PSI simulations
These are simulated visibility data sets in Measurement Set format, as needed to test the operation of the CBF-SDP interface and the real-time signal displays.
These simulations generate fully time-sampled, high number of spectral channel observations using the simulated Prototype System Integration (PSI) test arrays: a small number of antennas or stations (between 4 and 8), with a large number of frequency channels (of order 10000).
The simulation currently does:
10 minutes of 0.28s integrations
six antennas chosen to be close to the centre but to give baselines upto 200m
50% fractional bandwidth: centre frequency 1.369GHz +/- 0.5 * 1.369GHz
The simulation requires a large amount of memory, primality because of inefficiencies in the RASCIL visibility format. We expect to reduce these over time. The best Dask setup on Alaska P3 is to use one worker and a large number of threads (up to 64).
Simulate time and frequency dense PSI observations
usage: mid_write_psi.py [-h] [--rmax RMAX] [--configuration CONFIGURATION]
[--antennas [ANTENNAS ...]] [--badantenna BADANTENNA]
[--howbad HOWBAD] [--ra RA]
[--declination DECLINATION] [--band BAND]
[--nchan NCHAN] [--nspw NSPW]
[--channel_width CHANNEL_WIDTH]
[--integration_time INTEGRATION_TIME]
[--time_range TIME_RANGE TIME_RANGE]
[--image_pol IMAGE_POL] [--vis_pol VIS_POL]
[--duration DURATION] [--results RESULTS]
[--msname MSNAME] [--split SPLIT]
[--nthreads NTHREADS] [--processes PROCESSES]
[--memory MEMORY] [--nworkers NWORKERS]
[--use_dask USE_DASK] [--interface INTERFACE]
Named Arguments
- --rmax
Maximum distance of dish from centre (m)
Default: 200.0
- --configuration
MID Configuration: MID | MEERKAT+
Default: “MID”
- --antennas
antenna names to include (default is all)
- --badantenna
Bad antenna
Default: -1
- --howbad
How many meters to move bad antenna
Default: 1
- --ra
Right ascension of phase centre (degrees)
Default: 0.0
- --declination
Declination of phase centre (degrees)
Default: -55.0
- --band
Band B1LOW | B1 | B2 | Ku
Default: “B2”
- --nchan
Number of frequency channels
Default: 1024
- --nspw
Number of spectral windows
Default: 8
- --channel_width
Channel bandwidth (Hz) (default is to calculate from frequency
- --integration_time
Integration time (s)
Default: 0.14
- --time_range
Time range in hour angle
Default: [0, 0.16667]
- --image_pol
RASCIL polarisation frame for image: stokesI | stokes IQ | stokesIQUV
Default: “stokesIQUV”
- --vis_pol
RASCIL polarisation frame for visibility: linear | linearnp
Default: “linear”
- --duration
Type of duration: long or medium or short
Default: “long”
- --results
Directory for results
Default: “./”
- --msname
Root name of MS (i.e. without .ms)
Default: “sim_mid_psi”
- --split
In concat, type of tree e.g. 2->binary
Default: 2
- --nthreads
Number of threads per worker
Default: 1
- --processes
Number of processes per worker
Default: 1
- --memory
Memory per worker (GB)
- --nworkers
Number of workers
Default: 4
- --use_dask
Use dask processing?
Default: “True”
- --interface
Network interface
Default: “ib0”
Todo
Insert todo’s here