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Merge branch 'new_volk_module' of git+ssh://github.com/gnss-sdr/gnss-sdr

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# especially if it merges an updated upstream into a topic branch.
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This commit is contained in:
Carles Fernandez 2016-01-20 18:40:27 +01:00
commit 7e11a6ef72
6 changed files with 836 additions and 72 deletions
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1
src/algorithms/acquisition/adapters/CMakeLists.txt
View File

@ -50,6 +50,7 @@ include_directories(
${GFlags_INCLUDE_DIRS}
${GNURADIO_RUNTIME_INCLUDE_DIRS}
${GNURADIO_BLOCKS_INCLUDE_DIRS}
${VOLK_GNSSSDR_INCLUDE_DIRS}
)
file(GLOB ACQ_ADAPTER_HEADERS "*.h")

184
src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc
View File

@ -84,36 +84,36 @@ GpsL1CaPcpsAcquisition::GpsL1CaPcpsAcquisition(
code_ = new gr_complex[vector_length_];
// if (item_type_.compare("gr_complex") == 0 )
// {
item_size_ = sizeof(gr_complex);
acquisition_cc_ = pcps_make_acquisition_cc(sampled_ms_, max_dwells_,
if (item_type_.compare("cshort") == 0 )
{
item_size_ = sizeof(lv_16sc_t);
acquisition_sc_ = pcps_make_acquisition_sc(sampled_ms_, max_dwells_,
shift_resolution_, if_, fs_in_, code_length_, code_length_,
bit_transition_flag_, queue_, dump_, dump_filename_);
DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id() << ")";
}else{
item_size_ = sizeof(gr_complex);
acquisition_cc_ = pcps_make_acquisition_cc(sampled_ms_, max_dwells_,
shift_resolution_, if_, fs_in_, code_length_, code_length_,
bit_transition_flag_, queue_, dump_, dump_filename_);
DLOG(INFO) << "acquisition(" << acquisition_cc_->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() << ")";
DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id() << ")";
// }
if (item_type_.compare("cshort") == 0)
{
cshort_to_float_x2_ = make_cshort_to_float_x2();
float_to_complex_ = gr::blocks::float_to_complex::make();
}
//now is supported natively by the acquisition (_sc variant)
// if (item_type_.compare("cshort") == 0)
// {
// cshort_to_float_x2_ = make_cshort_to_float_x2();
// float_to_complex_ = gr::blocks::float_to_complex::make();
// }
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();
}
//}
//else
// {
// LOG(WARNING) << item_type_
// << " unknown acquisition item type";
// }
channel_ = 0;
threshold_ = 0.0;
doppler_max_ = 0;
@ -132,10 +132,13 @@ GpsL1CaPcpsAcquisition::~GpsL1CaPcpsAcquisition()
void GpsL1CaPcpsAcquisition::set_channel(unsigned int channel)
{
channel_ = channel;
//if (item_type_.compare("gr_complex") == 0)
//{
acquisition_cc_->set_channel(channel_);
//}
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_channel(channel_);
}else{
acquisition_cc_->set_channel(channel_);
}
}
@ -155,30 +158,39 @@ void GpsL1CaPcpsAcquisition::set_threshold(float threshold)
DLOG(INFO) << "Channel " << channel_ << " Threshold = " << threshold_;
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_threshold(threshold_);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_threshold(threshold_);
}else{
acquisition_cc_->set_threshold(threshold_);
}
}
void GpsL1CaPcpsAcquisition::set_doppler_max(unsigned int doppler_max)
{
doppler_max_ = doppler_max;
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_doppler_max(doppler_max_);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_doppler_max(doppler_max_);
}else{
