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Recording one scan with Phase Cal ON for 19 minutes using vgos_recorder.py. Followed by another scan of just a couple of minutes with Phase Cal off for comparison. Inifile configured as:
mkdir /mnt/vbsPcal/
vbs_fs -n 4 -I *pcal_*2205 /mnt/vbsPcal/
ls -l /mnt/vbsPcal/
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46227
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46228
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46229
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46230
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46233
-rw-r–r– 0 observer observer 15G May 22 16:13 pcal_off_2205_Hb_No0001_46234
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46227
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46228
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46229
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46230
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46233
-rw-r–r– 0 observer observer 137G May 22 16:10 pcal_on_2205_Hb_No0001_46234
First need to change PythonPath every-time you open a new terminal, otherwise is using DifX defaults one:
export PYTHONPATH=/usr/lib/python3.4
The processing takes 3 steps: 1- Running the software spectrometer to see the spectrum of the signal recorded (swspec) 2- Making a first estimate of the pcal measurements (calculatePcalCpp) 3- Running the tracking software (sctracker).
1. Take the inifile.ini that is in the directory and prepare it for the scan you want to process. There are basically 2 settings you can modify: Channel from 1 to 8. I did the recording with 8 channels
IF from A to F. We recorded the data from the 6 boards in the dbbc3. So for a total of 6×8 channels = 48.
UseFile1Channel = 1 # Change this value from 1 to 8, one per channel BaseFilename1 = p190522_Hb_VDIF_If000A_%fftpoints%pt_%integrtime%s_ch%channel% # Modify IF000A to A/B/C/D/E/F to cover all the boards.
You should end up with 48 spectra data files.
2. Check the quality of the spectrum. I have written several Python scripts to provide a quick validation of the recorded data. -bw sets the bandwidth -f0 sets the minimum frequency to search for the peak -f1 sets the maximum frequency to search for the peak -p plots the output - don't put anything if you don't need
- python3 checkSpectra.py p190522_Hb_VDIF_If000A_320000pt_5s_ch1_swspec.bin -bw 32e6 -f0 4e6 -f1 6e6 -p - python3 calculatePcalCpp.py p190522_Hb_VDIF_If000A_320000pt_5s_ch1_swspec.bin -bw 32e6 -f0 4.9e6 -f1 5.1e6
The calculatePcalCpp will provide a set of polynomials that will be used for the tracking software to study the Phase Cal tone. Example: -rw-r–r– 1 observer observer 75 May 23 12:07 p190522_Hb_VDIF_If000A_320000pt_5s_ch1.poly2.txt -rw-r–r– 1 observer observer 50 May 23 12:07 p190522_Hb_VDIF_If000A_320000pt_5s_ch1.X1cfs.txt
3. Configure and run sctracker Edit inifileHb and modify the following fields # Input file . InputSource = /mnt/vbsPcal/pcal_on_2205_Hb_No0001_46227 # Here you select channel 1 to 8 UseChannel = 1 # Select Cpp text file . PhasePolyCpmFile = p190522_Hb_VDIF_If000A_320000pt_5s_ch1.poly2.txt # Select Cpp text file . PhasePolyCppFile = p190522_Hb_VDIF_If000A_320000pt_5s_ch1.poly2.txt # Output file name . . BaseFilename = p190519_Hb_VDIF_If000A_%fftpoints%pt_%integrtime%s_ch%channel%
Run the sctracker as: - sctracker inifileHb
Once sctracker has finished, which can take several hours, it produces several output files. The most important one is p190519_Hb_VDIF_If000A_3200000pt_5s_ch1_tone0.bin
Once it has finished please remove the scscec.bin because it is very large and we better save some storage space. rm p190519_Hb_VDIF_If000A_3200000pt_5s_ch1_scspec.bin