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Migration of Galileo E1 DLL PLL VEML tracking to use the optimized

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cpu_multicorrelator class
This commit is contained in:
Javier Arribas 2016-02-26 11:14:45 +01:00
parent b94253cb10
commit 1bafa1e447
2 changed files with 55 additions and 112 deletions
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149
src/algorithms/tracking/gnuradio_blocks/galileo_e1_dll_pll_veml_tracking_cc.cc
View File

@ -128,21 +128,33 @@ galileo_e1_dll_pll_veml_tracking_cc::galileo_e1_dll_pll_veml_tracking_cc(
// Initialization of local code replica // Initialization of local code replica
// Get space for a vector with the sinboc(1,1) replica sampled 2x/chip // Get space for a vector with the sinboc(1,1) replica sampled 2x/chip
d_ca_code = static_cast<gr_complex*>(volk_malloc((2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 4) * sizeof(gr_complex), volk_get_alignment())); d_ca_code = static_cast<gr_complex*>(volk_malloc((2*Galileo_E1_B_CODE_LENGTH_CHIPS) * sizeof(gr_complex), volk_get_alignment()));
d_very_early_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_early_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_prompt_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_late_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_very_late_code = static_cast<gr_complex*>(volk_malloc(2 * d_vector_length * sizeof(gr_complex), volk_get_alignment()));
d_carr_sign = static_cast<gr_complex*>(volk_malloc(2*d_vector_length * sizeof(gr_complex), volk_get_alignment()));
// correlator outputs (scalar) // correlator outputs (scalar)
d_Very_Early = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment())); d_n_correlator_taps = 5; // Very-Early, Early, Prompt, Late, Very-Late
d_Early = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment())); d_correlator_outs = static_cast<gr_complex*>(volk_malloc(d_n_correlator_taps*sizeof(gr_complex), volk_get_alignment()));
d_Prompt = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment())); for (int n = 0; n < d_n_correlator_taps; n++)
d_Late = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment())); {
d_Very_Late = static_cast<gr_complex*>(volk_malloc(sizeof(gr_complex), volk_get_alignment())); d_correlator_outs[n] = gr_complex(0,0);
}
// map memory pointers of correlator outputs
d_Very_Early=&d_correlator_outs[0];
d_Early=&d_correlator_outs[1];
d_Prompt=&d_correlator_outs[2];
d_Late=&d_correlator_outs[3];
d_Very_Late=&d_correlator_outs[4];
d_local_code_shift_chips = static_cast<float*>(volk_malloc(d_n_correlator_taps*sizeof(float), volk_get_alignment()));
// Set TAPs delay values [chips]
d_local_code_shift_chips[0] = - d_very_early_late_spc_chips*2.0;
d_local_code_shift_chips[1] = - d_very_early_late_spc_chips;
d_local_code_shift_chips[2] = 0.0;
d_local_code_shift_chips[3] = d_very_early_late_spc_chips;
d_local_code_shift_chips[4] = d_very_early_late_spc_chips*2.0;
d_correlation_length_samples=d_vector_length;
multicorrelator_cpu.init(2 * d_correlation_length_samples, d_n_correlator_taps);
//--- Initializations ------------------------------ //--- Initializations ------------------------------
// Initial code frequency basis of NCO // Initial code frequency basis of NCO
@ -198,18 +210,19 @@ void galileo_e1_dll_pll_veml_tracking_cc::start_tracking()
d_carrier_loop_filter.initialize(); // initialize the carrier filter d_carrier_loop_filter.initialize(); // initialize the carrier filter
d_code_loop_filter.initialize(); // initialize the code filter d_code_loop_filter.initialize(); // initialize the code filter
// generate local reference ALWAYS starting at chip 2 (2 samples per chip) // generate local reference ALWAYS starting at chip 1 (2 samples per chip)
