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Code Issues Releases Wiki Activity

Migrate pcps_acq_sc to new grid

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This commit is contained in:
Antonio Ramos 2018-02-06 13:11:15 +01:00
parent eb7cf3e7bb
commit 41712e4722
2 changed files with 205 additions and 306 deletions
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445
src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc
View File

@ -36,7 +36,8 @@
#include "pcps_acquisition_sc.h"
#include <sstream>
#include <boost/filesystem.hpp>
#include <cstring>
#include <matio.h>
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
#include <volk/volk.h>
@ -44,8 +45,6 @@
#include "GPS_L1_CA.h" //GPS_TWO_PI
#include "GLONASS_L1_CA.h" //GLONASS_TWO_PI
using google::LogMessage;
pcps_acquisition_sc_sptr pcps_make_acquisition_sc(
@ -88,7 +87,7 @@ pcps_acquisition_sc::pcps_acquisition_sc(
d_well_count = 0;
d_doppler_max = doppler_max;
d_fft_size = d_sampled_ms * d_samples_per_ms;
d_mag = 0;
d_mag = 0.0;
d_input_power = 0.0;
d_num_doppler_bins = 0;
d_bit_transition_flag = bit_transition_flag;
@ -98,9 +97,6 @@ pcps_acquisition_sc::pcps_acquisition_sc(
d_code_phase = 0;
d_test_statistics = 0.0;
d_channel = 0;
d_doppler_freq = 0.0;
//set_relative_rate( 1.0/d_fft_size );
// COD:
// Experimenting with the overlap/save technique for handling bit trannsitions
@ -133,15 +129,12 @@ pcps_acquisition_sc::pcps_acquisition_sc(
// For dumping samples into a file
d_dump = dump;
d_dump_filename = dump_filename;
d_gnss_synchro = 0;
d_grid_doppler_wipeoffs = 0;
d_done = false;
d_blocking = blocking;
d_new_data_available = false;
d_worker_active = false;
d_data_buffer = static_cast<lv_16sc_t*>(volk_gnsssdr_malloc(d_fft_size * sizeof(lv_16sc_t), volk_gnsssdr_get_alignment()));
grid_ = arma::fmat();
}
@ -155,32 +148,12 @@ pcps_acquisition_sc::~pcps_acquisition_sc()
}
delete[] d_grid_doppler_wipeoffs;
}
volk_gnsssdr_free(d_fft_codes);
volk_gnsssdr_free(d_magnitude);
volk_gnsssdr_free(d_in_32fc);
delete d_ifft;
delete d_fft_if;
if (d_dump)
{
d_dump_file.close();
}
// Let the worker thread know that we are done and then wait to join
if( d_worker_thread.joinable() )
{
{
std::lock_guard<std::mutex> lk( d_mutex );
d_done = true;
d_cond.notify_one();
}
d_worker_thread.join();
}
volk_gnsssdr_free( d_data_buffer );
volk_gnsssdr_free(d_data_buffer);
}
@ -263,10 +236,13 @@ void pcps_acquisition_sc::init()
int doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
update_local_carrier(d_grid_doppler_wipeoffs[doppler_index], d_fft_size, d_freq + doppler);
}
d_new_data_available = false;
d_done = false;
d_worker_active = false;
if(d_dump)
{
unsigned int effective_fft_size = (d_bit_transition_flag ? (d_fft_size / 2) : d_fft_size);
grid_ = arma::fmat(effective_fft_size, d_num_doppler_bins, arma::fill::zeros);
}
}
void pcps_acquisition_sc::update_grid_doppler_wipeoffs()
@ -296,6 +272,7 @@ void pcps_acquisition_sc::set_state(int state)
d_mag = 0.0;
d_input_power = 0.0;
d_test_statistics = 0.0;
d_active = true;
}
else if (d_state == 0)
{}
@ -342,7 +319,7 @@ void pcps_acquisition_sc::send_negative_acquisition()
}
int pcps_acquisition_sc::general_work(int noutput_items,
int pcps_acquisition_sc::general_work(int noutput_items __attribute__((unused)),
gr_vector_int &ninput_items, gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items __attribute__((unused)))
{
@ -357,213 +334,212 @@ int pcps_acquisition_sc::general_work(int noutput_items,
