def find_t_sys_gain(pulsar, obsid, beg=None, t_int=None, p_ra=None, p_dec=None,\
obs_metadata=None, query=None, trcvr="/group/mwaops/PULSAR/MWA_Trcvr_tile_56.csv"):
"""
Finds the system temperature and gain for an observation.
A function snippet originally written by Nick Swainston - adapted for general VCS use.
Parameters:
-----------
pulsar: str
the J name of the pulsar. e.g. J2241-5236
obsid: int
The observation ID. e.g. 1226406800
beg: int
The beginning of the observing time
t_int: float
The total time that the target is in the beam
p_ra: str
OPTIONAL - the target's right ascension
p_dec: str
OPTIONAL - the target's declination
obs_metadata: list
OPTIONAL - the array generated from mwa_metadb_utils.get_common_obs_metadata(obsid)
query: object
OPTIONAL - The return of the psrqpy function for this pulsar
trcvr: str
The location of the MWA receiver temp csv file. Default = '/group/mwaops/PULSAR/MWA_Trcvr_tile_56.csv'
Returns:
--------
t_sys: float
The system temperature
t_sys_err: float
The system temperature's uncertainty
gain: float
The system gain
gain_err: float
The gain's uncertainty
"""
#get ra and dec if not supplied
if p_ra is None or p_dec is None and query is None:
logger.debug("Obtaining pulsar RA and Dec from ATNF")
query = psrqpy.QueryATNF(psrs=[pulsar], loadfromdb=ATNF_LOC).pandas
p_ra = query["RAJ"][0]
p_dec = query["DECJ"][0]
elif query is not None:
query = psrqpy.QueryATNF(psrs=[pulsar], loadfromdb=ATNF_LOC).pandas
p_ra = query["RAJ"][0]
p_dec = query["DECJ"][0]
#get metadata if not supplied
if obs_metadata is None:
logger.debug("Obtaining obs metadata")
obs_metadata = mwa_metadb_utils.get_common_obs_metadata(obsid)
obsid, obs_ra, obs_dec, _, delays, centrefreq, channels = obs_metadata
#get beg if not supplied
if beg is None or t_int is None:
logger.debug("Calculating beginning time for pulsar coverage")
beg, _, t_int = find_times(obsid, pulsar, beg=beg)
#Find 'start_time' for fpio - it's usually about 7 seconds
#obs_start, _ = mwa_metadb_utils.obs_max_min(obsid)
start_time = beg - int(obsid)
#Get important info
trec_table = Table.read(trcvr, format="csv")
ntiles = 128 #TODO actually we excluded some tiles during beamforming, so we'll need to account for that here
beam_power = fpio.get_beam_power_over_time([obsid, obs_ra, obs_dec, t_int, delays,\
centrefreq, channels],\
np.array([[pulsar, p_ra, p_dec]]),\
dt=100, start_time=start_time)
beam_power = np.mean(beam_power)
# Usa a primary beam function to convolve the sky temperature with the primary beam
# (prints suppressed)
sys.stdout = open(os.devnull, 'w')
_, _, Tsky_XX, _, _, _, Tsky_YY, _ = pbtant.make_primarybeammap(
int(obsid), delays, centrefreq * 1e6, 'analytic', plottype='None')
sys.stdout = sys.__stdout__
#TODO can be inaccurate for coherent but is too difficult to simulate
t_sky = (Tsky_XX + Tsky_YY) / 2.
# Get T_sys by adding Trec and Tsky (other temperatures are assumed to be negligible
t_sys_table = t_sky + submit_to_database.get_Trec(trec_table, centrefreq)
t_sys = np.mean(t_sys_table)
t_sys_err = t_sys * 0.02 #TODO: figure out what t_sys error is
logger.debug("pul_ra: {} pul_dec: {}".format(p_ra, p_dec))
_, _, zas = mwa_metadb_utils.mwa_alt_az_za(obsid, ra=p_ra, dec=p_dec)
theta = np.radians(zas)
gain = submit_to_database.from_power_to_gain(beam_power,
centrefreq * 1e6,
ntiles,
coh=True)
logger.debug("beam_power: {} theta: {} pi: {}".format(
beam_power, theta, np.pi))
gain_err = gain * ((1. - beam_power) * 0.12 + 2. *
(theta / (0.5 * np.pi))**2. + 0.1)
# Removed the below error catch because couldn't find an obs that breaks it
#sometimes gain_err is a numpy array and sometimes it isnt so i have to to this...
