mirrors/gnss-sdr
1
0
Fork 0
mirror of https://github.com/gnss-sdr/gnss-sdr synced 2025-11-03 00:33:03 +00:00
Code Issues Releases Wiki Activity

Some code cleaning

Browse Source 
git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@120 64b25241-fba3-4117-9849-534c7e92360d
This commit is contained in:
Carles Fernandez
2012-01-11 09:01:24 +00:00
parent dab517aff0
commit bc62d8d5be
16 changed files with 1052 additions and 979 deletions
Download Patch File Download Diff File Expand all files Collapse all files

861
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.cc
View File

@@ -64,205 +64,221 @@ using google::LogMessage;
gps_l1_ca_dll_pll_tracking_cc_sptr
gps_l1_ca_dll_pll_make_tracking_cc(unsigned int satellite, long if_freq, long fs_in, unsigned
int vector_length, gr_msg_queue_sptr queue, bool dump, std::string dump_filename, float pll_bw_hz, float dll_bw_hz, float early_late_space_chips) {
int vector_length, gr_msg_queue_sptr queue, bool dump, std::string dump_filename, float pll_bw_hz, float dll_bw_hz, float early_late_space_chips)
{
return gps_l1_ca_dll_pll_tracking_cc_sptr(new gps_l1_ca_dll_pll_tracking_cc(satellite, if_freq,
fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
}
void gps_l1_ca_dll_pll_tracking_cc::forecast (int noutput_items,
gr_vector_int &ninput_items_required){
ninput_items_required[0] =(int)d_vector_length*2; //set the required available samples in each call
gr_vector_int &ninput_items_required)
{
ninput_items_required[0] = (int)d_vector_length*2; //set the required available samples in each call
}
gps_l1_ca_dll_pll_tracking_cc::gps_l1_ca_dll_pll_tracking_cc(unsigned int satellite, long if_freq, long fs_in, unsigned
int vector_length, gr_msg_queue_sptr queue, bool dump, std::string dump_filename, float pll_bw_hz, float dll_bw_hz, float early_late_space_chips) :
gr_block ("gps_l1_ca_dll_pll_tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
gr_make_io_signature(5, 5, sizeof(double))) {
int vector_length, gr_msg_queue_sptr queue, bool dump, std::string dump_filename, float pll_bw_hz, float dll_bw_hz, float early_late_space_chips) :
gr_block ("gps_l1_ca_dll_pll_tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
gr_make_io_signature(5, 5, sizeof(double)))
{
//gr_sync_decimator ("gps_l1_ca_dll_pll_tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
// gr_make_io_signature(3, 3, sizeof(float)),vector_length) {
// initialize internal vars
d_queue = queue;
d_dump = dump;
d_satellite = satellite;
d_if_freq = if_freq;
d_fs_in = fs_in;
d_vector_length = vector_length;
d_dump_filename =dump_filename;
//gr_sync_decimator ("gps_l1_ca_dll_pll_tracking_cc", gr_make_io_signature (1, 1, sizeof(gr_complex)),
// gr_make_io_signature(3, 3, sizeof(float)),vector_length) {
// initialize internal vars
d_queue = queue;
d_dump = dump;
d_satellite = satellite;
d_if_freq = if_freq;
d_fs_in = fs_in;
d_vector_length = vector_length;
d_dump_filename = dump_filename;
// Initialize tracking ==========================================
// Initialize tracking ==========================================
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_PLL_BW(pll_bw_hz);
d_code_loop_filter.set_DLL_BW(dll_bw_hz);
d_carrier_loop_filter.set_PLL_BW(pll_bw_hz);
//--- DLL variables --------------------------------------------------------
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
//--- DLL variables --------------------------------------------------------
d_early_late_spc_chips = early_late_space_chips; // Define early-late offset (in chips)
// Initialization of local code replica
// Initialization of local code replica
// Get space for a vector with the C/A code replica sampled 1x/chip
d_ca_code=new gr_complex[(int)GPS_L1_CA_CODE_LENGTH_CHIPS+2];
d_ca_code = new gr_complex[(int)GPS_L1_CA_CODE_LENGTH_CHIPS + 2];
// Get space for the resampled early / prompt / late local replicas
d_early_code= new gr_complex[d_vector_length*2];
d_prompt_code=new gr_complex[d_vector_length*2];
d_late_code=new gr_complex[d_vector_length*2];
d_early_code = new gr_complex[d_vector_length*2];
d_prompt_code = new gr_complex[d_vector_length*2];
d_late_code = new gr_complex[d_vector_length*2];
// space for carrier wipeoff and signal baseband vectors
d_carr_sign=new gr_complex[d_vector_length*2];
d_carr_sign = new gr_complex[d_vector_length*2];
//--- Perform initializations ------------------------------
// define initial code frequency basis of NCO
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ;
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ;
// define residual code phase (in chips)
d_rem_code_phase_samples = 0.0;
d_rem_code_phase_samples = 0.0;
// define residual carrier phase
d_rem_carr_phase_rad = 0.0;
d_rem_carr_phase_rad = 0.0;
// sample synchronization
d_sample_counter=0;
d_sample_counter_seconds=0;
d_acq_sample_stamp=0;
d_sample_counter = 0;
d_sample_counter_seconds = 0;
d_acq_sample_stamp = 0;
d_enable_tracking=false;
d_pull_in=false;
d_last_seg=0;
d_enable_tracking = false;
d_pull_in = false;
d_last_seg = 0;
d_current_prn_length_samples=(int)d_vector_length;
d_current_prn_length_samples = (int)d_vector_length;
// CN0 estimation and lock detector buffers
d_cn0_estimation_counter=0;
d_Prompt_buffer=new gr_complex[CN0_ESTIMATION_SAMPLES];
d_carrier_lock_test=1;
d_CN0_SNV_dB_Hz=0;
d_carrier_lock_fail_counter=0;
d_carrier_lock_threshold=5;