* 6. Declare positive or negative acquisition using a message port
*/
switch (d_state)
gr::thread::scoped_lock lk(d_setlock);
if(!d_active || d_worker_active)
{
d_sample_counter += d_fft_size * ninput_items[0];
consume_each(ninput_items[0]);
return 0;
}
switch(d_state)
{
case 0:
{
if (d_active)
{
//restart acquisition variables
d_gnss_synchro->Acq_delay_samples = 0.0;
d_gnss_synchro->Acq_doppler_hz = 0.0;
d_gnss_synchro->Acq_samplestamp_samples = 0;
d_well_count = 0;
d_mag = 0.0;
d_input_power = 0.0;
d_test_statistics = 0.0;
d_state = 1;
}
//restart acquisition variables
d_gnss_synchro->Acq_delay_samples = 0.0;
d_gnss_synchro->Acq_doppler_hz = 0.0;
d_gnss_synchro->Acq_samplestamp_samples = 0;
d_well_count = 0;
d_mag = 0.0;
d_input_power = 0.0;
d_test_statistics = 0.0;
d_state = 1;
d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
consume_each(ninput_items[0]);
break;
}
case 1:
{
std::unique_lock<std::mutex> lk( d_mutex );
int num_items_consumed = 1;
if( d_worker_active )
// Copy the data to the core and let it know that new data is available
memcpy(d_data_buffer, input_items[0], d_fft_size * sizeof(lv_16sc_t));
if(d_blocking)
{
if( d_blocking )
{
// Should never get here:
std::string msg = "pcps_acquisition_sc: Entered general work with worker active in blocking mode, should never happen";
LOG(WARNING) << msg;
std::cout << msg << std::endl;
d_cond.wait( lk, [&]{ return !this->d_worker_active; } );
}
else
{
num_items_consumed = ninput_items[0];
d_sample_counter += d_fft_size * num_items_consumed;
}
lk.unlock();
acquisition_core(d_sample_counter);
}
else
{
// Copy the data to the core and let it know that new data is available
memcpy( d_data_buffer, input_items[0], d_fft_size * sizeof( lv_16sc_t ) );
d_new_data_available = true;
d_cond.notify_one();
if( d_blocking )
{
d_cond.wait( lk, [&]{ return !this->d_new_data_available; } );
}
gr::thread::thread d_worker(&pcps_acquisition_sc::acquisition_core, this, d_sample_counter);
d_worker_active = true;
}
consume_each(num_items_consumed);
d_sample_counter += d_fft_size;
consume_each(1);
break;
} // case 1, switch d_state
} // switch d_state
return noutput_items;
}
}
return 0;
}
void pcps_acquisition_sc::acquisition_core( void )
void pcps_acquisition_sc::acquisition_core( unsigned long int samp_count )
{
d_worker_active = false;
while( 1 )
gr::thread::scoped_lock lk(d_setlock);
// initialize acquisition algorithm
int doppler;
uint32_t indext = 0;
float magt = 0.0;
const lv_16sc_t *in = d_data_buffer; //Get the input samples pointer
int effective_fft_size = ( d_bit_transition_flag ? d_fft_size/2 : d_fft_size );
float fft_normalization_factor = static_cast<float>(d_fft_size) * static_cast<float>(d_fft_size);
d_input_power = 0.0;
d_mag = 0.0;
d_well_count++;
volk_gnsssdr_16ic_convert_32fc(d_in_32fc, in, effective_fft_size);
DLOG(INFO) << "Channel: " << d_channel
<< " , doing acquisition of satellite: " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN
<< " ,sample stamp: " << samp_count << ", threshold: "
<< d_threshold << ", doppler_max: " << d_doppler_max
<< ", doppler_step: " << d_doppler_step
<< ", use_CFAR_algorithm_flag: " << ( d_use_CFAR_algorithm_flag ? "true" : "false" );
lk.unlock();
if (d_use_CFAR_algorithm_flag)
{
std::unique_lock<std::mutex> lk( d_mutex );
d_cond.wait( lk, [&]{ return this->d_new_data_available or this->d_done; } );
d_worker_active = !d_done;
