-#!/usr/bin/env python

-#

-# Copyright 2004,2005,2006 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 2, 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

-from optparse import OptionParser

-from ofdm_receiver import ofdm_receiver

-

-class ofdm_mod(gr.hier_block):

- def __init__(self, fg, options):

- self.fg = fg

- self._occupied_tones = options.occupied_tones

- self._fft_length = options.fft_length

- self._cp_length = options.cp_length

- self._mtu = options.mtu

-

- symbol_length = self._fft_length + self._cp_length

-

- if self._fft_length < self._occupied_tones:

- sys.stderr.write("occupied tones must be less than FFT length\n")

- raise SystemExit

- if self._fft_length < self._cp_length:

- sys.stderr.write("cyclic prefix length must be less than FFT length\n")

- raise SystemExit

-

- win = [] #[1 for i in range(self._fft_length)]

-

- # hard-coded known symbol

- #ks = self._occupied_tones*[1,]

- ks1 = known_symbols_200_1

- ks2 = known_symbols_200_2

-

- self.ofdm = gr.ofdm_bpsk_mapper(self._mtu, self._occupied_tones, self._fft_length, ks1, ks2)

- self.ifft = gr.fft_vcc(self._fft_length, False, win, True)

- self.cp_adder = gr.ofdm_cyclic_prefixer(self._fft_length, symbol_length)

-

- if options.verbose:

- self._print_verbage()

-

- self.fg.connect(self.ofdm, self.ifft, self.cp_adder)

- gr.hier_block.__init__(self, self.fg, self.ofdm, self.cp_adder)

-

- def samples_per_symbol(self):

- return 2

-

- def mtu(self):

- return self._mtu

-

- def bits_per_symbol(self=None): # staticmethod that's also callable on an instance

- return 1

- bits_per_symbol = staticmethod(bits_per_symbol) # make it a static method. RTFM

-

- def add_options(normal, expert):

- """

- Adds OFDM-specific options to the Options Parser

- """

- expert.add_option("", "--mtu", type="int", default=1500,

- help="set maximum transmit unit [default=%default]")

- expert.add_option("", "--fft-length", type="intx", default=512,

- help="set the number of FFT bins [default=%default]")

- expert.add_option("", "--occupied-tones", type="intx", default=200,

- help="set the number of occupied FFT bins [default=%default]")

- expert.add_option("", "--cp-length", type="intx", default=128,

- help="set the number of bits in the cyclic prefix [default=%default]")

- # Make a static method to call before instantiation

- add_options = staticmethod(add_options)

-

- def _print_verbage(self):

- """

- Prints information about the OFDM modulator

- """

- print "\nOFDM Modulator:"

- print "FFT length: %3d" % (self._fft_length)

- print "Occupied Tones: %3d" % (self._occupied_tones)

- print "CP length: %3d" % (self._cp_length)

-

-

-class ofdm_demod(gr.hier_block):

- def __init__(self, fg, options):

- self.fg = fg

- self._occupied_tones = options.occupied_tones

- self._fft_length = options.fft_length

- self._cp_length = options.cp_length

- self._snr = options.snr

-

- symbol_length = self._fft_length + self._cp_length

-

- win = [1 for i in range(self._fft_length)]

-

- # hard-coded known symbol

- ks1 = known_symbols_200_1

- ks2 = known_symbols_200_2

-

- # ML Sync

- self.ofdm_sync = ofdm_receiver(self.fg, self._fft_length, symbol_length, self._snr)

-

- # OFDM Demod

- self.fft_demod = gr.fft_vcc(self._fft_length, True, win, True)

- self.ofdm_corr = gr.ofdm_correlator(self._occupied_tones, self._fft_length,

- self._cp_length, ks1, ks2)

- self.ofdm_demod = gr.ofdm_bpsk_demapper(self._occupied_tones)

-

-

- if options.verbose:

- self._print_verbage()

-

- self.fg.connect(self.ofdm_sync, self.fft_demod, self.ofdm_corr, self.ofdm_demod)

- gr.hier_block.__init__(self, self.fg, self.ofdm_sync, self.ofdm_demod)

-

- def bits_per_symbol(self=None): # staticmethod that's also callable on an instance

- return 1

- bits_per_symbol = staticmethod(bits_per_symbol) # make it a static method. RTFM

-

- def add_options(normal, expert):

- """

- Adds OFDM-specific options to the Options Parser

- """

- expert.add_option("", "--fft-length", type="intx", default=512,

- help="set the number of FFT bins [default=%default]")

- expert.add_option("", "--occupied-tones", type="intx", default=200,

- help="set the number of occupied FFT bins [default=%default]")

- expert.add_option("", "--cp-length", type="intx", default=128,

- help="set the number of bits in the cyclic prefix [default=%default]")

- # Make a static method to call before instantiation

- add_options = staticmethod(add_options)

-

- def _print_verbage(self):

- """

- Prints information about the OFDM demodulator

- """

- print "\nOFDM Demodulator:"

- print "FFT length: %3d" % (self._fft_length)

- print "Occupied Tones: %3d" % (self._occupied_tones)

- print "CP length: %3d" % (self._cp_length)

-

-

-# generated in python using:

-# import random

-# pn = [2.0*random.randint(0,1)-1.0 for i in range(self._occupied_tones)]

-

-known_symbols_200_1 = [1.0, 1.0, -1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0]

-

-known_symbols_200_2 = [-1.0, -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0]