d_cn0_estimation_counter = 0;
d_Prompt_buffer = new gr_complex[CN0_ESTIMATION_SAMPLES];
d_carrier_lock_test = 1;
d_CN0_SNV_dB_Hz = 0;
d_carrier_lock_fail_counter = 0;
d_carrier_lock_threshold = 5;
}
void gps_l1_ca_dll_pll_tracking_cc::start_tracking(){
/*
* correct the code phase according to the delay between acq and trk
*/
unsigned long int acq_trk_diff_samples;
float acq_trk_diff_seconds;
acq_trk_diff_samples=d_sample_counter-d_acq_sample_stamp;//-d_vector_length;
std::cout<<"acq_trk_diff_samples="<<acq_trk_diff_samples<<"\r\n";
acq_trk_diff_seconds=(float)acq_trk_diff_samples/(float)d_fs_in;
//doppler effect
// Fd=(C/(C+Vr))*F
float radial_velocity;
radial_velocity=(GPS_L1_FREQ_HZ+d_acq_carrier_doppler_hz)/GPS_L1_FREQ_HZ;
// new chip and prn sequence periods based on acq Doppler
float T_chip_mod_seconds;
float T_prn_mod_seconds;
float T_prn_mod_samples;
d_code_freq_hz=radial_velocity*GPS_L1_CA_CODE_RATE_HZ;
T_chip_mod_seconds=1/d_code_freq_hz;
T_prn_mod_seconds=T_chip_mod_seconds*GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_mod_samples=T_prn_mod_seconds*(float)d_fs_in;
void gps_l1_ca_dll_pll_tracking_cc::start_tracking()
{
/*
* correct the code phase according to the delay between acq and trk
*/
unsigned long int acq_trk_diff_samples;
float acq_trk_diff_seconds;
acq_trk_diff_samples = d_sample_counter - d_acq_sample_stamp;//-d_vector_length;
std::cout << "acq_trk_diff_samples=" << acq_trk_diff_samples << std::endl;
acq_trk_diff_seconds = (float)acq_trk_diff_samples / (float)d_fs_in;
//doppler effect
// Fd=(C/(C+Vr))*F
float radial_velocity;
radial_velocity = (GPS_L1_FREQ_HZ + d_acq_carrier_doppler_hz)/GPS_L1_FREQ_HZ;
// new chip and prn sequence periods based on acq Doppler
float T_chip_mod_seconds;
float T_prn_mod_seconds;
float T_prn_mod_samples;
d_code_freq_hz = radial_velocity * GPS_L1_CA_CODE_RATE_HZ;
T_chip_mod_seconds = 1/d_code_freq_hz;
T_prn_mod_seconds = T_chip_mod_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_mod_samples = T_prn_mod_seconds * (float)d_fs_in;
#ifdef GNSS_SDR_USE_BOOST_ROUND
d_next_prn_length_samples=round(T_prn_mod_samples);
#else
d_next_prn_length_samples=std::round(T_prn_mod_samples);
#endif
#ifdef GNSS_SDR_USE_BOOST_ROUND
d_next_prn_length_samples = round(T_prn_mod_samples);
#else
d_next_prn_length_samples = std::round(T_prn_mod_samples);
#endif
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS/GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds*(float)d_fs_in;
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
float T_prn_diff_seconds;
T_prn_diff_seconds=T_prn_true_seconds-T_prn_mod_seconds;
T_prn_diff_seconds = T_prn_true_seconds - T_prn_mod_seconds;
float N_prn_diff;
N_prn_diff=acq_trk_diff_seconds/T_prn_true_seconds;
float corrected_acq_phase_samples,delay_correction_samples;
corrected_acq_phase_samples=fmod((d_acq_code_phase_samples+T_prn_diff_seconds*N_prn_diff*(float)d_fs_in),T_prn_true_samples);
if (corrected_acq_phase_samples<0)
{
corrected_acq_phase_samples=T_prn_mod_samples+corrected_acq_phase_samples;
}
delay_correction_samples=d_acq_code_phase_samples-corrected_acq_phase_samples;
N_prn_diff = acq_trk_diff_seconds / T_prn_true_seconds;
float corrected_acq_phase_samples, delay_correction_samples;
corrected_acq_phase_samples = fmod((d_acq_code_phase_samples + T_prn_diff_seconds * N_prn_diff * (float)d_fs_in), T_prn_true_samples);
if (corrected_acq_phase_samples < 0)
{
corrected_acq_phase_samples = T_prn_mod_samples + corrected_acq_phase_samples;
}
delay_correction_samples = d_acq_code_phase_samples - corrected_acq_phase_samples;
d_acq_code_phase_samples=corrected_acq_phase_samples;
d_acq_code_phase_samples = corrected_acq_phase_samples;
d_carrier_doppler_hz=d_acq_carrier_doppler_hz;
// DLL/PLL filter initialization
d_carrier_loop_filter.initialize(d_carrier_doppler_hz); //initialize the carrier filter
d_code_loop_filter.initialize(d_acq_code_phase_samples); //initialize the code filter
d_carrier_doppler_hz = d_acq_carrier_doppler_hz;
// DLL/PLL filter initialization
d_carrier_loop_filter.initialize(d_carrier_doppler_hz); //initialize the carrier filter
d_code_loop_filter.initialize(d_acq_code_phase_samples); //initialize the code filter
// generate local reference ALWAYS starting at chip 1 (1 sample per chip)
code_gen_conplex(&d_ca_code[1],d_satellite,0);
d_ca_code[0]=d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS];
d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS+1]=d_ca_code[1];
// generate local reference ALWAYS starting at chip 1 (1 sample per chip)
code_gen_conplex(&d_ca_code[1], d_satellite, 0);
d_ca_code[0] = d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS];
d_ca_code[(int)GPS_L1_CA_CODE_LENGTH_CHIPS + 1] = d_ca_code[1];
d_carrier_lock_fail_counter=0;
d_rem_code_phase_samples=0;
d_rem_carr_phase_rad=0;
d_rem_code_phase_samples=0;
d_next_rem_code_phase_samples=0;
d_acc_carrier_phase_rad=0;
d_carrier_lock_fail_counter = 0;
d_rem_code_phase_samples = 0;
d_rem_carr_phase_rad = 0;
d_rem_code_phase_samples = 0;
d_next_rem_code_phase_samples = 0;
d_acc_carrier_phase_rad = 0;
d_code_phase_samples = d_acq_code_phase_samples;
d_code_phase_samples = d_acq_code_phase_samples;
// DEBUG OUTPUT
std::cout<<"Tracking start on channel "<<d_channel<<" for satellite ID* "<< this->d_satellite<< std::endl;
DLOG(INFO) << "Start tracking for satellite "<<this->d_satellite<<" received ";
