Howtosignalprocessing
- What is group delay of FIR filter?
- How do you calculate group delay of a filter?
- Which filter should one use to get a constant group delay?
- How do you compensate for a filter delay?
What is group delay of FIR filter?
The group delay of a filter is a measure of the average time delay of the filter as a function of frequency. The group delay is defined as the negative first derivative of the filter's phase response. If the complex frequency response of a filter is H ( e j ω ) , then the group delay is.
How do you calculate group delay of a filter?
M(ω)•ejΦ(ω) = H(ω) = the DTFT of h(n) –d[Φ(ω)]/dω = group delay of the filter.
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.
How do you compensate for a filter delay?
When the shift is constant, you can correct for the delay by shifting the signal in time. Sometimes the filter delays some frequency components more than others. This phenomenon is called phase distortion. To compensate for this effect, you can perform zero-phase filtering using the filtfilt function.
