#!/usr/bin/env python## Copyright 2006, 2007 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 3, 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.# from gnuradio import gr, blks2from gnuradio import eng_notationfrom gnuradio.eng_option import eng_optionfrom optparse import OptionParserimport random, time, struct, sys, math, os# from current dirfrom transmit_path import transmit_pathfrom receive_path import receive_pathclass my_top_block(gr.top_block):    def __init__(self, callback, options):        gr.top_block.__init__(self)        if not options.channel_off:            SNR = 10.0**(options.snr/10.0)            power_in_signal = abs(options.tx_amplitude)**2.0            noise_power_in_channel = power_in_signal/SNR            noise_voltage = math.sqrt(noise_power_in_channel/2.0)            print "Noise voltage: ", noise_voltage            frequency_offset = options.frequency_offset / options.fft_length            print "Frequency offset: ", frequency_offset            if options.multipath_on:                taps = [1.0, .2, 0.0, .1, .08, -.4, .12, -.2, 0, 0, 0, .3]            else:                taps = [1.0, 0.0]        else:            noise_voltage = 0.0            frequency_offset = 0.0            taps = [1.0, 0.0]        symbols_per_packet = math.ceil(((4+options.size+4) * 8) / options.occupied_tones)        samples_per_packet = (symbols_per_packet+2) * (options.fft_length+options.cp_length)        print "Symbols per Packet: ", symbols_per_packet        print "Samples per Packet: ", samples_per_packet        if options.discontinuous:            stream_size = [100000, int(options.discontinuous*samples_per_packet)]        else:            stream_size = [0, 100000]        z = [0,]        self.zeros = gr.vector_source_c(z, True)        self.txpath = transmit_path(options)        #self.mux = gr.stream_mux(gr.sizeof_gr_complex, stream_size)        self.throttle = gr.throttle(gr.sizeof_gr_complex, options.sample_rate)        self.channel = blks2.channel_model(noise_voltage, frequency_offset,                                           options.clockrate_ratio, taps)        self.rxpath = receive_path(callback, options)                        #self.connect(self.zeros, (self.mux,0))        #self.connect(self.txpath, (self.mux,1))        #self.connect(self.mux, self.throttle, self.channel, self.rxpath)        #self.connect(self.mux, self.throttle, self.rxpath)        self.connect(self.txpath, self.throttle, self.channel, self.rxpath)                if options.log:            self.connect(self.txpath, gr.file_sink(gr.sizeof_gr_complex, "txpath.dat"))            #self.connect(self.mux, gr.file_sink(gr.sizeof_gr_complex, "mux.dat"))            #self.connect(self.channel, gr.file_sink(gr.sizeof_gr_complex, "channel.dat"))            # /////////////////////////////////////////////////////////////////////////////#                                   main# /////////////////////////////////////////////////////////////////////////////def main():    global n_rcvd, n_right            n_rcvd = 0    n_right = 0            def send_pkt(payload='', eof=False):        return tb.txpath.send_pkt(payload, eof)            def rx_callback(ok, payload):        global n_rcvd, n_right        n_rcvd += 1        (pktno,) = struct.unpack('!H', payload[0:2])        if ok:            n_right += 1        print "ok: %r \t pktno: %d \t n_rcvd: %d \t n_right: %d" % (ok, pktno, n_rcvd, n_right)        printlst = list()        for x in payload[2:]:            t = hex(ord(x)).replace('0x', '')            if(len(t) == 1):                t = '0' + t            printlst.append(t)        printable = ''.join(printlst)        print printable        print "\n"                    parser = OptionParser(option_class=eng_option, conflict_handler="resolve")    expert_grp = parser.add_option_group("Expert")    parser.add_option("-s", "--size", type="eng_float", default=400,                      help="set packet size [default=%default]")    parser.add_option("-M", "--megabytes", type="eng_float", default=1.0,                      help="set megabytes to transmit [default=%default]")    parser.add_option("-r", "--sample-rate", type="eng_float", default=1e5,                      help="limit sample rate to RATE in throttle (%default)")     parser.add_option("", "--snr", type="eng_float", default=30,                      help="set the SNR of the channel in dB [default=%default]")    parser.add_option("", "--frequency-offset", type="eng_float", default=0,                      help="set frequency offset introduced by channel [default=%default]")    parser.add_option("", "--clockrate-ratio", type="eng_float", default=1.0,                      help="set clock rate ratio (sample rate difference) between two systems [default=%default]")    parser.add_option("","--discontinuous", type="int", default=0,                      help="enable discontinous transmission, burst of N packets [Default is continuous]")    parser.add_option("","--channel-off", action="store_true", default=False,                      help="Turns AWGN, freq offset channel off")    parser.add_option("","--multipath-on", action="store_true", default=False,                      help="enable multipath")    transmit_path.add_options(parser, expert_grp)    receive_path.add_options(parser, expert_grp)    blks2.ofdm_mod.add_options(parser, expert_grp)    blks2.ofdm_demod.add_options(parser, expert_grp)        (options, args) = parser.parse_args ()           # build the graph    tb = my_top_block(rx_callback, options)        r = gr.enable_realtime_scheduling()    #    if r != gr.RT_OK:    #        print "Warning: failed to enable realtime scheduling"        tb.start()                       # start flow graph        # generate and send packets    nbytes = int(1e6 * options.megabytes)    n = 0    pktno = 0    pkt_size = int(options.size)    while n < nbytes:        #r = ''.join([chr(random.randint(0,255)) for i in range(pkt_size-2)])        #pkt_contents = struct.pack('!H', pktno) + r        pkt_contents = struct.pack('!H', pktno) + (pkt_size - 2) * chr(pktno & 0xff)        send_pkt(pkt_contents)        n += pkt_size        #sys.stderr.write('.')        #if options.discontinuous and pktno % 5 == 4:        #    time.sleep(1)        pktno += 1            send_pkt(eof=True)    tb.wait()                       # wait for it to finishif __name__ == '__main__':    try:        main()    except KeyboardInterrupt:        pass