// DEBUG OUTPUT
std::cout << "Tracking start on channel " << d_channel << " for satellite ID* " << this->d_satellite << std::endl;
DLOG(INFO) << "Start tracking for satellite "<< this->d_satellite << " received" << std::endl;
// enable tracking
d_pull_in=true;
d_enable_tracking=true;
std::cout<<"PULL-IN Doppler [Hz]= "<<d_carrier_doppler_hz<<" Code Phase correction [samples]="<<delay_correction_samples<<" PULL-IN Code Phase [samples]= "<<d_acq_code_phase_samples<<"\r\n";
// enable tracking
d_pull_in = true;
d_enable_tracking = true;
std::cout << "PULL-IN Doppler [Hz]=" << d_carrier_doppler_hz << " Code Phase correction [samples]=" << delay_correction_samples << " PULL-IN Code Phase [samples]=" << d_acq_code_phase_samples << std::endl;
}
void gps_l1_ca_dll_pll_tracking_cc::update_local_code()
{
float tcode_chips;
float rem_code_phase_chips;
int associated_chip_index;
int code_length_chips=(int)GPS_L1_CA_CODE_LENGTH_CHIPS;
// unified loop for E, P, L code vectors
rem_code_phase_chips=d_rem_code_phase_samples*(d_code_freq_hz/d_fs_in);
tcode_chips=-rem_code_phase_chips;
for (int i=0;i<d_current_prn_length_samples;i++)
{
#ifdef GNSS_SDR_USE_BOOST_ROUND
associated_chip_index=1+round(fmod(tcode_chips-d_early_late_spc_chips,code_length_chips));
d_early_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1+round(fmod(tcode_chips, code_length_chips));
d_prompt_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1+round(fmod(tcode_chips+d_early_late_spc_chips, code_length_chips));
d_late_code[i] = d_ca_code[associated_chip_index];
tcode_chips=tcode_chips+d_code_phase_step_chips;
#else
associated_chip_index=1+std::round(fmod(tcode_chips-d_early_late_spc_chips,code_length_chips));
d_early_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1+std::round(fmod(tcode_chips, code_length_chips));
d_prompt_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1+std::round(fmod(tcode_chips+d_early_late_spc_chips, code_length_chips));
d_late_code[i] = d_ca_code[associated_chip_index];
tcode_chips=tcode_chips+d_code_phase_step_chips;
#endif
}
float tcode_chips;
float rem_code_phase_chips;
int associated_chip_index;
int code_length_chips = (int)GPS_L1_CA_CODE_LENGTH_CHIPS;
// unified loop for E, P, L code vectors
rem_code_phase_chips = d_rem_code_phase_samples * (d_code_freq_hz / d_fs_in);
tcode_chips = -rem_code_phase_chips;
for (int i=0; i<d_current_prn_length_samples; i++)
{
#ifdef GNSS_SDR_USE_BOOST_ROUND
associated_chip_index = 1 + round(fmod(tcode_chips - d_early_late_spc_chips, code_length_chips));
d_early_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1 + round(fmod(tcode_chips, code_length_chips));
d_prompt_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1 + round(fmod(tcode_chips+d_early_late_spc_chips, code_length_chips));
d_late_code[i] = d_ca_code[associated_chip_index];
tcode_chips = tcode_chips + d_code_phase_step_chips;
#else
associated_chip_index = 1 + std::round(fmod(tcode_chips - d_early_late_spc_chips, code_length_chips));
d_early_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1 + std::round(fmod(tcode_chips, code_length_chips));
d_prompt_code[i] = d_ca_code[associated_chip_index];
associated_chip_index = 1 + std::round(fmod(tcode_chips+d_early_late_spc_chips, code_length_chips));
d_late_code[i] = d_ca_code[associated_chip_index];
tcode_chips = tcode_chips + d_code_phase_step_chips;
#endif
}
}
void gps_l1_ca_dll_pll_tracking_cc::update_local_carrier()
{
float phase_rad, phase_step_rad;
float phase_rad, phase_step_rad;
phase_step_rad = (float)TWO_PI*d_carrier_doppler_hz/(float)d_fs_in;
phase_rad=d_rem_carr_phase_rad;
for(int i = 0; i < d_current_prn_length_samples; i++) {
d_carr_sign[i] = gr_complex(cos(phase_rad),sin(phase_rad));
phase_step_rad = (float)TWO_PI*d_carrier_doppler_hz / (float)d_fs_in;
phase_rad = d_rem_carr_phase_rad;
for(int i = 0; i < d_current_prn_length_samples; i++)
{
d_carr_sign[i] = gr_complex(cos(phase_rad), sin(phase_rad));
phase_rad += phase_step_rad;
}
d_rem_carr_phase_rad=fmod(phase_rad,TWO_PI);
d_acc_carrier_phase_rad=d_acc_carrier_phase_rad+d_rem_carr_phase_rad;
d_rem_carr_phase_rad = fmod(phase_rad, TWO_PI);
d_acc_carrier_phase_rad = d_acc_carrier_phase_rad + d_rem_carr_phase_rad;
}
gps_l1_ca_dll_pll_tracking_cc::~gps_l1_ca_dll_pll_tracking_cc() {
d_dump_file.close();
gps_l1_ca_dll_pll_tracking_cc::~gps_l1_ca_dll_pll_tracking_cc()
{
d_dump_file.close();
delete[] d_ca_code;
delete[] d_early_code;
delete[] d_prompt_code;
@@ -271,318 +287,357 @@ gps_l1_ca_dll_pll_tracking_cc::~gps_l1_ca_dll_pll_tracking_cc() {
delete[] d_Prompt_buffer;
}
/* Tracking signal processing
* Notice that this is a class derived from gr_sync_decimator, so each of the ninput_items has vector_length samples
*/
int gps_l1_ca_dll_pll_tracking_cc::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)
{
// if ((unsigned int)ninput_items[0]<(d_vector_length*2))
// {
// std::cout<<"End of signal detected\r\n";
// const int samples_available = ninput_items[0];
// consume_each(samples_available);
// return 0;
// }
// if ((unsigned int)ninput_items[0]<(d_vector_length*2))
// {
// std::cout<<"End of signal detected\r\n";
// const int samples_available = ninput_items[0];
// consume_each(samples_available);
// return 0;
// }
// process vars
float carr_error;
float carr_nco;
float code_error;
float code_nco;
d_Early=gr_complex(0,0);
d_Prompt=gr_complex(0,0);
