diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/lib/gsm_constants.h | 2 | ||||
| -rw-r--r-- | src/lib/gsm_receiver_cf.cc | 16 | ||||
| -rw-r--r-- | src/lib/gsm_receiver_cf.h | 2 | ||||
| -rwxr-xr-x | src/python/gsm_findfcch_usrp.py | 122 |
4 files changed, 15 insertions, 127 deletions
diff --git a/src/lib/gsm_constants.h b/src/lib/gsm_constants.h index 3f7ef04..1ebce1c 100644 --- a/src/lib/gsm_constants.h +++ b/src/lib/gsm_constants.h @@ -33,6 +33,8 @@ #define CHAN_IMP_RESP_LENGTH 5 +#define MAX_SCH_ERRORS 2 //maximum number of subsequent sch errors after which gsm receiver goes to find_next_fcch state + typedef enum {empty, fcch_burst, sch_burst, normal_burst, rach_burst, dummy} burst_type; typedef enum {unknown, multiframe_26, multiframe_51} multiframe_type; diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc index 7f91fa8..0fde642 100644 --- a/src/lib/gsm_receiver_cf.cc +++ b/src/lib/gsm_receiver_cf.cc @@ -55,10 +55,10 @@ void gsm_receiver_cf::process_normal_burst(burst_counter burst_nr, const unsigne void gsm_receiver_cf::configure_receiver() { d_channel_conf.set_multiframe_type(TSC0, multiframe_51); - + d_channel_conf.set_burst_types(TSC0, TEST_CCH_FRAMES, sizeof(TEST_CCH_FRAMES) / sizeof(unsigned), normal_burst); d_channel_conf.set_burst_types(TSC0, FCCH_FRAMES, sizeof(FCCH_FRAMES) / sizeof(unsigned), fcch_burst); - + // d_channel_conf.set_multiframe_type(TIMESLOT6, multiframe_26); // d_channel_conf.set_burst_types(TIMESLOT6, TRAFFIC_CHANNEL_F, sizeof(TRAFFIC_CHANNEL_F) / sizeof(unsigned), normal_burst); } @@ -94,7 +94,8 @@ gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, int osr) d_fcch_start_pos(0), d_freq_offset(0), d_state(first_fcch_search), - d_burst_nr(osr) + d_burst_nr(osr), + d_failed_sch(0) { int i; gmsk_mapper(SYNC_BITS, N_SYNC_BITS, d_sch_training_seq, gr_complex(0.0, -1.0)); @@ -102,7 +103,7 @@ gsm_receiver_cf::gsm_receiver_cf(gr_feval_dd *tuner, int osr) for (i = 0; i < TRAIN_SEQ_NUM; i++) { gmsk_mapper(train_seq[i], N_TRAIN_BITS, d_norm_training_seq[i], gr_complex(1.0, 0.0)); } - + /* Initialize GSM Stack */ GS_new(&d_gs_ctx); //TODO: remove it! it'a not right place for a decoder } @@ -218,10 +219,16 @@ gsm_receiver_cf::general_work(int noutput_items, detect_burst(input, &channel_imp_resp[0], burst_start, output_binary); //MLSE detection of bits if (decode_sch(&output_binary[3], &t1, &t2, &t3, &d_ncc, &d_bcc) == 0) { //and decode SCH data // d_burst_nr.set(t1, t2, t3, 0); //but only to check if burst_start value is correct + d_failed_sch = 0; DCOUT("bcc: " << d_bcc << " ncc: " << d_ncc << " t1: " << t1 << " t2: " << t2 << " t3: " << t3); offset = burst_start - floor((GUARD_PERIOD) * d_OSR); //compute offset from burst_start - burst should start after a guard period DCOUT(offset); to_consume += offset; //adjust with offset number of samples to be consumed + } else { + d_failed_sch++; + if(d_failed_sch >= MAX_SCH_ERRORS){ + d_state = next_fcch_search; + } } } break; @@ -680,6 +687,5 @@ int gsm_receiver_cf::get_norm_chan_imp_resp(const gr_complex *input, gr_complex //std::cout << " burst_start: " << burst_start << " center: " << ((float)(search_start_pos + strongest_window_nr + chan_imp_resp_center)) / d_OSR << " stronegest window nr: " << strongest_window_nr << "\n"; return burst_start; - } diff --git a/src/lib/gsm_receiver_cf.h b/src/lib/gsm_receiver_cf.h index af13618..c37813a 100644 --- a/src/lib/gsm_receiver_cf.h +++ b/src/lib/gsm_receiver_cf.h @@ -96,6 +96,8 @@ class gsm_receiver_cf : public gr_block channel_configuration d_channel_conf; ///< mapping of burst_counter to burst_type //@} + unsigned d_failed_sch; ///< number of subsequent erroneous SCH bursts + // GSM Stack GS_CTX d_gs_ctx;//TODO: remove it! it'a not right place for a decoder diff --git a/src/python/gsm_findfcch_usrp.py b/src/python/gsm_findfcch_usrp.py deleted file mode 100755 index 7bf81f3..0000000 --- a/src/python/gsm_findfcch_usrp.py +++ /dev/null @@ -1,122 +0,0 @@ -#!/usr/bin/env python -#!