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Entry  Wed Apr 22 11:48:30 2015, manasa, Summary, General, Delay line frequency discriminator for FOL error signal 
    Reply  Wed Apr 22 14:56:18 2015, manasa, Summary, General, Delay line frequency discriminator for FOL error signal 
       Reply  Mon May 4 10:21:09 2015, manasa, Summary, General, Delay line frequency discriminator for FOL error signal DFD.pngDFD_resp.png
       Reply  Mon May 4 12:42:34 2015, manasa, Summary, General, Delay line frequency discriminator for FOL error signal DFD_cosfit.png
          Reply  Mon May 18 14:46:20 2015, manasa, Summary, General, Delay line frequency discriminator for FOL error signal DFDnoise.pngDFDnoise_AC.pngFreqResp.pngDFD.zip
Message ID: 11272     Entry time: Mon May 4 12:42:34 2015     In reply to: 11236     Reply to this: 11300
Author: manasa 
Type: Summary 
Category: General 
Subject: Delay line frequency discriminator for FOL error signal 

Koji suggested that I make a cosine fit for the curve instead of a linear fit.

I fit the data to V(f) = A + B cos(2\pi f_{b}L/v) 
where L - cable length asymmetry (27 cm) , fb - beat frequency and v - velocity of light in the cable (2*10m/s)

The plot with the cosine fit is attached. 

Fit coefficients (with 95% confidence bounds):
       A =      0.4177  (0.3763, 0.4591)
       B =       2.941  (2.89, 2.992)

Attachment 1: DFD_cosfit.png  30 kB  | Hide | Hide all
DFD_cosfit.png
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