d_Late=gr_complex(0,0);
// process vars
float carr_error;
float carr_nco;
float code_error;
float code_nco;
d_Early = gr_complex(0,0);
d_Prompt = gr_complex(0,0);
d_Late = gr_complex(0,0);
if (d_enable_tracking==true){
/*
* Receiver signal alignment
*/
if (d_pull_in==true)
{
int samples_offset;
if (d_enable_tracking==true){
/*
* Receiver signal alignment
*/
if (d_pull_in==true)
{
int samples_offset;
// 28/11/2011 ACQ to TRK transition BUG CORRECTION
float acq_trk_shif_correction_samples;
int acq_to_trk_delay_samples;
acq_to_trk_delay_samples=d_sample_counter-d_acq_sample_stamp;
acq_trk_shif_correction_samples=d_next_prn_length_samples-fmod((float)acq_to_trk_delay_samples,(float)d_next_prn_length_samples);
//std::cout<<"acq_trk_shif_correction="<<acq_trk_shif_correction_samples<<"\r\n";
#ifdef GNSS_SDR_USE_BOOST_ROUND
samples_offset=round(d_acq_code_phase_samples+acq_trk_shif_correction_samples);
#else
samples_offset=std::round(d_acq_code_phase_samples+acq_trk_shif_correction_samples);
#endif
// /todo: Check if the sample counter sent to the next block as a time reference should be incremented AFTER sended or BEFORE
d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset)/(double)d_fs_in);
d_sample_counter=d_sample_counter+samples_offset; //count for the processed samples
d_pull_in=false;
//std::cout<<" samples_offset="<<samples_offset<<"\r\n";
consume_each(samples_offset); //shift input to perform alignement with local replica
return 1;
}
// 28/11/2011 ACQ to TRK transition BUG CORRECTION
float acq_trk_shif_correction_samples;
int acq_to_trk_delay_samples;
acq_to_trk_delay_samples = d_sample_counter - d_acq_sample_stamp;
acq_trk_shif_correction_samples = d_next_prn_length_samples - fmod((float)acq_to_trk_delay_samples, (float)d_next_prn_length_samples);
//std::cout<<"acq_trk_shif_correction="<<acq_trk_shif_correction_samples<<"\r\n";
#ifdef GNSS_SDR_USE_BOOST_ROUND
samples_offset=round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
#else
samples_offset=std::round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
#endif
// /todo: Check if the sample counter sent to the next block as a time reference should be incremented AFTER sended or BEFORE
d_sample_counter_seconds = d_sample_counter_seconds + (((double)samples_offset) / (double)d_fs_in);
d_sample_counter =d_sample_counter + samples_offset; //count for the processed samples
d_pull_in = false;
//std::cout<<" samples_offset="<<samples_offset<<"\r\n";
consume_each(samples_offset); //shift input to perform alignement with local replica
return 1;
}
const gr_complex* in = (gr_complex*) input_items[0]; //PRN start block alignement
double **out = (double **) &output_items[0];
// check for samples consistency
for(int i=0;i<d_current_prn_length_samples;i++) {
if (std::isnan(in[i].real())==true or std::isnan(in[i].imag())==true)// or std::isinf(in[i].real())==true or std::isinf(in[i].imag())==true)
{
const int samples_available= ninput_items[0];
d_sample_counter=d_sample_counter+samples_available;
LOG_AT_LEVEL(WARNING) << "Detected NaN samples at sample number "<<d_sample_counter;
consume_each(samples_available);
return 0;
}
}
// Update the prn length based on code freq (variable) and
// sampling frequency (fixed)
// variable code PRN sample block size
d_current_prn_length_samples=d_next_prn_length_samples;
const gr_complex* in = (gr_complex*) input_items[0]; //PRN start block alignement
double **out = (double **) &output_items[0];
update_local_code();
update_local_carrier();
// check for samples consistency
for(int i=0; i<d_current_prn_length_samples; i++) {
if (std::isnan(in[i].real()) == true or std::isnan(in[i].imag()) == true)// or std::isinf(in[i].real())==true or std::isinf(in[i].imag())==true)
{
const int samples_available = ninput_items[0];
d_sample_counter = d_sample_counter + samples_available;
LOG_AT_LEVEL(WARNING) << "Detected NaN samples at sample number "<< d_sample_counter << std::endl;
consume_each(samples_available);
return 0;
}
}
// Update the prn length based on code freq (variable) and
// sampling frequency (fixed)
// variable code PRN sample block size
d_current_prn_length_samples = d_next_prn_length_samples;
gr_complex bb_signal_sample(0,0);
update_local_code();
update_local_carrier();
// perform Early, Prompt and Late correlation
/*!
* \todo Use SIMD-enabled correlators
*/
for(int i=0;i<d_current_prn_length_samples;i++) {
//Perform the carrier wipe-off
bb_signal_sample = in[i] * d_carr_sign[i];
// Now get early, late, and prompt values for each
d_Early += bb_signal_sample*d_early_code[i];
d_Prompt += bb_signal_sample*d_prompt_code[i];
d_Late += bb_signal_sample*d_late_code[i];
}
// Compute PLL error and update carrier NCO -
carr_error=pll_cloop_two_quadrant_atan(d_Prompt)/ (float)TWO_PI;
// Implement carrier loop filter and generate NCO command
carr_nco=d_carrier_loop_filter.get_carrier_nco(carr_error);
// Modify carrier freq based on NCO command
d_carrier_doppler_hz = d_acq_carrier_doppler_hz + carr_nco;
gr_complex bb_signal_sample(0,0);
// Compute DLL error and update code NCO
code_error=dll_nc_e_minus_l_normalized(d_Early,d_Late);
// Implement code loop filter and generate NCO command
code_nco=d_code_loop_filter.get_code_nco(code_error);
// Modify code freq based on NCO command
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ - code_nco;
// perform Early, Prompt and Late correlation
/*!
