| 1 | #!/usr/bin/env python |
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| 2 | # |
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| 3 | # Copyright 2005,2006,2007,2009 Free Software Foundation, Inc. |
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| 4 | # |
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| 5 | # Copyright 2009 Virginia Polytechnic Institute and State University |
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| 6 | # |
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| 7 | # GNU Radio is free software; you can redistribute it and/or modify |
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| 8 | # it under the terms of the GNU General Public License as published by |
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| 9 | # the Free Software Foundation; either version 3, or (at your option) |
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| 10 | # any later version. |
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| 11 | # |
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| 12 | # GNU Radio is distributed in the hope that it will be useful, |
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| 13 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 14 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 15 | # GNU General Public License for more details. |
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| 16 | # |
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| 17 | # You should have received a copy of the GNU General Public License |
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| 18 | # along with GNU Radio; see the file COPYING. If not, write to |
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| 19 | # the Free Software Foundation, Inc., 51 Franklin Street, |
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| 20 | # Boston, MA 02110-1301, USA. |
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| 21 | # |
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| 22 | |
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| 23 | from gnuradio import gr, gru, modulation_utils |
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| 24 | from gnuradio import eng_notation |
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| 25 | from gnuradio.eng_option import eng_option |
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| 26 | from optparse import OptionParser |
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| 27 | from numpy import random |
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| 28 | import random, time, struct, sys, math |
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| 29 | from datetime import datetime |
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| 30 | |
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| 31 | # from current dir |
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| 32 | #from transmit_path import transmit_path |
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| 33 | #from receive_path import receive_path |
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| 34 | |
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| 35 | import usrp_transmit_path |
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| 36 | import usrp_receive_path |
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| 37 | |
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| 38 | |
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| 39 | try: |
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| 40 | from cross import * |
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| 41 | cross_import = True |
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| 42 | except ImportError: |
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| 43 | cross_import = False |
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| 44 | |
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| 45 | global sync_status,mode,ch,traffic_flag,n_rcvd, n_right |
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| 46 | global ticker_start,time_right_now #measuring duration over which no packet is sent |
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| 47 | ticker_start = datetime.now() |
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| 48 | #no_packet_stop_time = False |
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| 49 | global no_packet_period #allowed duration for no packet |
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| 50 | no_packet_period = 3 |
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| 51 | sync_status = False |
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| 52 | |
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| 53 | #Defining modes of operation |
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| 54 | # sync: the two nodes are trying to rendezvous on a common channel |
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| 55 | # traffic: the two node are communicating information to each other |
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| 56 | mode = "sync" #Default mode is sync |
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| 57 | traffic_flag = False |
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| 58 | |
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| 59 | class my_top_block(gr.top_block): |
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| 60 | |
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| 61 | def __init__(self, mod_class, demod_class, |
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| 62 | rx_callback, options_tx,options_rx): |
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| 63 | |
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| 64 | gr.top_block.__init__(self) |
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| 65 | self.rxpath = usrp_receive_path.usrp_receive_path(demod_class, rx_callback, options_rx) |
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| 66 | self.txpath = usrp_transmit_path.usrp_transmit_path(mod_class, options_tx) |
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| 67 | self.connect(self.txpath); |
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| 68 | self.connect(self.rxpath); |
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| 69 | |
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| 70 | |
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| 71 | def main(): |
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| 72 | |
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| 73 | global stats_array, count_array, time_array, n_rcvd |
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| 74 | global n_right, sync_status, mode, ch, traffic_flag |
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| 75 | global n_attempts, return_flag, crossShellHost, crossShellPort |
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| 76 | global ticker_start,time_right_now,no_packet_period |
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| 77 | |
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| 78 | |
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| 79 | n_rcvd = 0 |
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| 80 | n_right = 0 |
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| 81 | n_attempts = 5 |
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| 82 | return_flag = 0 |
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| 83 | |
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| 84 | count_array = [ 0, 0, 0, 0, 0] |
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| 85 | time_array = [ 0, 0, 0, 0, 0] |
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| 86 | stats_array = [ 0, 0, 0, 0, 0] |
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| 87 | |
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| 88 | |
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| 89 | def send_pkt(self, payload='', eof=False): |
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| 90 | return self.txpath.send_pkt(payload, eof) |
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| 91 | |
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| 92 | |
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| 93 | def get_real_channel(channel): |
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| 94 | |
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| 95 | real_channel = 1; |
