I have to select a filter design topology among Butterworth, Chebyshev or Bessel. Based on your experience, can you suggest which filter is the best for GSM transmitter design?
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2\$\begingroup\$ No because: it depends. To make a GSM transmitter I might need 10 filters. Which one are you talking about ? Baseband filter ? Anti-aliasing filter ? RF filter ? LO filter ? For RF signals we mostly use tuned resonators, these aren't Butterworth, Chebyshev nor Bessel. \$\endgroup\$– BimpelrekkieCommented Jan 12, 2017 at 13:56
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\$\begingroup\$ My design focus in RF section and I am looking RF filter. \$\endgroup\$– Anil PandeyCommented Jan 12, 2017 at 14:11
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2\$\begingroup\$ I see that a couple of your earlier questions received answers that seem useful - do you realize that formally accepting answers is a good thing to do? Do you know how to do it? \$\endgroup\$– Andy akaCommented Jan 12, 2017 at 14:12
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\$\begingroup\$ Thanks for pointing this. Yes I found answers useful my design but I don't know how to accept answer, I will try to figure it out. \$\endgroup\$– Anil PandeyCommented Jan 12, 2017 at 14:16
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1\$\begingroup\$ In general the choice between Butterworth, Chebyshev or Bessel (or even Linkwitz–Riley ;-)) depends on the requirements for that filter. So what are your requirements ? And again, for RF this is usually pointless as most RF filters are tuned resonators anyway. \$\endgroup\$– BimpelrekkieCommented Jan 12, 2017 at 14:20
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Which part of the transmitter? There will be many, many filters in use in various ways and locations (some of them digital).
Loop filters in the reference timebase have very different requirements to anti alias filters after the I/Q dacs, which have different requirements to the RF BPFs ahead of the mixers and after the PAs, which have different requirements to the filters in a slow drain modulator, what have different.... Well you get the idea.
I would suggest that asking this probably means you are not ready to design a GSM transmitter, start with something very much easier.
To answer the question asked, a GSM transmitter will probably use all of those and more, they are all best in different parts of the design.
