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Code Issues Releases Wiki Activity

Minor fixes

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This commit is contained in:
Carles Fernandez 2018-03-29 09:23:23 +02:00
parent b3764f6ed1
commit 539e24f0ac
2 changed files with 313 additions and 319 deletions
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613
src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking.cc
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@ -1,7 +1,7 @@
/*! /*!
* \file dll_pll_veml_tracking.cc * \file dll_pll_veml_tracking.cc
* \brief Implementation of a code DLL + carrier PLL tracking block. * \brief Implementation of a code DLL + carrier PLL tracking block.
* \author Antonio Ramos, 2018 antonioramosdet(at)gmail.com * \author Antonio Ramos, 2018 antonio.ramosdet(at)gmail.com
* *
* Code DLL + carrier PLL according to the algorithms described in: * Code DLL + carrier PLL according to the algorithms described in:
* [1] K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen, * [1] K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
@ -112,7 +112,8 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
float pll_bw_narrow_hz, float dll_bw_narrow_hz, float pll_bw_narrow_hz, float dll_bw_narrow_hz,
float early_late_space_chips, float very_early_late_space_chips, float early_late_space_chips, float very_early_late_space_chips,
float early_late_space_narrow_chips, float very_early_late_space_narrow_chips, float early_late_space_narrow_chips, float very_early_late_space_narrow_chips,
int extend_correlation_symbols, bool track_pilot, char system, char signal[3]) : gr::block("dll_pll_veml_tracking", gr::io_signature::make(1, 1, sizeof(gr_complex)), int extend_correlation_symbols, bool track_pilot, char system,
char signal[3]) : gr::block("dll_pll_veml_tracking", gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(Gnss_Synchro))) gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{ {
// Telemetry bit synchronization message port input // Telemetry bit synchronization message port input
@ -145,7 +146,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_correlation_length_ms = 1; d_correlation_length_ms = 1;
d_code_samples_per_chip = 1; d_code_samples_per_chip = 1;
d_code_length_chips = static_cast<unsigned int>(GPS_L1_CA_CODE_LENGTH_CHIPS); d_code_length_chips = static_cast<unsigned int>(GPS_L1_CA_CODE_LENGTH_CHIPS);
//GPS L1 C/A does not have pilot component nor secondary code // GPS L1 C/A does not have pilot component nor secondary code
d_secondary = false; d_secondary = false;
d_track_pilot = false; d_track_pilot = false;
interchange_iq = false; interchange_iq = false;
@ -159,7 +160,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_symbols_per_bit = GPS_L2_SAMPLES_PER_SYMBOL; d_symbols_per_bit = GPS_L2_SAMPLES_PER_SYMBOL;
d_correlation_length_ms = 20; d_correlation_length_ms = 20;
d_code_samples_per_chip = 1; d_code_samples_per_chip = 1;
//GPS L2 does not have pilot component nor secondary code // GPS L2 does not have pilot component nor secondary code
d_secondary = false; d_secondary = false;
d_track_pilot = false; d_track_pilot = false;
interchange_iq = false; interchange_iq = false;
@ -173,7 +174,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
d_correlation_length_ms = 1; d_correlation_length_ms = 1;
d_code_samples_per_chip = 1; d_code_samples_per_chip = 1;
d_code_length_chips = static_cast<unsigned int>(GPS_L5i_CODE_LENGTH_CHIPS); d_code_length_chips = static_cast<unsigned int>(GPS_L5i_CODE_LENGTH_CHIPS);
//GPS L5 does not have pilot secondary code // GPS L5 does not have pilot secondary code
d_secondary = true; d_secondary = true;
if (d_track_pilot) if (d_track_pilot)
{ {
@ -191,7 +192,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
else else
{ {
LOG(WARNING) << "Invalid Signal argument when instantiating tracking blocks"; LOG(WARNING) << "Invalid Signal argument when instantiating tracking blocks";
