Two-Channel Linear-Phase FIR Filter Banks Utilizing the Frequency Response Masking Approach

The frequency-response masking (FRM) approach was introduced as a means of generating narrow transition band linear-phase FIR filters with a low arithmetic complexity. This paper proposes an approach for synthesizing two-channel maximally decimated FIR filter banks utilizing the FRM technique. Compared to conventional quadrature-mirror filter (QMF) banks, the proposed banks lower significantly the overall arithmetic complexity at the expense of a somewhat increased overall filter bank delay in applications demanding narrow transition bands. Examples are included illustrating the benefits provided by the proposed filter banks.