A New Method for Design of Selective Digital Iir Filters With Arbitrary Phase

Abstract

In this paper the design of selective digital filters that consists of a parallel connection of two all-pass sub-filters is presented. The phase of these filters has given an arbitrary shape ϕ(ω) in both pass-band and stop-band. The proposed method allows the calculation of selective filters with elliptic-like magnitude characteristic. Equations given in the paper are general and suitable for design of filters with arbitrary phase. The efficiency of the method is demonstrated on design of filters with piecewise linear and quadratic phases.