unsigned long int sample_counter = d_sample_counter; // sample counter
lk.unlock();
// 1- (optional) Compute the input signal power estimation
volk_32fc_magnitude_squared_32f(d_magnitude, d_in_32fc, d_fft_size);
volk_32f_accumulator_s32f(&d_input_power, d_magnitude, d_fft_size);
d_input_power /= static_cast<float>(d_fft_size);
}
// 2- Doppler frequency search loop
for (unsigned int doppler_index = 0; doppler_index < d_num_doppler_bins; doppler_index++)
{
// doppler search steps
doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
if( d_done )
volk_32fc_x2_multiply_32fc(d_fft_if->get_inbuf(), d_in_32fc, d_grid_doppler_wipeoffs[doppler_index], d_fft_size);
// 3- Perform the FFT-based convolution (parallel time search)
// Compute the FFT of the carrier wiped--off incoming signal
d_fft_if->execute();
// Multiply carrier wiped--off, Fourier transformed incoming signal
// with the local FFT'd code reference using SIMD operations with VOLK library
volk_32fc_x2_multiply_32fc(d_ifft->get_inbuf(), d_fft_if->get_outbuf(), d_fft_codes, d_fft_size);
// compute the inverse FFT
d_ifft->execute();
// Search maximum
size_t offset = ( d_bit_transition_flag ? effective_fft_size : 0 );
volk_32fc_magnitude_squared_32f(d_magnitude, d_ifft->get_outbuf() + offset, effective_fft_size);
volk_gnsssdr_32f_index_max_32u(&indext, d_magnitude, effective_fft_size);
magt = d_magnitude[indext];
if (d_use_CFAR_algorithm_flag)
{
break;
// Normalize the maximum value to correct the scale factor introduced by FFTW
magt = d_magnitude[indext] / (fft_normalization_factor * fft_normalization_factor);
}
// initialize acquisition algorithm
int doppler;
uint32_t indext = 0;
float magt = 0.0;
const lv_16sc_t *in = d_data_buffer; //Get the input samples pointer
int effective_fft_size = ( d_bit_transition_flag ? d_fft_size/2 : d_fft_size );
//TODO: optimize the signal processing chain to not use gr_complex. This is a temporary solution
volk_gnsssdr_16ic_convert_32fc(d_in_32fc, in, effective_fft_size);
float fft_normalization_factor = static_cast<float>(d_fft_size) * static_cast<float>(d_fft_size);
d_input_power = 0.0;
d_mag = 0.0;
d_well_count++;
DLOG(INFO) << "Channel: " << d_channel
<< " , doing acquisition of satellite: " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN
<< " ,sample stamp: " << sample_counter << ", threshold: "
<< d_threshold << ", doppler_max: " << d_doppler_max
<< ", doppler_step: " << d_doppler_step
<< ", use_CFAR_algorithm_flag: " << ( d_use_CFAR_algorithm_flag ? "true" : "false" );
if (d_use_CFAR_algorithm_flag == true)
// 4- record the maximum peak and the associated synchronization parameters
if (d_mag < magt)
{
// 1- (optional) Compute the input signal power estimation
volk_32fc_magnitude_squared_32f(d_magnitude, d_in_32fc, d_fft_size);
volk_32f_accumulator_s32f(&d_input_power, d_magnitude, d_fft_size);
d_input_power /= static_cast<float>(d_fft_size);
}
// 2- Doppler frequency search loop
for (unsigned int doppler_index = 0; doppler_index < d_num_doppler_bins; doppler_index++)
{
// doppler search steps
doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
d_mag = magt;
volk_32fc_x2_multiply_32fc(d_fft_if->get_inbuf(), d_in_32fc,
d_grid_doppler_wipeoffs[doppler_index], d_fft_size);
// 3- Perform the FFT-based convolution (parallel time search)
// Compute the FFT of the carrier wiped--off incoming signal
d_fft_if->execute();
// Multiply carrier wiped--off, Fourier transformed incoming signal
