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Simulators >> RF Simulators >> Mixer IIP3 sim
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Message started by salty on Jan 20^th, 2011, 10:44am

Title: Mixer IIP3 sim
Post by salty on Jan 20^th, 2011, 10:44am

Trying to set up an iip3 sim for a mixer. Confused by a couple of results. I set things up according to rapid iip2/iip3 paper. Set the LO harmonics to 3 and rf input signal to 3. For qpac, set max clock order to 2. Result is as expected. Not, if I set max clock order in qpac to 4, I get about 5 dB better iip3. If I increase the harmonics in qpss, results get a few db worse. Any guidlines on setting these parameters?

Using spectre qpss/qpac

Title: Re: Mixer IIP3 sim
Post by Andrew Beckett on Jan 21^st, 2011, 11:19pm

I presume you're not actually using RapidIP3, because that would be done using PSS (with just LO enabled) and then PAC in RapidIP3 mode.

Without knowing what the behaviour of the circuit is, and what the spectral response is, it's very hard to give generic guidelines. I think you'll need to give some more details, and probably some pictures of the response you're getting from QPSS and QPAC.

Regards,

Andrew.