Improved Pulse Blanking Filter

Number of signal segments for estimating the noise power is passed now as a parameter in the configuration file

src/algorithms/input_filter/adapters/pulse_blanking_filter.cc

@@ -42,7 +42,6 @@ PulseBlankingFilter::PulseBlankingFilter(ConfigurationInterface* configuration,
                         out_streams_(out_streams)
 {
     size_t item_size;
-
     std::string default_input_item_type = "gr_complex";
     std::string default_output_item_type = "gr_complex";
     std::string default_dump_filename = "../data/input_filter.dat";
@@ -53,15 +52,19 @@ PulseBlankingFilter::PulseBlankingFilter(ConfigurationInterface* configuration,
     output_item_type_ = config_->property(role_ + ".output_item_type", default_output_item_type);
     dump_ = config_->property(role_ + ".dump", false);
     dump_filename_ = config_->property(role_ + ".dump_filename", default_dump_filename);
-    float default_pfa_ = 0.001;
+    float default_pfa_ = 0.01;
     float pfa = config_->property(role_ + ".pfa", default_pfa_);
-    int default_length_ = 32;
+    int default_length_ = 16;
     int length_ = config_->property(role_ + ".length", default_length_);
+    int default_n_segments_est = 25000;
+    int n_segments_est = config_->property(role_ + ".segments_estimation", default_n_segments_est);
+    int default_n_segments_reset = 500000;
+    int n_segments_reset = config_->property(role_ + ".segments_reset", default_n_segments_reset);
     if (input_item_type_.compare("gr_complex") == 0)
         {
             item_size = sizeof(gr_complex); //output
             input_size_ = sizeof(gr_complex); //input
-            pulse_blanking_cc_ = make_pulse_blanking_cc(pfa, length_);
+            pulse_blanking_cc_ = make_pulse_blanking_cc(pfa, length_, n_segments_est, n_segments_reset);
         }
     else
         {

src/algorithms/input_filter/adapters/pulse_blanking_filter.h

@@ -39,9 +39,6 @@
 
 class ConfigurationInterface;
 
-/*!
- * \brief TODO
- */
 class PulseBlankingFilter: public GNSSBlockInterface
 {
 public:

src/algorithms/input_filter/gnuradio_blocks/pulse_blanking_cc.cc

@@ -34,15 +34,19 @@
 #include <complex>
 #include <gnuradio/io_signature.h>
 #include <volk/volk.h>
+#include <glog/logging.h>
 
-pulse_blanking_cc_sptr make_pulse_blanking_cc(float pfa, int length_)
+using google::LogMessage;
+
+pulse_blanking_cc_sptr make_pulse_blanking_cc(float pfa, int length_, 
+                                              int n_segments_est, int n_segments_reset)
 {
-    return pulse_blanking_cc_sptr(new pulse_blanking_cc(pfa, length_));
+    return pulse_blanking_cc_sptr(new pulse_blanking_cc(pfa, length_, n_segments_est, n_segments_reset));
 }
 
 
 
-pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_) : gr::block("pulse_blanking_cc",
+pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_, int n_segments_est, int n_segments_reset) : gr::block("pulse_blanking_cc",
                         gr::io_signature::make (1, 1, sizeof(gr_complex)),
                         gr::io_signature::make (1, 1, sizeof(gr_complex)))
 {
@@ -53,8 +57,8 @@ pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_) : gr::block("pulse_
     set_output_multiple(length_);
     last_filtered = false;
     n_segments = 0;
-    n_segments_est = 8;
+    this->n_segments_est = n_segments_est;
-    n_segments_reset = 10000;
+    this->n_segments_reset = n_segments_reset;
     noise_power_estimation = 0.0;
     n_deg_fred = 2*length_;
     boost::math::chi_squared_distribution<float> my_dist_(n_deg_fred);
@@ -64,13 +68,13 @@ pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_) : gr::block("pulse_
     for (int aux = 0; aux < length_; aux++)
     {
         zeros_[aux] = gr_complex(0, 0);
-    }
+    }    
 }
 
 pulse_blanking_cc::~pulse_blanking_cc()
 {
     volk_free(zeros_);
-    volk_free(magnitude);
+    volk_free(magnitude);    
 }
 
 int pulse_blanking_cc::general_work (int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
@@ -87,7 +91,7 @@ int pulse_blanking_cc::general_work (int noutput_items __attribute__((unused)),
         if((n_segments < n_segments_est) && (last_filtered == false))
         {
             noise_power_estimation = (((float) n_segments) * noise_power_estimation + segment_energy / ((float)n_deg_fred)) / ((float)(n_segments + 1));
-            memcpy(out, in, sizeof(gr_complex)*length_);
+            memcpy(out, in, sizeof(gr_complex)*length_);            
         }
         else
         {

src/algorithms/input_filter/gnuradio_blocks/pulse_blanking_cc.h

@@ -38,12 +38,13 @@ class pulse_blanking_cc;
 
 typedef boost::shared_ptr<pulse_blanking_cc> pulse_blanking_cc_sptr;
 
-pulse_blanking_cc_sptr make_pulse_blanking_cc(float pfa, int length_);
+pulse_blanking_cc_sptr make_pulse_blanking_cc(float pfa, int length_, int n_segments_est, int n_segments_reset);
 
 
 class pulse_blanking_cc : public gr::block
 {
 private:
+    
     int length_;
     int n_segments;
     int n_segments_est;
@@ -55,13 +56,16 @@ private:
     float pfa;
     float* magnitude;
     gr_complex* zeros_;
+    
 public:
-    pulse_blanking_cc(float pfa, int length_);
+    
+    pulse_blanking_cc(float pfa, int length_, int n_segments_est, int n_segments_reset);
     
     ~pulse_blanking_cc();
 
     int general_work (int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
             gr_vector_const_void_star &input_items, gr_vector_void_star &output_items);
+    
 };
 
 #endif