def make_prs(sample_rate=2048000):
dp = parameters.dab_parameters(1, sample_rate)
prs = dp.prn
def write(file_name, signal):
if type(signal) != numpy.complex64:
signal = numpy.asarray(signal, dtype=numpy.complex64)
signal.tofile(file_name)
def interleave(symbol):
return [symbol[i] for i in dp.frequency_interleaving_sequence_array]
def pad(symbol):
zeros_on_left = (dp.fft_length - dp.num_carriers) / 2
zeros_on_right = dp.fft_length - zeros_on_left - dp.num_carriers - 1
return [0] * zeros_on_left + symbol[0:dp.num_carriers / 2] + [
0
] + symbol[dp.num_carriers / 2:] + [0] * zeros_on_right
#print prs
interleaved_prs = interleave(prs)
#padded_prs = pad(interleaved_prs)
padded_prs = pad(prs)
return padded_prs
def __init__(self): gr.top_block.__init__(self) usage = "%prog: [options] samples_file" parser = OptionParser(option_class=eng_option, usage=usage) (options, args) = parser.parse_args () if len(args)<1: # print "using gaussian noise as source" # self.sigsrc = gr.noise_source_c(gr.GR_GAUSSIAN,10e6) print "using repeating random vector as source" self.sigsrc = blocks.vector_source_c([10e6*(random.random() + 1j*random.random()) for i in range(0,100000)],True) self.src = blocks.throttle( gr.sizeof_gr_complex,2048000) self.connect(self.sigsrc, self.src) else: filename = args[0] print "using samples from file " + filename self.src = blocks.file_source(gr.sizeof_gr_complex, filename, False) dp = parameters.dab_parameters(1) rp = parameters.receiver_parameters(1) self.sync_dab = ofdm_sync_dab(dp, rp, False) self.nop0 = blocks.nop(gr.sizeof_gr_complex) self.nop1 = blocks.nop(gr.sizeof_char) self.connect(self.src, self.sync_dab, self.nop0) self.connect((self.sync_dab,1), self.nop1)
def __init__(self):
gr.sync_block.__init__(self,
name="dab_sync",
in_sig=[numpy.complex64],
out_sig=[numpy.complex64])
self.sample_rate = 2048000
self.step = 1
self.dp = parameters.dab_parameters(1, self.sample_rate)
self.prs = make_prs.modulate_prs(self.sample_rate, True)
self.frame_length = int(self.sample_rate * 96e-3)
self.prs_len = len(self.prs)
print "PRS length", self.prs_len
self.correlator = correlate.Correlator(self.prs, self.sample_rate)
self.P = 0.2 * 3
self.I = 0.2 * 3
self.fract = 1000
self.integer_offset = 0
self.fract_offset = 0
self.state = INIT
self.set_history(self.prs_len + 1)
def __init__(self):
gr.top_block.__init__(self)
usage = "%prog: [options] samples_file"
parser = OptionParser(option_class=eng_option, usage=usage)
(options, args) = parser.parse_args()
if len(args) < 1:
# print "using gaussian noise as source"
# self.sigsrc = gr.noise_source_c(gr.GR_GAUSSIAN,10e6)
print "using repeating random vector as source"
self.sigsrc = blocks.vector_source_c([
10e6 * (random.random() + 1j * random.random())
for i in range(0, 100000)
], True)
self.src = blocks.throttle(gr.sizeof_gr_complex, 2048000)
self.connect(self.sigsrc, self.src)
else:
filename = args[0]
print "using samples from file " + filename
self.src = blocks.file_source(gr.sizeof_gr_complex, filename,
False)
dp = parameters.dab_parameters(1)
rp = parameters.receiver_parameters(1)
self.sync_dab = ofdm_sync_dab(dp, rp, False)
self.nop0 = blocks.nop(gr.sizeof_gr_complex)
self.nop1 = blocks.nop(gr.sizeof_char)
self.connect(self.src, self.sync_dab, self.nop0)
self.connect((self.sync_dab, 1), self.nop1)
def test_001_t (self):
self.symbol_length = 32*4
self.dab_params = dab_parameters(1, 208.064e6, True)
# source
self.dp = dab_parameters(1, 208.064e6, True)
self.fib_src = dab.fib_source_b_make(1, 1, 1, "ensemble1", "service1 ", "musicmix", 4, [2], [15], [1])