std::cout << "Invalid Signal argument when instantiating tracking blocks" << std::endl; std::cerr << "Invalid Signal argument when instantiating tracking blocks" << std::endl;
} }
} }
else if (system == 'E') else if (system == 'E')
@ -250,7 +251,7 @@ dll_pll_veml_tracking::dll_pll_veml_tracking(
else else
{ {
LOG(WARNING) << "Invalid System argument when instantiating tracking blocks"; LOG(WARNING) << "Invalid System argument when instantiating tracking blocks";
std::cout << "Invalid System argument when instantiating tracking blocks" << std::endl; std::cerr << "Invalid System argument when instantiating tracking blocks" << std::endl;
d_correlation_length_ms = 1; d_correlation_length_ms = 1;
d_secondary = false; d_secondary = false;
interchange_iq = false; interchange_iq = false;
@ -411,12 +412,11 @@ void dll_pll_veml_tracking::start_tracking()
d_acq_carrier_doppler_hz = d_acquisition_gnss_synchro->Acq_doppler_hz; d_acq_carrier_doppler_hz = d_acquisition_gnss_synchro->Acq_doppler_hz;
d_acq_sample_stamp = d_acquisition_gnss_synchro->Acq_samplestamp_samples; d_acq_sample_stamp = d_acquisition_gnss_synchro->Acq_samplestamp_samples;
long int acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp); //-d_vector_length; long int acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp);
double acq_trk_diff_seconds = static_cast<double>(acq_trk_diff_samples) / d_fs_in; double acq_trk_diff_seconds = static_cast<double>(acq_trk_diff_samples) / d_fs_in;
DLOG(INFO) << "Number of samples between Acquisition and Tracking = " << acq_trk_diff_samples; DLOG(INFO) << "Number of samples between Acquisition and Tracking = " << acq_trk_diff_samples;
DLOG(INFO) << "Number of seconds between Acquisition and Tracking = " << acq_trk_diff_seconds; DLOG(INFO) << "Number of seconds between Acquisition and Tracking = " << acq_trk_diff_seconds;
// Doppler effect // Doppler effect Fd = (C / (C + Vr)) * F
// Fd=(C/(C+Vr))*F
double radial_velocity = (d_signal_carrier_freq + d_acq_carrier_doppler_hz) / d_signal_carrier_freq; double radial_velocity = (d_signal_carrier_freq + d_acq_carrier_doppler_hz) / d_signal_carrier_freq;
// new chip and prn sequence periods based on acq Doppler // new chip and prn sequence periods based on acq Doppler
d_code_freq_chips = radial_velocity * d_code_chip_rate; d_code_freq_chips = radial_velocity * d_code_chip_rate;
@ -604,7 +604,7 @@ dll_pll_veml_tracking::~dll_pll_veml_tracking()
bool dll_pll_veml_tracking::acquire_secondary() bool dll_pll_veml_tracking::acquire_secondary()
{ {
//******* preamble correlation ******** // ******* preamble correlation ********
int corr_value = 0; int corr_value = 0;
for (unsigned int i = 0; i < d_secondary_code_length; i++) for (unsigned int i = 0; i < d_secondary_code_length; i++)
{ {
@ -766,6 +766,7 @@ void dll_pll_veml_tracking::clear_tracking_vars()
d_last_prompt = gr_complex(0.0, 0.0); d_last_prompt = gr_complex(0.0, 0.0);
} }
void dll_pll_veml_tracking::update_tracking_vars() void dll_pll_veml_tracking::update_tracking_vars()
{ {
T_chip_seconds = 1.0 / d_code_freq_chips; T_chip_seconds = 1.0 / d_code_freq_chips;
@ -796,6 +797,7 @@ void dll_pll_veml_tracking::update_tracking_vars()
d_rem_code_phase_chips = d_code_freq_chips * d_rem_code_phase_samples / d_fs_in; d_rem_code_phase_chips = d_code_freq_chips * d_rem_code_phase_samples / d_fs_in;
} }
void dll_pll_veml_tracking::save_correlation_results() void dll_pll_veml_tracking::save_correlation_results()
{ {
if (d_secondary) if (d_secondary)
@ -960,301 +962,6 @@ void dll_pll_veml_tracking::log_data(bool integrating)
} }
int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
gr::thread::scoped_lock l(d_setlock);
const gr_complex *in = reinterpret_cast<const gr_complex *>(input_items[0]);
Gnss_Synchro **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);
Gnss_Synchro current_synchro_data = Gnss_Synchro();
switch (d_state)
{
case 0: // Standby - Pass Through. Full throttle