// with the local FFT'd code reference using SIMD operations with VOLK library
volk_32fc_x2_multiply_32fc(d_ifft->get_inbuf(),
d_fft_if->get_outbuf(), d_fft_codes, d_fft_size);
// compute the inverse FFT
d_ifft->execute();
// Search maximum
size_t offset = ( d_bit_transition_flag ? effective_fft_size : 0 );
volk_32fc_magnitude_squared_32f(d_magnitude, d_ifft->get_outbuf() + offset, effective_fft_size);
volk_gnsssdr_32f_index_max_32u(&indext, d_magnitude, effective_fft_size);
magt = d_magnitude[indext];
if (d_use_CFAR_algorithm_flag == true)
if (!d_use_CFAR_algorithm_flag)
{
// Normalize the maximum value to correct the scale factor introduced by FFTW
magt = d_magnitude[indext] / (fft_normalization_factor * fft_normalization_factor);
// Search grid noise floor approximation for this doppler line
volk_32f_accumulator_s32f(&d_input_power, d_magnitude, effective_fft_size);
d_input_power = (d_input_power - d_mag) / (effective_fft_size - 1);
}
// 4- record the maximum peak and the associated synchronization parameters
if (d_mag < magt)
// In case that d_bit_transition_flag = true, we compare the potentially
// new maximum test statistics (d_mag/d_input_power) with the value in
// d_test_statistics. When the second dwell is being processed, the value
// of d_mag/d_input_power could be lower than d_test_statistics (i.e,
// the maximum test statistics in the previous dwell is greater than
// current d_mag/d_input_power). Note that d_test_statistics is not
// restarted between consecutive dwells in multidwell operation.
if (d_test_statistics < (d_mag / d_input_power) || !d_bit_transition_flag)
{
d_mag = magt;
d_gnss_synchro->Acq_delay_samples = static_cast<double>(indext % d_samples_per_code);
d_gnss_synchro->Acq_doppler_hz = static_cast<double>(doppler);
d_gnss_synchro->Acq_samplestamp_samples = samp_count;
if (d_use_CFAR_algorithm_flag == false)
// 5- Compute the test statistics and compare to the threshold
//d_test_statistics = 2 * d_fft_size * d_mag / d_input_power;
d_test_statistics = d_mag / d_input_power;
}
}
// Record results to file if required
if (d_dump)
{
memcpy(grid_.colptr(doppler_index), d_magnitude, sizeof(float) * effective_fft_size);
if(doppler_index == (d_num_doppler_bins - 1))
{
std::string filename = d_dump_filename;
filename.append("_");
filename.append(1, d_gnss_synchro->System);
filename.append("_");
filename.append(1, d_gnss_synchro->Signal[0]);
filename.append(1, d_gnss_synchro->Signal[1]);
filename.append("_sat_");
filename.append(std::to_string(d_gnss_synchro->PRN));
filename.append(".mat");
mat_t* matfp = Mat_CreateVer(filename.c_str(), NULL, MAT_FT_MAT73);
if(matfp == NULL)
{
// Search grid noise floor approximation for this doppler line
volk_32f_accumulator_s32f(&d_input_power, d_magnitude, effective_fft_size);
d_input_power = (d_input_power - d_mag) / (effective_fft_size - 1);
std::cout << "Unable to create or open Acquisition dump file" << std::endl;
d_dump = false;
}
// In case that d_bit_transition_flag = true, we compare the potentially
// new maximum test statistics (d_mag/d_input_power) with the value in
// d_test_statistics. When the second dwell is being processed, the value
// of d_mag/d_input_power could be lower than d_test_statistics (i.e,
// the maximum test statistics in the previous dwell is greater than
// current d_mag/d_input_power). Note that d_test_statistics is not
// restarted between consecutive dwells in multidwell operation.
