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-rw-r--r--src/lib/gsm_receiver_cf.cc118
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
}
}
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