Design of Digital Phase Filters Using MATLAB

Digital phase (all-pass) filters are widely used in the field of communications. This paper presents the basic relationships and characteristics of digital all-pass filters, such as magnitude and phase responses. The main applications of digital all-pass filters in communications are listed in the paper and one of them – building a notch filter based on the lattice structure of an all-pass filter is described in detail. The influence of the reflection coefficients on the filter's characteristics is considered in this paper.