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gnss-sdr/src/algorithms/acquisition/adapters/gps_l5i_pcps_acquisition_fp...

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/*!
* \file gps_l5i pcps_acquisition.cc
* \brief Adapts a PCPS acquisition block to an Acquisition Interface for
* GPS L5i signals
* \authors <ul>
* <li> Javier Arribas, 2017. jarribas(at)cttc.es
* </ul>
*
* -------------------------------------------------------------------------
*
* Copyright (C) 2010-2017 (see AUTHORS file for a list of contributors)
*
* GNSS-SDR is a software defined Global Navigation
* Satellite Systems receiver
*
* This file is part of GNSS-SDR.
*
* GNSS-SDR is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GNSS-SDR is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNSS-SDR. If not, see <http://www.gnu.org/licenses/>.
*
* -------------------------------------------------------------------------
*/
#include "gps_l5i_pcps_acquisition_fpga.h"
#include "configuration_interface.h"
#include "gps_l5_signal.h"
#include "GPS_L5.h"
#include "gnss_sdr_flags.h"
#include <boost/math/distributions/exponential.hpp>
#include <glog/logging.h>
#define NUM_PRNs 32
using google::LogMessage;
GpsL5iPcpsAcquisitionFpga::GpsL5iPcpsAcquisitionFpga(
ConfigurationInterface* configuration,
const std::string& role,
unsigned int in_streams,
unsigned int out_streams) : role_(role),
in_streams_(in_streams),
out_streams_(out_streams)
{
//printf("L5 ACQ CLASS CREATED\n");
pcpsconf_fpga_t acq_parameters;
configuration_ = configuration;
std::string default_item_type = "gr_complex";
std::string default_dump_filename = "./acquisition.mat";
LOG(INFO) << "role " << role;
//item_type_ = configuration_->property(role + ".item_type", default_item_type);
int64_t fs_in_deprecated = configuration_->property("GNSS-SDR.internal_fs_hz", 2048000);
int64_t fs_in = configuration_->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
acq_parameters.fs_in = fs_in;
//if_ = configuration_->property(role + ".if", 0);
//acq_parameters.freq = if_;
//dump_ = configuration_->property(role + ".dump", false);
//acq_parameters.dump = dump_;
//blocking_ = configuration_->property(role + ".blocking", true);
//acq_parameters.blocking = blocking_;
doppler_max_ = configuration->property(role + ".doppler_max", 5000);
if (FLAGS_doppler_max != 0) doppler_max_ = FLAGS_doppler_max;
acq_parameters.doppler_max = doppler_max_;
//acq_parameters.sampled_ms = 1;
unsigned int sampled_ms = configuration_->property(role + ".coherent_integration_time_ms", 1);
acq_parameters.sampled_ms = sampled_ms;
//printf("L5 ACQ CLASS MID 0\n");
//bit_transition_flag_ = configuration_->property(role + ".bit_transition_flag", false);
//acq_parameters.bit_transition_flag = bit_transition_flag_;
//use_CFAR_algorithm_flag_ = configuration_->property(role + ".use_CFAR_algorithm", true); //will be false in future versions
//acq_parameters.use_CFAR_algorithm_flag = use_CFAR_algorithm_flag_;
//max_dwells_ = configuration_->property(role + ".max_dwells", 1);
//acq_parameters.max_dwells = max_dwells_;
//dump_filename_ = configuration_->property(role + ".dump_filename", default_dump_filename);
//acq_parameters.dump_filename = dump_filename_;
//--- Find number of samples per spreading code -------------------------
unsigned int code_length = static_cast<unsigned int>(std::round(static_cast<double>(fs_in) / (GPS_L5i_CODE_RATE_HZ / static_cast<double>(GPS_L5i_CODE_LENGTH_CHIPS))));
acq_parameters.code_length = code_length;
// The FPGA can only use FFT lengths that are a power of two.
