FIR transfer functions with arbitrary amplitude and phase, with application to the design of quasi-all-pass delay equalizers

A novel technique is presented for the design of FIR (finite-impulse-response) digital filters with simultaneous conditions on the amplitude and phase responses. The technique can be used to design any type of FIR filter, but is particularly useful for the design of quasi-all-pass phase equalizers. The method is based on a polynomial termed the arbitrary phase and amplitude polynomial. The technique was illustrated by equalizing the delay of an elliptic IIR (infinite-impulse-response) filter.<>