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Improving real-time performances of input filters

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Pulse blanking and Notch filters improved
This commit is contained in:
Antonio Ramos 2017-08-21 13:11:18 +02:00
parent 1e753e5f54
commit e1dc9f5aac
5 changed files with 56 additions and 66 deletions
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8
src/algorithms/input_filter/adapters/pulse_blanking_filter.cc
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@ -52,13 +52,13 @@ 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_ = 0.01;
float default_pfa_ = 0.04;
float pfa = config_->property(role_ + ".pfa", default_pfa_);
int default_length_ = 16;
int default_length_ = 32;
int length_ = config_->property(role_ + ".length", default_length_);
int default_n_segments_est = 25000;
int default_n_segments_est = 12500;
int n_segments_est = config_->property(role_ + ".segments_estimation", default_n_segments_est);
int default_n_segments_reset = 500000;
int default_n_segments_reset = 5000000;
int n_segments_reset = config_->property(role_ + ".segments_reset", default_n_segments_reset);
if (input_item_type_.compare("gr_complex") == 0)
{

94
src/algorithms/input_filter/gnuradio_blocks/notch_cc.cc
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@ -84,75 +84,61 @@ Notch::~Notch()
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)
{
int index_in = 1;
int index_out = 0;
int aux = 0;
float sig2dB = 0.0;
float sig2lin = 0.0;
lv_32fc_t dot_prod_;
gr_complex* in = (gr_complex *) input_items[0];
gr_complex* out = (gr_complex *) output_items[0];
gr_complex* paux;
in++;
arma::cx_fvec signal_segment;
arma::cx_fvec signal_segment_fft;
while(((index_out + length_) < noutput_items) && (n_segments < n_segments_est) && (filter_state_ == false))
while((index_out + length_) < noutput_items)
{
signal_segment = arma::cx_fvec(in, length_, false, false);
signal_segment_fft = arma::fft(signal_segment);
volk_32fc_s32f_power_spectrum_32f(power_spect, signal_segment_fft.memptr(), 1.0, length_);
volk_32f_s32f_calc_spectral_noise_floor_32f(&sig2dB, power_spect, 15.0, length_);
sig2lin = std::pow(10.0, (sig2dB / 10.0)) / ((float) n_deg_fred);
noise_pow_est = (((float) n_segments) * noise_pow_est + sig2lin) / ((float)(n_segments + 1));
memcpy(out, in, sizeof(gr_complex) * length_);
if((n_segments < n_segments_est) && (filter_state_ == false))
{
signal_segment = arma::cx_fvec(in, length_, false, false);
signal_segment_fft = arma::fft(signal_segment);
volk_32fc_s32f_power_spectrum_32f(power_spect, signal_segment_fft.memptr(), 1.0, length_);
volk_32f_s32f_calc_spectral_noise_floor_32f(&sig2dB, power_spect, 15.0, length_);
sig2lin = std::pow(10.0, (sig2dB / 10.0)) / ((float) n_deg_fred);
noise_pow_est = (((float) n_segments) * noise_pow_est + sig2lin) / ((float)(n_segments + 1));
memcpy(out, in, sizeof(gr_complex) * length_);
}
else
{
volk_32fc_x2_conjugate_dot_prod_32fc(&dot_prod_, in, in, length_);
if( (lv_creal(dot_prod_) / noise_pow_est) > thres_)
{
if(filter_state_ == false)
{
filter_state_ = true;
last_out = gr_complex(0,0);
}
volk_32fc_x2_multiply_conjugate_32fc(c_samples, in, (in - 1), length_);
volk_32fc_s32f_atan2_32f(angle_, c_samples, ((float)1.0), length_);
for(int aux = 0; aux < length_; aux++)
{
z_0 = std::exp(gr_complex(0,1) * (*(angle_ + aux)));
*(out + aux) = *(in + aux) - z_0 * (*(in + aux - 1)) + p_c_factor * z_0 * last_out;
last_out = *(out + aux);
}
}
else
{
if (n_segments > n_segments_reset)
{
n_segments = 0;
}
filter_state_ = false;
memcpy(out, in, sizeof(gr_complex) * length_);
}
}
index_out += length_;
index_in += length_;
n_segments++;
in += length_;
out += length_;
}
while((index_out + length_) < noutput_items)
{
n_segments++;
volk_32fc_x2_conjugate_dot_prod_32fc(&dot_prod_, in, in, length_);
if( (lv_creal(dot_prod_) / noise_pow_est) > thres_)
{
if(filter_state_ == false)
{
filter_state_ = true;
last_out = gr_complex(0,0);
}
paux = in - 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 = (*in) - z_0 * (*(in - 1))
+ p_c_factor * z_0 * last_out;
last_out = *out;
index_out++;
index_in++;
in ++;
out ++;
}
}
else
{
if (n_segments > n_segments_reset)
{
n_segments = 0;
}
filter_state_ = false;
memcpy(out, in, sizeof(gr_complex) * length_);
index_out += length_;
index_in += length_;
in += length_;
out += length_;
}
}
consume_each(index_out);
return index_out;
}