acquisition_cc_->set_doppler_max(doppler_max_);
}
}
void GpsL1CaPcpsAcquisition::set_doppler_step(unsigned int doppler_step)
{
doppler_step_ = doppler_step;
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_doppler_step(doppler_step_);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_doppler_step(doppler_step_);
}else{
acquisition_cc_->set_doppler_step(doppler_step_);
}
}
@ -187,39 +199,49 @@ void GpsL1CaPcpsAcquisition::set_channel_queue(
concurrent_queue<int> *channel_internal_queue)
{
channel_internal_queue_ = channel_internal_queue;
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_channel_queue(channel_internal_queue_);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_channel_queue(channel_internal_queue_);
}else{
acquisition_cc_->set_channel_queue(channel_internal_queue_);
}
}
void GpsL1CaPcpsAcquisition::set_gnss_synchro(Gnss_Synchro* gnss_synchro)
{
gnss_synchro_ = gnss_synchro;
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_gnss_synchro(gnss_synchro_);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_gnss_synchro(gnss_synchro_);
}else{
acquisition_cc_->set_gnss_synchro(gnss_synchro_);
}
}
signed int GpsL1CaPcpsAcquisition::mag()
{
// // if (item_type_.compare("gr_complex") == 0)
// {
return acquisition_cc_->mag();
// }
// else
// {
// return 0;
// }
if (item_type_.compare("cshort") == 0)
{
return acquisition_sc_->mag();
}else{
return acquisition_cc_->mag();
}
}
void GpsL1CaPcpsAcquisition::init()
{
acquisition_cc_->init();
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->init();
}else{
acquisition_cc_->init();
}
set_local_code();
}
@ -238,7 +260,13 @@ void GpsL1CaPcpsAcquisition::set_local_code()
sizeof(gr_complex)*code_length_);
}
acquisition_cc_->set_local_code(code_);
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_local_code(code_);
}else{
acquisition_cc_->set_local_code(code_);
}
delete[] code;
// }
@ -247,18 +275,23 @@ void GpsL1CaPcpsAcquisition::set_local_code()
void GpsL1CaPcpsAcquisition::reset()
{
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_active(true);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_active(true);
}else{
acquisition_cc_->set_active(true);
}
}
void GpsL1CaPcpsAcquisition::set_state(int state)
{
// if (item_type_.compare("gr_complex") == 0)
// {
acquisition_cc_->set_state(state);
// }
if (item_type_.compare("cshort") == 0)
{
acquisition_sc_->set_state(state);
}else{
acquisition_cc_->set_state(state);
}
}
@ -291,10 +324,12 @@ void GpsL1CaPcpsAcquisition::connect(gr::top_block_sptr top_block)
}
else if (item_type_.compare("cshort") == 0)
{
top_block->connect(cshort_to_float_x2_, 0, float_to_complex_, 0);
top_block->connect(cshort_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_cc_, 0);
//top_block->connect(cshort_to_float_x2_, 0, float_to_complex_, 0);
//top_block->connect(cshort_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_cc_, 0);
top_block->connect(stream_to_vector_, 0, acquisition_sc_, 0);
}
else if (item_type_.compare("cbyte") == 0)
{
@ -320,10 +355,11 @@ void GpsL1CaPcpsAcquisition::disconnect(gr::top_block_sptr top_block)
{
// Since a short-based acq implementation is not available,
// we just convert cshorts to gr_complex
top_block->disconnect(cshort_to_float_x2_, 0, float_to_complex_, 0);
top_block->disconnect(cshort_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_cc_, 0);
//top_block->disconnect(cshort_to_float_x2_, 0, float_to_complex_, 0);