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| 96 | |
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| 97 | get_channel = { |
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| 98 | 1: 1, |
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| 99 | 2: 7, |
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| 100 | 3: 8, |
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| 101 | 4: 14 |
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| 102 | } |
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| 103 | |
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| 104 | real_channel = get_channel[channel] |
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| 105 | |
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| 106 | return real_channel |
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| 107 | |
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| 108 | |
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| 109 | def get_average_time(channel,absent_time): |
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| 110 | |
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| 111 | global count_array, time_array |
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| 112 | |
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| 113 | count_array[channel] = count_array[channel] + 1 |
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| 114 | average_time = (time_array[channel] + absent_time) / count_array[channel] |
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| 115 | |
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| 116 | return average_time |
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| 117 | |
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| 118 | |
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| 119 | def get_freq(hop_freq,probe_level,absent_time,cross): |
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| 120 | |
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| 121 | # Convert hop_freq to our unique channel list |
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| 122 | |
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| 123 | if cross == True: |
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| 124 | |
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| 125 | freq_channel = { |
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| 126 | 462562500: 1, |
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| 127 | 462712500: 2, |
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| 128 | 467562500: 3, |
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| 129 | 467712500: 4, |
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| 130 | } |
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| 131 | |
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| 132 | currentParameters = Parameter(1) |
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| 133 | currentParameters[0].name = "channel" |
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| 134 | currentParameters[0].value = freq_channel[hop_freq] |
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| 135 | |
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| 136 | o = Observable(2) |
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| 137 | o[0].value = probe_level |
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| 138 | o[0].name = "energy" |
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| 139 | |
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| 140 | o[1].value = absent_time |
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| 141 | o[1].name = "communication_time" |
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| 142 | |
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| 143 | # If time == 0 then we are scanning and we dont want to |
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| 144 | # use this time in the averaging process. |
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| 145 | if absent_time != 0: |
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| 146 | try: |
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| 147 | UpdateParameterPerformance(currentParameters,1,o,1) |
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| 148 | except: |
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| 149 | print "fail" |
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| 150 | else: |
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| 151 | # Get the average communication time |
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| 152 | average_time = get_average_time(freq_channel[hop_freq], absent_time) |
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| 153 | o[1].value = average_time |
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| 154 | o[1].name = "communication_time" |
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| 155 | try: |
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| 156 | UpdateParameterPerformance(currentParameters,1,o,2) |
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| 157 | except: |
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| 158 | print "fail" |
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| 159 | |
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| 160 | p = Parameter(1) |
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| 161 | p = GetOptimalParameters(o,2,currentParameters,1); |
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| 162 | |
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| 163 | channel = get_real_channel(int(p[0].value)) |
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| 164 | else: |
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| 165 | channel = int(random.choice([1,7,8,14])) |
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| 166 | |
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| 167 | if channel < 8: |
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| 168 | hop_freq = float(1e6 * (462.5625+(channel-1)*0.025))#setting the centre freq frequency for sending packets |
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| 169 | else: |
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| 170 | hop_freq = float(1e6 * (467.5625+(channel-8)*0.025))#setting the centre freq frequency for sending packets |
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| 171 | |
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| 172 | return channel,hop_freq #returning the channel number and hop frequency |
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| 173 | |
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| 174 | |
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| 175 | def rx_callback(ok, payload): |
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| 176 | |
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| 177 | global n_rcvd, n_right,sync_status,mode,ch,traffic_flag,ticker_start |
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| 178 | |
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| 179 | ticker_start = datetime.now() |
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| 180 | #print "inside callback" |
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| 181 | #print "ticker_start ",ticker_start |
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| 182 | ########################## sync #################################### |
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| 183 | if mode == "sync": |
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| 184 | if ok: |
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| 185 | (pktno,) = struct.unpack('!H', payload[0:2]) |
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| 186 | (sync_signal,) = struct.unpack('!s', payload[2]) |
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| 187 | (data_channel,) = struct.unpack('!H', payload[3:5]) |
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| 188 | |
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| 189 | if str(sync_signal) == 'o' and str(data_channel) == str(ch): |
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| 190 | sync_status = True |
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| 191 | #tb.stop() |
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| 192 | |