float nbits = ceilf(log2f((float)code_length));
unsigned int nsamples_total = pow(2, nbits);
unsigned int vector_length = nsamples_total;
unsigned int select_queue_Fpga = configuration_->property(role + ".select_queue_Fpga", 1);
acq_parameters.select_queue_Fpga = select_queue_Fpga;
std::string default_device_name = "/dev/uio0";
std::string device_name = configuration_->property(role + ".devicename", default_device_name);
acq_parameters.device_name = device_name;
acq_parameters.samples_per_ms = nsamples_total;
acq_parameters.samples_per_code = nsamples_total;
//printf("L5 ACQ CLASS MID 01\n");
// compute all the GPS L5 PRN Codes (this is done only once upon the class constructor in order to avoid re-computing the PRN codes every time
// a channel is assigned)
gr::fft::fft_complex* fft_if = new gr::fft::fft_complex(vector_length, true); // Direct FFT
//printf("L5 ACQ CLASS MID 02\n");
std::complex<float>* code = new gr_complex[vector_length];
//printf("L5 ACQ CLASS MID 03\n");
gr_complex* fft_codes_padded = static_cast<gr_complex*>(volk_gnsssdr_malloc(nsamples_total * sizeof(gr_complex), volk_gnsssdr_get_alignment()));
//printf("L5 ACQ CLASS MID 04\n");
d_all_fft_codes_ = new lv_16sc_t[nsamples_total * NUM_PRNs]; // memory containing all the possible fft codes for PRN 0 to 32
//printf("L5 ACQ CLASS MID 1 vector_length = %d\n", vector_length);
float max; // temporary maxima search
for (unsigned int PRN = 1; PRN <= NUM_PRNs; PRN++)
{
//printf("L5 ACQ CLASS processing PRN = %d\n", PRN);
gps_l5i_code_gen_complex_sampled(code, PRN, fs_in);
//printf("L5 ACQ CLASS processing PRN = %d (cont) \n", PRN);
// fill in zero padding
for (int s = code_length; s < nsamples_total; s++)
{
code[s] = std::complex<float>(static_cast<float>(0, 0));
//code[s] = 0;
}
memcpy(fft_if->get_inbuf(), code, sizeof(gr_complex) * nsamples_total); // copy to FFT buffer
fft_if->execute(); // Run the FFT of local code
volk_32fc_conjugate_32fc(fft_codes_padded, fft_if->get_outbuf(), nsamples_total); // conjugate values
max = 0; // initialize maximum value
for (unsigned int i = 0; i < nsamples_total; i++) // search for maxima
{
if (std::abs(fft_codes_padded[i].real()) > max)
{
max = std::abs(fft_codes_padded[i].real());
}
if (std::abs(fft_codes_padded[i].imag()) > max)
{
max = std::abs(fft_codes_padded[i].imag());
}
}
for (unsigned int i = 0; i < nsamples_total; i++) // map the FFT to the dynamic range of the fixed point values an copy to buffer containing all FFTs
{
//d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int>(floor(256*fft_codes_padded[i].real() * (pow(2, 7) - 1) / max)),
// static_cast<int>(floor(256*fft_codes_padded[i].imag() * (pow(2, 7) - 1) / max)));
//d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int>(16*floor(fft_codes_padded[i].real() * (pow(2, 11) - 1) / max)),
// static_cast<int>(16*floor(fft_codes_padded[i].imag() * (pow(2, 11) - 1) / max)));