//top_block->disconnect(cshort_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_cc_, 0);
top_block->disconnect(stream_to_vector_, 0, acquisition_sc_, 0);
}
else if (item_type_.compare("cbyte") == 0)
{
@ -349,7 +385,8 @@ gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_left_block()
}
else if (item_type_.compare("cshort") == 0)
{
return cshort_to_float_x2_;
//return cshort_to_float_x2_;
return stream_to_vector_;
}
else if (item_type_.compare("cbyte") == 0)
{
@ -365,6 +402,11 @@ gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_left_block()
gr::basic_block_sptr GpsL1CaPcpsAcquisition::get_right_block()
{
return acquisition_cc_;
if (item_type_.compare("cshort") == 0)
{
return acquisition_sc_;
}else{
return acquisition_cc_;
}
}

3
src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h
View File

@ -43,8 +43,10 @@
#include "gnss_synchro.h"
#include "acquisition_interface.h"
#include "pcps_acquisition_cc.h"
#include "pcps_acquisition_sc.h"
#include "cshort_to_float_x2.h"
#include "complex_byte_to_float_x2.h"
#include <volk_gnsssdr/volk_gnsssdr.h>
@ -145,6 +147,7 @@ public:
private:
ConfigurationInterface* configuration_;
pcps_acquisition_cc_sptr acquisition_cc_;
pcps_acquisition_sc_sptr acquisition_sc_;
gr::blocks::stream_to_vector::sptr stream_to_vector_;
gr::blocks::float_to_complex::sptr float_to_complex_;
cshort_to_float_x2_sptr cshort_to_float_x2_;

4
src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt
View File

@ -19,6 +19,7 @@
set(ACQ_GR_BLOCKS_SOURCES
pcps_acquisition_cc.cc
pcps_acquisition_sc.cc
pcps_multithread_acquisition_cc.cc
pcps_assisted_acquisition_cc.cc
pcps_acquisition_fine_doppler_cc.cc
@ -42,6 +43,7 @@ include_directories(
${GLOG_INCLUDE_DIRS}
${GFlags_INCLUDE_DIRS}
${GNURADIO_RUNTIME_INCLUDE_DIRS}
${VOLK_GNSSSDR_INCLUDE_DIRS}
)
@ -57,5 +59,5 @@ endif(OPENCL_FOUND)
file(GLOB ACQ_GR_BLOCKS_HEADERS "*.h")
add_library(acq_gr_blocks ${ACQ_GR_BLOCKS_SOURCES} ${ACQ_GR_BLOCKS_HEADERS})
source_group(Headers FILES ${ACQ_GR_BLOCKS_HEADERS})
target_link_libraries(acq_gr_blocks gnss_sp_libs gnss_system_parameters ${GNURADIO_RUNTIME_LIBRARIES} ${GNURADIO_FFT_LIBRARIES} ${VOLK_LIBRARIES} ${OPT_LIBRARIES})
target_link_libraries(acq_gr_blocks gnss_sp_libs gnss_system_parameters ${GNURADIO_RUNTIME_LIBRARIES} ${GNURADIO_FFT_LIBRARIES} ${VOLK_LIBRARIES} ${VOLK_GNSSSDR_LIBRARIES} ${OPT_LIBRARIES})

472
src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc Normal file
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@ -0,0 +1,472 @@
/*!
* \file pcps_acquisition_sc.cc
* \brief This class implements a Parallel Code Phase Search Acquisition
* \authors <ul>
* <li> Javier Arribas, 2011. jarribas(at)cttc.es
* <li> Luis Esteve, 2012. luis(at)epsilon-formacion.com
* <li> Marc Molina, 2013. marc.molina.pena@gmail.com
* </ul>
*
* -------------------------------------------------------------------------
*
* Copyright (C) 2010-2015 (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 "pcps_acquisition_sc.h"
#include <sstream>
#include <boost/filesystem.hpp>
#include <gnuradio/io_signature.h>
#include <glog/logging.h>
#include <volk/volk.h>
#include "gnss_signal_processing.h"
#include "control_message_factory.h"
#include <volk_gnsssdr/volk_gnsssdr.h>
using google::LogMessage;
pcps_acquisition_sc_sptr pcps_make_acquisition_sc(
unsigned int sampled_ms, unsigned int max_dwells,
unsigned int doppler_max, long freq, long fs_in,
