Well I am in similar situation. I need to measure Residual Phase Noise.
I did some serching and find some materials like the one show below.
In your case probably the direct Phase Noise measurement method can be perform with Spectrum Analyzer.
Your are using E4407B ESA-E, check it you do not have Noise Figure option on the Spectrum Analyzer (SA), that will simplify your problem.
In my case direct Phase Noise measurement do not work and I need to use Phase Detector technique.
I have a lot of problem with that.
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