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Simulators >> RF Simulators >> ring VCO phase noise is positive
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Message started by 880321 on Dec 12^th, 2012, 7:57pm

Title: ring VCO phase noise is positive
Post by 880321 on Dec 12^th, 2012, 7:57pm

I run the PSS+Pnoise sim using spectreRF for a ring vco, I found that the phase is positive @ low offset,eg 100Hz
phase noise:
20dBc/Hz@10Hz
-70dBc/Hz@100KHz
but L(f)=10log(Pn/Ps), how could this be positive?

Best regards
haitao

Title: Re: ring VCO phase noise is positive
Post by Ken Kundert on Dec 12^th, 2012, 8:48pm

Check out page 31 in An Introduction to Cyclostationary Noise.

-Ken