#try:
# gain_err.shape
# gain_err = gain_err[0]
#except:
# pass
return t_sys, t_sys_err, gain, gain_err
def main():
usage = "Usage: %prog [options]\n"
usage += "\tCreates an image of the 408 MHz sky (annoted with sources) that includes contours for the MWA primary beam\n"
usage += "\tThe beam is monochromatic, and is the sum of the XX and YY beams\n"
usage += "\tThe date/time (UT) and beamformer delays must be specified\n"
usage += "\tBeamformer delays should be separated by commas\n"
usage += "\tFrequency is in MHz, or a coarse channel number (can also be comma-separated list)\n"
usage += "\tDefault is to plot centered on RA=0, but if -r/--racenter, will center on LST\n"
usage += "\tContours will be plotted at %s of the peak\n" % contourlevels
usage += "\tExample:\tpython primarybeammap.py -c 98 --beamformer=1,0,0,0,3,3,3,3,6,6,6,6,9,9,9,8 \n\n"
parser = OptionParser(usage=usage)
parser.add_option('-c',
'--channel',
dest='channel',
default=None,
help='Center channel(s) of observation')
parser.add_option('-f',
'--frequency',
dest='frequency',
default=None,
help='Center frequency(s) of observation [MHz]')
parser.add_option('-b',
'--beamformer',
dest='delays',
default="0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0",
help='16 beamformer delays separated by commas')
parser.add_option('-D',
'--date',
dest='date',
default=None,
help='UT Date')
parser.add_option('-t',
'--time',
dest='time',
default=None,
help='UT Time')
parser.add_option('-g', '--gps', dest='gps', default=None, help='GPS time')
parser.add_option(
'-m',
'--model',
dest='model',
default='analytic',
help='beam model: analytic, advanced, full_EE, full_EE_AAVS05')
parser.add_option(
'-p',
'--plottype',
dest='plottype',
default='beamsky',
help='Type of plot: all, beam, sky, beamsky, beamsky_scaled')
parser.add_option('--title', dest='title', default=None, help='Plot title')
parser.add_option('-e',
'--ext',
dest='extension',
default='png',
help='Plot extension [default=%default]')
parser.add_option('-r',
'--racenter',
action="store_true",
dest="center",
default=False,
help="Center on LST?")
