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Entry  Wed Jun 13 19:00:26 2012, Sarah, DailyProgress, Laser, Transfer Functions 12x
    Reply  Fri Jun 22 22:34:28 2012, tara, DailyProgress, NoiseBudget, RIN coupling to Frequency noise 
    Reply  Wed Jun 27 18:51:56 2012, Sarah, DailyProgress, Laser, Transfer Functions Slide1.pngtf_oa_calc_measured.pngTF_allfreq.pngTF_fit_allfreq.pngnb_allfreq.png
       Reply  Fri Jul 6 18:59:49 2012, tara, DailyProgress, Laser, Transfer Functions IMG_1447.jpgRIN_Fnoise.pngRIN_Fnoise.png
          Reply  Tue Jul 10 02:55:37 2012, tara, DailyProgress, Laser, Transfer Functions 
             Reply  Mon Jul 16 19:08:34 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) 
                Reply  Tue Jul 17 19:05:32 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) 7x
                   Reply  Tue Jul 24 17:02:35 2012, Sarah, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) 8x
                      Reply  Fri Aug 3 02:46:15 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) RIN_coupling_2012_08_03.pngRIN_coupling.fig
                         Reply  Tue Aug 13 21:45:51 2013, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) farsi_2013_08_13.pngfarsi_2013_08_13.figRIN_TO_algaas.pngRIN_TO_algaas.fig
                            Reply  Fri Aug 16 04:35:58 2013, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) RIN_req_algaas.pngRIN_req_algaas.fig
                            Reply  Thu Aug 22 13:36:19 2013, tara, DailyProgress, NoiseBudget, Transfer Functions (RIN to Frequency noise via photothermal) fasi_2013_08_22.pngFarsi_compare.fig
          Reply  Wed Jul 11 11:13:38 2012, Sarah, DailyProgress, Laser, Transfer Functions 7x
          Reply  Sun Jul 15 23:20:32 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (power fluctuation to Frequency noise via photothermal effect) Farsi_compare.pngFarsi_compare.fig
             Reply  Thu Jul 19 03:01:26 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (power fluctuation to Frequency noise via photothermal effect) Farsi_compare.pngFarsi_compare.fig
                Reply  Thu Jul 19 23:56:45 2012, rana, DailyProgress, NoiseBudget, Transfer Functions (power fluctuation to Frequency noise via photothermal effect) 
                   Reply  Fri Jul 20 01:32:45 2012, tara, DailyProgress, NoiseBudget, Transfer Functions (power fluctuation to Frequency noise via photothermal effect) 
Message ID: 1021     Entry time: Tue Jul 17 19:05:32 2012     In reply to: 1020     Reply to this: 1029
Author: tara 
Type: DailyProgress 
Category: NoiseBudget 
Subject: Transfer Functions (RIN to Frequency noise via photothermal) 

Tara and I re-measured the transfer function coupling the RIN to frequency noise at five different power levels.

We were having problems with the ACAV gain at low powers, so we chose appropriate attenuation through an OD filter to compensate. 

The following plot shows the TF's measured, with their corresponding ACAV power levels:

TF_compare.png

The transfer functions measured at 2.2mW, and 1.9mW were measured with a .15 OD filter. Those measured at 1.77mW, 1.6mW, and 1.42mW were measured with a .10 OD filter. 

As shown in the plot, the magnitudes of the transfer functions measured at different power levels match up quite nicely, confirming the validity of the transfer function. The phase plots are pretty consistent, with slight variation up to 20 degrees at higher frequencies.

I converted the above transfer function magnitudes to units of [Hz/Watt] and plotted the results with the calculation using Cerdonio's result:

tf_compare_cerdonio.png

The main source of error between the calculated and measured transfer function is from the voltage to power calibration. We will re-measure this and see if a result closer to the calculation is achieved. Since the measured transfer functions are all fairly consistent with each other in magnitude, I used the transfer function measured at 2.2mW and calculated the residuals for the calculation w/ Cerdonio's results:

residuals.png

I attached the raw data, where the first column of each .mat variable is frequency and the second is dB for magnitude variables and degrees for phase variables.

Attachment 4: residuals.fig  11 kB  Uploaded Tue Jul 17 20:36:06 2012
Attachment 5: tf_compare_cerdonio.fig  67 kB  Uploaded Tue Jul 17 20:36:18 2012
Attachment 6: TF_compare.fig  43 kB  Uploaded Tue Jul 17 20:36:29 2012
Attachment 7: TF.mat  25 kB  Uploaded Tue Jul 17 20:40:37 2012
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