High speed IIR filters for QMF banks

Abstract

In this paper, we show that using allpass IIR subfilters and half-band FIR optimal filters from the minimal phase solution it is possible to design a filter which exhibits simultaneously very low passband attenuation, large stopband attenuation, narrow transition region and low arithmetic complexity, and thus high maximal sample frequency. We introduce the closed form relations for the design of fast IIR filters for interpolation, decimation, and QMF banks with perfect magnitude reconstruction. The design is based on the third-order half-band IIR filters and the fifth-order non minimum-phase optimal FIR filters.