Convention Paper
Efficient Arbitrary Sample Rate Conversion Using Zero Phase IIR Filters
AES Convention 116 · Paper 6033 · May 2004
Abstract
Modern asynchronous sample rate converters (ASRCs) are composed of an interpolation filter to increase the sample rate by an integer factor, followed by a polynomial interpolator which produces the desired output samples at arbitrary output sampling time instants. A crucial feature determining the precision of the ASRCs is the phase linearity of the interpolation filter in use. That is the main reason why traditionally easily realizable linear phase FIR filters, but not IIR filters suffering from inherent phase non-linearity, have been employed as interpolation filters, although IIR filters are more economical. This paper introduces a novel ASRC design approach which uses the zero phase IIR filtering concept to produce highly efficient, linear phase IIR interpolation filters to be used in ASRCs. The basic concept is explained and the functions of the involved units are investigated