{
d_sample_counter += ninput_items[0];
consume_each(ninput_items[0]);
return 0;
break;
}
case 1: // Pull-in
{
// Signal alignment (skip samples until the incoming signal is aligned with local replica)
// Fill the acquisition data
unsigned long int acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp;
double acq_trk_shif_correction_samples = static_cast<double>(d_current_prn_length_samples) - std::fmod(static_cast<double>(acq_to_trk_delay_samples), static_cast<double>(d_current_prn_length_samples));
int samples_offset = std::round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
if (samples_offset < 0)
{
samples_offset = 0;
}
d_acc_carrier_phase_rad -= d_carrier_phase_step_rad * d_acq_code_phase_samples;
d_state = 2;
d_sample_counter += samples_offset; // count for the processed samples
consume_each(samples_offset); // shift input to perform alignment with local replica
return 0;
}
case 2: // Wide tracking and symbol synchronization
{
do_correlation_step(in);
// Save single correlation step variables
if (d_veml)
{
d_VE_accu = *d_Very_Early;
d_VL_accu = *d_Very_Late;
}
d_E_accu = *d_Early;
d_P_accu = *d_Prompt;
d_L_accu = *d_Late;
// Check lock status
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
}
else
{
bool next_state = false;
// Perform DLL/PLL tracking loop computations. Costas Loop enabled
run_dll_pll();
update_tracking_vars();
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data(false);
if (d_secondary)
{
// ####### SECONDARY CODE LOCK #####
d_Prompt_buffer_deque.push_back(*d_Prompt);
if (d_Prompt_buffer_deque.size() == d_secondary_code_length)
{
next_state = acquire_secondary();
if (next_state)
{
std::cout << "Secondary code locked for CH " << d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
}
d_Prompt_buffer_deque.pop_front();
}
}
else //Signal does not have secondary code. Search a bit transition by sign change
{
if (d_synchonizing)
{
if (d_Prompt->real() * d_last_prompt.real() > 0.0)
{
d_current_symbol++;
}
else if (d_current_symbol > d_symbols_per_bit)
{
d_synchonizing = false;
d_current_symbol = 1;
}
else
{
d_current_symbol = 1;
d_last_prompt = *d_Prompt;
}
}
else if (d_last_prompt.real() != 0.0)
{
d_current_symbol++;
if (d_current_symbol == d_symbols_per_bit) next_state = true;
}
else
{
d_last_prompt = *d_Prompt;
d_synchonizing = true;
d_current_symbol = 1;
}
}
if (next_state)
{ // reset extended correlator
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
d_last_prompt = gr_complex(0.0, 0.0);
d_Prompt_buffer_deque.clear();
d_current_symbol = 0;
d_synchonizing = false;
// Set narrow taps delay values [chips]
d_code_loop_filter.set_DLL_BW(d_dll_bw_narrow_hz);
d_carrier_loop_filter.set_PLL_BW(d_pll_bw_narrow_hz);
if (d_veml)
{
d_local_code_shift_chips[0] = -d_very_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[1] = -d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[3] = d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[4] = d_very_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
}
else
{
d_local_code_shift_chips[0] = -d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[2] = d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
}
// UPDATE INTEGRATION TIME
if (d_enable_extended_integration)
{
d_extend_correlation_symbols_count = 0;
float new_correlation_time_s = static_cast<float>(d_extend_correlation_symbols) * static_cast<float>(d_code_period);
d_carrier_loop_filter.set_pdi(new_correlation_time_s);
d_code_loop_filter.set_pdi(new_correlation_time_s);
d_state = 3; // next state is the extended correlator integrator
LOG(INFO) << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN);
std::cout << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
}
else
{
d_state = 4;
}
}
}
break;
}
case 3: // coherent integration (correlation time extension)
{
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// perform a correlation step
do_correlation_step(in);
update_tracking_vars();