galileo_e1_code_gen_complex_sampled(&d_ca_code[2], galileo_e1_code_gen_complex_sampled(d_ca_code,
d_acquisition_gnss_synchro->Signal, d_acquisition_gnss_synchro->Signal,
false, false,
d_acquisition_gnss_synchro->PRN, d_acquisition_gnss_synchro->PRN,
2 * Galileo_E1_CODE_CHIP_RATE_HZ, 2 * Galileo_E1_CODE_CHIP_RATE_HZ,
0); 0);
// Fill head and tail
d_ca_code[0] = d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS)]; multicorrelator_cpu.set_local_code_and_taps(static_cast<int>(2*Galileo_E1_B_CODE_LENGTH_CHIPS), d_ca_code, d_local_code_shift_chips);
d_ca_code[1] = d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 1)]; for (int n = 0; n < d_n_correlator_taps; n++)
d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 2)] = d_ca_code[2]; {
d_ca_code[static_cast<int>(2 * Galileo_E1_B_CODE_LENGTH_CHIPS + 3)] = d_ca_code[3]; d_correlator_outs[n] = gr_complex(0,0);
}
d_carrier_lock_fail_counter = 0; d_carrier_lock_fail_counter = 0;
d_rem_code_phase_samples = 0.0; d_rem_code_phase_samples = 0.0;
@ -235,77 +248,16 @@ void galileo_e1_dll_pll_veml_tracking_cc::start_tracking()
<< " PULL-IN Code Phase [samples]=" << d_acq_code_phase_samples; << " PULL-IN Code Phase [samples]=" << d_acq_code_phase_samples;
} }
void galileo_e1_dll_pll_veml_tracking_cc::update_local_code()
{
double tcode_half_chips;
double rem_code_phase_half_chips;
int associated_chip_index;
int code_length_half_chips = static_cast<int>(Galileo_E1_B_CODE_LENGTH_CHIPS) * 2;
double code_phase_step_chips;
double code_phase_step_half_chips;
int early_late_spc_samples;
int very_early_late_spc_samples;
int epl_loop_length_samples;
// unified loop for VE, E, P, L, VL code vectors
code_phase_step_chips = d_code_freq_chips / (static_cast<double>(d_fs_in));
code_phase_step_half_chips = (2.0 * d_code_freq_chips) / (static_cast<double>(d_fs_in));
rem_code_phase_half_chips = d_rem_code_phase_samples * (2*d_code_freq_chips / d_fs_in);
tcode_half_chips = - rem_code_phase_half_chips;
early_late_spc_samples = std::round(d_early_late_spc_chips / code_phase_step_chips);
very_early_late_spc_samples = std::round(d_very_early_late_spc_chips / code_phase_step_chips);
epl_loop_length_samples = d_current_prn_length_samples + very_early_late_spc_samples * 2;
for (int i = 0; i < epl_loop_length_samples; i++)
{
associated_chip_index = 2 + std::round(std::fmod(tcode_half_chips - 2 * d_very_early_late_spc_chips, code_length_half_chips));
d_very_early_code[i] = d_ca_code[associated_chip_index];
tcode_half_chips = tcode_half_chips + code_phase_step_half_chips;
}
memcpy(d_early_code, &d_very_early_code[very_early_late_spc_samples - early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_prompt_code, &d_very_early_code[very_early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_late_code, &d_very_early_code[very_early_late_spc_samples + early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
memcpy(d_very_late_code, &d_very_early_code[2 * very_early_late_spc_samples], d_current_prn_length_samples * sizeof(gr_complex));
}
void galileo_e1_dll_pll_veml_tracking_cc::update_local_carrier()
{
float sin_f, cos_f;
float phase_step_rad = static_cast<float>(2 * GALILEO_PI) * d_carrier_doppler_hz / static_cast<float>(d_fs_in);
int phase_step_rad_i = gr::fxpt::float_to_fixed(phase_step_rad);
int phase_rad_i = gr::fxpt::float_to_fixed(d_rem_carr_phase_rad);
for(int i = 0; i < d_current_prn_length_samples; i++)
{
gr::fxpt::sincos(phase_rad_i, &sin_f, &cos_f);
d_carr_sign[i] = std::complex<float>(cos_f, -sin_f);
phase_rad_i += phase_step_rad_i;
}
}
galileo_e1_dll_pll_veml_tracking_cc::~galileo_e1_dll_pll_veml_tracking_cc() galileo_e1_dll_pll_veml_tracking_cc::~galileo_e1_dll_pll_veml_tracking_cc()
