Hi,
I am trying to do DBPSK modulation/demodulation using USRP1 and RFX1800. I run benchmark_tx at the transmitter side and rx at the receiver side. It worked great but I could not understand what packages I sent. So I am not sure about the modulation which I run , is correct or not ?
Does anybody know how can I see the packages that I sent by using benchmark_tx ??
Code :
#!/usr/bin/env python
#
# Copyright 2005,2006,2007,2009 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, gru, modulation_utils
from gnuradio import usrp
from gnuradio import eng_notation
from gnuradio.eng_option import eng_option
from optparse import OptionParser
import random, time,
struct, sys
# from current dir
import usrp_transmit_path
#import os
#print os.getpid()
#raw_input('Attach and press enter')
class my_top_block(gr.top_block):
def __init__(self, modulator, options):
gr.top_block.__init__(self)
self.txpath = usrp_transmit_path.usrp_transmit_path(modulator, options)
self.connect(self.txpath)
# /////////////////////////////////////////////////////////////////////////////
# main
# /////////////////////////////////////////////////////////////////////////////
def main():
def
send_pkt(payload='', eof=False):
return tb.txpath.send_pkt(payload, eof)
def rx_callback(ok, payload):
print "ok = %r, payload = '%s'" % (ok, payload)
mods = modulation_utils.type_1_mods()
parser = OptionParser(option_class=eng_option, conflict_handler="resolve")
expert_grp = parser.add_option_group("Expert")
parser.add_option("-m", "--modulation", type="choice", choices=mods.keys(),
default='gmsk',
help="Select modulation from: %s
[default=%%default]"
% (', '.join(mods.keys()),))
parser.add_option("-s", "--size", type="eng_float", default=1500,
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("","--discontinuous", action="",
default=False,
help="enable discontinous transmission (bursts of 5 packets)")
parser.add_option("","--from-file", default=None,
help="use file for packet contents")
usrp_transmit_path.add_options(parser, expert_grp)
for mod in mods.values():
mod.add_options(expert_grp)
(options, args) = parser.parse_args ()
if len(args) != 0:
parser.print_help()
sys.exit(1)
if options.tx_freq is
None:
sys.stderr.write("You must specify -f FREQ or --freq FREQ\n")
parser.print_help(sys.stderr)
sys.exit(1)
if options.from_file is not None:
source_file = open(options.from_file, 'r')
# build the graph
tb = my_top_block(mods[options.modulation], 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:
if options.from_file is None:
data = "" - 2) * chr(pktno & 0xff)
else:
data = "" - 2)
if data == '':
break;
payload = struct.pack('!H', pktno & 0xffff) + data
send_pkt(payload)
n += len(payload)
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 finish
if __name__ == '__main__':
try:
main()
except KeyboardInterrupt:
pass
MERVE....