int samples_per_ms, int samples_per_code,
bool bit_transition_flag,
gr::msg_queue::sptr queue, bool dump,
std::string dump_filename)
{
return pcps_acquisition_sc_sptr(
new pcps_acquisition_sc(sampled_ms, max_dwells, doppler_max, freq, fs_in, samples_per_ms,
samples_per_code, bit_transition_flag, queue, dump, dump_filename));
}
pcps_acquisition_sc::pcps_acquisition_sc(
unsigned int sampled_ms, unsigned int max_dwells,
unsigned int doppler_max, long freq, long fs_in,
int samples_per_ms, int samples_per_code,
bool bit_transition_flag,
gr::msg_queue::sptr queue, bool dump,
std::string dump_filename) :
gr::block("pcps_acquisition_sc",
gr::io_signature::make(1, 1, sizeof(lv_16sc_t) * sampled_ms * samples_per_ms * ( bit_transition_flag ? 2 : 1 )),
gr::io_signature::make(0, 0, 0))
{
d_sample_counter = 0; // SAMPLE COUNTER
d_active = false;
d_state = 0;
d_queue = queue;
d_freq = freq;
d_fs_in = fs_in;
d_samples_per_ms = samples_per_ms;
d_samples_per_code = samples_per_code;
d_sampled_ms = sampled_ms;
d_max_dwells = max_dwells;
d_well_count = 0;
d_doppler_max = doppler_max;
d_fft_size = d_sampled_ms * d_samples_per_ms;
d_mag = 0;
d_input_power = 0.0;
d_num_doppler_bins = 0;
d_bit_transition_flag = bit_transition_flag;
d_threshold = 0.0;
d_doppler_step = 250;
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
// The problem: Circular correlation is asynchronous with the received code.
// In effect the first code phase used in the correlation is the current
// estimate of the code phase at the start of the input buffer. If this is 1/2
// of the code period a bit transition would move all the signal energy into
// adjacent frequency bands at +/- 1/T where T is the integration time.
//
// We can avoid this by doing linear correlation, effectively doubling the
// size of the input buffer and padding the code with zeros.
if( d_bit_transition_flag )
{
d_fft_size *= 2;
d_max_dwells = 1;
}
d_fft_codes = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
d_magnitude = static_cast<float*>(volk_malloc(d_fft_size * sizeof(float), volk_get_alignment()));
//temporary storage for the input conversion from 16sc to float 32fc
d_in_32fc = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
// Direct FFT
d_fft_if = new gr::fft::fft_complex(d_fft_size, true);
// Inverse FFT
d_ifft = new gr::fft::fft_complex(d_fft_size, false);
// For dumping samples into a file
d_dump = dump;
d_dump_filename = dump_filename;
d_gnss_synchro = 0;
d_channel_internal_queue = 0;
d_grid_doppler_wipeoffs = 0;
}
pcps_acquisition_sc::~pcps_acquisition_sc()
{
if (d_num_doppler_bins > 0)
{
for (unsigned int i = 0; i < d_num_doppler_bins; i++)
{
volk_free(d_grid_doppler_wipeoffs[i]);
}
delete[] d_grid_doppler_wipeoffs;
}
volk_free(d_fft_codes);
volk_free(d_magnitude);
volk_free(d_in_32fc);
delete d_ifft;
delete d_fft_if;
if (d_dump)
{
d_dump_file.close();
}
}
void pcps_acquisition_sc::set_local_code(std::complex<float> * code)
{
// COD
// Here we want to create a buffer that looks like this:
// [ 0 0 0 ... 0 c_0 c_1 ... c_L]
// where c_i is the local code and there are L zeros and L chips
int offset = 0;
if( d_bit_transition_flag )
{
std::fill_n( d_fft_if->get_inbuf(), d_samples_per_code, gr_complex( 0.0, 0.0 ) );
offset = d_samples_per_code;
}
memcpy(d_fft_if->get_inbuf() + offset, code, sizeof(gr_complex) * d_samples_per_code);
d_fft_if->execute(); // We need the FFT of local code
