resampler causes that frequency estimate is getting lower for higher osr

2 files changed, 30 insertions, 14 deletions

diff --git a/src/lib/gsm_receiver_cf.cc b/src/lib/gsm_receiver_cf.cc
index 045c639..8e4670b 100644
--- a/src/lib/gsm_receiver_cf.cc
+++ b/src/lib/gsm_receiver_cf.cc
@@ -208,7 +208,7 @@ bool gsm_receiver_cf::find_fcch_burst(const gr_complex *in, const int nitems)
           fcch_search_state = init;
           //DCOUT("hit_count: " << hit_count << " miss_count: " << miss_count << " d_counter: " << d_counter);
           continue;
-        } else if ((miss_count >= FCCH_MAX_MISSES * d_OSR) && (hit_count > FCCH_HITS_NEEDED * d_OSR)) {
+        } else if (((miss_count >= FCCH_MAX_MISSES * d_OSR) && (hit_count > FCCH_HITS_NEEDED * d_OSR)) || (hit_count > 2 * FCCH_HITS_NEEDED * d_OSR)) {
           fcch_search_state = fcch_found;
           continue;
         } else if ((miss_count < FCCH_MAX_MISSES * d_OSR) && (hit_count > FCCH_HITS_NEEDED * d_OSR)) {
@@ -239,6 +239,7 @@ bool gsm_receiver_cf::find_fcch_burst(const gr_complex *in, const int nitems)
         }
 
         phase_diff = compute_phase_diff(in[sample_number], in[sample_number-1]);
+//        std::cout << phase_diff << "\n";
         phase_diff_buffer.push_back(phase_diff);
         fcch_search_state = found_something;
 
@@ -302,7 +303,7 @@ bool gsm_receiver_cf::find_sch_burst(const gr_complex *in, const int nitems , fl
   bool result = false;
   int sample_nr_near_sch_start = d_fcch_start_pos + (FRAME_BITS - SAFETY_MARGIN) * d_OSR;
   vector_complex correlation_buffer;
-  list_float power_buffer;
+  vector_float power_buffer;
   vector_float window_energy_buffer;
   int strongest_window_nr;
 
@@ -315,7 +316,7 @@ bool gsm_receiver_cf::find_sch_burst(const gr_complex *in, const int nitems , fl
   int chan_imp_length = 4;
   float energy = 0;
   bool loop_end = false;
-  list_float::iterator iter;
+  vector_float::iterator iter;
 
   while (!end) {
     switch (sch_search_state) {
@@ -350,34 +351,50 @@ bool gsm_receiver_cf::find_sch_burst(const gr_complex *in, const int nitems , fl
         }
 
         //compute window energies
+
+//         std::cout << "\nkorelacje wybrane do liczenia energii\n";
         iter = power_buffer.begin();
+        
         while (iter != power_buffer.end()) {
-          list_float::iterator iter_ii = iter;
+          vector_float::iterator iter_ii = iter;
           energy = 0;
 
-          for (int ii = 0; ii < chan_imp_length; ii++, iter_ii++) {
+          for (int ii = 0; ii < chan_imp_length; ii++) {
             if (iter_ii == power_buffer.end()) {
               loop_end = true;
               break;
             }
+//             std::cout << iter_ii - power_buffer.begin() << "\n";
             energy += (*iter_ii);
+            iter_ii = iter_ii+d_OSR;
           }
+//           std::cout <<  "\n";
 
           if (loop_end) {
             break;
           }
           iter++;
-//          std::cout << energy << "\n";
+//           std::cout << energy << "\n";
           window_energy_buffer.push_back(energy);
         }
 
         strongest_window_nr = max_element(window_energy_buffer.begin(), window_energy_buffer.end()) - window_energy_buffer.begin();
         d_channel_imp_resp.clear();
-        for (int ii = 0; ii < chan_imp_length; ii++) {
+       std::cout << "\nOdp impulsowa:\n";
+        for (int ii = 0; ii < chan_imp_length+1; ii++) {
           gr_complex correlation = correlation_buffer[strongest_window_nr + (ii * d_OSR)];
+         std::cout << correlation << "\n";
           d_channel_imp_resp.push_back(correlation);
         }
 
+        std::cout << "\nBurst:\n";
+
+        for (int ii = 0; ii < 156; ii++) {
+          gr_complex correlation = in[strongest_window_nr + (ii * d_OSR) - 42* d_OSR + SYNC_POS * d_OSR];
+         std::cout << correlation << "\n";
+          d_channel_imp_resp.push_back(correlation);
+        }
+        std::cout << "\n\n";
         DCOUT("strongest_window_nr: " << strongest_window_nr);
 
         sch_search_state = sch_found;
diff --git a/src/python/gsm_findfcch.py b/src/python/gsm_findfcch.py
index 7ab9c18..5f85dc2 100755
--- a/src/python/gsm_findfcch.py
+++ b/src/python/gsm_findfcch.py
@@ -16,12 +16,11 @@ class tune(gr.feval_dd):
     def __init__(self, top_block):
         gr.feval_dd.__init__(self)
         self.top_block = top_block
-        self.center_freq = 0
+        # self.center_freq = 0
     def eval(self, freq_offet):
-        self.center_freq = self.center_freq - freq_offet
-        self.top_block.set_frequency(self.center_freq)
-        return self.center_freq
-
+        # self.center_freq = self.center_freq - freq_offet
+        self.top_block.set_frequency(freq_offet)
+        return freq_offet
 
 class gsm_receiver_first_blood(gr.top_block):
     def __init__(self):
@@ -57,13 +56,13 @@ class gsm_receiver_first_blood(gr.top_block):
         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
+        self.sps = self.input_rate / self.gsm_symb_rate / self.options.osr
 
     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
+        #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