# encoder
self.fib_enc = fic_encode(self.dab_params)
self.unpack = blocks.packed_to_unpacked_bb_make(1, gr.GR_MSB_FIRST)
# mapper
self.map = dab.mapper_bc_make(self.dp.num_carriers)
# demapper
self.s2v = blocks.stream_to_vector_make(gr.sizeof_gr_complex, self.dp.num_carriers)
self.soft_interleaver = dab.complex_to_interleaved_float_vcf_make(self.dp.num_carriers)
# decode
self.fic_decoder = fic_decode(self.dab_params)
# control stream
self.trigger_src = blocks.vector_source_b([1] + [0]*74, True)
self.tb.connect(self.fib_src,
blocks.head_make(gr.sizeof_char, 100000),
self.fib_enc,
self.unpack,
self.map,
self.s2v,
self.soft_interleaver,
self.fic_decoder
)
self.tb.connect(self.trigger_src, (self.fic_decoder, 1))
self.tb.run ()
pass
def __init__(self):
gr.top_block.__init__(self)
usage = "%prog: [options] samples_file"
parser = OptionParser(option_class=eng_option, usage=usage)
parser.add_option("-m", "--dab-mode", type="int", default=1,
help="DAB mode [default=%default]")
parser.add_option("-F", "--filter-input", action="store_true", default=False,
help="Enable FFT filter at input")
parser.add_option("-s", "--resample-fixed", type="float", default=1,
help="resample by a fixed factor (fractional interpolation)")
parser.add_option("-S", "--autocorrect-sample-rate", action="store_true", default=False,
help="Estimate sample rate offset and resample (dynamic fractional interpolation)")
parser.add_option('-r', '--sample-rate', type="int", default=2048000,
help="Use non-standard sample rate (default=%default)")
parser.add_option('-e', '--equalize-magnitude', action="store_true", default=False,
help="Enable individual carrier magnitude equalizer")
parser.add_option('-d', '--debug', action="store_true", default=False,
help="Write output to files")
parser.add_option('-v', '--verbose', action="store_true", default=False,
help="Print status messages")
(options, args) = parser.parse_args ()
dp = parameters.dab_parameters(options.dab_mode, verbose=options.verbose, sample_rate=options.sample_rate)
rp = parameters.receiver_parameters(options.dab_mode, input_fft_filter=options.filter_input, autocorrect_sample_rate=options.autocorrect_sample_rate, sample_rate_correction_factor=options.resample_fixed, equalize_magnitude=options.equalize_magnitude, verbose=options.verbose)
if len(args)<1:
if options.verbose: print "-> using repeating random vector as source"
self.sigsrc = gr.vector_source_c([10e6*(random.random() + 1j*random.random()) for i in range(0,100000)],True)
self.ns_simulate = gr.vector_source_c([0.01]*dp.ns_length+[1]*dp.symbols_per_frame*dp.symbol_length,1)
self.mult = gr.multiply_cc() # simulate null symbols ...
self.src = gr.throttle( gr.sizeof_gr_complex,2048000)
self.connect(self.sigsrc, (self.mult, 0))
self.connect(self.ns_simulate, (self.mult, 1))
self.connect(self.mult, self.src)
else:
filename = args[0]
if options.verbose: print "-> using samples from file " + filename
self.src = gr.file_source(gr.sizeof_gr_complex, filename, False)
self.dab_demod = ofdm.ofdm_demod(dp, rp, debug=options.debug, verbose=options.verbose)
self.connect(self.src, self.dab_demod)
# sink output to nowhere
self.nop0 = gr.nop(gr.sizeof_char*dp.num_carriers/4)
self.nop1 = gr.nop(gr.sizeof_char)
self.connect((self.dab_demod,0),self.nop0)
self.connect((self.dab_demod,1),self.nop1)
def init(self):
self.sample_rate = 2048000
self.step = 1
self.dp = parameters.dab_parameters(1, self.sample_rate)
self.prs = make_prs.modulate_prs(self.sample_rate, True)
self.frame_length = int(self.sample_rate * 96e-3)
self.prs_len = len(self.prs)