save_correlation_results();
// ########### Output the tracking results to Telemetry block ##########
if (interchange_iq)
{
if (d_track_pilot)
{
//Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).real());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).real());
}
}
else
{
if (d_track_pilot)
{
//Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
}
}
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
d_extend_correlation_symbols_count++;
if (d_extend_correlation_symbols_count == (d_extend_correlation_symbols - 1))
{
d_extend_correlation_symbols_count = 0;
d_state = 4;
}
log_data(true);
break;
}
case 4: // narrow tracking
{
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// perform a correlation step
do_correlation_step(in);
save_correlation_results();
// check lock status
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
}
else
{
run_dll_pll();
update_tracking_vars();
// ########### Output the tracking results to Telemetry block ##########
if (interchange_iq)
{
if (d_track_pilot)
{
//Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).real());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).real());
}
}
else
{
if (d_track_pilot)
{
//Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
}
}
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data(false);
// reset extended correlator
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
if (d_enable_extended_integration)
{
d_state = 3; //new coherent integration (correlation time extension) cycle
}
}
}
}
consume_each(d_current_prn_length_samples);
d_sample_counter += d_current_prn_length_samples;
if (current_synchro_data.Flag_valid_symbol_output)
{
current_synchro_data.fs = static_cast<long int>(d_fs_in);
current_synchro_data.Tracking_sample_counter = d_sample_counter;
*out[0] = current_synchro_data;
return 1;
}
return 0;
}
int dll_pll_veml_tracking::save_matfile() int dll_pll_veml_tracking::save_matfile()
{ {
// READ DUMP FILE // READ DUMP FILE
@ -1510,3 +1217,297 @@ void dll_pll_veml_tracking::set_gnss_synchro(Gnss_Synchro *p_gnss_synchro)
gr::thread::scoped_lock l(d_setlock); gr::thread::scoped_lock l(d_setlock);
d_acquisition_gnss_synchro = p_gnss_synchro; d_acquisition_gnss_synchro = p_gnss_synchro;
} }
int dll_pll_veml_tracking::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
gr::thread::scoped_lock l(d_setlock);
const gr_complex *in = reinterpret_cast<const gr_complex *>(input_items[0]);
Gnss_Synchro **out = reinterpret_cast<Gnss_Synchro **>(&output_items[0]);
Gnss_Synchro current_synchro_data = Gnss_Synchro();
switch (d_state)
{
case 0: // Standby - Consume samples at full throttle, do nothing
{
d_sample_counter += ninput_items[0];
consume_each(ninput_items[0]);
return 0;
break;
}
case 1: // Pull-in
{
// Signal alignment (skip samples until the incoming signal is aligned with local replica)
unsigned long int acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp;
double acq_trk_shif_correction_samples = static_cast<double>(d_current_prn_length_samples) - std::fmod(static_cast<double>(acq_to_trk_delay_samples), static_cast<double>(d_current_prn_length_samples));
int samples_offset = std::round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
if (samples_offset < 0)
{
samples_offset = 0;
}
d_acc_carrier_phase_rad -= d_carrier_phase_step_rad * d_acq_code_phase_samples;
d_state = 2;
d_sample_counter += samples_offset; // count for the processed samples
consume_each(samples_offset); // shift input to perform alignment with local replica
return 0;
}
case 2: // Wide tracking and symbol synchronization
{
do_correlation_step(in);
// Save single correlation step variables
if (d_veml)
{
d_VE_accu = *d_Very_Early;
d_VL_accu = *d_Very_Late;
}
d_E_accu = *d_Early;
d_P_accu = *d_Prompt;
d_L_accu = *d_Late;
// Check lock status
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
}
else
{
bool next_state = false;
// Perform DLL/PLL tracking loop computations. Costas Loop enabled