* \todo Use SIMD-enabled correlators
*/
for(int i=0; i<d_current_prn_length_samples; i++) {
//Perform the carrier wipe-off
bb_signal_sample = in[i] * d_carr_sign[i];
// Now get early, late, and prompt values for each
d_Early += bb_signal_sample * d_early_code[i];
d_Prompt += bb_signal_sample * d_prompt_code[i];
d_Late += bb_signal_sample * d_late_code[i];
}
// Update the phasestep based on code freq (variable) and
// sampling frequency (fixed)
d_code_phase_step_chips = d_code_freq_hz / (float)d_fs_in; //[chips]
// variable code PRN sample block size
float T_chip_seconds;
float T_prn_seconds;
float T_prn_samples;
float K_blk_samples;
T_chip_seconds=1/d_code_freq_hz;
T_prn_seconds=T_chip_seconds*GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples=T_prn_seconds*d_fs_in;
d_rem_code_phase_samples=d_next_rem_code_phase_samples;
K_blk_samples=T_prn_samples+d_rem_code_phase_samples;
// Compute PLL error and update carrier NCO -
carr_error = pll_cloop_two_quadrant_atan(d_Prompt) / (float)TWO_PI;
// Implement carrier loop filter and generate NCO command
carr_nco = d_carrier_loop_filter.get_carrier_nco(carr_error);
// Modify carrier freq based on NCO command
d_carrier_doppler_hz = d_acq_carrier_doppler_hz + carr_nco;
// Update the current PRN delay (code phase in samples)
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS/GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds*(float)d_fs_in;
d_code_phase_samples=d_code_phase_samples+T_prn_samples-T_prn_true_samples;
if (d_code_phase_samples<0)
{
d_code_phase_samples=T_prn_true_samples+d_code_phase_samples;
}
// Compute DLL error and update code NCO
code_error = dll_nc_e_minus_l_normalized(d_Early, d_Late);
// Implement code loop filter and generate NCO command
code_nco = d_code_loop_filter.get_code_nco(code_error);
// Modify code freq based on NCO command
d_code_freq_hz = GPS_L1_CA_CODE_RATE_HZ - code_nco;
d_code_phase_samples=fmod(d_code_phase_samples,T_prn_true_samples);
// Update the phasestep based on code freq (variable) and
// sampling frequency (fixed)
d_code_phase_step_chips = d_code_freq_hz / (float)d_fs_in; //[chips]
// variable code PRN sample block size
float T_chip_seconds;
float T_prn_seconds;
float T_prn_samples;
float K_blk_samples;
T_chip_seconds = 1 / d_code_freq_hz;
T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples = T_prn_seconds * d_fs_in;
d_rem_code_phase_samples = d_next_rem_code_phase_samples;
K_blk_samples = T_prn_samples + d_rem_code_phase_samples;
// Update the current PRN delay (code phase in samples)
float T_prn_true_seconds = GPS_L1_CA_CODE_LENGTH_CHIPS / GPS_L1_CA_CODE_RATE_HZ;
float T_prn_true_samples = T_prn_true_seconds * (float)d_fs_in;
d_code_phase_samples = d_code_phase_samples + T_prn_samples - T_prn_true_samples;
if (d_code_phase_samples < 0)
{
d_code_phase_samples = T_prn_true_samples + d_code_phase_samples;
}
d_code_phase_samples = fmod(d_code_phase_samples, T_prn_true_samples);
#ifdef GNSS_SDR_USE_BOOST_ROUND
d_next_prn_length_samples=round(K_blk_samples); //round to a discrete samples
d_next_prn_length_samples = round(K_blk_samples); //round to a discrete samples
#else
d_next_prn_length_samples=std::round(K_blk_samples); //round to a discrete samples
d_next_prn_length_samples = std::round(K_blk_samples); //round to a discrete samples
#endif
d_next_rem_code_phase_samples=K_blk_samples-d_next_prn_length_samples; //rounding error
d_next_rem_code_phase_samples = K_blk_samples - d_next_prn_length_samples; //rounding error
/*!
* \todo Improve the lock detection algorithm!
*/
// ####### CN0 ESTIMATION AND LOCK DETECTORS ######
if (d_cn0_estimation_counter<CN0_ESTIMATION_SAMPLES)
{
// fill buffer with prompt correlator output values
d_Prompt_buffer[d_cn0_estimation_counter]=d_Prompt;
d_cn0_estimation_counter++;
}else{
d_cn0_estimation_counter=0;
d_CN0_SNV_dB_Hz=gps_l1_ca_CN0_SNV(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES,d_fs_in);
d_carrier_lock_test=carrier_lock_detector(d_Prompt_buffer,CN0_ESTIMATION_SAMPLES);
// ###### TRACKING UNLOCK NOTIFICATION #####
int tracking_message;
if (d_carrier_lock_test<d_carrier_lock_threshold or d_carrier_lock_test>MINIMUM_VALID_CN0)
{
d_carrier_lock_fail_counter++;
}else{
if (d_carrier_lock_fail_counter>0) d_carrier_lock_fail_counter--;
}
if (d_carrier_lock_fail_counter>MAXIMUM_LOCK_FAIL_COUNTER)
{
std::cout<<"Channel "<<d_channel << " loss of lock!\r\n";
tracking_message=3; //loss of lock
d_channel_internal_queue->push(tracking_message);
d_carrier_lock_fail_counter=0;
d_enable_tracking=false; // TODO: check if disabling tracking is consistent with the channel state machine
/*!
* \todo Improve the lock detection algorithm!
*/
// ####### CN0 ESTIMATION AND LOCK DETECTORS ######
if (d_cn0_estimation_counter < CN0_ESTIMATION_SAMPLES)
{
// fill buffer with prompt correlator output values
d_Prompt_buffer[d_cn0_estimation_counter] = d_Prompt;
d_cn0_estimation_counter++;
}
else
{
d_cn0_estimation_counter = 0;
d_CN0_SNV_dB_Hz = gps_l1_ca_CN0_SNV(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES, d_fs_in);
d_carrier_lock_test = carrier_lock_detector(d_Prompt_buffer, CN0_ESTIMATION_SAMPLES);
// ###### TRACKING UNLOCK NOTIFICATION #####
int tracking_message;
if (d_carrier_lock_test < d_carrier_lock_threshold or d_carrier_lock_test > MINIMUM_VALID_CN0)
{
d_carrier_lock_fail_counter++;
}
else
{
if (d_carrier_lock_fail_counter > 0) d_carrier_lock_fail_counter--;
}
if (d_carrier_lock_fail_counter > MAXIMUM_LOCK_FAIL_COUNTER)
{
std::cout << "Channel " << d_channel << " loss of lock!" << std::endl ;
tracking_message = 3; //loss of lock
d_channel_internal_queue->push(tracking_message);
d_carrier_lock_fail_counter = 0;
d_enable_tracking = false; // TODO: check if disabling tracking is consistent with the channel state machine
}
//std::cout<<"d_carrier_lock_fail_counter"<<d_carrier_lock_fail_counter<<"\r\n";
}
}
//std::cout<<"d_carrier_lock_fail_counter"<<d_carrier_lock_fail_counter<<"\r\n";
}
/*!
* \todo Output the CN0
*/
// ########### Output the tracking data to navigation and PVT ##########
// Output channel 0: Prompt correlator output Q
*out[0]=(double)d_Prompt.real();
// Output channel 1: Prompt correlator output I
*out[1]=(double)d_Prompt.imag();
// Output channel 2: PRN absolute delay [s]
*out[2]=d_sample_counter_seconds;
// Output channel 3: d_acc_carrier_phase_rad [rad]
*out[3]=(double)d_acc_carrier_phase_rad;
// Output channel 4: PRN code phase [s]
*out[4]=(double)d_code_phase_samples*(1/(float)d_fs_in);
/*!
