uses the cancellation of the main aliasing component of the reconstructed signal. This imposes constraints on the prototypes that become dependent on each other. The procedure can be applied to banks with both integer and rational decimation factors. Numerical examples are presented to show the effectiveness of the design procedure.