vivkr
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Ken, Jerry,
Thanks for your answers. I am aware that one can achieve decent pulse response by using Bessel filters. But that is not what I am actually asking.
I am wondering if it is possible to "fix" the pulse response of say an elliptic filter with post-filtering.
If there were some halfway decent solution (one obviously cannot achieve the same response as a Bessel), then one might achieve good rejection up-front and fix the pulse response sufficiently.
The reason for asking is that I have heard from people that such things are possible (unreliable evidence), but also read in some DSP texts that one can do such a thing.
Admittedly, that's DSP, but here's what I have from "Discrete-Time Signal Processing" by Oppenheim & Schafer, 1989 edition, Sec. 7.3.2 in the chapter on "Computer-Aided Design of Discrete-Time IIR Filters":
"As an example of the utility of ...., consider the design of an allpass filter to compensate for phase nonlinearity of a linear system. This design problem is common in communications systems, where it is often necessary to "equalize" the group delay of a communications channel":
In a nutshell, is such an "equalization" of phase response of a highly selective but lousy filter (from pulse response point of view) possible using post-filtering?
Regards Vivek
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