* \todo Output the CN0
*/
// ########### Output the tracking data to navigation and PVT ##########
// Output channel 0: Prompt correlator output Q
*out[0] = (double)d_Prompt.real();
// Output channel 1: Prompt correlator output I
*out[1] = (double)d_Prompt.imag();
// Output channel 2: PRN absolute delay [s]
*out[2] = d_sample_counter_seconds;
// Output channel 3: d_acc_carrier_phase_rad [rad]
*out[3] = (double)d_acc_carrier_phase_rad;
// Output channel 4: PRN code phase [s]
*out[4] = (double)d_code_phase_samples * (1 / (float)d_fs_in);
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
*/
// debug: Second counter in channel 0
if (d_channel==0)
{
if (floor(d_sample_counter/d_fs_in)!=d_last_seg)
{
d_last_seg=floor(d_sample_counter/d_fs_in);
std::cout<<"Current input signal time="<<d_last_seg<<" [s]"<<std::endl;
std::cout<<"Tracking CH "<<d_channel<<" CN0="<<d_CN0_SNV_dB_Hz<<" [dB-Hz]"<<std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
}else
{
if (floor(d_sample_counter/d_fs_in)!=d_last_seg)
{
d_last_seg=floor(d_sample_counter/d_fs_in);
std::cout<<"Tracking CH "<<d_channel<<" CN0="<<d_CN0_SNV_dB_Hz<<" [dB-Hz]"<<std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
}
}
}else{
double **out = (double **) &output_items[0]; //block output streams pointer
*out[0]=0;
*out[1]=0;
*out[2]=0;
*out[3]=0;
*out[4]=0;
}
// ########## DEBUG OUTPUT
/*!
* \todo The stop timer has to be moved to the signal source!
*/
// debug: Second counter in channel 0
if (d_channel == 0)
{
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
std::cout << "Current input signal time=" << d_last_seg << " [s]" << std::endl;
std::cout << "Tracking CH " << d_channel << " CN0=" << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
//if (d_last_seg==5) d_carrier_lock_fail_counter=500; //DEBUG: force unlock!
}
}
else
{
if (floor(d_sample_counter / d_fs_in) != d_last_seg)
{
d_last_seg = floor(d_sample_counter / d_fs_in);
std::cout << "Tracking CH "<< d_channel << " CN0=" << d_CN0_SNV_dB_Hz << " [dB-Hz]" << std::endl;
//std::cout<<"TRK CH "<<d_channel<<" Carrier_lock_test="<<d_carrier_lock_test<< std::endl;
}
}
}
else
{
double **out = (double **) &output_items[0]; //block output streams pointer
*out[0] = 0;
*out[1] = 0;
*out[2] = 0;
*out[3] = 0;
*out[4] = 0;
}
if(d_dump) {
// MULTIPLEXED FILE RECORDING - Record results to file
float prompt_I;
float prompt_Q;
float tmp_E,tmp_P,tmp_L;
float tmp_float;
prompt_I=d_Prompt.imag();
prompt_Q=d_Prompt.real();
tmp_E=std::abs<float>(d_Early);
tmp_P=std::abs<float>(d_Prompt);
tmp_L=std::abs<float>(d_Late);
try {
// EPR
d_dump_file.write((char*)&tmp_E, sizeof(float));
d_dump_file.write((char*)&tmp_P, sizeof(float));
d_dump_file.write((char*)&tmp_L, sizeof(float));
// PROMPT I and Q (to analyze navigation symbols)
d_dump_file.write((char*)&prompt_I, sizeof(float));
d_dump_file.write((char*)&prompt_Q, sizeof(float));
// PRN start sample stamp
//tmp_float=(float)d_sample_counter;
d_dump_file.write((char*)&d_sample_counter, sizeof(unsigned long int));
// accumulated carrier phase
d_dump_file.write((char*)&d_acc_carrier_phase_rad, sizeof(float));
if(d_dump) {
// MULTIPLEXED FILE RECORDING - Record results to file
float prompt_I;
float prompt_Q;
float tmp_E, tmp_P, tmp_L;
float tmp_float;
prompt_I = d_Prompt.imag();
prompt_Q = d_Prompt.real();
tmp_E = std::abs<float>(d_Early);
tmp_P = std::abs<float>(d_Prompt);
tmp_L = std::abs<float>(d_Late);
try
{
// EPR
d_dump_file.write((char*)&tmp_E, sizeof(float));
d_dump_file.write((char*)&tmp_P, sizeof(float));
d_dump_file.write((char*)&tmp_L, sizeof(float));
// PROMPT I and Q (to analyze navigation symbols)
d_dump_file.write((char*)&prompt_I, sizeof(float));
d_dump_file.write((char*)&prompt_Q, sizeof(float));
// PRN start sample stamp
//tmp_float=(float)d_sample_counter;
d_dump_file.write((char*)&d_sample_counter, sizeof(unsigned long int));
// accumulated carrier phase
d_dump_file.write((char*)&d_acc_carrier_phase_rad, sizeof(float));
// carrier and code frequency
d_dump_file.write((char*)&d_carrier_doppler_hz, sizeof(float));
d_dump_file.write((char*)&d_code_freq_hz, sizeof(float));
// carrier and code frequency
d_dump_file.write((char*)&d_carrier_doppler_hz, sizeof(float));
d_dump_file.write((char*)&d_code_freq_hz, sizeof(float));
//PLL commands
d_dump_file.write((char*)&carr_error, sizeof(float));
d_dump_file.write((char*)&carr_nco, sizeof(float));
//PLL commands
d_dump_file.write((char*)&carr_error, sizeof(float));
d_dump_file.write((char*)&carr_nco, sizeof(float));
//DLL commands
d_dump_file.write((char*)&code_error, sizeof(float));
d_dump_file.write((char*)&code_nco, sizeof(float));
//DLL commands
d_dump_file.write((char*)&code_error, sizeof(float));
d_dump_file.write((char*)&code_nco, sizeof(float));
// CN0 and carrier lock test
d_dump_file.write((char*)&d_CN0_SNV_dB_Hz, sizeof(float));
