[hamradio-commits] [gnss-sdr] 91/149: Added native input sample interface support for 16 bits integer complex in PCPS_Acquisition (added the _sc variant). Now the PCPS acquisiton adapter requires no conversion when the receiver works with 16 bits integer complex samples.
Carles Fernandez
carles_fernandez-guest at moszumanska.debian.org
Sat Feb 6 19:43:06 UTC 2016
This is an automated email from the git hooks/post-receive script.
carles_fernandez-guest pushed a commit to branch next
in repository gnss-sdr.
commit ea35f33c8398667215a5d2506bb667c6a96bcc26
Author: Javier Arribas <javiarribas at gmail.com>
Date: Wed Jan 20 18:24:03 2016 +0100
Added native input sample interface support for 16 bits integer complex
in PCPS_Acquisition (added the _sc variant). Now the PCPS acquisiton
adapter requires no conversion when the receiver works with 16 bits
integer complex samples.
---
src/algorithms/acquisition/adapters/CMakeLists.txt | 1 +
.../adapters/gps_l1_ca_pcps_acquisition.cc | 184 ++++----
.../adapters/gps_l1_ca_pcps_acquisition.h | 3 +
.../acquisition/gnuradio_blocks/CMakeLists.txt | 4 +-
.../gnuradio_blocks/pcps_acquisition_sc.cc | 472 +++++++++++++++++++++
.../gnuradio_blocks/pcps_acquisition_sc.h | 244 +++++++++++
6 files changed, 836 insertions(+), 72 deletions(-)
diff --git a/src/algorithms/acquisition/adapters/CMakeLists.txt b/src/algorithms/acquisition/adapters/CMakeLists.txt
index e72f05f..5d27297 100644
--- a/src/algorithms/acquisition/adapters/CMakeLists.txt
+++ b/src/algorithms/acquisition/adapters/CMakeLists.txt
@@ -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")
diff --git a/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc b/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc
index 196450f..3cda828 100644
--- a/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc
+++ b/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.cc
@@ -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_;
+ }
}
diff --git a/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h b/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h
index 5266594..3fd8db7 100644
--- a/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h
+++ b/src/algorithms/acquisition/adapters/gps_l1_ca_pcps_acquisition.h
@@ -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_;
diff --git a/src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt b/src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt
index 5a1d0d5..b75be3c 100644
--- a/src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt
+++ b/src/algorithms/acquisition/gnuradio_blocks/CMakeLists.txt
@@ -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})
diff --git a/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc b/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc
new file mode 100644
index 0000000..2648ad5
--- /dev/null
+++ b/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.cc
@@ -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 at 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;
+ //}
+//}
diff --git a/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.h b/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.h
new file mode 100644
index 0000000..7270d78
--- /dev/null
+++ b/src/algorithms/acquisition/gnuradio_blocks/pcps_acquisition_sc.h
@@ -0,0 +1,244 @@
+/*!
+ * \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 at 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_*/
--
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