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Diffstat (limited to 'gr-radio-astronomy/src/python/usrp_psr_receiver.help')
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diff --git a/gr-radio-astronomy/src/python/usrp_psr_receiver.help b/gr-radio-astronomy/src/python/usrp_psr_receiver.help deleted file mode 100644 index 5801f3fbb..000000000 --- a/gr-radio-astronomy/src/python/usrp_psr_receiver.help +++ /dev/null @@ -1,111 +0,0 @@ -This program is used to analyse pulsars of known parameters. It contains - both a post-detector spectral display, and a "pulse profile" display. - It has a built-in de-dispersion filter that will work up to DM=100 for - 21cm observing, and up to DM=5 for 327Mhz observing. - -The program takes the following options: - - --rx-subdev-spec which USRP Rx side? A or B - - --decim USRP decimation rate use either 64 or 128 - - --freq USRP daughtercard frequency - - --observing Actual observing frequency (default is to use the - setting for --freq) - - --avg Averaging setting for spectral display--higher numbers - equal more averaging. 25 to 40 is typical. - - --favg Pulse folding averaging. 2 to 5 is typical. - - --gain USRP daughtercard gain control - - --reflevel Reference level on pulse profile display - - --lowest Lowest spectral bin that is considered valid, in Hz - - --longitude Observer longitude: West is negative - - --latitude Observer latitude: South is negative - - --fft_size Size of FFT for post-detector spectrum: default is 1024 - - --threshold Threshold (dB) to be considered a spectral "peak" - This is relative to the average spectral level - - --lowpass Low pass frequency for post-detector spectral display - 20-100 is typical - - --prefix Filename prefix to use for recording files - Default is ./ - - --pulsefreq The frequency of the expected pulses - For sentimental reasons, this defaults to 0.748Hz - - --dm The DM - - --doppler The doppler shift, as a ratio - - --divbase The base of the Y/Div menu in pulsar display - - --division The initial Y/Div in pulsar display - -DM, Doppler, Gain, Frequency, and the averaging parameters can all be - changed using the GUI at runtime. - -If latitude and longitude are set correctly, and the system time is - correct, then the current LMST is displayed below the frequency - input, updated once per second. - -Moving the mouse in the post-detector spectrum display shows you that - point in the post-detector spectrum, both frequency and signal level. - -The post-detector spectrum is analysed, with results shown below - "Best freq". It shows the spectral peaks, and computes their relationship. - It shows the harmonic compliance among the peaks, as well as the average - peak-to-peak distance. - - -Here's a complete example for observing a pulsar with a frequency of - 1.35Hz, at 431.5Mhz, using an IF of 10.7Mhz, and a DM of 12.431, using - 1Mhz observing bandwidth: - -./usrp_psr_receiver.py --freq 10.7e6 --decim 64 --dm 12.431 --avg 35 \ - --pulsefreq 1.35 --fft_size 2048 --lowest 1.00 --gain 75 --threshold 11.5 \ - --observing 431.5e6 --reflevel 200 --division 100 --divbase 10 --favg 3 \ - --lowpass 20 --longitude -76.02 --latitude 44.95 - -Since the observed pulsar is at 1.35Hz, a lowpass cutoff for the - post-detector spectral display of 20Hz will be adequate. We - tell the spectral analyser to use a threshold of 11.5dB above - average when analysing spectral data, and set the epoch folder - averager (pulse profile display) to use an average from 3 samples. - Notice that our actual USRP/Daughtercard frequency is 10.7Mhz, while - our observing frequency is 431.5Mhz--this is important in order for - the DM de-dispersion calculations to be correct. We also set our - latitude and longitude, so that logfiles and the LMST display - will have the correct LMST in them. - -The entire complex baseband can be recorded, if the "Recording baseband" - button is pressed. Filenames are generated dynamically, and a header - file is produced giving observation parameters. The baseband data are - recorded as octet pairs: one for I and one for Q. Pressing the button again - turns off baseband recording. This baseband is "raw", so it will - not have been de-dispersed. The data rate will be whatever the - USRP was programmed to at the time (based on --decim). - - The files are: YYYYMMDDHHMM.pdat and YYYYMMDDHHMM.phdr - - The .phdr file contains ASCII header information describing the - contents of the .pdat file. - -Similarly the raw, pre-folded, band-limited post-detector "audio" data can be - recorded using the "Record Pulses" button. The data rate for these is - currently 20Khz, recorded as short integers. Just like baseband recording, - pressing the button again turns off pulse recording. - - The files are: YYYYMMDDHHMM.padat and YYMMDDHHMM.pahdr - - The .pahdr file is ascii text providing information about the contents - of the corresponding .padat file. |