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Message ID: 2376     Entry time: Thu Jul 25 11:15:40 2019
Author: Nathan Holland 
Type: DailyProgress 
Category: 2micronLasers 
Subject: Phase Noise of Moku. 

Attached are the results from measuring the phase noise of the Moku with a SRS DS345, which was the available signal generator in the QIL lab. Attachment 1 is the estimate of the Moku phase noise, with attachement 2 containing the data. Attachment 3 shows the data this was obtained from, and attachment 4 the experimental setup used to measure this. 15.625 kHz is the maximum frequency that the Moku will let you acquire two channels of data, in the phasemeter setup. In this setup I generated a 20 MHz signal on the DS345. This was then split, via a T piece, and sent through cables of length 0.6414 m to inputs 1 and 2 of the Moku. Concurrently the 10 MHz synchronisation signal was sent, also through a 0.6414 m cable, with an additional elbow piece, from the DS345 output to the Moku 10 MHz input. The phase difference between input 1 and input 2, shown in yellow orange in attachment 3, should be sqrt(2) times the phase noise of the Moku.


Attachment 5 shows the same setup, but with the spectrum straight from the Moku, which can be acquired at a maximum speed of 488 Hz. They are relatively consistent in the overlapping frequencies. Attachment 6 shows what happens when the 10 MHz synchronisation is removed. The low frequency performance of individual channels suffers but there is not a substantial change in the difference, yellow orange.


Attachment 8 shows the phase difference performance at 10 MHz, with attachment 7 showing the setup for this measurment. The cable length for this measurment was 0.9993 m for all paths. Again the difference, yellow orange, is comparable to other measurements.

Attachment 1: 20190725__Moku_phase_noise_SRS-DS345.pdf  52 kB  Uploaded Thu Jul 25 12:17:24 2019  | Hide | Hide all
Attachment 2: Moku_Phase_Noise_Estimate__20190724.csv  381 kB  Uploaded Thu Jul 25 12:19:10 2019
Attachment 3: 20190725__Moku_phase_diff_fast_1.pdf  118 kB  Uploaded Thu Jul 25 12:19:17 2019  | Hide | Hide all
Attachment 4: 20190725__Moku_phase_noise_setup.pdf  17 kB  Uploaded Thu Jul 25 12:44:24 2019  | Hide | Hide all
Attachment 5: Moku_phasediff_SRSDS345_20MHz_Sync_Screenshot.png  808 kB  Uploaded Thu Jul 25 12:45:06 2019  | Hide | Hide all
Attachment 6: Moku_phasediff_SRSDS345_20MHz_NoSync_Screenshot.png  801 kB  Uploaded Thu Jul 25 12:45:15 2019  | Hide | Hide all
Attachment 7: 20190725__Moku_10MHz_phase_diff_setup.pdf  16 kB  Uploaded Thu Jul 25 12:49:13 2019  | Hide | Hide all
Attachment 8: Moku_phasediff_SRSDS345_10MHz_SyncSig_Screenshot.png  955 kB  Uploaded Thu Jul 25 12:49:28 2019  | Hide | Hide all
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