diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Makefile.am | 2 | ||||
| -rw-r--r-- | src/lib/gsm_receiver_cf.cc | 141 | ||||
| -rw-r--r-- | src/lib/gsm_receiver_cf.h | 19 |
3 files changed, 98 insertions, 64 deletions
diff --git a/src/Makefile.am b/src/Makefile.am index 3ff9849..79cfa3e 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -19,5 +19,5 @@ # Boston, MA 02110-1301, USA. # -SUBDIRS = lib +SUBDIRS = lib python diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc index e478c66..206bd5e 100644 --- a/src/lib/gsm_receiver_cf.cc +++ b/src/lib/gsm_receiver_cf.cc @@ -1,19 +1,19 @@ /* -*- c++ -*- */ /* * Copyright 2004 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, @@ -26,94 +26,123 @@ #include <gsm_receiver_cf.h> #include <gr_io_signature.h> +#include <gr_math.h> +#include <gsm_constants.h> +#include <Assert.h> -gsm_receiver_cf_sptr -gsm_make_receiver_cf () + +gsm_receiver_cf_sptr +gsm_make_receiver_cf(int osr) { - return gsm_receiver_cf_sptr (new gsm_receiver_cf ()); + return gsm_receiver_cf_sptr(new gsm_receiver_cf(osr)); } -static const int MIN_IN = 1; // mininum number of input streams -static const int MAX_IN = 1; // maximum number of input streams -static const int MIN_OUT = 1; // minimum number of output streams -static const int MAX_OUT = 1; // maximum number of output streams +static const int MIN_IN = 1; // mininum number of input streams +static const int MAX_IN = 1; // maximum number of input streams +static const int MIN_OUT = 0; // minimum number of output streams +static const int MAX_OUT = 1; // maximum number of output streams /* * The private constructor */ -gsm_receiver_cf::gsm_receiver_cf () - : gr_block ("gsm_receiver", - gr_make_io_signature (MIN_IN, MAX_IN, sizeof (gr_complex)), - gr_make_io_signature (MIN_OUT, MAX_OUT, sizeof (float))) +gsm_receiver_cf::gsm_receiver_cf(int osr) + : gr_block("gsm_receiver", + gr_make_io_signature(MIN_IN, MAX_IN, sizeof(gr_complex)), + gr_make_io_signature(MIN_OUT, MAX_OUT, 142 * sizeof(float))), + d_counter(0) { } /* * Virtual destructor. */ -gsm_receiver_cf::~gsm_receiver_cf () +gsm_receiver_cf::~gsm_receiver_cf() +{ +} + +void gsm_receiver_cf::forecast(int noutput_items, gr_vector_int &ninput_items_required) { + ninput_items_required[0] = noutput_items * TS_BITS; //TODO include oversampling ratio here } -int -gsm_receiver_cf::general_work (int noutput_items, - gr_vector_int &ninput_items, - gr_vector_const_void_star &input_items, - gr_vector_void_star &output_items) +int +gsm_receiver_cf::general_work(int noutput_items, + gr_vector_int &ninput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) { - const float *in = (const float *) input_items[0]; + const gr_complex *in = (const gr_complex *) input_items[0]; float *out = (float *) output_items[0]; - for (int i = 0; i < noutput_items; i++){ - out[i] = in[i] * in[i]; - } +// DCOUT(ninput_items[0]); +// DCOUT(noutput_items); - consume_each (noutput_items); - return noutput_items; + d_return = 0; //! + int start_pos = find_fcch_burst(in, ninput_items[0]); + for (int i = 0; i < TS_BITS; i++) { + out[i] = d_phase_diff_buffer[i+start_pos-USEFUL_BITS]; + } + consume_each(start_pos); + d_counter += start_pos; + return