parser.add_option('-s',
'--sunline',
dest="sunline",
default="1",
choices=['0', '1'],
help="Plot sun [default=%default]")
parser.add_option('--tle',
dest='tle',
default=None,
help='Satellite TLE file')
parser.add_option('--duration',
dest='duration',
default=300,
type=int,
help='Duration for plotting satellite track')
parser.add_option('--size',
dest='size',
default=1000,
type=int,
help='Resolution of created beam file')
parser.add_option('--dir',
dest='dir',
default=None,
help='output directory')
parser.add_option('-v',
'--verbose',
action="store_true",
dest="verbose",
default=False,
help="Increase verbosity of output")
(options, args) = parser.parse_args()
if options.dir is not None:
mkdir_p(options.dir)
if options.frequency is not None:
if (',' in options.frequency):
try:
frequency = list(map(float, options.frequency.split(',')))
except ValueError:
logger.error("Could not parse frequency %s\n" %
options.frequency)
sys.exit(1)
else:
try:
frequency = float(options.frequency)
except ValueError:
logger.error("Could not parse frequency %s\n" %
options.frequency)
sys.exit(1)
else:
frequency = options.frequency
if options.channel is not None:
if (',' in options.channel):
try:
channel = list(map(float, options.channel.split(',')))
except ValueError:
logger.error("Could not parse channel %s\n" % options.channel)
sys.exit(1)
else:
try:
channel = float(options.channel)
except ValueError:
logger.error("Could not parse channel %s\n" % options.channel)
sys.exit(1)
else:
channel = options.channel
if options.delays is not None:
try:
if (',' in options.delays):
delays = list(map(int, options.delays.split(',')))
else:
delays = 16 * [int(options.delays)]
except ValueError:
logger.error("Could not parse beamformer delays %s\n" %
options.delays)
sys.exit(1)
else:
delays = options.delays
extension = options.extension
plottype = options.plottype
model = options.model
if model not in [
'analytic', 'advanced', 'full_EE', 'full_EE_AAVS05', '2016',
'2015', '2014'
]:
logger.error("Model %s not found\n" % model)
sys.exit(1)
if plottype not in ['all', 'beam', 'sky', 'beamsky', 'beamsky_scaled']:
logger.error("Plot type %s not found\n" % plottype)
sys.exit(1)
gpsstring = options.gps
gps = int(gpsstring)
if (len(delays) < 16):
logger.error("Must supply 1 or 16 delays\n")
sys.exit(1)
if (frequency is None):
if (channel is not None):
if (isinstance(channel, list)):
frequency = list(
1.28 * numpy.array(channel)
) # multiplication by 1e6 is done later at line Convert to Hz
else:
frequency = 1.28 * channel # multiplication by 1e6 is done later at line Convert to Hz
if frequency is None:
logger.error("Must supply frequency or channel\n")
sys.exit(1)
if (isinstance(frequency, int) or isinstance(frequency, float)):
frequency = [frequency]
frequency = numpy.array(frequency) * 1e6 # Convert to Hz
for freq in frequency:
print('frequency', freq)
result = make_primarybeammap(gps,
delays,
freq,
model=model,
plottype=plottype,
extension=extension,
resolution=options.size,
directory=options.dir)
if (result is not None):
print("Wrote %s" % result)
#!/usr/bin/env python """ Script for calculating A/T for MWA Script calling function primarybeammap_tant.py to calculate antenna temperature according to MWA beam model (analytic, AEE or FEE) and scaled Haslam map Example usage: python ./mwa_sensitivity.py -b 18,13,8,3,17,12,7,2,16,11,6,1,15,10,5,0 -c 169 -p all -g 0 -m full_EE python ./mwa_sensitivity.py -c 169 -p all -g 0 -m full_EE Starting version by Marcin Sokolowski main task is: make_primarybeammap() This is the script interface to the functions and modules defined in MWA_Tools/src/primarybeamap.py """ import errno import math from optparse import OptionParser import os import sys from astropy.io import fits as pyfits import numpy as np from mwa_pb.primarybeammap_tant import contourlevels, get_beam_power, logger, make_primarybeammap from mwa_pb import mwa_sweet_spots from mwa_pb import metadata