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
// CN0 and carrier lock test
d_dump_file.write((char*)&d_CN0_SNV_dB_Hz, sizeof(float));
d_dump_file.write((char*)&d_carrier_lock_test, sizeof(float));
// AUX vars (for debug purposes)
tmp_float=0;
d_dump_file.write((char*)&tmp_float, sizeof(float));
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
}
catch (std::ifstream::failure e) {
std::cout << "Exception writing trk dump file "<<e.what()<<"\r\n";
}
}
// AUX vars (for debug purposes)
tmp_float=0;
d_dump_file.write((char*)&tmp_float, sizeof(float));
d_dump_file.write((char*)&d_sample_counter_seconds, sizeof(double));
}
catch (std::ifstream::failure e)
{
std::cout << "Exception writing trk dump file " << e.what() << std::endl;
}
}
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
d_sample_counter_seconds = d_sample_counter_seconds + (((double)d_current_prn_length_samples)/(double)d_fs_in);
d_sample_counter+=d_current_prn_length_samples; //count for the processed samples
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
consume_each(d_current_prn_length_samples); // this is necesary in gr_block derivates
d_sample_counter_seconds = d_sample_counter_seconds + ( ((double)d_current_prn_length_samples) / (double)d_fs_in );
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
return 1; //output tracking result ALWAYS even in the case of d_enable_tracking==false
}
void gps_l1_ca_dll_pll_tracking_cc::set_acq_code_phase(float code_phase) {
void gps_l1_ca_dll_pll_tracking_cc::set_acq_code_phase(float code_phase)
{
d_acq_code_phase_samples = code_phase;
LOG_AT_LEVEL(INFO) << "Tracking code phase set to " << d_acq_code_phase_samples;
}
void gps_l1_ca_dll_pll_tracking_cc::set_acq_doppler(float doppler) {
void gps_l1_ca_dll_pll_tracking_cc::set_acq_doppler(float doppler)
{
d_acq_carrier_doppler_hz = doppler;
LOG_AT_LEVEL(INFO) << "Tracking carrier doppler set to " << d_acq_carrier_doppler_hz;
}
void gps_l1_ca_dll_pll_tracking_cc::set_satellite(unsigned int satellite) {
void gps_l1_ca_dll_pll_tracking_cc::set_satellite(unsigned int satellite)
{
d_satellite = satellite;
LOG_AT_LEVEL(INFO) << "Tracking Satellite set to " << d_satellite;
}
void gps_l1_ca_dll_pll_tracking_cc::set_channel(unsigned int channel) {
d_channel = channel;
LOG_AT_LEVEL(INFO) << "Tracking Channel set to " << d_channel;
// ############# ENABLE DATA FILE LOG #################
if (d_dump==true)
{
if (d_dump_file.is_open()==false)
{
try {
d_dump_filename.append(boost::lexical_cast<std::string>(d_channel));
d_dump_filename.append(".dat");
d_dump_file.exceptions ( std::ifstream::failbit | std::ifstream::badbit );
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
std::cout<<"Tracking dump enabled on channel "<<d_channel<<" Log file: "<<d_dump_filename.c_str()<<std::endl;
}
catch (std::ifstream::failure e) {
std::cout << "channel "<<d_channel <<" Exception opening trk dump file "<<e.what()<<"\r\n";
}
}
}
void gps_l1_ca_dll_pll_tracking_cc::set_channel(unsigned int channel)
{
d_channel = channel;
LOG_AT_LEVEL(INFO) << "Tracking Channel set to " << d_channel;
// ############# ENABLE DATA FILE LOG #################
if (d_dump==true)
{
if (d_dump_file.is_open()==false)
{
try
{
d_dump_filename.append(boost::lexical_cast<std::string>(d_channel));
d_dump_filename.append(".dat");
d_dump_file.exceptions (std::ifstream::failbit | std::ifstream::badbit);
d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
std::cout << "Tracking dump enabled on channel " << d_channel << " Log file: " << d_dump_filename.c_str() << std::endl;
}
catch (std::ifstream::failure e)
{
std::cout << "channel "<< d_channel << " Exception opening trk dump file " << e.what() << std::endl;
}
}
}
}
void gps_l1_ca_dll_pll_tracking_cc::set_acq_sample_stamp(unsigned long int sample_stamp)
{
d_acq_sample_stamp = sample_stamp;
}
void gps_l1_ca_dll_pll_tracking_cc::set_channel_queue(concurrent_queue<int> *channel_internal_queue)
{
d_channel_internal_queue = channel_internal_queue;

51
src/algorithms/tracking/libs/CN_estimators.cc
View File

@@ -70,22 +70,22 @@ float gps_l1_ca_CN0_SNV(gr_complex* Prompt_buffer, int length, long fs_in)
//SNR_SNV(count)=Psig/(Ptot-Psig);
//CN0_SNV_dB=10*log10(SNR_SNV)+10*log10(BW)-10*log10(PRN_length);
float SNR, SNR_dB_Hz;
float tmp_abs_I,tmp_abs_Q;
float Psig,Ptot;
float tmp_abs_I, tmp_abs_Q;
float Psig, Ptot;
//float M2,M4;
Psig=0;
Ptot=0;
for (int i=0;i<length;i++)
Psig = 0;
Ptot = 0;
for (int i=0; i<length; i++)
{
tmp_abs_I=std::abs(Prompt_buffer[i].imag());
tmp_abs_Q=std::abs(Prompt_buffer[i].real());
Psig+=tmp_abs_I;
Ptot+=Prompt_buffer[i].imag()*Prompt_buffer[i].imag()+Prompt_buffer[i].real()*Prompt_buffer[i].real();
tmp_abs_I = std::abs(Prompt_buffer[i].imag());
tmp_abs_Q = std::abs(Prompt_buffer[i].real());
Psig += tmp_abs_I;
Ptot += Prompt_buffer[i].imag()*Prompt_buffer[i].imag() + Prompt_buffer[i].real()*Prompt_buffer[i].real();
