IIR filter group delay

1. What is group delay of IIR filter?
2. How do you calculate group delay of a filter?
3. What is phase delay and group delay in filters?
4. Which filter should one use to get a constant group delay?

What is group delay of IIR filter?

The so-called “group delay” is simply the time lag between the envelope of input burst and the envelope of the amplitude of the output burst. So, group delay means a propagation delay through a filter, measured on the envelope of the signal.

How do you calculate group delay of a filter?

M(ω)•e^jΦ(ω) = H(ω) = the DTFT of h(n) –d[Φ(ω)]/dω = group delay of the filter.

What is phase delay and group delay in filters?

one last important difference: the phase delay at some frequency f is the time delay of the phase of the quasi-sinusoidal signal of frequency f passed through the filter. the group delay is the time delay of the envelope or "group" of the quasi-sinusoid.

Which filter should one use to get a constant group delay?

By far the most common applications for FIR filters are linear phase FIR filters because of the benefit of constant group delay which is the result of linear phase.