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Measurements >> Phase Noise and Jitter Measurements >> single side band vs double side band
https://designers-guide.org/forum/YaBB.pl?num=1220755065

Message started by modern_analog on Sep 6^th, 2008, 7:37pm

Title: single side band vs double side band
Post by modern_analog on Sep 6^th, 2008, 7:37pm

When we plot in cadence, does it provide single side band or double side band ?

I guess if it is giving single side band only, i should multiply it by 2 and integrate over postive frequency to get the rms jitter. Is that correct?

A related question: When we measure on a spectrum analyzer, I believe we only measure Single sideband. Is that correct? In this case, again I will have to double it to integrate it.

thanks

Title: Re: single side band vs double side band
Post by pancho_hideboo on Sep 6^th, 2008, 11:30pm

modern_analog wrote on Sep 6^th, 2008, 7:37pm:

When we plot in cadence, does it provide single side band or double side band ?

What simulator do you use ?
There are many simulators working on Cadence ADE.

Cadence Spectre -->> SSB Phase Noise
Agilent ADS(RFDE) -->> SSB Phase Noise
Agilent GoldenGate -->> DSB Phase Noise

modern_analog wrote on Sep 6^th, 2008, 7:37pm:

I guess if it is giving single side band only, i should multiply it by 2 and integrate over postive frequency to get the rms jitter. Is that correct?

Correct.

modern_analog wrote on Sep 6^th, 2008, 7:37pm:

A related question: When we measure on a spectrum analyzer, I believe we only measure Single sideband. Is that correct?

Old Spectrum Analyzer or VCO analyzer show SSB Phase Noise.
But relative new Spectrum Analyzer or Signal Source Analyzer show DSB Phase Noise.
See documents of your Spectrum Analyzer.

modern_analog wrote on Sep 6^th, 2008, 7:37pm:

In this case, again I will have to double it to integrate it.

If it is SSB Phase Noise, it is yes.
And some Spectrum Analyzer have built-in jitter calculation ability from Phase Noise Spectrum measurement.

Title: Re: single side band vs double side band
Post by qad on Oct 9^th, 2008, 6:03pm

According to Ken's paper, Sds=1/2Sss, so the single-sided PSD from spectre simulation shall not be doubled for jitter calculation. Am I right?