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Beta version of notch input filter

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Beta version of general_work method implemented
This commit is contained in:
Antonio Ramos 2017-06-20 18:13:52 +02:00
parent cf516566d6
commit 7fba751a49
4 changed files with 95 additions and 33 deletions
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14
src/algorithms/input_filter/adapters/notch_filter.cc
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@ -37,7 +37,7 @@
#include <gnuradio/blocks/file_sink.h>
#include <glog/logging.h>
#include "configuration_interface.h"
#include "notch_cc.cc"
#include "notch_cc.h"
using google::LogMessage;
@ -47,12 +47,12 @@ NotchFilter::NotchFilter(ConfigurationInterface* configuration, std::string role
out_streams_(out_streams)
{
size_t item_size_;
double pfa;
double default_pfa = 0.001;
double p_c_factor;
double default_p_c_factor = 0.9;
unsigned int length_;
unsigned int default_length_ = 5;
float pfa;
float default_pfa = 0.001;
float p_c_factor;
float default_p_c_factor = 0.9;
int length_;
int default_length_ = 5;
std::string default_item_type = "gr_complex";
std::string default_dump_file = "./data/input_filter.dat";
item_type_ = configuration->property(role + ".item_type", default_item_type);

3
src/algorithms/input_filter/adapters/notch_filter.h
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@ -37,6 +37,7 @@
#include <vector>
#include <gnuradio/blocks/file_sink.h>
#include "gnss_block_interface.h"
#include "notch_cc.h"
class ConfigurationInterface;
@ -77,7 +78,7 @@ private:
unsigned int in_streams_;
unsigned int out_streams_;
gr::blocks::file_sink::sptr file_sink_;
gr::block_sptr notch_filter_;
notch_sptr notch_filter_;
};
#endif //GNSS_SDR_NOTCH_FILTER_H_

75
src/algorithms/input_filter/gnuradio_blocks/notch_cc.cc
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@ -32,27 +32,32 @@
#include <boost/math/distributions/chi_squared.hpp>
#include <cmath>
#include <complex>
#include <gnuradio/block.h>
#include <gnuradio/io_signature.h>
#include <volk/volk.h>
notch_sptr make_notch_filter(double pfa, double p_c_factor,
unsigned int length_)
notch_sptr make_notch_filter(float pfa, float p_c_factor,
int length_)
{
return notch_sptr(new Notch(pfa, p_c_factor, length_));
}
Notch::Notch(double pfa, double p_c_factor, unsigned int length_) : gr::block("Notch",
Notch::Notch(float pfa, float p_c_factor, int length_) : gr::block("Notch",
gr::io_signature::make (1, 1, sizeof(gr_complex)),
gr::io_signature::make (1, 1, sizeof(gr_complex)))
{
const int alignment_multiple = volk_get_alignment() / sizeof(gr_complex);
set_alignment(std::max(1, alignment_multiple));
this->pfa = pfa;
this->noise_pow_est = 0.0;
noise_pow_est = 0.0;
this->p_c_factor = p_c_factor;
this->length_ = length_;
filter_state_ = 0;
filter_state_ = false;
n_deg_fred = 2 * length_;
n_segments_est = 5;
n_segments = 0;
z_0 = gr_complex(0 , 0);
thres_ =
boost::math::chi_squared_distribution<float> my_dist_(n_deg_fred);
thres_ = boost::math::quantile(boost::math::complement(my_dist_, pfa));
}
@ -60,5 +65,59 @@ Notch::Notch(double pfa, double p_c_factor, unsigned int length_) : gr::block("N
int Notch::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)
{
gr_complex * in = (gr_complex *) input_items[0];
gr_complex *out = (gr_complex *) output_items[0];
gr_complex * paux;
int samples_proc = 0;
int aux = 0;
gr_complex magnitude;
float sig2 = 0.0;
float* angle_;
gr_complex * c_samples;
c_samples = static_cast<gr_complex *>(volk_malloc(length_ * sizeof(gr_complex), volk_get_alignment()));
angle_ = static_cast<float *>(volk_malloc(length_ * sizeof(float), volk_get_alignment()));
while(((samples_proc + length_) < noutput_items) && (n_segments < n_segments_est))
{
volk_32fc_x2_conjugate_dot_prod_32fc(&magnitude, in, in, length_);
sig2 = magnitude.real() / ((float) n_deg_fred);
noise_pow_est = (((float) n_segments) * noise_pow_est + sig2) / ((float)(n_segments + 1));
samples_proc = samples_proc + length_;
n_segments++;
memcpy(out, in, sizeof(gr_complex)*length_);
in = (gr_complex *) input_items[samples_proc];
out = (gr_complex *) output_items[samples_proc];
}
while((samples_proc + length_) < noutput_items)
{
volk_32fc_x2_conjugate_dot_prod_32fc(&magnitude, in, in, length_);
if( (magnitude.real() / noise_pow_est) > thres_)
{
filter_state_ = true;
paux = (gr_complex *) input_items[samples_proc-1];
volk_32fc_x2_multiply_conjugate_32fc(c_samples, in, paux, length_);
volk_32fc_s32f_atan2_32f(angle_, c_samples, (float)1.0, length_);
for(aux = 0; aux < length_; aux++)
{
z_0 = std::exp(gr_complex(0,1) *angle_[aux]);
out[samples_proc] = in[samples_proc] - z_0 * in[samples_proc - 1]
+ gr_complex(p_c_factor,0) * z_0 * out[samples_proc -1];
samples_proc++;
in = (gr_complex *) input_items[samples_proc];
out = (gr_complex *) output_items[samples_proc];
}
}
else
{
filter_state_ = false;
samples_proc = samples_proc + length_;
memcpy(out, in, sizeof(gr_complex)*length_);
in = (gr_complex *) input_items[samples_proc];
out = (gr_complex *) output_items[samples_proc];
}
}
volk_free(c_samples);
volk_free(angle_);
consume_each(samples_proc);
return samples_proc;
}

36
src/algorithms/input_filter/gnuradio_blocks/notch_cc.h
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@ -38,37 +38,39 @@ class Notch;
typedef boost::shared_ptr<Notch> notch_sptr;
notch_sptr make_notch_filter(double pfa, double p_c_factor,
unsigned int length_);
notch_sptr make_notch_filter(float pfa, float p_c_factor,
int length_);
/*!
* \brief This class implements a real-time software-defined multi state notch filter
*/
class Notch: public gr::block
class Notch : public gr::block
{
private:
friend notch_sptr make_notch_filter(double pfa, double p_c_factor,
unsigned int length_);
double pfa;
double noise_pow_est;
double p_c_factor;
double thres_;
unsigned int length_;
unsigned int n_deg_fred;
unsigned int filter_state_;
float pfa;
float noise_pow_est;
float p_c_factor;
float thres_;
int length_;
int n_segments_est;
int n_segments;
int n_deg_fred;
bool filter_state_;
gr_complex z_0;
public:
Notch(double pfa, double p_c_factor, unsigned int length_);
//friend notch_sptr make_notch_filter(float pfa, float p_c_factor,
// int length_);
~Notch();
int work (int noutput_items, gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items);
Notch(float pfa, float p_c_factor, int length_);
int general_work (int noutput_items, gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items);
};
#endif //GNSS_SDR_NOTCH_H_