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| 193 | if str(sync_signal) == 's' and str(data_channel) == str(ch): |
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| 194 | sync_status = True |
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| 195 | data = 'o' |
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| 196 | pktno=0 |
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| 197 | ack_payload = struct.pack('!HsH', pktno & 0xffff,data,ch & 0xffff) #+ data |
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| 198 | send_pkt(tb,ack_payload) #sending back the acknowledgement |
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| 199 | ################################################################### |
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| 200 | |
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| 201 | ######################### traffic ################################# |
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| 202 | if mode == "traffic": |
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| 203 | |
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| 204 | |
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| 205 | |
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| 206 | |
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| 207 | if ok: |
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| 208 | (data_header,) = struct.unpack('!s', payload[0]) |
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| 209 | if data_header == 'd': |
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| 210 | traffic_flag = True |
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| 211 | comm = struct.unpack('!14s', payload[1:15]) |
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| 212 | data = 'dI am fine.....' #Sending this message |
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| 213 | payload = struct.pack('!15s', data) |
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| 214 | send_pkt(tb,payload) |
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| 215 | |
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| 216 | ############################################################## |
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| 217 | |
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| 218 | n_rcvd += 1 |
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| 219 | if ok: |
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| 220 | n_right += 1 |
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| 221 | |
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| 222 | mods = modulation_utils.type_1_mods() |
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| 223 | demods = modulation_utils.type_1_demods() |
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| 224 | |
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| 225 | # Set default values for the CROSS shell location. These can be overridden |
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| 226 | # via command-line parameters |
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| 227 | crossShellHost = "localhost" |
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| 228 | crossShellPort = "40000" |
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| 229 | |
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| 230 | #setting up the tx options parser |
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| 231 | |
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| 232 | parser_tx = OptionParser(option_class=eng_option, conflict_handler="resolve") |
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| 233 | |
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| 234 | parser_tx.add_option("-m", "--modulation", type="choice", choices=mods.keys(), |
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| 235 | default='gmsk',help="Select modulation from: %s [default=%%default]" |
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| 236 | % (', '.join(mods.keys()),)) |
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| 237 | parser_tx.add_option("-s", "--size", type="eng_float", default=1500, |
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| 238 | help="set packet size [default=%default]") |
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| 239 | parser_tx.add_option("-M", "--megabytes", type="eng_float", default=1.0, |
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| 240 | help="set megabytes to transmit [default=%default]") |
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| 241 | parser_tx.add_option("","--discontinuous", action="store_true", default=False, |
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| 242 | help="enable discontinous transmission (bursts of 5 packets)") |
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| 243 | parser_tx.add_option("","--from-file", default=None, |
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| 244 | help="use file for packet contents") |
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| 245 | parser_tx.add_option("-n", "--hostname", action="store", type="string", dest="crossShellHost", |
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| 246 | default="localhost", help="Set the hostname/IP for the VTCROSS shell"); |
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| 247 | parser_tx.add_option("-p", "--port", action="store", type="string", dest="crossShellPort", |
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| 248 | default="40000", help="Set the port for the VTCROSS shell"); |
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| 249 | |
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| 250 | expert_grp_tx = parser_tx.add_option_group("Expert_tx") |
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| 251 | dsa_grp = parser_tx.add_option_group("DSA Options") |
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| 252 | dsa_grp.add_option("-c", "--cross", action="store_true", default=False, |
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| 253 | help="Use the CROSS CBR Cognitive Engine for DSA channel decisions [default=off (random selection)].") |
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| 254 | |
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| 255 | dsa_grp.add_option("-T", "--threshold", type="eng_float", default=1.5e8, |
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| 256 | help="set primary user sensing energy threshold [default=%default]") |
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| 257 | |
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| 258 | |
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| 259 | usrp_transmit_path.add_options(parser_tx, expert_grp_tx) |
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| 260 | parser_tx.remove_option('-f'); |
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| 261 | parser_tx.remove_option('--tx-freq'); |
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| 262 | |
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| 263 | for mod in mods.values(): |
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| 264 | mod.add_options(expert_grp_tx) |
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| 265 | |
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| 266 | |
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| 267 | (options_tx, args_tx) = parser_tx.parse_args () |
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| 268 | |
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| 269 | if len(args_tx) != 0: |
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| 270 | parser_tx.print_help() |
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| 271 | sys.exit(1) |
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| 272 | |
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| 273 | ############# Setting some default values for tx side of the block |
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| 274 | options_tx.tx_freq = 462.5625e6 |
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| 275 | options_tx.samples_per_symbol = 2 |
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| 276 | options_tx.modulation = 'dbpsk' |
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| 277 | options_tx.fusb_block_size = 4096 |
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| 278 | options_tx.fusb_nblocks = 16 |