{ {
d_dump_file.close(); d_dump_file.close();
volk_free(d_very_early_code); volk_free(d_local_code_shift_chips);
volk_free(d_early_code); volk_free(d_correlator_outs);
volk_free(d_prompt_code);
volk_free(d_late_code);
volk_free(d_very_late_code);
volk_free(d_carr_sign);
volk_free(d_Very_Early);
volk_free(d_Early);
volk_free(d_Prompt);
volk_free(d_Late);
volk_free(d_Very_Late);
volk_free(d_ca_code); volk_free(d_ca_code);
delete[] d_Prompt_buffer; delete[] d_Prompt_buffer;
multicorrelator_cpu.free();
} }
@ -346,24 +298,19 @@ int galileo_e1_dll_pll_veml_tracking_cc::general_work (int noutput_items, gr_vec
const gr_complex* in = (gr_complex*) input_items[0]; const gr_complex* in = (gr_complex*) input_items[0];
Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0]; Gnss_Synchro **out = (Gnss_Synchro **) &output_items[0];
// Generate local code and carrier replicas (using \hat{f}_d(k-1)) // ################# CARRIER WIPEOFF AND CORRELATORS ##############################
update_local_code(); // perform carrier wipe-off and compute Early, Prompt and Late correlation
update_local_carrier(); multicorrelator_cpu.set_input_output_vectors(d_correlator_outs,in);
// perform carrier wipe-off and compute Very Early, Early, Prompt, Late and Very Late correlation double carr_phase_step_rad = GALILEO_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
d_correlator.Carrier_wipeoff_and_VEPL_volk(d_current_prn_length_samples, double code_phase_step_half_chips = (2.0 * d_code_freq_chips) / (static_cast<double>(d_fs_in));
in, double rem_code_phase_half_chips = d_rem_code_phase_samples * (2.0*d_code_freq_chips / d_fs_in);
d_carr_sign, multicorrelator_cpu.Carrier_wipeoff_multicorrelator_resampler(
d_very_early_code, d_rem_carr_phase_rad,
d_early_code, carr_phase_step_rad,
d_prompt_code, rem_code_phase_half_chips,
d_late_code, code_phase_step_half_chips,
d_very_late_code, d_correlation_length_samples);
d_Very_Early,
d_Early,
d_Prompt,
d_Late,
d_Very_Late);
// ################## PLL ########################################################## // ################## PLL ##########################################################
// PLL discriminator // PLL discriminator

18
src/algorithms/tracking/gnuradio_blocks/galileo_e1_dll_pll_veml_tracking_cc.h
View File

@ -41,7 +41,7 @@
#include "gnss_synchro.h" #include "gnss_synchro.h"
#include "tracking_2nd_DLL_filter.h" #include "tracking_2nd_DLL_filter.h"
#include "tracking_2nd_PLL_filter.h" #include "tracking_2nd_PLL_filter.h"
#include "correlator.h" #include "cpu_multicorrelator.h"
class galileo_e1_dll_pll_veml_tracking_cc; class galileo_e1_dll_pll_veml_tracking_cc;
@ -123,17 +123,16 @@ private:
long d_if_freq; long d_if_freq;
long d_fs_in; long d_fs_in;
//Integration period in samples
int d_correlation_length_samples;
int d_n_correlator_taps;
double d_early_late_spc_chips; double d_early_late_spc_chips;
double d_very_early_late_spc_chips; double d_very_early_late_spc_chips;
gr_complex* d_ca_code; gr_complex* d_ca_code;
float* d_local_code_shift_chips;
gr_complex* d_very_early_code; gr_complex* d_correlator_outs;
gr_complex* d_early_code; cpu_multicorrelator multicorrelator_cpu;
gr_complex* d_prompt_code;
gr_complex* d_late_code;
gr_complex* d_very_late_code;
gr_complex* d_carr_sign;
gr_complex *d_Very_Early; gr_complex *d_Very_Early;
gr_complex *d_Early; gr_complex *d_Early;
@ -153,9 +152,6 @@ private:
double d_acq_code_phase_samples; double d_acq_code_phase_samples;
double d_acq_carrier_doppler_hz; double d_acq_carrier_doppler_hz;
// correlator
Correlator d_correlator;
// tracking vars // tracking vars
double d_code_freq_chips; double d_code_freq_chips;
double d_carrier_doppler_hz; double d_carrier_doppler_hz;