self.P = 0.2 * 3
self.I = 0.2 * 3
self.fract = 1000
self.integer_offset = 0
self.fract_offset = 0
self.state = get_samples
self.get_samples_count = self.frame_length
self.next_state = find_start
def modulate_prs(sample_rate=2048000, cp=True):
dp = parameters.dab_parameters(1, sample_rate)
padded_prs = make_prs(sample_rate)
#plt.plot(numpy.abs(padded_prs))
#plt.show()
#plt.plot(numpy.angle(padded_prs))
#plt.show()
shifted_prs = numpy.fft.fftshift(padded_prs)
#plt.plot(numpy.abs(shifted_prs))
#plt.show()
ifft_prs = numpy.fft.ifft(shifted_prs)
if cp:
print "CP length", dp.cp_length
cycled_prs = numpy.concatenate((ifft_prs[-dp.cp_length:], ifft_prs))
return cycled_prs
else:
return ifft_prs
if __name__ == "__main__":
#sample_rate = 2048000
sample_rate = 2000000
cycled_prs = modulate_prs(sample_rate)
iq.write("/tmp/generated.cfile", cycled_prs)
signal = numpy.concatenate(([0] * 2048, cycled_prs))
#signal = numpy.concatenate(([0] * 2048, cycled_prs, [0] * 2048, cycled_prs))
#signal = numpy.concatenate(([0] * 2048, prs, [0] * 2048, prs))
iq.write("/tmp/foo.cfile", signal)
#print dp.frequency_interleaving_sequence_array
dp = parameters.dab_parameters(1, sample_rate)
Tu = dp.fft_length
offset = 600
shift_signal = numpy.exp(
complex(0, -1) * numpy.arange(len(signal)) * 2 * numpy.pi * offset /
float(sample_rate))
signal = signal * shift_signal
time_shifted_signal = signal[Tu:]
auto_correlated = [0] * len(time_shifted_signal)
for i in range(len(time_shifted_signal)):
auto_correlated[i] = numpy.angle(signal[i] * numpy.conj(
time_shifted_signal[i])) / 2 / 3.14 / (2048. / sample_rate)
def __init__(self):
gr.top_block.__init__(self)
usage = "%prog: [options] samples_file"
parser = OptionParser(option_class=eng_option, usage=usage)
parser.add_option("-m",
"--dab-mode",
type="int",
default=1,
help="DAB mode [default=%default]")
parser.add_option("-F",
"--filter-input",
action="store_true",
default=False,
help="Enable FFT filter at input")
parser.add_option(
"-s",
"--resample-fixed",
type="float",
default=1,
help="resample by a fixed factor (fractional interpolation)")
parser.add_option(
"-S",
"--autocorrect-sample-rate",
action="store_true",
default=False,
help=
"Estimate sample rate offset and resample (dynamic fractional interpolation)"
)
parser.add_option(
'-r',
'--sample-rate',
type="int",
default=2048000,
help="Use non-standard sample rate (default=%default)")
parser.add_option('-e',
'--equalize-magnitude',
action="store_true",
default=False,
help="Enable individual carrier magnitude equalizer")
parser.add_option('-d',
'--debug',
action="store_true",
default=False,
help="Write output to files")
parser.add_option('-v',
'--verbose',
action="store_true",
default=False,
help="Print status messages")
(options, args) = parser.parse_args()
dp = parameters.dab_parameters(options.dab_mode,
verbose=options.verbose,
sample_rate=options.sample_rate)
rp = parameters.receiver_parameters(
options.dab_mode,
input_fft_filter=options.filter_input,
autocorrect_sample_rate=options.autocorrect_sample_rate,
sample_rate_correction_factor=options.resample_fixed,
equalize_magnitude=options.equalize_magnitude,
verbose=options.verbose)
if len(args) < 1:
if options.verbose:
print "-> using repeating random vector as source"
self.sigsrc = blocks.vector_source_c([
10e6 * (random.random() + 1j * random.random())
for i in range(0, 100000)
], True)
self.ns_simulate = blocks.vector_source_c(
[0.01] * dp.ns_length +
[1] * dp.symbols_per_frame * dp.symbol_length, 1)
self.mult = blocks.multiply_cc() # simulate null symbols ...
