#!/usr/bin/env python # # Copyright 2003,2004,2005 Free Software Foundation, Inc. # # This file is part of GNU Radio # # GNU Radio is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2, or (at your option) # any later version. # # GNU Radio is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with GNU Radio; see the file COPYING. If not, write to # the Free Software Foundation, Inc., 51 Franklin Street, # Boston, MA 02110-1301, USA. # import Numeric import math import ephem import time # # Simple class for allowing local definition of a calibration function # for raw samples coming from the RA detector chain. Each observatory # is different, and rather than hacking up the main code in usrp_ra_receiver # we define the appropriate function here. # # For example, one could calibrate the output in Janskys, rather than # dB. # # def calib_default_total_power(data): r = 10.0*math.log10(data) return(r) def calib_numogate_ridge_observatory_total_power(data): me = ephem.Observer() # # PyEphem wants lat/long as strings, rather than floats--took me quite # a long time to figure that out. If they don't arrive as strings, # the calculations for sidereal time are complete garbage # me.long = str(-76.043) me.lat = str(44.967) me.date = ephem.now() sidtime = me.sidereal_time() foo = time.localtime() if not "calib_prefix" in globals(): pfx = "./" else: pfx = globals()["calib_prefix"] filenamestr = "%s/%04d%02d%02d%02d" % (pfx, foo.tm_year, foo.tm_mon, foo.tm_mday, foo.tm_hour) rainbow_file = open (filenamestr+".tpdat","a") r = (data / 409.6) flt = "%6.3f" % r #r = calib_default_total_power(data) inter = globals()["calib_decln"] rainbow_file.write(str(ephem.hours(sidtime))+" "+flt+" "+str(inter)+"\n") rainbow_file.close() return(r) def calib_numogate_ridge_observatory_fft(data,l): me = ephem.Observer() # # PyEphem wants lat/long as strings, rather than floats--took me quite # a long time to figure that out. If they don't arrive as strings, # the calculations for sidereal time are complete garbage # me.long = str(-76.043) me.lat = str(44.967) me.date = ephem.now() sidtime = me.sidereal_time() foo = time.localtime() if not "calib_prefix" in globals(): pfx = "./" else: pfx = globals()["calib_prefix"] filenamestr = "%s/%04d%02d%02d%02d" % (pfx, foo.tm_year, foo.tm_mon, foo.tm_mday, foo.tm_hour) now = time.time() if not "calib_then" in globals(): globals()["calib_then"] = now delta = (l/1024)*5 if (now - globals()["calib_then"]) >= delta: globals()["calib_then"] = now rainbow_file = open (filenamestr+".sdat","a") r = calib_default_fft(data,l) inter = globals()["calib_decln"] rainbow_file.write("data:"+str(ephem.hours(sidtime))+" "+str(inter)+" "+str(r)+"\n") rainbow_file.close() return(r) return(data) def calib_default_fft(db,l): return(db) # # We capture various parameters from the receive chain here, because # they can affect the calibration equations. # # def calib_set_gain(gain): globals()["calib_gain_setting"] = gain def calib_set_integ(integ): globals()["calib_integ_setting"] = integ def calib_set_bw(bw): globals()["calib_bw_setting"] = bw def calib_set_freq(freq): globals()["calib_freq_setting"] = freq def calib_set_avg_alpha(alpha): globals()["calib_avg_alpha"] = alpha def calib_set_interesting(inter): globals()["calib_is_interesting"] = inter def calib_set_decln(dec): globals()["calib_decln"] = dec def calib_set_prefix(pfx): globals()["calib_prefix"] = pfx