if (d_test_statistics < (d_mag / d_input_power) || !d_bit_transition_flag)
else
{
d_gnss_synchro->Acq_delay_samples = static_cast<double>(indext % d_samples_per_code);
d_gnss_synchro->Acq_doppler_hz = static_cast<double>(doppler);
d_gnss_synchro->Acq_samplestamp_samples = sample_counter;
size_t dims[2] = {static_cast<size_t>(effective_fft_size), static_cast<size_t>(d_num_doppler_bins)};
matvar_t* matvar = Mat_VarCreate("grid", MAT_C_SINGLE, MAT_T_SINGLE, 2, dims, grid_.memptr(), 0);
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
Mat_VarFree(matvar);
// 5- Compute the test statistics and compare to the threshold
//d_test_statistics = 2 * d_fft_size * d_mag / d_input_power;
d_test_statistics = d_mag / d_input_power;
dims[0] = static_cast<size_t>(1);
dims[1] = static_cast<size_t>(1);
matvar = Mat_VarCreate("doppler_max", MAT_C_SINGLE, MAT_T_UINT32, 1, dims, &d_doppler_max, 0);
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
Mat_VarFree(matvar);
matvar = Mat_VarCreate("doppler_step", MAT_C_SINGLE, MAT_T_UINT32, 1, dims, &d_doppler_step, 0);
Mat_VarWrite(matfp, matvar, MAT_COMPRESSION_ZLIB); // or MAT_COMPRESSION_NONE
Mat_VarFree(matvar);
Mat_Close(matfp);
}
}
// Record results to file if required
if (d_dump)
{
std::stringstream filename;
std::streamsize n = 2 * sizeof(float) * (d_fft_size); // complex file write
filename.str("");
boost::filesystem::path p = d_dump_filename;
filename << p.parent_path().string()
<< boost::filesystem::path::preferred_separator
<< p.stem().string()
<< "_" << d_gnss_synchro->System
<<"_" << d_gnss_synchro->Signal << "_sat_"
<< d_gnss_synchro->PRN << "_doppler_"
<< doppler
<< p.extension().string();
DLOG(INFO) << "Writing ACQ out to " << filename.str();
d_dump_file.open(filename.str().c_str(), std::ios::out | std::ios::binary);
d_dump_file.write(reinterpret_cast<char*>(d_ifft->get_outbuf()), n); //write directly |abs(x)|^2 in this Doppler bin?
d_dump_file.close();
}
}
if (!d_bit_transition_flag)
}
lk.lock();
if (!d_bit_transition_flag)
{
if (d_test_statistics > d_threshold)
{
d_state = 0; // Positive acquisition
d_active = false;
send_positive_acquisition();
}
else if (d_well_count == d_max_dwells)
{
d_state = 0;
d_active = false;
send_negative_acquisition();
}
}
else
{
if (d_well_count == d_max_dwells) // d_max_dwells = 2
{
if (d_test_statistics > d_threshold)
{
@ -571,66 +547,13 @@ void pcps_acquisition_sc::acquisition_core( void )
d_active = false;
send_positive_acquisition();
}
else if (d_well_count == d_max_dwells)
else
{
d_state = 0;
d_state = 0; // Negative acquisition
d_active = false;
send_negative_acquisition();
}
}
else
{
if (d_well_count == d_max_dwells) // d_max_dwells = 2
{
if (d_test_statistics > d_threshold)
{
d_state = 0; // Positive acquisition
d_active = false;
send_positive_acquisition();
}
else
{
d_state = 0; // Negative acquisition
d_active = false;
send_negative_acquisition();
}
}
}
lk.lock();
d_worker_active = false;
d_new_data_available = false;
lk.unlock();
d_cond.notify_one();
}
}
bool pcps_acquisition_sc::start( void )
{
d_worker_active = false;
d_done = false;