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| 279 | options_tx.bitrate = 0.0125e6 |
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| 280 | ############# |
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| 281 | |
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| 282 | if options_tx.tx_freq is None: |
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| 283 | sys.stderr.write("You must specify -f FREQ or --freq FREQ\n") |
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| 284 | parser_tx.print_help(sys.stderr) |
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| 285 | sys.exit(1) |
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| 286 | |
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| 287 | parser_rx = OptionParser (option_class=eng_option, conflict_handler="resolve") |
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| 288 | expert_grp_rx = parser_rx.add_option_group("Expert_rx") |
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| 289 | usrp_receive_path.add_options(parser_rx, expert_grp_rx) |
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| 290 | |
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| 291 | parser_rx.remove_option('-f'); |
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| 292 | |
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| 293 | parser_rx.add_option("-c", "--cross", action="store_true", default=False, |
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| 294 | help="Use the CROSS engine for DSA decisions: default is random.") |
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| 295 | parser_rx.add_option("-T", "--threshold", type="eng_float", default=1.5e8, |
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| 296 | help="set primary user sensing energy threshold [default=%default]") |
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| 297 | parser_rx.add_option("-n", "--hostname", action="store", type="string", dest="crossShellHost", |
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| 298 | default="localhost", help="Set the hostname/IP for the VTCROSS shell"); |
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| 299 | parser_rx.add_option("-p", "--port", action="store", type="string", dest="crossShellPort", |
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| 300 | default="40000", help="Set the port for the VTCROSS shell"); |
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| 301 | |
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| 302 | |
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| 303 | |
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| 304 | (options_rx, args_rx) = parser_rx.parse_args () |
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| 305 | |
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| 306 | ############# Setting some default values for rx side of the block |
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| 307 | options_rx.rx_freq = 462.5625e6 #setting default rx_freq value |
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| 308 | options_rx.samples_per_symbol = 2 |
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| 309 | options_rx.modulation = 'dbpsk' |
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| 310 | options_rx.fusb_block_size = 4096 |
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| 311 | options_rx.fusb_nblocks = 16 |
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| 312 | options_rx.bitrate = 0.0125e6 |
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| 313 | ############# |
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| 314 | |
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| 315 | |
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| 316 | if options_rx.cross == True: |
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| 317 | if cross_import == False: |
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| 318 | print "\n\n[[ CROSS Import failed.. Defaulting to RANDOM channel selection ]]" |
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| 319 | print "[[ Using the RANDOM channel selection algorithm ]]\n\n" |
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| 320 | options_rx.cross = False |
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| 321 | else: |
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| 322 | print "[[ Using the CROSS DSA Cognitive Engine ]]" |
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| 323 | crossShellHost = options_rx.crossShellHost |
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| 324 | crossShellPort = options_rx.crossShellPort |
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| 325 | print "[[ VTCROSS shell located at " + crossShellHost + ":" + crossShellPort + " ]]" |
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| 326 | SetCrossShellLocation(crossShellHost, crossShellPort) |
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| 327 | else: |
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| 328 | print "[[ Using the RANDOM channel selection algorithm ]]\n\n" |
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| 329 | |
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| 330 | # build the graph |
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| 331 | print "printing modulation scheme",demods[options_rx.modulation] |
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| 332 | tb = my_top_block(mods[options_tx.modulation], |
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| 333 | demods[options_rx.modulation], |
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| 334 | rx_callback,options_tx, |
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| 335 | options_rx) |
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| 336 | r = gr.enable_realtime_scheduling() |
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| 337 | if r != gr.RT_OK: |
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| 338 | print "Warning: failed to enable realtime scheduling" |
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| 339 | |
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| 340 | tb.start() |
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| 341 | |
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| 342 | #listening to random frequencies untill a match is found |
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| 343 | running = True |
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| 344 | ch_energy = tb.rxpath.probe.level() #setting initial value |
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| 345 | hop_freq = options_tx.tx_freq # = options_rx.rx_freq...same for tx and rx side |
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| 346 | |
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| 347 | # Scan all channels first for inital data |
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| 348 | #time.sleep(0.1) |
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| 349 | |
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| 350 | print "\n[[ Scanning channels for network nodes ]]\n" |
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| 351 | while running: |
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| 352 | ################################################sync mode#################################### |
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| 353 | if mode == "sync": |
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| 354 | if sync_status != True: |
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| 355 | |
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| 356 | if return_flag == 0: |
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| 357 | ch,hop_freq = get_freq(hop_freq,ch_energy,0,options_rx.cross) |
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| 358 | else: |
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| 359 | ch,hop_freq = get_freq(hop_freq,ch_energy,elapsed_time,options_rx.cross) |
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| 360 | return_flag = 0 |
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| 361 | |
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| 362 | tb.txpath.u.set_center_freq(hop_freq) |
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| 363 | tb.rxpath.u.set_center_freq(hop_freq) |
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| 364 | |
