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Looking for a formula for intermodulation - RF Cafe Forums

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 Post subject: Looking for a formula for intermodulation
Posted: Tue May 31, 2005 5:23 pm 
I'm looking for math and formulas behind calculating intermodulation products. I know the fundamentals; a+b+c+d, a+b+c-d, etc.
What I'm trying to find are formulas which can be used to take n=number of frequencies, o=order, and calculate all the intermod. products that fall within a given range.
Any pointers to this information would be greatly appreciated.
Thank you.
I can be reached at

 Post subject:
Posted: Wed Jun 01, 2005 8:41 pm 
Site Admin
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Joined: Sun Aug 03, 2003 2:02 pm
Posts: 653
Location: Erie, PA
Greetings Geof:

I believe this paper, by Chris Arnott (whom I worked with at one time), is what you are looking for.

"A General Algorithm to Calculate Third Order Intermodulation Product Locations for any Number of Tones"

It can also be found as a link on RF Cafe on the App Notes page (1) and on the Electrical Formulas & Reference page (2).


- Kirt Blattenberger :smt024

Posted  11/12/2012