On Low-Delay Frequency-Response Masking FIR Filters

Abstract

This paper offers two main contributions to the theory of low-delay frequencyresponse masking (FRM) finite impulse response (FIR) filters. First, a thorough investigation of the low-delay FRM FIR filters and their subfilters for three different structures, referred to as narrow-, wide-, and middle-band filter structures, is given. The investigation includes discussions on delay distribution over the subfilters as well as estimation of the optimal periodicity of the periodic model filter. Second, systematic design procedures are given, with explicit formulas for distribution of the ripples and the delay to the subfilters. For each of the three structures, two design procedures are given that include joint optimization of the subfilters. The first proposal uses partly linear-phase FIR subfilters and partly low-delay FIR subfilters. Thus, it has a lower arithmetic complexity compared to the second proposal, which has exclusively low-delay FIR subfilters. The second proposal is instead more flexible and can handle a broader range of specifications. The design procedures result in low-delay FIR filters with a lower arithmetic complexity compared to previous results, for specifications with low delay and narrow transition band.

Design of recursive digital filters using frequency-response masking technique

“…The extensions of FRM technique to the design of various type of filters have also been reported in the literature. These filters include half-band filters [39,40], decimators and interpolators [41][42][43] in multirate systems, FIR differentiators [44], two-dimensional filters [19,[45][46][47], low delay FIR filters [48][49][50], filter banks [51][52][53][54][55][56][57][58],…”