run_dll_pll();
update_tracking_vars();
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data(false);
if (d_secondary)
{
// ####### SECONDARY CODE LOCK #####
d_Prompt_buffer_deque.push_back(*d_Prompt);
if (d_Prompt_buffer_deque.size() == d_secondary_code_length)
{
next_state = acquire_secondary();
if (next_state)
{
std::cout << "Secondary code locked for CH " << d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
}
d_Prompt_buffer_deque.pop_front();
}
}
else // Signal does not have secondary code. Search a bit transition by sign change
{
if (d_synchonizing)
{
if (d_Prompt->real() * d_last_prompt.real() > 0.0)
{
d_current_symbol++;
}
else if (d_current_symbol > d_symbols_per_bit)
{
d_synchonizing = false;
d_current_symbol = 1;
}
else
{
d_current_symbol = 1;
d_last_prompt = *d_Prompt;
}
}
else if (d_last_prompt.real() != 0.0)
{
d_current_symbol++;
if (d_current_symbol == d_symbols_per_bit) next_state = true;
}
else
{
d_last_prompt = *d_Prompt;
d_synchonizing = true;
d_current_symbol = 1;
}
}
if (next_state)
{ // reset extended correlator
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
d_last_prompt = gr_complex(0.0, 0.0);
d_Prompt_buffer_deque.clear();
d_current_symbol = 0;
d_synchonizing = false;
// Set narrow taps delay values [chips]
d_code_loop_filter.set_DLL_BW(d_dll_bw_narrow_hz);
d_carrier_loop_filter.set_PLL_BW(d_pll_bw_narrow_hz);
if (d_veml)
{
d_local_code_shift_chips[0] = -d_very_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[1] = -d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[3] = d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[4] = d_very_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
}
else
{
d_local_code_shift_chips[0] = -d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
d_local_code_shift_chips[2] = d_early_late_spc_narrow_chips * static_cast<float>(d_code_samples_per_chip);
}
// UPDATE INTEGRATION TIME
if (d_enable_extended_integration)
{
d_extend_correlation_symbols_count = 0;
float new_correlation_time_s = static_cast<float>(d_extend_correlation_symbols) * static_cast<float>(d_code_period);
d_carrier_loop_filter.set_pdi(new_correlation_time_s);
d_code_loop_filter.set_pdi(new_correlation_time_s);
d_state = 3; // next state is the extended correlator integrator
LOG(INFO) << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN);
std::cout << "Enabled " << d_extend_correlation_symbols << " [symbols] extended correlator for CH "
<< d_channel
<< " : Satellite " << Gnss_Satellite(systemName, d_acquisition_gnss_synchro->PRN) << std::endl;
}
else
{
d_state = 4;
}
}
}
break;
}
case 3: // coherent integration (correlation time extension)
{
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// perform a correlation step
do_correlation_step(in);
update_tracking_vars();
save_correlation_results();
// ########### Output the tracking results to Telemetry block ##########
if (interchange_iq)
{
if (d_track_pilot)
{
// Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).real());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).real());
}
}
else
{
if (d_track_pilot)
{
// Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
}
}
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
d_extend_correlation_symbols_count++;
if (d_extend_correlation_symbols_count == (d_extend_correlation_symbols - 1))
{
d_extend_correlation_symbols_count = 0;
d_state = 4;
}
log_data(true);
break;
}
case 4: // narrow tracking
{
// Fill the acquisition data
current_synchro_data = *d_acquisition_gnss_synchro;
// perform a correlation step
do_correlation_step(in);
save_correlation_results();
// check lock status
if (!cn0_and_tracking_lock_status())
{
clear_tracking_vars();
d_state = 0; // loss-of-lock detected
}
else
{
run_dll_pll();
update_tracking_vars();
// ########### Output the tracking results to Telemetry block ##########
if (interchange_iq)
{
if (d_track_pilot)
{
// Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).real());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).imag());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).real());
}
}
else
{
if (d_track_pilot)
{
// Note that data and pilot components are in quadrature. I and Q are interchanged
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt_Data).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt_Data).imag());
}
else
{
current_synchro_data.Prompt_I = static_cast<double>((*d_Prompt).real());
current_synchro_data.Prompt_Q = static_cast<double>((*d_Prompt).imag());
}
}
current_synchro_data.Code_phase_samples = d_rem_code_phase_samples;
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
current_synchro_data.CN0_dB_hz = d_CN0_SNV_dB_Hz;
current_synchro_data.Flag_valid_symbol_output = true;
current_synchro_data.correlation_length_ms = d_correlation_length_ms;
// enable write dump file this cycle (valid DLL/PLL cycle)
log_data(false);
// reset extended correlator
d_VE_accu = gr_complex(0.0, 0.0);
d_E_accu = gr_complex(0.0, 0.0);
d_P_accu = gr_complex(0.0, 0.0);
d_L_accu = gr_complex(0.0, 0.0);
d_VL_accu = gr_complex(0.0, 0.0);
if (d_enable_extended_integration)
{
d_state = 3; // new coherent integration (correlation time extension) cycle
}
}
}
}
consume_each(d_current_prn_length_samples);
d_sample_counter += d_current_prn_length_samples;
if (current_synchro_data.Flag_valid_symbol_output)
{
current_synchro_data.fs = static_cast<long int>(d_fs_in);
current_synchro_data.Tracking_sample_counter = d_sample_counter;
*out[0] = current_synchro_data;
return 1;
}
return 0;
}

17
src/algorithms/tracking/gnuradio_blocks/dll_pll_veml_tracking.h
View File

@ -1,7 +1,7 @@
/*! /*!
* \file dll_pll_veml_tracking.h * \file dll_pll_veml_tracking.h
* \brief Implementation of a code DLL + carrier PLL tracking block. * \brief Implementation of a code DLL + carrier PLL tracking block.
* \author Antonio Ramos, 2018 antonioramosdet(at)gmail.com * \author Antonio Ramos, 2018 antonio.ramosdet(at)gmail.com
* *
* ------------------------------------------------------------------------- * -------------------------------------------------------------------------
* *
@ -55,8 +55,7 @@ dll_pll_veml_tracking_sptr dll_pll_veml_make_tracking(double fs_in, unsigned int
char system, char signal[3]); char system, char signal[3]);
/*! /*!
* \brief This class implements a code DLL + carrier PLL VEML (Very Early * \brief This class implements a code DLL + carrier PLL tracking block.
* Minus Late) tracking block for Galileo E1 signals
*/ */
class dll_pll_veml_tracking : public gr::block class dll_pll_veml_tracking : public gr::block
{ {
@ -67,12 +66,6 @@ public:
void set_gnss_synchro(Gnss_Synchro *p_gnss_synchro); void set_gnss_synchro(Gnss_Synchro *p_gnss_synchro);
void start_tracking(); void start_tracking();
/*!
* \brief Code DLL + carrier PLL according to the algorithms described in:
* K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
* A Software-Defined GPS and Galileo Receiver. A Single-Frequency Approach,
* Birkhauser, 2007
*/
int general_work(int noutput_items, gr_vector_int &ninput_items, int general_work(int noutput_items, gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items); gr_vector_const_void_star &input_items, gr_vector_void_star &output_items);
@ -214,9 +207,9 @@ private:
double T_prn_seconds; double T_prn_seconds;
double T_prn_samples; double T_prn_samples;
double K_blk_samples; double K_blk_samples;
//PRN period in samples // PRN period in samples
int d_current_prn_length_samples; int d_current_prn_length_samples;
//processing samples counters // processing samples counters
unsigned long int d_sample_counter; unsigned long int d_sample_counter;
unsigned long int d_acq_sample_stamp; unsigned long int d_acq_sample_stamp;
@ -234,4 +227,4 @@ private:
std::ofstream d_dump_file; std::ofstream d_dump_file;
}; };
#endif //GNSS_SDR_DLL_PLL_VEML_TRACKING_H #endif // GNSS_SDR_DLL_PLL_VEML_TRACKING_H