// Start the worker thread and wait for it to acknowledge:
d_worker_thread = std::move( std::thread( &pcps_acquisition_sc::acquisition_core, this ) );
return gr::block::start();
}
bool pcps_acquisition_sc::stop( void )
{
// Let the worker thread know that we are done and then wait to join
if( d_worker_thread.joinable() )
{
{
std::lock_guard<std::mutex> lk( d_mutex );
d_done = true;
d_cond.notify_one();
}
d_worker_thread.join();
}
return gr::block::stop();
}

66
src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.h
View File

@ -51,13 +51,9 @@
#ifndef GNSS_SDR_PCPS_ACQUISITION_SC_H_
#define GNSS_SDR_PCPS_ACQUISITION_SC_H_
#include <fstream>
#include <string>
#include <mutex>
#include <thread>
#include <condition_variable>
#include <armadillo>
#include <gnuradio/block.h>
#include <gnuradio/gr_complex.h>
#include <gnuradio/fft/fft.h>
#include <volk_gnsssdr/volk_gnsssdr.h>
#include "gnss_synchro.h"
@ -101,7 +97,7 @@ private:
void update_local_carrier(gr_complex* carrier_vector, int correlator_length_samples, float freq);
void acquisition_core( void );
void acquisition_core( unsigned long int samp_count );
void update_grid_doppler_wipeoffs();
bool is_fdma();
@ -109,53 +105,42 @@ private:
void send_negative_acquisition();
void send_positive_acquisition();
bool d_bit_transition_flag;
bool d_use_CFAR_algorithm_flag;
bool d_active;
bool d_dump;
bool d_worker_active;
bool d_blocking;
float d_threshold;
float d_mag;
float d_input_power;
float d_test_statistics;
float* d_magnitude;
long d_fs_in;
long d_freq;
long d_old_freq;
int d_samples_per_ms;
int d_samples_per_code;
//unsigned int d_doppler_resolution;
float d_threshold;
std::string d_satellite_str;
int d_state;
unsigned int d_channel;
unsigned int d_doppler_max;
unsigned int d_doppler_step;
unsigned int d_sampled_ms;
unsigned int d_max_dwells;
unsigned int d_well_count;
unsigned int d_fft_size;
unsigned long int d_sample_counter;
gr_complex** d_grid_doppler_wipeoffs;
unsigned int d_num_doppler_bins;
unsigned int d_code_phase;
unsigned long int d_sample_counter;
lv_16sc_t* d_data_buffer;
gr_complex** d_grid_doppler_wipeoffs;
gr_complex* d_fft_codes;
gr_complex* d_in_32fc;
gr::fft::fft_complex* d_fft_if;
gr::fft::fft_complex* d_ifft;
Gnss_Synchro *d_gnss_synchro;
unsigned int d_code_phase;
float d_doppler_freq;
float d_mag;
float* d_magnitude;
float d_input_power;
float d_test_statistics;
bool d_bit_transition_flag;
bool d_use_CFAR_algorithm_flag;
std::ofstream d_dump_file;
bool d_active;
int d_state;
bool d_dump;
unsigned int d_channel;
Gnss_Synchro* d_gnss_synchro;
std::string d_dump_filename;
std::thread d_worker_thread;
std::mutex d_mutex;
std::condition_variable d_cond;
bool d_done;
bool d_new_data_available;
bool d_worker_active;
bool d_blocking;
lv_16sc_t *d_data_buffer;
arma::fmat grid_;
public:
/*!
@ -259,15 +244,6 @@ public:
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items);
/*!
* Called by the flowgraph when processing is about to start.
*/
bool start( void );
/*!
* Called by the flowgraph when processing is done.
*/
bool stop( void );
};
#endif /* GNSS_SDR_PCPS_ACQUISITION_SC_H_*/