def calculate_sensitivity(freq,
delays,
gps,
trcv_type,
T_rcv,
size,
dirname,
model,
plottype,
extension,
pointing_az_deg=0,
pointing_za_deg=0,
add_sources=False,
zenithnorm=True,
antnum=128,
inttime=120,
bandwidth=1280000):
freq_mhz = freq / 1e6
print 'frequency=%.2f -> delays=%s' % (freq, delays)
# if trcv_type',default='trcv_from_skymodel_with_err
if trcv_type != "value":
if trcv_type == "trcv_from_skymodel_with_err":
T_rcv = trcv_from_skymodel_with_err(freq_mhz)
print "T_rcv calculated from trcv_from_skymodel_with_err = %.2f K" % (
T_rcv)
result = make_primarybeammap(gps,
delays,
freq,
model=model,
plottype=plottype,
extension=extension,
resolution=size,
directory=dirname,
zenithnorm=zenithnorm,
b_add_sources=add_sources)
(beamsky_sum_XX, beam_sum_XX, Tant_XX, beam_dOMEGA_sum_XX, beamsky_sum_YY,
beam_sum_YY, Tant_YY, beam_dOMEGA_sum_YY) = result
beams = get_beam_power(delays,
freq,
model=model,
pointing_az_deg=pointing_az_deg,
pointing_za_deg=pointing_za_deg,
zenithnorm=zenithnorm)
gain_XX = beams['XX'] / (beam_dOMEGA_sum_XX / (4.00 * math.pi))
gain_YY = beams['YY'] / (beam_dOMEGA_sum_YY / (4.00 * math.pi))
ant_efficiency = 1.00
aeff_XX = (7161.97 / (freq_mhz * freq_mhz)) * (gain_XX * ant_efficiency)
aeff_YY = (7161.97 / (freq_mhz * freq_mhz)) * (gain_YY * ant_efficiency)
T_sys_XX = (Tant_XX + T_rcv)
T_sys_YY = (Tant_YY + T_rcv)
sens_XX = aeff_XX / T_sys_XX
sens_YY = aeff_YY / T_sys_YY
sefd_XX = (2760.00 / sens_XX) # 2k/(A/T)
sefd_YY = (2760.00 / sens_YY) # 2k/(A/T)
noise_XX = sefd_XX / math.sqrt(bandwidth * inttime * antnum * (antnum - 1))
noise_YY = sefd_YY / math.sqrt(bandwidth * inttime * antnum * (antnum - 1))
print "%.2f Hz :" % (freq)
lstring = "\t\tXX (%.2f MHz) : T_ant_XX = %.2f = (%.8f / %.8f) , beam(%.4f,%.4f)=%.8f , gain=%.8f , aeff=%.8f, "
lstring += "sensitivity (A/T) = %.20f -> SEFD_XX = %.2f Jy -> noise_XX = %.4f Jy"
params = (freq_mhz, Tant_XX, beamsky_sum_XX, beam_sum_XX, pointing_az_deg,
pointing_za_deg, beams['XX'], gain_XX, aeff_XX, sens_XX, sefd_XX,
noise_XX)
print lstring % params
lstring = "\t\tYY (%.2f MHz) : T_ant_YY = %.2f = (%.8f / %.8f) , beam(%.4f,%.4f)=%.8f , gain=%.8f , aeff=%.8f, "
lstring += "sensitivity (A/T) = %.20f -> SEFD_YY = %.2f Jy -> noise_YY = %.4f Jy"
params = (freq_mhz, Tant_YY, beamsky_sum_YY, beam_sum_YY, pointing_az_deg,
pointing_za_deg, beams['YY'], gain_YY, aeff_YY, sens_YY, sefd_YY,
noise_YY)
print lstring % params
print "Noise expected on XX images = %.4f Jy" % noise_XX
print "Noise expected on YY images = %.4f Jy" % noise_YY
return (aeff_XX, T_sys_XX, sens_XX, sefd_XX, noise_XX, aeff_YY, T_sys_YY,
sens_YY, sefd_YY, noise_YY)
def find_t_sys_gain(pulsar, obsid,
p_ra=None, p_dec=None,
dect_beg=None, dect_end=None,
obs_beg=None, obs_end=None,
common_metadata=None, full_metadata=None,
query=None, min_z_power=0.3, trcvr=data_load.TRCVR_FILE):
"""Finds the system temperature and gain for an observation.
Parameters
----------
pulsar : `str`
The Jname of the pulsar.
obsid : `int`
The MWA Observation ID.
p_ra, p_dec : `str`, optional
The target's right ascension and declination in sexidecimals. If not supplied will use the values from the ANTF.
dect_beg, dect_end : `int`, optional
The beg and end GPS time of the detection to calculate over.
If not supplied will estimate beam enter and exit.
obs_beg, obs_end : `int`, optional
Beginning and end GPS time of the observation.