12
src/algorithms/input_filter/gnuradio_blocks/pulse_blanking_cc.cc
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@ -44,8 +44,6 @@ pulse_blanking_cc_sptr make_pulse_blanking_cc(float pfa, int 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_, 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)))
@ -64,7 +62,6 @@ pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_, int n_segments_est,
boost::math::chi_squared_distribution<float> my_dist_(n_deg_fred);
thres_ = boost::math::quantile(boost::math::complement(my_dist_, pfa));
zeros_ = static_cast<gr_complex *>(volk_malloc(length_ * sizeof(gr_complex), volk_get_alignment()));
magnitude = static_cast<float *>(volk_malloc(length_ * sizeof(float), volk_get_alignment()));
for (int aux = 0; aux < length_; aux++)
{
zeros_[aux] = gr_complex(0, 0);
@ -73,8 +70,7 @@ pulse_blanking_cc::pulse_blanking_cc(float pfa, int length_, int n_segments_est,
pulse_blanking_cc::~pulse_blanking_cc()
{
volk_free(zeros_);
volk_free(magnitude);
volk_free(zeros_);
}
int pulse_blanking_cc::general_work (int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
@ -82,12 +78,13 @@ int pulse_blanking_cc::general_work (int noutput_items __attribute__((unused)),
{
gr_complex *in = (gr_complex *) input_items[0];
gr_complex *out = (gr_complex *) output_items[0];
float* magnitude = static_cast<float *>(volk_malloc(noutput_items * sizeof(float), volk_get_alignment()));
volk_32fc_magnitude_squared_32f(magnitude, in, noutput_items);
int sample_index = 0;
float segment_energy;
while((sample_index + length_) < noutput_items)
{
volk_32fc_magnitude_squared_32f(magnitude, in, length_);
volk_32f_accumulator_s32f(&segment_energy, magnitude, length_);
volk_32f_accumulator_s32f(&segment_energy, (magnitude + sample_index), length_);
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));
@ -115,6 +112,7 @@ int pulse_blanking_cc::general_work (int noutput_items __attribute__((unused)),
sample_index+=length_;
n_segments++;
}
volk_free(magnitude);
consume_each(sample_index);
return sample_index;
}

1
src/algorithms/input_filter/gnuradio_blocks/pulse_blanking_cc.h
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@ -54,7 +54,6 @@ private:
float noise_power_estimation;
float thres_;
float pfa;
float* magnitude;
gr_complex* zeros_;
public:

7
src/core/receiver/gnss_block_factory.cc
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@ -66,6 +66,7 @@
#include "beamformer_filter.h"
#include "pulse_blanking_filter.h"
#include "notch_filter.h"
#include "notch_filter_lite.h"
#include "gps_l1_ca_pcps_acquisition.h"
#include "gps_l2_m_pcps_acquisition.h"
#include "gps_l1_ca_pcps_multithread_acquisition.h"
@ -889,6 +890,12 @@ std::unique_ptr<GNSSBlockInterface> GNSSBlockFactory::GetBlock(
out_streams));
block = std::move(block_);
}
else if (implementation.compare("Notch_Filter_Lite") == 0)
{
std::unique_ptr<GNSSBlockInterface> block_(new NotchFilterLite(configuration.get(), role, in_streams,
out_streams));
block = std::move(block_);
}
// RESAMPLER -------------------------------------------------------------------