diff options
Diffstat (limited to 'src/lib/gsm_receiver_cf.cc')
| -rw-r--r-- | src/lib/gsm_receiver_cf.cc | 118 |
1 files changed, 60 insertions, 58 deletions
diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc index 5453253..e4d2696 100644 --- a/src/lib/gsm_receiver_cf.cc +++ b/src/lib/gsm_receiver_cf.cc @@ -36,7 +36,7 @@ #include <sch.h> #define FCCH_BUFFER_SIZE (FCCH_HITS_NEEDED) -#define SYNC_SEARCH_RANGE 40 +#define SYNC_SEARCH_RANGE 60 //TODO !! - move this methods to some else place @@ -142,60 +142,62 @@ gsm_receiver_cf::general_work(int noutput_items, //in this state receiver is synchronized and it processes bursts according to burst type for given burst number case synchronized: { - gr_complex chan_imp_resp[100];//!! - burst_type b_type = d_channel_conf.get_burst_type(d_burst_nr); - int burst_start; - int offset = 0; - int to_consume = 0; - unsigned char output_binary[BURST_SIZE]; - - switch (b_type) { - case fcch_burst: { - int ii; - int first_sample = (GUARD_BITS+TAIL_BITS)*d_OSR; - int last_sample = first_sample+USEFUL_BITS*d_OSR; - double phase_sum = 0; - for(ii = first_sample; ii < last_sample; ii++){ - phase_sum += compute_phase_diff(in[ii], in[ii-1]) - (M_PI / 2) / d_OSR; - } - std::cout << "freq_offset: " << d_freq_offset << "\n"; - - double freq_offset = compute_freq_offset(phase_sum, USEFUL_BITS-TAIL_BITS); - d_freq_offset -= freq_offset; - set_frequency(d_freq_offset); - std::cout << "freq_offset: " << d_freq_offset << "\n"; - } - break; - case sch_burst: { - int t1, t2, t3, d_ncc, d_bcc; - burst_start = get_sch_chan_imp_resp(in, chan_imp_resp); - detect_burst(in, chan_imp_resp, burst_start, output_binary); - if(decode_sch(&output_binary[3], &t1, &t2, &t3, &d_ncc, &d_bcc) == 0){ -// d_burst_nr.set(t1, t2, t3, 0); - printf("bcc: %d, ncc: %d, t1: %d, t2: %d, t3: %d\n", d_bcc, d_ncc, t1, t2, t3); - offset = burst_start - GUARD_BITS * d_OSR; - to_consume += offset; - } - std::cout << offset << std::endl; - } - break; - case normal_burst: - - break; + gr_complex chan_imp_resp[100];//!! + burst_type b_type = d_channel_conf.get_burst_type(d_burst_nr); + int burst_start; + int offset = 0; + int to_consume = 0; + unsigned char output_binary[BURST_SIZE]; + + switch (b_type) { + case fcch_burst: { + int ii; + int first_sample = (GUARD_BITS+TAIL_BITS) *d_OSR; + int last_sample = first_sample+USEFUL_BITS*d_OSR; + double phase_sum = 0; + for (ii = first_sample; ii < last_sample; ii++) { + double phase_diff = compute_phase_diff(in[ii], in[ii-1]) * d_OSR; +// std::cout << "phase_diff: " << phase_diff << "\n"; + phase_sum += phase_diff; + } + //std::cout << "phase_sum: " << phase_sum << "\n"; - case rach_burst: - break; - case dummy: - break; - case empty: - break; +// double freq_offset = compute_freq_offset(phase_sum, USEFUL_BITS-TAIL_BITS); +// d_freq_offset -= freq_offset; +// set_frequency(d_freq_offset); +// std::cout << "freq_offset: " << d_freq_offset << "\n"; } + break; + case sch_burst: { + int t1, t2, t3, d_ncc, d_bcc; + burst_start = get_sch_chan_imp_resp(in, chan_imp_resp); + detect_burst(in, chan_imp_resp, burst_start, output_binary); + if (decode_sch(&output_binary[3], &t1, &t2, &t3, &d_ncc, &d_bcc) == 0) { +// d_burst_nr.set(t1, t2, t3, 0); + printf("bcc: %d, ncc: %d, t1: %d, t2: %d, t3: %d\n", d_bcc, d_ncc, t1, t2, t3); + offset = burst_start - GUARD_BITS * d_OSR; + to_consume += offset; + } + std::cout << offset << std::endl; + } + break; + case normal_burst: - d_burst_nr++; - to_consume += floor(TS_BITS * d_OSR); - consume_each(to_consume); + break; + + case rach_burst: + break; + case dummy: + break; + case empty: + break; } - break; + + d_burst_nr++; + to_consume += floor(TS_BITS * d_OSR); + consume_each(to_consume); + } + break; } return produced_out; @@ -277,8 +279,8 @@ bool gsm_receiver_cf::find_fcch_burst(const gr_complex *in, const int nitems) //find difference between minimal and maximal element in the buffer //for FCCH this value should be low //this part is searching for a region where this value is lowest - min_phase_diff = *(min_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); - max_phase_diff = *(max_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); + min_phase_diff = * (min_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); + max_phase_diff = * (max_element(phase_diff_buffer.begin(), phase_diff_buffer.end())); if (lowest_max_min_diff > max_phase_diff - min_phase_diff) { lowest_max_min_diff = max_phase_diff - min_phase_diff; @@ -343,7 +345,7 @@ double gsm_receiver_cf::compute_freq_offset(double best_sum, unsigned denominato // d_x2_temp += freq_offset * freq_offset; // d_mean = d_x_temp / d_fcch_count; - DCOUT("freq_offset: " << freq_offset );//" best_sum: " << best_sum + DCOUT("freq_offset: " << freq_offset); //" best_sum: " << best_sum // DCOUT("wariance: " << sqrt((d_x2_temp / d_fcch_count - d_mean * d_mean)) << " fcch_count:" << d_fcch_count << " d_mean: " << d_mean); return freq_offset; @@ -443,7 +445,7 @@ int gsm_receiver_cf::get_sch_chan_imp_resp(const gr_complex *in, gr_complex * ch float max_correlation = 0; float energy = 0; - for (int ii = SYNC_POS * d_OSR; ii < (SYNC_POS + SYNC_SEARCH_RANGE)*d_OSR; ii++) { + for (int ii = SYNC_POS * d_OSR; ii < (SYNC_POS + SYNC_SEARCH_RANGE) *d_OSR; ii++) { gr_complex correlation = correlate_sequence(&d_sch_training_seq[5], &in[ii], N_SYNC_BITS - 10); correlation_buffer.push_back(correlation); power_buffer.push_back(pow(abs(correlation), 2)); @@ -456,7 +458,7 @@ int gsm_receiver_cf::get_sch_chan_imp_resp(const gr_complex *in, gr_complex * ch vector_float::iterator iter_ii = iter; energy = 0; - for (int ii = 0; ii < (d_chan_imp_length)*d_OSR; ii++, iter_ii++) { + for (int ii = 0; ii < (d_chan_imp_length) *d_OSR; ii++, iter_ii++) { if (iter_ii == power_buffer.end()) { loop_end = true; break; @@ -474,7 +476,7 @@ int gsm_receiver_cf::get_sch_chan_imp_resp(const gr_complex *in, gr_complex * ch d_channel_imp_resp.clear(); max_correlation = 0; - for (int ii = 0; ii < (d_chan_imp_length)*d_OSR; ii++) { + for (int ii = 0; ii < (d_chan_imp_length) *d_OSR; ii++) { gr_complex correlation = correlation_buffer[strongest_window_nr + ii]; if (abs(correlation) > max_correlation) { chan_imp_resp_center = ii; @@ -589,6 +591,6 @@ inline void gsm_receiver_cf::mafi(const gr_complex * input, int input_length, gr output[n] += input[a+ii] * filter[ii]; //!!conj ii++; } - output[n] = output[n] * gr_complex(0, -1);//!!this shouldn't be here + output[n] = output[n] * gr_complex(0, -1); //!!this shouldn't be here } } |