volk_32fc_conjugate_32fc(d_fft_codes, d_fft_if->get_outbuf(), d_fft_size);
}
void pcps_acquisition_sc::init()
{
d_gnss_synchro->Acq_delay_samples = 0.0;
d_gnss_synchro->Acq_doppler_hz = 0.0;
d_gnss_synchro->Acq_samplestamp_samples = 0;
d_mag = 0.0;
d_input_power = 0.0;
d_num_doppler_bins = ceil( static_cast<double>(static_cast<int>(d_doppler_max) - static_cast<int>(-d_doppler_max)) / static_cast<double>(d_doppler_step));
// Create the carrier Doppler wipeoff signals
d_grid_doppler_wipeoffs = new gr_complex*[d_num_doppler_bins];
for (unsigned int doppler_index = 0; doppler_index < d_num_doppler_bins; doppler_index++)
{
d_grid_doppler_wipeoffs[doppler_index] = static_cast<gr_complex*>(volk_malloc(d_fft_size * sizeof(gr_complex), volk_get_alignment()));
int doppler = -static_cast<int>(d_doppler_max) + d_doppler_step * doppler_index;
complex_exp_gen(d_grid_doppler_wipeoffs[doppler_index], -d_freq - doppler, d_fs_in, d_fft_size);
}
}
void pcps_acquisition_sc::set_state(int state)
{
d_state = state;
if (d_state == 1)
{
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;
}
else if (d_state == 0)
{}
else
{
LOG(ERROR) << "State can only be set to 0 or 1";
}
}
int pcps_acquisition_sc::general_work(int noutput_items,
gr_vector_int &ninput_items, gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
/*
* By J.Arribas, L.Esteve and M.Molina
* Acquisition strategy (Kay Borre book + CFAR threshold):
* 1. Compute the input signal power estimation
* 2. Doppler serial search loop
* 3. Perform the FFT-based circular convolution (parallel time search)
* 4. Record the maximum peak and the associated synchronization parameters
* 5. Compute the test statistics and compare to the threshold
* 6. Declare positive or negative acquisition using a message queue
*/
int acquisition_message = -1; //0=STOP_CHANNEL 1=ACQ_SUCCEES 2=ACQ_FAIL
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;
}
d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
consume_each(ninput_items[0]);
//DLOG(INFO) << "Consumed " << ninput_items[0] << " items";
break;
}
case 1:
{
// initialize acquisition algorithm
int doppler;
unsigned int indext = 0;
float magt = 0.0;
const lv_16sc_t *in = (const lv_16sc_t *)input_items[0]; //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_sample_counter += d_fft_size; // sample counter
d_well_count++;
DLOG(INFO) << "Channel: " << d_channel
<< " , doing acquisition of satellite: " << d_gnss_synchro->System << " "<< d_gnss_synchro->PRN
<< " ,sample stamp: " << d_sample_counter << ", threshold: "
<< d_threshold << ", doppler_max: " << d_doppler_max
<< ", doppler_step: " << d_doppler_step;
// 1- 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;
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_32f_index_max_16u(&indext, d_magnitude, effective_fft_size);
// Normalize the maximum value to correct the scale factor introduced by FFTW
magt = d_magnitude[indext] / (fft_normalization_factor * fft_normalization_factor);
// 4- record the maximum peak and the associated synchronization parameters
if (d_mag < magt)
{
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_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 = d_sample_counter;
// 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)
{
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((char*)d_ifft->get_outbuf(), n); //write directly |abs(x)|^2 in this Doppler bin?
