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Simulators >> RF Simulators >> How to simulate RF-LO leakage in a double-balanced mixer
https://designers-guide.org/forum/YaBB.pl?num=1240458847

Message started by aaron_do on Apr 22^nd, 2009, 8:54pm

Title: How to simulate RF-LO leakage in a double-balanced mixer
Post by aaron_do on Apr 22^nd, 2009, 8:54pm

Hi all,

I want to simulate the RF-LO leakage in a double balanced mixer. Can anybody give me hints on what sort of simulation to run?

I guess I should be running a PSS + PAC analysis with a small signal at the RF port, but because the circuit is balanced, I don't expect to see much RF-LO leakage without adding some circuit mismatch. So i'm thinking I need to run a monte-carlo analysis. Unfortunately, I don't see a statistics block in the model file and when I try to run a monte-carlo analysis I get an error saying there is no statistics block.

So I have some basic questions.

1) Can I simply add statistics to the model file and if so, how can I go about doing that?

2) Does the monte-carlo analysis also include mismatch between transistors which use the same model file?

3) Assuming I have to use monte-carlo, does anybody have a good tutorial document on how to go about setting it up?

4) If not monte-carlo, how else can I go about simulating the leakage?

thanks,
Aaron

Title: Re: How to simulate RF-LO leakage in a double-balanced mixer
Post by pancho_hideboo on Apr 23^rd, 2009, 6:30am

aaron_do wrote on Apr 22^nd, 2009, 8:54pm:

I guess I should be running a PSS + PAC analysis with a small signal at the RF port, but because the circuit is balanced, I don't expect to see much RF-LO leakage without adding some circuit mismatch. So i'm thinking I need to run a monte-carlo analysis.

I don't use monte-carlo analysis.

aaron_do wrote on Apr 22^nd, 2009, 8:54pm:

1) Can I simply add statistics to the model file and if so, how can I go about doing that?

Model files of major design kits are very helpful. Here you have to forge parameters.

aaron_do wrote on Apr 22^nd, 2009, 8:54pm:

2) Does the monte-carlo analysis also include mismatch between transistors which use the same model file?

Yes it does.

aaron_do wrote on Apr 22^nd, 2009, 8:54pm:

3) Assuming I have to use monte-carlo, does anybody have a good tutorial document on how to go about setting it up?

I don't know.
Maybe the following is not useful at all.
http://cp.literature.agilent.com/litweb/pdf/5990-3609EN.pdf

aaron_do wrote on Apr 22^nd, 2009, 8:54pm:

4) If not monte-carlo, how else can I go about simulating the leakage?

I simulate only worst case for pair mismatch. Here I forge parameters.

Title: Re: How to simulate RF-LO leakage in a double-balanced mixer
Post by aaron_do on Apr 23^rd, 2009, 7:33pm

Hi pancho_hideboo,

Quote:

I simulate only worst case for pair mismatch. Here I forge parameters.

could you elaborate on how you forge parameters?

thanks,
Aaron

Title: Re: How to simulate RF-LO leakage in a double-balanced mixer
Post by Ken Kundert on Apr 23^rd, 2009, 11:44pm

For advice on Monte Carlo, check out http://www.designers-guide.org/Modeling/montecarlo.pdf.

-Ken