add rtl_modes.py for rtl-sdr

Needs librtlsdr and gr-osmosdr to be installed.
See http://sdr.osmocom.org/trac/wiki/rtl-sdr for
details.

Signed-off-by: Steve Markgraf <steve@steve-m.de>

src/python/rtl_modes.py

@@ -0,0 +1,200 @@
+#!/usr/bin/env python
+# Copyright 2010 Nick Foster
+# 
+# This file is part of gr-air-modes
+# 
+# gr-air-modes 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 3, or (at your option)
+# any later version.
+# 
+# gr-air-modes 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 gr-air-modes; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+# Important: change that to your rough position.
+my_position = [37.76225, -122.44254]
+
+from gnuradio import gr, gru, optfir, eng_notation, blks2, air
+from gnuradio.eng_option import eng_option
+from osmosdr import *
+from optparse import OptionParser
+import time, os, sys, threading
+from string import split, join
+from modes_print import modes_output_print
+from modes_sql import modes_output_sql
+from modes_sbs1 import modes_output_sbs1
+from modes_kml import modes_kml
+from modes_raw_server import modes_raw_server
+import gnuradio.gr.gr_threading as _threading
+import csv
+
+class top_block_runner(_threading.Thread):
+    def __init__(self, tb):
+        _threading.Thread.__init__(self)
+        self.setDaemon(1)
+        self.tb = tb
+        self.done = False
+        self.start()
+
+    def run(self):
+        self.tb.run()
+        self.done = True
+
+class adsb_rx_block (gr.top_block):
+  def __init__(self, options, args, queue):
+    gr.top_block.__init__(self)
+
+    self.options = options
+    self.args = args
+    rate = int(options.rate)
+    rtl_rate = 2.4e6;
+
+    if options.filename is None:
+      # example for rtl_tcp
+      #self.u = source_c(args="nchan=" + str(1) + " " + "rtl_tcp=127.0.0.1:1234")
+      self.u = source_c()
+
+      self.u.set_sample_rate(rtl_rate)
+
+      if not(self.u.set_center_freq(options.freq)):
+        print "Failed to set initial frequency"
+
+      # enable manual gain
+      self.u.set_gain_mode(0)
+
+      print "Setting gain to %i" % (options.gain,)
+      self.u.set_gain(options.gain)
+      print "Gain is %i" % (self.u.get_gain(),)
+
+    else:
+      self.u = gr.file_source(gr.sizeof_gr_complex, options.filename)
+
+    print "Rate is %i" % (rate,)
+
+    pass_all = 0
+    if options.output_all :
+      pass_all = 1
+
+    self.demod = gr.complex_to_mag()
+    self.avg = gr.moving_average_ff(100, 1.0/100, 400)
+    
+    #the DBSRX especially tends to be spur-prone; the LPF keeps out the
+    #spur multiple that shows up at 2MHz
+    self.lpfiltcoeffs = gr.firdes.low_pass(1, 5 * rtl_rate, 1.2e6, 300e3)
+    self.resamp = blks2.rational_resampler_ccf(interpolation=5, decimation=3, taps=self.lpfiltcoeffs)
+
+    self.preamble = air.modes_preamble(rate, options.threshold)
+    #self.framer = air.modes_framer(rate)
+    self.slicer = air.modes_slicer(rate, queue)
+
+    self.connect(self.u, self.resamp, self.demod)
+    self.connect(self.demod, self.avg)
+    self.connect(self.demod, (self.preamble, 0))
+    self.connect(self.avg, (self.preamble, 1))
+    self.connect((self.preamble, 0), (self.slicer, 0))
+
+  def tune(self, freq):
+    result = self.u.set_center_freq(freq, 0)
+    return result
+
+def printraw(msg):
+    print msg
+
+if __name__ == '__main__':
+  usage = "%prog: [options] output filename"
+  parser = OptionParser(option_class=eng_option, usage=usage)
+  parser.add_option("-R", "--rx-subdev-spec", type="string",
+          help="select USRP Rx side A or B", metavar="SUBDEV")
+  parser.add_option("-A", "--antenna", type="string",
+          help="select which antenna to use on daughterboard")
+  parser.add_option("-f", "--freq", type="eng_float", default=1090e6,
+                      help="set receive frequency in Hz [default=%default]", metavar="FREQ")
+  parser.add_option("-g", "--gain", type="eng_float", default=49.0,
+                      help="set RF gain", metavar="dB")
+  parser.add_option("-r", "--rate", type="eng_float", default=4000000,
+                      help="set ADC sample rate [default=%default]")
+  parser.add_option("-T", "--threshold", type="eng_float", default=3.0,
+                      help="set pulse detection threshold above noise in dB [default=%default]")
+  parser.add_option("-a","--output-all", action="store_true", default=False,
+                      help="output all frames")
+  parser.add_option("-F","--filename", type="string", default=None,
+            help="read data from file instead of USRP")
+  parser.add_option("-K","--kml", type="string", default=None,
+                      help="filename for Google Earth KML output")
+  parser.add_option("-P","--sbs1", action="store_true", default=False,
+                      help="open an SBS-1-compatible server on port 30003")
+  parser.add_option("-w","--raw", action="store_true", default=False,
+                      help="open a server outputting raw timestamped data on port 9988")
+  parser.add_option("-n","--no-print", action="store_true", default=False,
+                      help="disable printing decoded packets to stdout")
+  parser.add_option("-l","--location", type="string", default=None,
+                      help="GPS coordinates of receiving station in format xx.xxxxx,xx.xxxxx")
+  (options, args) = parser.parse_args()
+
+  if options.location is not None:
+    reader = csv.reader([options.location], quoting=csv.QUOTE_NONNUMERIC)
+    my_position = reader.next()
+
+  queue = gr.msg_queue()
+  
+  outputs = [] #registry of plugin output functions
+  updates = [] #registry of plugin update functions
+
+  if options.kml is not None:
+    sqlport = modes_output_sql(my_position, 'adsb.db') #create a SQL parser to push stuff into SQLite
+    outputs.append(sqlport.insert)
+    #also we spawn a thread to run every 30 seconds (or whatever) to generate KML
+    kmlgen = modes_kml('adsb.db', options.kml, my_position) #create a KML generating thread which reads the database
+
+  if options.sbs1 is True:
+    sbs1port = modes_output_sbs1(my_position)
+    outputs.append(sbs1port.output)
+    updates.append(sbs1port.add_pending_conns)
+    
+  if options.no_print is not True:
+    outputs.append(modes_output_print(my_position).parse)
+
+  if options.raw is True:
+    rawport = modes_raw_server()
+    outputs.append(rawport.output)
+    outputs.append(printraw)
+    updates.append(rawport.add_pending_conns)
+
+  fg = adsb_rx_block(options, args, queue)
+  runner = top_block_runner(fg)
+
+  while 1:
+    try:
+      #the update registry is really for the SBS1 and raw server plugins -- we're looking for new TCP connections.
+      #i think we have to do this here rather than in the output handler because otherwise connections will stack up
+      #until the next output arrives
+      for update in updates:
+        update()
+      
+      #main message handler
+      if queue.empty_p() == 0 :
+        while queue.empty_p() == 0 :
+          msg = queue.delete_head() #blocking read
+
+          for out in outputs:
+            out(msg.to_string())
+
+      elif runner.done:
+        raise KeyboardInterrupt
+      else:
+        time.sleep(0.1)
+
+    except KeyboardInterrupt:
+      fg.stop()
+      runner = None
+      if options.kml is not None:
+          kmlgen.done = True
+      break