procedure GroupDelay(GrpDelay: TVec; Num: TVec; Den: TVec; ZeroPadding: Integer);
Computes the group delay of IIR filters.
| # | Name | Type | Description |
|---|---|---|---|
| 1 | GrpDelay | TVec | source TVec |
| 2 | Num | TVec | source TVec |
| 3 | Den | TVec | source TVec |
| 4 | ZeroPadding | Integer |
Result: stored in self (calling object)
Remarks:
Num holds the numerator and Den the denominator of the transfer function for which the group delay should be computed. Den can be nil. Zeropadding defines the amount of zero padding applied with FFT. The result is placed in GrpDelay. Group delay is the first derivate of continuous phase: g = (d/dw)Phase, where w is the frequency ([1] p. 201).
References:
[1] Understanding digital signal processing, Richard G. Lyons, Prentice-Hall, 2001. Advanced sampling techniques