d_dump_file.close();
}
}
if (!d_bit_transition_flag)
{
if (d_test_statistics > d_threshold)
{
d_state = 2; // Positive acquisition
}
else if (d_well_count == d_max_dwells)
{
d_state = 3; // Negative acquisition
}
}
else
{
if (d_well_count == d_max_dwells) // d_max_dwells = 2
{
if (d_test_statistics > d_threshold)
{
d_state = 2; // Positive acquisition
}
else
{
d_state = 3; // Negative acquisition
}
}
}
consume_each(1);
DLOG(INFO) << "Done. Consumed 1 item.";
break;
}
case 2:
{
// 6.1- Declare positive acquisition using a message queue
DLOG(INFO) << "positive acquisition";
DLOG(INFO) << "satellite " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN;
DLOG(INFO) << "sample_stamp " << d_sample_counter;
DLOG(INFO) << "test statistics value " << d_test_statistics;
DLOG(INFO) << "test statistics threshold " << d_threshold;
DLOG(INFO) << "code phase " << d_gnss_synchro->Acq_delay_samples;
DLOG(INFO) << "doppler " << d_gnss_synchro->Acq_doppler_hz;
DLOG(INFO) << "magnitude " << d_mag;
DLOG(INFO) << "input signal power " << d_input_power;
d_active = false;
d_state = 0;
d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
consume_each(ninput_items[0]);
acquisition_message = 1;
d_channel_internal_queue->push(acquisition_message);
break;
}
case 3:
{
// 6.2- Declare negative acquisition using a message queue
DLOG(INFO) << "negative acquisition";
DLOG(INFO) << "satellite " << d_gnss_synchro->System << " " << d_gnss_synchro->PRN;
DLOG(INFO) << "sample_stamp " << d_sample_counter;
DLOG(INFO) << "test statistics value " << d_test_statistics;
DLOG(INFO) << "test statistics threshold " << d_threshold;
DLOG(INFO) << "code phase " << d_gnss_synchro->Acq_delay_samples;
DLOG(INFO) << "doppler " << d_gnss_synchro->Acq_doppler_hz;
DLOG(INFO) << "magnitude " << d_mag;
DLOG(INFO) << "input signal power " << d_input_power;
d_active = false;
d_state = 0;
d_sample_counter += d_fft_size * ninput_items[0]; // sample counter
consume_each(ninput_items[0]);
acquisition_message = 2;
d_channel_internal_queue->push(acquisition_message);
break;
}
}
output_items.clear(); // removes a warning
return noutput_items;
}
//void pcps_acquisition_sc::forecast (int noutput_items, gr_vector_int &ninput_items_required)
//{
//// COD:
//// For zero-padded case we need one extra code period
//if( d_bit_transition_flag )
//{
//ninput_items_required[0] = noutput_items*(d_samples_per_code * d_max_dwells + d_samples_per_code);
//}
//else
//{
//ninput_items_required[0] = noutput_items*d_fft_size*d_max_dwells;
//}
//}

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/*!
* \file pcps_acquisition_sc.h
* \brief This class implements a Parallel Code Phase Search Acquisition
*
* Acquisition strategy (Kay Borre book + CFAR threshold).
* <ol>
* <li> Compute the input signal power estimation
* <li> Doppler serial search loop
* <li> Perform the FFT-based circular convolution (parallel time search)
* <li> Record the maximum peak and the associated synchronization parameters
* <li> Compute the test statistics and compare to the threshold
* <li> Declare positive or negative acquisition using a message queue
* </ol>
*
* Kay Borre book: K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
* "A Software-Defined GPS and Galileo Receiver. A Single-Frequency
* Approach", Birkha user, 2007. pp 81-84
*
* \authors <ul>
* <li> Javier Arribas, 2011. jarribas(at)cttc.es
* <li> Luis Esteve, 2012. luis(at)epsilon-formacion.com
* <li> Marc Molina, 2013. marc.molina.pena@gmail.com
* </ul>
*
* -------------------------------------------------------------------------
*
* Copyright (C) 2010-2015 (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/>.
*
* -------------------------------------------------------------------------
*/
#ifndef GNSS_SDR_PCPS_ACQUISITION_SC_H_
#define GNSS_SDR_PCPS_ACQUISITION_SC_H_
#include <fstream>
#include <string>
#include <gnuradio/block.h>
#include <gnuradio/msg_queue.h>
#include <gnuradio/gr_complex.h>
#include <gnuradio/fft/fft.h>
#include "concurrent_queue.h"
#include "gnss_synchro.h"
class pcps_acquisition_sc;
typedef boost::shared_ptr<pcps_acquisition_sc> pcps_acquisition_sc_sptr;
pcps_acquisition_sc_sptr
pcps_make_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
unsigned int doppler_max, long freq, long fs_in,
int samples_per_ms, int samples_per_code,
bool bit_transition_flag,
gr::msg_queue::sptr queue, bool dump,
std::string dump_filename);
/*!