/usr/bin/env python - -from gnuradio import gr, gru, blks2 -from gnuradio import usrp -#from gnuradio import gsm -from gnuradio.eng_option import eng_option -from optparse import OptionParser -from os import sys -#""" -for extdir in ['../../debug/src/lib','../../debug/src/lib/.libs']: - if extdir not in sys.path: - sys.path.append(extdir) -import gsm -#""" -def pick_subdevice(u): - if u.db[0][0].dbid() >= 0: - return (0, 0) - if u.db[1][0].dbid() >= 0: - return (1, 0) - return (0, 0) - -class gsm_receiver_first_blood(gr.top_block): - def __init__(self): - gr.top_block.__init__(self) - ( self.options, self.args) = self._przetworz_opcje() - self._ustaw_taktowanie() - self.zrodlo = self._ustaw_zrodlo() - self.filtr = self._ustaw_filtr() - self.interpolator = self._ustaw_interpolator() - self.odbiornik = self._ustaw_odbiornik() - self.konwerter = self._ustaw_konwerter() - self.ujscie = self._ustaw_ujscie() - - self.connect(self.zrodlo, self.filtr, self.interpolator, self.odbiornik, self.konwerter, self.ujscie) -# self.connect(self.zrodlo, self.ujscie) - - def _ustaw_ujscie(self): - nazwa_pliku_wy = self.options.outputfile - ujscie = gr.file_sink(gr.sizeof_float, nazwa_pliku_wy) - return ujscie - - def _ustaw_zrodlo(self): - options = self.options - fusb_block_size = gr.prefs().get_long('fusb', 'block_size', 4096) - fusb_nblocks = gr.prefs().get_long('fusb', 'nblocks', 16) - self.usrp = usrp.source_c(decim_rate=options.decim, fusb_block_size=fusb_block_size, fusb_nblocks=fusb_nblocks) - - if options.rx_subdev_spec is None: - options.rx_subdev_spec = pick_subdevice(self.usrp) - - self.usrp.set_mux(usrp.determine_rx_mux_value(self.usrp, options.rx_subdev_spec)) - # determine the daughterboard subdevice - self.subdev = usrp.selected_subdev(self.usrp, options.rx_subdev_spec) - input_rate = self.usrp.adc_freq() / self.usrp.decim_rate() - - # set initial values - if options.gain is None: - # if no gain was specified, use the mid-point in dB - g = self.subdev.gain_range() - options.gain = float(g[0]+g[1])/2 - - r = self.usrp.tune(0, self.subdev, options.freq) - self.subdev.set_gain(options.gain) - return self.usrp - - def _ustaw_taktowanie(self): - options = self.options - clock_rate = 64e6 - self.clock_rate = clock_rate - self.input_rate = clock_rate / options.decim - self.gsm_symb_rate = 1625000.0 / 6.0 - self.sps = self.input_rate / self.gsm_symb_rate - - def _ustaw_filtr(self): - filter_cutoff = 145e3 - filter_t_width = 10e3 - offset = 0 - print "input_rate:", self.input_rate, "sample rate:", self.sps, " filter_cutoff:", filter_cutoff, " filter_t_width:", filter_t_width - filter_taps = gr.firdes.low_pass(1.0, self.input_rate, filter_cutoff, filter_t_width, gr.firdes.WIN_HAMMING) - filtr = gr.freq_xlating_fir_filter_ccf(1, filter_taps, offset, self.input_rate) - return filtr - - def _ustaw_konwerter(self): - v2s = gr.vector_to_stream(gr.sizeof_float, 142) - return v2s - - def _ustaw_interpolator(self): - interpolator = gr.fractional_interpolator_cc(0, self.sps) - return interpolator - - def _ustaw_odbiornik(self): - odbiornik = gsm.receiver_cf(1) - return odbiornik - - def _przetworz_opcje(self): - parser = OptionParser(option_class=eng_option) - parser.add_option("-d", "--decim", type="int", default=128, - help="Set USRP decimation rate to DECIM [default=%default]") - parser.add_option("-I", "--inputfile", type="string", default="cfile", - help="Input filename") - parser.add_option("-O", "--outputfile", type="string", default="cfile2.out", - help="Output filename") - parser.add_option("-R", "--rx-subdev-spec", type="subdev", default=None, - help="Select USRP Rx side A or B (default=first one with a daughterboard)") - parser.add_option("-f", "--freq", type="eng_float", default="950.4M", - help="set frequency to FREQ", metavar="FREQ") - parser.add_option("-g", "--gain", type="eng_float", default=None, - help="Set gain in dB (default is midpoint)") - (options, args) = parser.parse_args () - return (options, args) - -def main(): - try: - gsm_receiver_first_blood().run() - except KeyboardInterrupt: - pass - -if __name__ == '__main__': - main() - - |