If not supplied will use :py:meth:`vcstools.metadb_utils.obs_max_min` to find it.
common_metadata : `list`, optional
The list of common metadata generated from :py:meth:`vcstools.metadb_utils.get_common_obs_metadata`.
full_metadata : `dict`, optional
The dictionary of metadata generated from :py:meth:`vcstools.metadb_utils.getmeta`.
query : psrqpy object, optional
A previous psrqpy.QueryATNF query. Can be supplied to prevent performing a new query.
min_z_power : `float`, optional
Zenith normalised power cut off. |br| Default: 0.3.
trcvr : `str`
The location of the MWA receiver temp csv file. |br| Default: <vcstools_data_dir>MWA_Trcvr_tile_56.csv
Returns
-------
t_sys : `float`
The system temperature in K.
t_sys_err : `float`
The system temperature's uncertainty.
gain : `float`
The system gain in K/Jy.
gain_err : `float`
The gain's uncertainty.
"""
# get ra and dec if not supplied
if query is None:
logger.debug("Obtaining pulsar RA and Dec from ATNF")
query = psrqpy.QueryATNF(psrs=[pulsar], loadfromdb=data_load.ATNF_LOC).pandas
query_id = list(query['PSRJ']).index(pulsar)
if not p_ra or not p_dec:
p_ra = query["RAJ"][query_id]
p_dec= query["DECJ"][query_id]
# get metadata if not supplied
if not common_metadata:
logger.debug("Obtaining obs metadata")
common_metadata = get_common_obs_metadata(obsid)
obsid, obs_ra, obs_dec, _, delays, centrefreq, channels = common_metadata
if not dect_beg or not dect_end:
# Estimate integration time from when the source enters and exits the beam
dect_beg, dect_end = source_beam_coverage_and_times(obsid, pulsar,
p_ra=p_ra, p_dec=p_dec,
obs_beg=obs_beg, obs_end=obs_end,
min_z_power=min_z_power,
common_metadata=common_metadata,
query=query)[:2]
start_time = dect_end - int(obsid)
t_int = dect_end - dect_beg + 1
#Get important info
ntiles = 128 #TODO actually we excluded some tiles during beamforming, so we'll need to account for that here
beam_power = get_beam_power_over_time(np.array([[pulsar, p_ra, p_dec]]),
common_metadata=[obsid, obs_ra, obs_dec, t_int, delays,
centrefreq, channels],
dt=100, start_time=start_time)
mean_beam_power = np.mean(beam_power)
# Usa a primary beam function to convolve the sky temperature with the primary beam
# prints suppressed
sys.stdout = open(os.devnull, 'w')
_, _, Tsky_XX, _, _, _, Tsky_YY, _ = pbtant.make_primarybeammap(int(obsid), delays, centrefreq*1e6, 'analytic', plottype='None')
sys.stdout = sys.__stdout__
#TODO can be inaccurate for coherent but is too difficult to simulate
t_sky = (Tsky_XX + Tsky_YY) / 2.
# Get T_sys by adding Trec and Tsky (other temperatures are assumed to be negligible
t_sys_table = t_sky + get_Trec(centrefreq, trcvr_file=trcvr)
t_sys = np.mean(t_sys_table)
t_sys_err = t_sys*0.02 #TODO: figure out what t_sys error is
logger.debug("pul_ra: {} pul_dec: {}".format(p_ra, p_dec))
_, _, zas = mwa_alt_az_za(obsid, ra=p_ra, dec=p_dec)
theta = np.radians(zas)
gain = from_power_to_gain(mean_beam_power, centrefreq*1e6, ntiles, coh=True)
logger.debug("mean_beam_power: {} theta: {} pi: {}".format(mean_beam_power, theta, np.pi))
gain_err = gain * ((1. - mean_beam_power)*0.12 + 2.*(theta/(0.5*np.pi))**2. + 0.1)
return t_sys, t_sys_err, gain, gain_err