self.src = blocks.throttle(gr.sizeof_gr_complex, 2048000)
self.connect(self.sigsrc, (self.mult, 0))
self.connect(self.ns_simulate, (self.mult, 1))
self.connect(self.mult, self.src)
else:
filename = args[0]
if options.verbose: print "-> using samples from file " + filename
self.src = blocks.file_source(gr.sizeof_gr_complex, filename,
False)
self.dab_demod = ofdm.ofdm_demod(dp,
rp,
debug=options.debug,
verbose=options.verbose)
self.connect(self.src, self.dab_demod)
# sink output to nowhere
self.nop0 = blocks.nop(gr.sizeof_char * dp.num_carriers / 4)
self.nop1 = blocks.nop(gr.sizeof_char)
self.connect((self.dab_demod, 0), self.nop0)
self.connect((self.dab_demod, 1), self.nop1)
def __init__(self, mode, debug=False):
"""
OFDM time and coarse frequency synchronisation for DAB
@param mode DAB mode (1-4)
@param debug if True: write data streams out to files
"""
if mode < 1 or mode > 4:
raise ValueError, "Invalid DAB mode: " + str(
mode) + " (modes 1-4 exist)"
# get the correct DAB parameters
dp = parameters.dab_parameters(mode)
rp = parameters.receiver_parameters(mode)
gr.hier_block2.__init__(
self,
"ofdm_sync_dab",
gr.io_signature(1, 1, gr.sizeof_gr_complex), # input signature
gr.io_signature2(2, 2, gr.sizeof_gr_complex,
gr.sizeof_char)) # output signature
# workaround for a problem that prevents connecting more than one block directly (see trac ticket #161)
self.input = gr.kludge_copy(gr.sizeof_gr_complex)
self.connect(self, self.input)
#
# null-symbol detection
#
# (outsourced to detect_zero.py)
self.ns_detect = detect_null.detect_null(dp.ns_length, debug)
self.connect(self.input, self.ns_detect)
#
# fine frequency synchronisation
#
# the code for fine frequency synchronisation is adapted from
# ofdm_sync_ml.py; it abuses the cyclic prefix to find the fine
# frequency error, as suggested in "ML Estimation of Timing and
# Frequency Offset in OFDM Systems", by Jan-Jaap van de Beek,
# Magnus Sandell, Per Ola Börjesson, see
# http://www.sm.luth.se/csee/sp/research/report/bsb96r.html
self.ffs_delay = gr.delay(gr.sizeof_gr_complex, dp.fft_length)
self.ffs_conj = gr.conjugate_cc()
self.ffs_mult = gr.multiply_cc()
# self.ffs_moving_sum = gr.fir_filter_ccf(1, [1]*dp.cp_length)
self.ffs_moving_sum = dab_swig.moving_sum_cc(dp.cp_length)
self.ffs_angle = gr.complex_to_arg()
self.ffs_angle_scale = gr.multiply_const_ff(1. / dp.fft_length)
self.ffs_delay_sample_and_hold = gr.delay(
gr.sizeof_char,
dp.symbol_length) # sample the value at the end of the symbol ..
self.ffs_sample_and_hold = gr.sample_and_hold_ff()
self.ffs_delay_input_for_correction = gr.delay(
gr.sizeof_gr_complex, dp.symbol_length
) # by delaying the input, we can use the ff offset estimation from the first symbol to correct the first symbol itself
self.ffs_nco = gr.frequency_modulator_fc(
1) # ffs_sample_and_hold directly outputs phase error per sample
self.ffs_mixer = gr.multiply_cc()
# calculate fine frequency error
self.connect(self.input, self.ffs_conj, self.ffs_mult)
self.connect(self.input, self.ffs_delay, (self.ffs_mult, 1))
self.connect(self.ffs_mult, self.ffs_moving_sum, self.ffs_angle)
# only use the value from the first half of the first symbol
self.connect(self.ffs_angle, self.ffs_angle_scale,
(self.ffs_sample_and_hold, 0))
self.connect(self.ns_detect, self.ffs_delay_sample_and_hold,
(self.ffs_sample_and_hold, 1))
# do the correction
self.connect(self.ffs_sample_and_hold, self.ffs_nco,
(self.ffs_mixer, 0))
self.connect(self.input, self.ffs_delay_input_for_correction,
(self.ffs_mixer, 1))
# output - corrected signal and start of DAB frames
self.connect(self.ffs_mixer, (self, 0))
self.connect(self.ffs_delay_sample_and_hold, (self, 1))
if debug:
self.connect(