d_return; } - -bool gsm_receiver_cf::get_fcch_burst() +int gsm_receiver_cf::find_fcch_burst(const gr_complex *in, const int nitems) { + for (int i = 0; (i < nitems - 1) && (i < BUFFER_SIZE); i++) { + gr_complex conjprod = in[i+1] * conj(in[i]); + float diff_angle = gr_fast_atan2f(imag(conjprod), real(conjprod)); + d_phase_diff_buffer[i] = diff_angle; + } + int hit_count = 0; int miss_count = 0; int start_pos = -1; -/* - for ( int i=0; i < BBUF_SIZE; i++ ) { - if ( d_burst_buffer[i] > 0 ) { - if ( ! hit_count++ ) - start_pos = i; - } else { - if ( hit_count >= FCCH_HITS_NEEDED ) { - break; - } else - if ( ++miss_count > FCCH_MAX_MISSES ) { - start_pos = -1; - hit_count = miss_count = 0; - } - } + + d_return = 0;//! + + for (int i = 0; ; i++) { + if (i > nitems - USEFUL_BITS - 1) { + start_pos = nitems - USEFUL_BITS - 1; + break; } - //Do we have a match? - if ( start_pos >= 0 ) { + if (d_phase_diff_buffer[i] > 0) { + if (! hit_count) { + start_pos = i+USEFUL_BITS; + } + hit_count++; + } else if (hit_count >= FCCH_HITS_NEEDED) { + DCOUT("znalezione fcch na pozycji" << d_counter+start_pos-USEFUL_BITS); + d_return = 1;//! + break; + } else if (++miss_count > FCCH_MAX_MISSES) { + start_pos = -1; + hit_count = miss_count = 0; + } + } + + /* + //Do we have a match? + if (start_pos >= 0) { //Is it within range? (we know it's long enough then too) - if ( start_pos < 2*MAX_CORR_DIST ) { - d_burst_start = start_pos; - d_bbuf_pos = 0; //load buffer from start - return FCCH; - - } else { - //TODO: don't shift a tiny amount - shift_burst( start_pos - MAX_CORR_DIST ); - } + if (start_pos < 2*MAX_CORR_DIST) { + d_burst_start = start_pos; + d_bbuf_pos = 0; //load buffer from start + return FCCH; + } else { + //TODO: don't shift a tiny amount + shift_burst(start_pos - MAX_CORR_DIST); + } } else { //Didn't find anything d_burst_start = MAX_CORR_DIST; d_bbuf_pos = 0; //load buffer from start } + */ + //DCOUT("start_pos: " << start_pos); - return UNKNOWN; -*/ + return start_pos; } diff --git a/src/lib/gsm_receiver_cf.h b/src/lib/gsm_receiver_cf.h index 7067fb2..5bc7617 100644 --- a/src/lib/gsm_receiver_cf.h +++ b/src/lib/gsm_receiver_cf.h @@ -25,6 +25,8 @@ #include <gr_block.h> #include <gr_complex.h> +#define BUFFER_SIZE 4096 + class gsm_receiver_cf; /* @@ -47,26 +49,29 @@ typedef boost::shared_ptr<gsm_receiver_cf> gsm_receiver_cf_sptr; * constructor is private. howto_make_square_ff is the public * interface for creating new instances. */ -gsm_receiver_cf_sptr gsm_make_receiver_cf(); +gsm_receiver_cf_sptr gsm_make_receiver_cf( int osr ); /*! * \brief Receives fcch * \ingroup block - * \sa + * \sa */ class gsm_receiver_cf : public gr_block { private: - friend gsm_receiver_cf_sptr gsm_make_receiver_cf(); - - gsm_receiver_cf(); - bool get_fcch_burst(); + int d_counter; + int d_return; + float d_phase_diff_buffer[BUFFER_SIZE]; + + friend gsm_receiver_cf_sptr gsm_make_receiver_cf( int osr ); + gsm_receiver_cf( int osr ); + int find_fcch_burst( const gr_complex *in, const int items ); public: ~gsm_receiver_cf(); - + void forecast( int noutput_items, gr_vector_int &ninput_items_required ); int general_work( int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, |