//d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int>(floor(fft_codes_padded[i].real() * (pow(2, 15) - 1) / max)),
// static_cast<int>(floor(fft_codes_padded[i].imag() * (pow(2, 15) - 1) / max)));
d_all_fft_codes_[i + nsamples_total * (PRN - 1)] = lv_16sc_t(static_cast<int>(floor(fft_codes_padded[i].real() * (pow(2, 15) - 1) / max)),
static_cast<int>(floor(fft_codes_padded[i].imag() * (pow(2, 15) - 1) / max)));
}
}
//printf("L5 ACQ CLASS MID 2\n");
//acq_parameters
acq_parameters.all_fft_codes = d_all_fft_codes_;
// temporary buffers that we can delete
delete[] code;
delete fft_if;
delete[] fft_codes_padded;
// vector_length_ = code_length_;
//
// if (bit_transition_flag_)
// {
// vector_length_ *= 2;
// }
//
// code_ = new gr_complex[vector_length_];
//
// if (item_type_.compare("cshort") == 0)
// {
// item_size_ = sizeof(lv_16sc_t);
// }
// else
// {
// item_size_ = sizeof(gr_complex);
// }
// acq_parameters.samples_per_code = code_length_;
// acq_parameters.samples_per_ms = code_length_;
// acq_parameters.it_size = item_size_;
//acq_parameters.sampled_ms = 1;
// acq_parameters.num_doppler_bins_step2 = configuration_->property(role + ".second_nbins", 4);
// acq_parameters.doppler_step2 = configuration_->property(role + ".second_doppler_step", 125.0);
// acq_parameters.make_2_steps = configuration_->property(role + ".make_two_steps", false);
// acquisition_fpga_ = pcps_make_acquisition(acq_parameters);
// DLOG(INFO) << "acquisition(" << acquisition_fpga_->unique_id() << ")";
acquisition_fpga_ = pcps_make_acquisition_fpga(acq_parameters);
DLOG(INFO) << "acquisition(" << acquisition_fpga_->unique_id() << ")";
// stream_to_vector_ = gr::blocks::stream_to_vector::make(item_size_, vector_length_);
// DLOG(INFO) << "stream_to_vector(" << stream_to_vector_->unique_id() << ")";
//
// if (item_type_.compare("cbyte") == 0)
// {
// cbyte_to_float_x2_ = make_complex_byte_to_float_x2();
// float_to_complex_ = gr::blocks::float_to_complex::make();
// }
channel_ = 0;
// threshold_ = 0.0;
doppler_step_ = 0;
gnss_synchro_ = nullptr;
//printf("L5 ACQ CLASS FINISHED\n");
}
GpsL5iPcpsAcquisitionFpga::~GpsL5iPcpsAcquisitionFpga()
{
//delete[] code_;
delete[] d_all_fft_codes_;
}
void GpsL5iPcpsAcquisitionFpga::stop_acquisition()
{
}
void GpsL5iPcpsAcquisitionFpga::set_channel(unsigned int channel)
{
channel_ = channel;
acquisition_fpga_->set_channel(channel_);
}
void GpsL5iPcpsAcquisitionFpga::set_threshold(float threshold)
{
// float pfa = configuration_->property(role_ + std::to_string(channel_) + ".pfa", 0.0);
//
// if (pfa == 0.0)
// {
// pfa = configuration_->property(role_ + ".pfa", 0.0);
// }
// if (pfa == 0.0)
// {
// threshold_ = threshold;
// }
// else
// {
// threshold_ = calculate_threshold(pfa);
// }
// DLOG(INFO) << "Channel " << channel_ << " Threshold = " << threshold_;
// the .pfa parameter and the threshold calculation is only used for the CFAR algorithm.
// We don't use the CFAR algorithm in the FPGA. Therefore the threshold is set as such.
