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Entry  Mon May 3 01:16:50 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup pn.png
    Reply  Tue May 4 18:40:27 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup Untitled.pngifrnoise.png
    Reply  Tue May 11 18:58:49 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup Untitled.png
       Reply  Wed May 12 02:21:56 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup pn.png
Message ID: 2914     Entry time: Wed May 12 02:21:56 2010     In reply to: 2913
Author: rana 
Type: HowTo 
Category: Electronics 
Subject: Marconi phase noise measurement setup 

Finally got the 3-cornered-hat measurement of the IFRs done. The result is attached.

s12, s23, & s31, are the beat signals between the 3 signal generators.

s1, s2, & s3 are the phase noise of the individual generators made by the following matlab calculation:

%% Do the hat
s1 = sqrt((s12.^2  + s31.^2 - s23.^2) / 2);
s2 = sqrt((s12.^2  + s23.^2 - s31.^2) / 2);
s3 = sqrt((s31.^2  + s23.^2 - s12.^2) / 2);

As you can see, there is now an estimate of the individual noises. We can do better by doing some fitting of the residuals.

The real test will be to replace the noise one here with the good Wenzel oscillator and see how well we can estimate its noise. If the 11 MHz crystals don't show up, I can just try this with the 21.5 MHz one for the PSL.

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