}
Psig=Psig/(float)length;
Psig=Psig*Psig;
SNR=Psig/(Ptot/(float)length-Psig);
SNR_dB_Hz=10*log10(SNR)+10*log10(fs_in/2)-10*log10(GPS_L1_CA_CODE_LENGTH_CHIPS);
Psig = Psig / (float)length;
Psig = Psig*Psig;
SNR = Psig / (Ptot / (float)length - Psig);
SNR_dB_Hz = 10*log10(SNR) + 10*log10(fs_in/2) - 10*log10(GPS_L1_CA_CODE_LENGTH_CHIPS);
return SNR_dB_Hz;
}
@@ -109,26 +109,25 @@ float carrier_lock_detector(gr_complex* Prompt_buffer, int length)
//NBD=sum(abs(imag(x((n-N+1):n))))^2 + sum(abs(real(x((n-N+1):n))))^2;
//NBP=sum(imag(x((n-N+1):n)).^2) - sum(real(x((n-N+1):n)).^2);
//LOCK(count)=NBD/NBP;
float tmp_abs_I,tmp_abs_Q;
float tmp_sum_abs_I,tmp_sum_abs_Q;
float tmp_sum_sqr_I,tmp_sum_sqr_Q;
float tmp_abs_I, tmp_abs_Q;
float tmp_sum_abs_I, tmp_sum_abs_Q;
float tmp_sum_sqr_I, tmp_sum_sqr_Q;
tmp_sum_abs_I=0;
tmp_sum_abs_Q=0;
tmp_sum_sqr_I=0;
tmp_sum_sqr_Q=0;
float NBD,NBP;
for (int i=0;i<length;i++)
for (int i=0; i<length; i++)
{
tmp_abs_I=std::abs(Prompt_buffer[i].imag());
tmp_abs_Q=std::abs(Prompt_buffer[i].real());
tmp_sum_abs_I+=tmp_abs_I;
tmp_sum_abs_Q+=tmp_abs_Q;
tmp_sum_sqr_I+=(Prompt_buffer[i].imag()*Prompt_buffer[i].imag());
tmp_sum_sqr_Q+=(Prompt_buffer[i].real()*Prompt_buffer[i].real());
tmp_abs_I = std::abs(Prompt_buffer[i].imag());
tmp_abs_Q = std::abs(Prompt_buffer[i].real());
tmp_sum_abs_I += tmp_abs_I;
tmp_sum_abs_Q += tmp_abs_Q;
tmp_sum_sqr_I += (Prompt_buffer[i].imag()*Prompt_buffer[i].imag());
tmp_sum_sqr_Q += (Prompt_buffer[i].real()*Prompt_buffer[i].real());
}
NBD=tmp_sum_abs_I*tmp_sum_abs_I+tmp_sum_abs_Q*tmp_sum_abs_Q;
NBP=tmp_sum_sqr_I-tmp_sum_sqr_Q;
NBD = tmp_sum_abs_I*tmp_sum_abs_I + tmp_sum_abs_Q*tmp_sum_abs_Q;
NBP = tmp_sum_sqr_I - tmp_sum_sqr_Q;
return NBD/NBP;
}

22
src/algorithms/tracking/libs/tracking_2nd_DLL_filter.cc
View File

@@ -38,7 +38,8 @@
#include "tracking_2nd_DLL_filter.h"
void tracking_2nd_DLL_filter::calculate_lopp_coef(float* tau1,float* tau2, float lbw, float zeta, float k){
void tracking_2nd_DLL_filter::calculate_lopp_coef(float* tau1,float* tau2, float lbw, float zeta, float k)
{
// Solve natural frequency
float Wn;
Wn = lbw*8*zeta / (4*zeta*zeta + 1);
@@ -47,20 +48,26 @@ void tracking_2nd_DLL_filter::calculate_lopp_coef(float* tau1,float* tau2, float
*tau2 = (2.0 * zeta) / Wn;
}
void tracking_2nd_DLL_filter::set_DLL_BW(float dll_bw_hz)
{
//Calculate filter coefficient values
d_dllnoisebandwidth=dll_bw_hz;
calculate_lopp_coef(&d_tau1_code, &d_tau2_code, d_dllnoisebandwidth, d_dlldampingratio,1.0);// Calculate filter coefficient values
d_dllnoisebandwidth =dll_bw_hz;
calculate_lopp_coef(&d_tau1_code, &d_tau2_code, d_dllnoisebandwidth, d_dlldampingratio, 1.0);// Calculate filter coefficient values
}
void tracking_2nd_DLL_filter::initialize(float d_acq_code_phase_samples)
{
// code tracking loop parameters
d_old_code_nco = 0.0;
d_old_code_error = 0.0;
}
float tracking_2nd_DLL_filter::get_code_nco(float DLL_discriminator)
{
float code_nco;
@@ -70,13 +77,14 @@ float tracking_2nd_DLL_filter::get_code_nco(float DLL_discriminator)
return code_nco;
}
tracking_2nd_DLL_filter::tracking_2nd_DLL_filter ()
{
d_pdi_code = 0.001;// Summation interval for code
d_dlldampingratio=0.7;
d_dlldampingratio = 0.7;
}
tracking_2nd_DLL_filter::~tracking_2nd_DLL_filter ()
{
{}
}

24
src/algorithms/tracking/libs/tracking_discriminators.cc
View File

@@ -47,9 +47,9 @@
float fll_four_quadrant_atan(gr_complex prompt_s1, gr_complex prompt_s2,float t1, float t2)
{
float cross,dot;
dot=prompt_s1.imag()*prompt_s2.imag()+prompt_s1.real()*prompt_s2.real();
cross=prompt_s1.imag()*prompt_s2.real()-prompt_s2.imag()*prompt_s1.real();
return atan2(cross,dot)/(t2-t1);
dot = prompt_s1.imag()*prompt_s2.imag() + prompt_s1.real()*prompt_s2.real();
cross = prompt_s1.imag()*prompt_s2.real() - prompt_s2.imag()*prompt_s1.real();
return atan2(cross, dot) / (t2-t1);
}
@@ -62,7 +62,7 @@ float fll_four_quadrant_atan(gr_complex prompt_s1, gr_complex prompt_s2,float t1
*/
float pll_four_quadrant_atan(gr_complex prompt_s1)
{
return atan2(prompt_s1.real(),prompt_s1.imag());
return atan2(prompt_s1.real(), prompt_s1.imag());
}
@@ -75,11 +75,13 @@ float pll_four_quadrant_atan(gr_complex prompt_s1)
*/
float pll_cloop_two_quadrant_atan(gr_complex prompt_s1)
{
if (prompt_s1.imag()!=0.0)
if (prompt_s1.imag() != 0.0)
{
return atan(prompt_s1.real()/prompt_s1.imag());
}else{
return 0;
return atan(prompt_s1.real() / prompt_s1.imag());
}
else
{
return 0;
}
}
@@ -95,7 +97,7 @@ float pll_cloop_two_quadrant_atan(gr_complex prompt_s1)
float dll_nc_e_minus_l_normalized(gr_complex early_s1, gr_complex late_s1)
{
float P_early, P_late;
P_early=std::abs(early_s1);
P_late=std::abs(late_s1);
return (P_early-P_late)/((P_early+P_late));
P_early = std::abs(early_s1);
P_late = std::abs(late_s1);
return (P_early - P_late) / ((P_early + P_late));
}