* \brief This class implements a Parallel Code Phase Search Acquisition.
*
* Check \ref Navitec2012 "An Open Source Galileo E1 Software Receiver",
* Algorithm 1, for a pseudocode description of this implementation.
*/
class pcps_acquisition_sc: public gr::block
{
private:
friend pcps_acquisition_sc_sptr
pcps_make_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
unsigned int doppler_max, long freq, long fs_in,
int samples_per_ms, int samples_per_code,
bool bit_transition_flag,
gr::msg_queue::sptr queue, bool dump,
std::string dump_filename);
pcps_acquisition_sc(unsigned int sampled_ms, unsigned int max_dwells,
unsigned int doppler_max, long freq, long fs_in,
int samples_per_ms, int samples_per_code,
bool bit_transition_flag,
gr::msg_queue::sptr queue, bool dump,
std::string dump_filename);
void calculate_magnitudes(gr_complex* fft_begin, int doppler_shift,
int doppler_offset);
long d_fs_in;
long d_freq;
int d_samples_per_ms;
int d_samples_per_code;
//unsigned int d_doppler_resolution;
float d_threshold;
std::string d_satellite_str;
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;
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;
gr::msg_queue::sptr d_queue;
concurrent_queue<int> *d_channel_internal_queue;
std::ofstream d_dump_file;
bool d_active;
int d_state;
bool d_dump;
unsigned int d_channel;
std::string d_dump_filename;
public:
/*!
* \brief Default destructor.
*/
~pcps_acquisition_sc();
/*!
* \brief Set acquisition/tracking common Gnss_Synchro object pointer
* to exchange synchronization data between acquisition and tracking blocks.
* \param p_gnss_synchro Satellite information shared by the processing blocks.
*/
void set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
{
d_gnss_synchro = p_gnss_synchro;
}
/*!
* \brief Returns the maximum peak of grid search.
*/
unsigned int mag()
{
return d_mag;
}
/*!
* \brief Initializes acquisition algorithm.
*/
void init();
/*!
* \brief Sets local code for PCPS acquisition algorithm.
* \param code - Pointer to the PRN code.
*/
void set_local_code(std::complex<float> * code);
/*!
* \brief Starts acquisition algorithm, turning from standby mode to
* active mode
* \param active - bool that activates/deactivates the block.
*/
void set_active(bool active)
{
d_active = active;
}
/*!
* \brief If set to 1, ensures that acquisition starts at the
* first available sample.
* \param state - int=1 forces start of acquisition
*/
void set_state(int state);
/*!
* \brief Set acquisition channel unique ID
* \param channel - receiver channel.
*/
void set_channel(unsigned int channel)
{
d_channel = channel;
}
/*!
* \brief Set statistics threshold of PCPS algorithm.
* \param threshold - Threshold for signal detection (check \ref Navitec2012,
* Algorithm 1, for a definition of this threshold).
*/
void set_threshold(float threshold)
{
d_threshold = threshold;
}
/*!
* \brief Set maximum Doppler grid search
* \param doppler_max - Maximum Doppler shift considered in the grid search [Hz].
*/
void set_doppler_max(unsigned int doppler_max)
{
d_doppler_max = doppler_max;
}
/*!
* \brief Set Doppler steps for the grid search
* \param doppler_step - Frequency bin of the search grid [Hz].
*/
void set_doppler_step(unsigned int doppler_step)
{
d_doppler_step = doppler_step;
}
/*!
* \brief Set tracking channel internal queue.
* \param channel_internal_queue - Channel's internal blocks information queue.
*/
void set_channel_queue(concurrent_queue<int> *channel_internal_queue)
{
d_channel_internal_queue = channel_internal_queue;
}
/*!
* \brief Parallel Code Phase Search Acquisition signal processing.
*/
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_PCPS_ACQUISITION_SC_H_*/