allpass.m

Allpass filter

Many systems require phase compensation. An allpass filter provides just that without affecting magnitude response. This function creates a filter with a magnitude response of unity and n number of pole/zero complex-conjugate pairs spaced evenly starting at Fst and ending at Fed. The order of the allpass filter is 2n. The coefficients of the filter, b and a, are passed as output arguments. ALLPASS can run without the output arguments. This will display the Pole-Zero plot and the frequency response of the filter.

Syntax:
>>[b,a]=allpass(n,Fst,Fed,mag,Fs) or
>>allpass(n,Fst,Fed,mag,Fs)