git.gag.com Git - debian/gnuradio/blob - gnuradio-examples/python/digital/benchmark_loopback.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2005, 2006, 2007 Free Software Foundation, Inc.
   4 #
   5 # This file is part of GNU Radio
   6 #
   7 # GNU Radio is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 3, or (at your option)
  10 # any later version.
  11 #
  12 # GNU Radio is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with GNU Radio; see the file COPYING.  If not, write to
  19 # the Free Software Foundation, Inc., 51 Franklin Street,
  20 # Boston, MA 02110-1301, USA.
  21 #
  22
  23 from gnuradio import gr, gru, modulation_utils
  24 from gnuradio import eng_notation
  25 from gnuradio.eng_option import eng_option
  26 from optparse import OptionParser
  27
  28 import random, time, struct, sys, math
  29
  30 # from current dir
  31 from transmit_path_lb import transmit_path
  32 from receive_path_lb import receive_path
  33 import fusb_options
  34
  35 class awgn_channel(gr.hier_block2):
  36     def __init__(self, sample_rate, noise_voltage, frequency_offset, seed=False):
  37
  38         gr.hier_block2.__init__(self, "awgn_channel",
  39                                 gr.io_signature(1, 1, gr.sizeof_gr_complex), # Input signature
  40                                 gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
  41
  42         # Create the Gaussian noise source
  43         if not seed:
  44             self.noise = gr.noise_source_c(gr.GR_GAUSSIAN, noise_voltage)
  45         else:
  46             rseed = int(time.time())
  47             self.noise = gr.noise_source_c(gr.GR_GAUSSIAN, noise_voltage, rseed)
  48
  49         self.adder =  gr.add_cc()
  50
  51         # Create the frequency offset
  52         self.offset = gr.sig_source_c(1, gr.GR_SIN_WAVE,
  53                                       frequency_offset, 1.0, 0.0)
  54         self.mixer = gr.multiply_cc()
  55
  56         # Connect the components
  57         self.connect(self, (self.mixer, 0))
  58         self.connect(self.offset, (self.mixer, 1))
  59         self.connect(self.mixer, (self.adder, 0))
  60         self.connect(self.noise, (self.adder, 1))
  61         self.connect(self.adder, self)
  62
  63 class my_top_block(gr.top_block):
  64     def __init__(self, mod_class, demod_class, rx_callback, options):
  65         gr.top_block.__init__(self)
  66
  67         channelon = True;
  68
  69         SNR = 10.0**(options.snr/10.0)
  70         frequency_offset = options.frequency_offset
  71
  72         power_in_signal = abs(options.tx_amplitude)**2
  73         noise_power = power_in_signal/SNR
  74         noise_voltage = math.sqrt(noise_power)
  75
  76         self.txpath = transmit_path(mod_class, options)
  77         self.throttle = gr.throttle(gr.sizeof_gr_complex, options.sample_rate)
  78         self.rxpath = receive_path(demod_class, rx_callback, options)
  79
  80         if channelon:
  81             self.channel = awgn_channel(options.sample_rate, noise_voltage,
  82                                         frequency_offset, options.seed)
  83
  84             if options.discontinuous:
  85                 z = 20000*[0,]
  86                 self.zeros = gr.vector_source_c(z, True)
  87                 packet_size = 5*((4+8+4+1500+4) * 8)
  88                 self.mux = gr.stream_mux(gr.sizeof_gr_complex, [packet_size-0, int(9e5)])
  89
  90                 # Connect components
  91                 self.connect(self.txpath, (self.mux,0))
  92                 self.connect(self.zeros, (self.mux,1))
  93                 self.connect(self.mux, self.channel, self.rxpath)
  94
  95             else:
  96                 self.connect(self.txpath, self.channel, self.rxpath)
  97
  98         else:
  99             # Connect components
 100             self.connect(self.txpath, self.throttle, self.rxpath)
 101
 102
 103 # /////////////////////////////////////////////////////////////////////////////
 104 #                                   main
 105 # /////////////////////////////////////////////////////////////////////////////
 106
 107 def main():
 108
 109     global n_rcvd, n_right
 110
 111     n_rcvd = 0
 112     n_right = 0
 113
 114     def rx_callback(ok, payload):
 115         global n_rcvd, n_right
 116         (pktno,) = struct.unpack('!H', payload[0:2])
 117         n_rcvd += 1
 118         if ok:
 119             n_right += 1
 120
 121         print "ok = %5s  pktno = %4d  n_rcvd = %4d  n_right = %4d" % (
 122             ok, pktno, n_rcvd, n_right)
 123         # print payload[2:len(payload)]
 124
 125     def send_pkt(payload='', eof=False):
 126         return tb.txpath.send_pkt(payload, eof)
 127
 128
 129     mods = modulation_utils.type_1_mods()
 130     demods = modulation_utils.type_1_demods()
 131
 132     parser = OptionParser(option_class=eng_option, conflict_handler="resolve")
 133     expert_grp = parser.add_option_group("Expert")
 134     channel_grp = parser.add_option_group("Channel")
 135
 136     parser.add_option("-m", "--modulation", type="choice", choices=mods.keys(),
 137                       default='dbpsk',
 138                       help="Select modulation from: %s [default=%%default]"
 139                             % (', '.join(mods.keys()),))
 140
 141     parser.add_option("-s", "--size", type="eng_float", default=1500,
 142                       help="set packet size [default=%default]")
 143     parser.add_option("-M", "--megabytes", type="eng_float", default=1.0,
 144                       help="set megabytes to transmit [default=%default]")
 145     parser.add_option("","--discontinuous", action="store_true", default=False,
 146                       help="enable discontinous transmission (bursts of 5 packets)")
 147
 148     channel_grp.add_option("", "--sample-rate", type="eng_float", default=1e5,
 149                            help="set speed of channel/simulation rate to RATE [default=%default]")
 150     channel_grp.add_option("", "--snr", type="eng_float", default=30,
 151                            help="set the SNR of the channel in dB [default=%default]")
 152     channel_grp.add_option("", "--frequency-offset", type="eng_float", default=0,
 153                            help="set frequency offset introduced by channel [default=%default]")
 154     channel_grp.add_option("", "--seed", action="store_true", default=False,
 155                            help="use a random seed for AWGN noise [default=%default]")
 156
 157     transmit_path.add_options(parser, expert_grp)
 158     receive_path.add_options(parser, expert_grp)
 159
 160     for mod in mods.values():
 161         mod.add_options(expert_grp)
 162     for demod in demods.values():
 163         demod.add_options(expert_grp)
 164
 165     (options, args) = parser.parse_args ()
 166
 167     if len(args) != 0:
 168         parser.print_help()
 169         sys.exit(1)
 170
 171     r = gr.enable_realtime_scheduling()
 172     if r != gr.RT_OK:
 173         print "Warning: failed to enable realtime scheduling"
 174
 175     # Create an instance of a hierarchical block
 176     tb = my_top_block(mods[options.modulation], demods[options.modulation], rx_callback, options)
 177     tb.start()
 178
 179     # generate and send packets
 180     nbytes = int(1e6 * options.megabytes)
 181     n = 0
 182     pktno = 0
 183     pkt_size = int(options.size)
 184
 185     while n < nbytes:
 186         send_pkt(struct.pack('!H', pktno) + (pkt_size - 2) * chr(pktno & 0xff))
 187         n += pkt_size
 188         pktno += 1
 189
 190     send_pkt(eof=True)
 191
 192     tb.wait()
 193
 194 if __name__ == '__main__':
 195     try:
 196         main()
 197     except KeyboardInterrupt:
 198         pass