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| 365 | ch_energy = tb.rxpath.probe.level() #check if primary user is present |
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| 366 | |
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| 367 | if int(ch_energy) > 1.5e8: #if primary user is there then dont transmit on this channel |
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| 368 | continue |
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| 369 | |
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| 370 | nbytes = 5 #int(1e6 * .0003) |
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| 371 | pkt_size = 5 |
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| 372 | n = 0 |
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| 373 | pktno = 0 |
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| 374 | while n < nbytes: |
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| 375 | if options_tx.from_file is None: |
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| 376 | data = 's' |
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| 377 | else: |
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| 378 | data = source_file.read(pkt_size - 2) |
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| 379 | if data == '': |
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| 380 | break; |
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| 381 | |
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| 382 | payload = struct.pack('!HsH', pktno & 0xffff,data,ch & 0xffff) #+ data |
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| 383 | |
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| 384 | send_pkt(tb,payload) |
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| 385 | n += len(payload) |
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| 386 | sys.stderr.write('.') |
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| 387 | if options_tx.discontinuous and pktno % 5 == 4: |
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| 388 | time.sleep(1) |
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| 389 | pktno += 1 |
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| 390 | time.sleep(0.1) |
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| 391 | |
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| 392 | else: |
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| 393 | print "\n\n[[ Network Node Found: Commencing communications on CHANNEL ", ch, " ]]\n"; |
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| 394 | n_attempts_counter = 0 |
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| 395 | mode = "traffic" |
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| 396 | traffic_flag = False |
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| 397 | sync_status="False" |
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| 398 | start_time = datetime.now() #measuring the time for which the primary user is away |
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| 399 | |
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| 400 | ################################################end of sync mode#################################### |
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| 401 | |
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| 402 | ################################################Communications mode################################# |
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| 403 | if mode == "traffic": |
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| 404 | nbytes = 15 |
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| 405 | pkt_size = 15 |
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| 406 | data_pktno = 0 |
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| 407 | n = 0 |
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| 408 | while n < nbytes: |
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| 409 | if options_tx.from_file is None: |
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| 410 | data = 'dHi how are you' #Sending this message |
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| 411 | else: |
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| 412 | data = source_file.read(pkt_size - 2) |
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| 413 | if data == '': |
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| 414 | break; |
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| 415 | |
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| 416 | |
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| 417 | payload = struct.pack('!15s', data) |
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| 418 | |
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| 419 | send_pkt(tb,payload) |
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| 420 | n += len(payload) |
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| 421 | sys.stderr.write('.') |
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| 422 | if options_tx.discontinuous and data_pktno % 5 == 4: |
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| 423 | time.sleep(1) |
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| 424 | data_pktno += 1 |
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| 425 | time.sleep(0.2 + 0.05*int(random.choice([0,1,2,3]))) |
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| 426 | |
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| 427 | if traffic_flag != True: |
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| 428 | n_attempts_counter += 1 |
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| 429 | if n_attempts_counter > n_attempts: #get out of the data channel as it seems that the other node is still trying to rendezvous |
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| 430 | mode = "sync" |
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| 431 | continue |
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| 432 | |
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| 433 | #ch_energy = tb.rxpath.probe.level() #check if primary user is present |
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| 434 | time_right_now = datetime.now() |
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| 435 | #print "inside traffic , ticker_start",ticker_start |
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| 436 | packet_delay = (time_right_now - ticker_start).seconds |
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| 437 | #print "packet_delay ",packet_delay |
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| 438 | if packet_delay >= no_packet_period: |
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| 439 | stop_time = datetime.now() |
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| 440 | _elapsed_time = start_time - stop_time |
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| 441 | elapsed_time = _elapsed_time.seconds |
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| 442 | print "\n[[ No data packets: Evacuating Current Channel ]]\n" |
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| 443 | print "\n[[ Scanning channels for network nodes ]]\n" |
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| 444 | mode = "sync" |
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| 445 | mode = "sync" |
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| 446 | return_flag = 1 |
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| 447 | |
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| 448 | |
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| 449 | #if int(ch_energy) > 1.5e8: #if primary user is there then dont transmit on this channel |
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| 450 | |
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| 451 | |
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| 452 | |
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| 453 | if __name__ == '__main__': |
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| 454 | try: |
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| 455 | main() |
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| 456 | except KeyboardInterrupt: |
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| 457 | pass |
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| 458 | |
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