self.ffs_angle,
gr.file_sink(gr.sizeof_float,
"debug/ofdm_sync_dab_ffs_angle.dat"))
self.connect(
self.ffs_sample_and_hold,
gr.multiply_const_ff(1. / (dp.T * 2 * pi)),
gr.file_sink(gr.sizeof_float,
"debug/ofdm_sync_dab_fine_freq_err_f.dat"))
self.connect(
self.ffs_mixer,
gr.file_sink(gr.sizeof_gr_complex,
"debug/ofdm_sync_dab_fine_freq_corrected_c.dat"))
def __init__(self, mode, debug=False): """ OFDM time and coarse frequency synchronisation for DAB @param mode DAB mode (1-4) @param debug if True: write data streams out to files """ if mode<1 or mode>4: raise ValueError, "Invalid DAB mode: "+str(mode)+" (modes 1-4 exist)" # get the correct DAB parameters dp = parameters.dab_parameters(mode) rp = parameters.receiver_parameters(mode) gr.hier_block2.__init__(self,"ofdm_sync_dab", gr.io_signature(1, 1, gr.sizeof_gr_complex), # input signature gr.io_signature2(2, 2, gr.sizeof_gr_complex, gr.sizeof_char)) # output signature # workaround for a problem that prevents connecting more than one block directly (see trac ticket #161) self.input = gr.kludge_copy(gr.sizeof_gr_complex) self.connect(self, self.input) # # null-symbol detection # # (outsourced to detect_zero.py) self.ns_detect = detect_null.detect_null(dp.ns_length, debug) self.connect(self.input, self.ns_detect) # # fine frequency synchronisation # # the code for fine frequency synchronisation is adapted from # ofdm_sync_ml.py; it abuses the cyclic prefix to find the fine # frequency error, as suggested in "ML Estimation of Timing and # Frequency Offset in OFDM Systems", by Jan-Jaap van de Beek, # Magnus Sandell, Per Ola Börjesson, see # http://www.sm.luth.se/csee/sp/research/report/bsb96r.html self.ffs_delay = gr.delay(gr.sizeof_gr_complex, dp.fft_length) self.ffs_conj = gr.conjugate_cc() self.ffs_mult = gr.multiply_cc() # self.ffs_moving_sum = gr.fir_filter_ccf(1, [1]*dp.cp_length) self.ffs_moving_sum = dab_swig.moving_sum_cc(dp.cp_length) self.ffs_angle = gr.complex_to_arg() self.ffs_angle_scale = gr.multiply_const_ff(1./dp.fft_length) self.ffs_delay_sample_and_hold = gr.delay(gr.sizeof_char, dp.symbol_length) # sample the value at the end of the symbol .. self.ffs_sample_and_hold = gr.sample_and_hold_ff() self.ffs_delay_input_for_correction = gr.delay(gr.sizeof_gr_complex, dp.symbol_length) # by delaying the input, we can use the ff offset estimation from the first symbol to correct the first symbol itself self.ffs_nco = gr.frequency_modulator_fc(1) # ffs_sample_and_hold directly outputs phase error per sample self.ffs_mixer = gr.multiply_cc() # calculate fine frequency error self.connect(self.input, self.ffs_conj, self.ffs_mult) self.connect(self.input, self.ffs_delay, (self.ffs_mult, 1)) self.connect(self.ffs_mult, self.ffs_moving_sum, self.ffs_angle) # only use the value from the first half of the first symbol self.connect(self.ffs_angle, self.ffs_angle_scale, (self.ffs_sample_and_hold, 0)) self.connect(self.ns_detect, self.ffs_delay_sample_and_hold, (self.ffs_sample_and_hold, 1)) # do the correction self.connect(self.ffs_sample_and_hold, self.ffs_nco, (self.ffs_mixer, 0)) self.connect(self.input, self.ffs_delay_input_for_correction, (self.ffs_mixer, 1)) # output - corrected signal and start of DAB frames self.connect(self.ffs_mixer, (self, 0)) self.connect(self.ffs_delay_sample_and_hold, (self, 1)) if debug: self.connect(self.ffs_angle, gr.file_sink(gr.sizeof_float, "debug/ofdm_sync_dab_ffs_angle.dat")) self.connect(self.ffs_sample_and_hold, gr.multiply_const_ff(1./(dp.T*2*pi)), gr.file_sink(gr.sizeof_float, "debug/ofdm_sync_dab_fine_freq_err_f.dat")) self.connect(self.ffs_mixer, gr.file_sink(gr.sizeof_gr_complex, "debug/ofdm_sync_dab_fine_freq_corrected_c.dat"))