DLOG(INFO) << "Channel " << channel_ << " Threshold = " << threshold;
acquisition_fpga_->set_threshold(threshold);
}
void GpsL5iPcpsAcquisitionFpga::set_doppler_max(unsigned int doppler_max)
{
doppler_max_ = doppler_max;
acquisition_fpga_->set_doppler_max(doppler_max_);
}
// Be aware that Doppler step should be set to 2/(3T) Hz, where T is the coherent integration time (GPS L2 period is 0.02s)
// Doppler bin minimum size= 33 Hz
void GpsL5iPcpsAcquisitionFpga::set_doppler_step(unsigned int doppler_step)
{
doppler_step_ = doppler_step;
acquisition_fpga_->set_doppler_step(doppler_step_);
}
void GpsL5iPcpsAcquisitionFpga::set_gnss_synchro(Gnss_Synchro* gnss_synchro)
{
gnss_synchro_ = gnss_synchro;
acquisition_fpga_->set_gnss_synchro(gnss_synchro_);
}
signed int GpsL5iPcpsAcquisitionFpga::mag()
{
return acquisition_fpga_->mag();
}
void GpsL5iPcpsAcquisitionFpga::init()
{
acquisition_fpga_->init();
}
void GpsL5iPcpsAcquisitionFpga::set_local_code()
{
acquisition_fpga_->set_local_code();
}
void GpsL5iPcpsAcquisitionFpga::reset()
{
acquisition_fpga_->set_active(true);
}
void GpsL5iPcpsAcquisitionFpga::set_state(int state)
{
acquisition_fpga_->set_state(state);
}
//float GpsL5iPcpsAcquisitionFpga::calculate_threshold(float pfa)
//{
// //Calculate the threshold
// unsigned int frequency_bins = 0;
// for (int doppler = static_cast<int>(-doppler_max_); doppler <= static_cast<int>(doppler_max_); doppler += doppler_step_)
// {
// frequency_bins++;
// }
// DLOG(INFO) << "Channel " << channel_ << " Pfa = " << pfa;
// unsigned int ncells = vector_length_ * frequency_bins;
// double exponent = 1.0 / static_cast<double>(ncells);
// double val = pow(1.0 - pfa, exponent);
// double lambda = double(vector_length_);
// boost::math::exponential_distribution<double> mydist(lambda);
// float threshold = static_cast<float>(quantile(mydist, val));
//
// return threshold;
//}
void GpsL5iPcpsAcquisitionFpga::connect(gr::top_block_sptr top_block)
{
// if (item_type_.compare("gr_complex") == 0)
// {
// top_block->connect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else if (item_type_.compare("cshort") == 0)
// {
// top_block->connect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else if (item_type_.compare("cbyte") == 0)
// {
// top_block->connect(cbyte_to_float_x2_, 0, float_to_complex_, 0);
// top_block->connect(cbyte_to_float_x2_, 1, float_to_complex_, 1);
// top_block->connect(float_to_complex_, 0, stream_to_vector_, 0);
// top_block->connect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else
// {
// LOG(WARNING) << item_type_ << " unknown acquisition item type";
// }
// nothing to connect
}
void GpsL5iPcpsAcquisitionFpga::disconnect(gr::top_block_sptr top_block)
{
// if (item_type_.compare("gr_complex") == 0)
// {
// top_block->disconnect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else if (item_type_.compare("cshort") == 0)
// {
// top_block->disconnect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else if (item_type_.compare("cbyte") == 0)
// {
// // Since a byte-based acq implementation is not available,
// // we just convert cshorts to gr_complex
// top_block->disconnect(cbyte_to_float_x2_, 0, float_to_complex_, 0);
// top_block->disconnect(cbyte_to_float_x2_, 1, float_to_complex_, 1);
// top_block->disconnect(float_to_complex_, 0, stream_to_vector_, 0);
// top_block->disconnect(stream_to_vector_, 0, acquisition_fpga_, 0);
// }
// else
// {
// LOG(WARNING) << item_type_ << " unknown acquisition item type";
// }
// nothing to disconnect
}
gr::basic_block_sptr GpsL5iPcpsAcquisitionFpga::get_left_block()
{
// if (item_type_.compare("gr_complex") == 0)
// {
// return stream_to_vector_;
// }
// else if (item_type_.compare("cshort") == 0)
// {
// return stream_to_vector_;
// }
// else if (item_type_.compare("cbyte") == 0)
// {
// return cbyte_to_float_x2_;
// }
// else
// {
// LOG(WARNING) << item_type_ << " unknown acquisition item type";
// return nullptr;
// }
return nullptr;
}
gr::basic_block_sptr GpsL5iPcpsAcquisitionFpga::get_right_block()
{
return acquisition_fpga_;
}
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