I took the data of frequency noise of the functiongenerator("Marconi") and spectrum analyzer's noise from Mott's elog on Nov 13 14:37:11 2009, AdhikariLab. Thanks, Mott
To measure the noise @160Hz, two Functiongenerators are set at 160MHz, then mix two signals togather to get phase noise. Multplying the phase noise by corresponding frequencies to get frequency noise.
Assuming two ideal function generators, the freq noise is divided by sqrt(2) to get noise contributed by one function generator.
The attached graph shows frequency noise from Marconi noise, detector noise(spectrum analyzer that measured Marconi noise) , beat noise( noise from beating two beams after the cavities), and estimated noise.
VCO noise will be updated soon.