3 # Copyright 2005, 2006, 2007 Free Software Foundation, Inc.
5 # This file is part of GNU Radio
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 2, or (at your option)
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.
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.
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
28 import random, time, struct, sys, math
31 from transmit_path_lb import transmit_path
32 from receive_path_lb import receive_path
35 class awgn_channel(gr.hier_block):
36 def __init__(self, fg, sample_rate, noise_voltage, frequency_offset, seed=False):
37 self.input = gr.add_const_cc(0) # dummy input device
39 # Create the Gaussian noise source
41 self.noise = gr.noise_source_c(gr.GR_GAUSSIAN, noise_voltage)
43 rseed = int(time.time())
44 self.noise = gr.noise_source_c(gr.GR_GAUSSIAN, noise_voltage, rseed)
46 self.adder = gr.add_cc()
48 # Create the frequency offset
49 self.offset = gr.sig_source_c(1, gr.GR_SIN_WAVE,
50 frequency_offset, 1.0, 0.0)
51 self.mixer = gr.multiply_cc()
53 # Connect the components
54 fg.connect(self.input, (self.mixer, 0))
55 fg.connect(self.offset, (self.mixer, 1))
56 fg.connect(self.mixer, (self.adder, 0))
57 fg.connect(self.noise, (self.adder, 1))
59 gr.hier_block.__init__(self, fg, self.input, self.adder)
61 class my_graph(gr.flow_graph):
62 def __init__(self, mod_class, demod_class, rx_callback, options):
63 gr.flow_graph.__init__(self)
67 SNR = 10.0**(options.snr/10.0)
68 frequency_offset = options.frequency_offset
70 power_in_signal = abs(options.tx_amplitude)**2
71 noise_power = power_in_signal/SNR
72 noise_voltage = math.sqrt(noise_power)
74 self.txpath = transmit_path(self, mod_class, options)
75 self.throttle = gr.throttle(gr.sizeof_gr_complex, options.sample_rate)
76 self.rxpath = receive_path(self, demod_class, rx_callback, options)
79 self.channel = awgn_channel(self, options.sample_rate, noise_voltage,
80 frequency_offset, options.seed)
82 if options.discontinuous:
84 self.zeros = gr.vector_source_c(z, True)
85 packet_size = 5*((4+8+4+1500+4) * 8)
86 self.mux = gr.stream_mux(gr.sizeof_gr_complex, [packet_size-0, int(9e5)])
89 self.connect(self.txpath, (self.mux,0))
90 self.connect(self.zeros, (self.mux,1))
91 self.connect(self.mux, self.channel, self.rxpath)
94 self.connect(self.txpath, self.channel, self.rxpath)
98 self.connect(self.txpath, self.throttle, self.rxpath)
101 # /////////////////////////////////////////////////////////////////////////////
103 # /////////////////////////////////////////////////////////////////////////////
107 global n_rcvd, n_right
112 def rx_callback(ok, payload):
113 global n_rcvd, n_right
114 (pktno,) = struct.unpack('!H', payload[0:2])
119 print "ok = %5s pktno = %4d n_rcvd = %4d n_right = %4d" % (
120 ok, pktno, n_rcvd, n_right)
121 # print payload[2:len(payload)]
123 def send_pkt(payload='', eof=False):
124 return fg.txpath.send_pkt(payload, eof)
127 mods = modulation_utils.type_1_mods()
128 demods = modulation_utils.type_1_demods()
130 parser = OptionParser(option_class=eng_option, conflict_handler="resolve")
131 expert_grp = parser.add_option_group("Expert")
132 channel_grp = parser.add_option_group("Channel")
134 parser.add_option("-m", "--modulation", type="choice", choices=mods.keys(),
136 help="Select modulation from: %s [default=%%default]"
137 % (', '.join(mods.keys()),))
139 parser.add_option("-s", "--size", type="eng_float", default=1500,
140 help="set packet size [default=%default]")
141 parser.add_option("-M", "--megabytes", type="eng_float", default=1.0,
142 help="set megabytes to transmit [default=%default]")
143 parser.add_option("","--discontinuous", action="store_true", default=False,
144 help="enable discontinous transmission (bursts of 5 packets)")
146 channel_grp.add_option("", "--sample-rate", type="eng_float", default=1e5,
147 help="set speed of channel/simulation rate to RATE [default=%default]")
148 channel_grp.add_option("", "--snr", type="eng_float", default=30,
149 help="set the SNR of the channel in dB [default=%default]")
150 channel_grp.add_option("", "--frequency-offset", type="eng_float", default=0,
151 help="set frequency offset introduced by channel [default=%default]")
152 channel_grp.add_option("", "--seed", action="store_true", default=False,
153 help="use a random seed for AWGN noise [default=%default]")
155 transmit_path.add_options(parser, expert_grp)
156 receive_path.add_options(parser, expert_grp)
158 for mod in mods.values():
159 mod.add_options(expert_grp)
160 for demod in demods.values():
161 demod.add_options(expert_grp)
163 (options, args) = parser.parse_args ()
169 r = gr.enable_realtime_scheduling()
171 print "Warning: failed to enable realtime scheduling"
173 # Create an instance of a hierarchical block
174 fg = my_graph(mods[options.modulation], demods[options.modulation], rx_callback, options)
177 # generate and send packets
178 nbytes = int(1e6 * options.megabytes)
181 pkt_size = int(options.size)
184 send_pkt(struct.pack('!H', pktno) + (pkt_size - 2) * chr(pktno & 0xff))
192 if __name__ == '__main__':
195 except KeyboardInterrupt: