Causal Signal processing: group delay (#007)
Channel: Digital Signal Processing
Date: 2013-10-15

The group delay defines the time a certain frequency is delayed by a filter. Ideally this should be constant and can be achieved by a Bessel filter in the analog domain. We will use this definition later to derive a digital filter with constant group delay.
http://www.hparchive.com/seminar_notes/a-127.pdf