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Code Issues Releases Wiki Activity

Code cleaning

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This commit is contained in:
Carles Fernandez
2017-01-28 15:31:04 +01:00
parent d2c7bb62a1
commit 4438ffe916
10 changed files with 266 additions and 275 deletions
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62
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.cc
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@@ -193,10 +193,10 @@ void Gps_L1_Ca_Dll_Pll_Tracking_cc::start_tracking()
long int acq_trk_diff_samples;
double acq_trk_diff_seconds;
acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp);//-d_vector_length;
acq_trk_diff_samples = static_cast<long int>(d_sample_counter) - static_cast<long int>(d_acq_sample_stamp); //-d_vector_length;
DLOG(INFO) << "Number of samples between Acquisition and Tracking =" << acq_trk_diff_samples;
acq_trk_diff_seconds = static_cast<float>(acq_trk_diff_samples) / static_cast<float>(d_fs_in);
//doppler effect
// Doppler effect
// Fd=(C/(C+Vr))*F
double 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
@@ -309,14 +309,14 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
acq_trk_shif_correction_samples = d_current_prn_length_samples - fmod(static_cast<float>(acq_to_trk_delay_samples), static_cast<float>(d_current_prn_length_samples));
samples_offset = round(d_acq_code_phase_samples + acq_trk_shif_correction_samples);
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
d_sample_counter = d_sample_counter + samples_offset; //count for the processed samples
d_sample_counter = d_sample_counter + samples_offset; // count for the processed samples
d_pull_in = false;
//take into account the carrier cycles accumulated in the pull in signal alignement
// take into account the carrier cycles accumulated in the pull in signal alignment
d_acc_carrier_phase_rad -= d_carrier_phase_step_rad * samples_offset;
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
*out[0] = current_synchro_data;
consume_each(samples_offset); //shift input to perform alignment with local replica
consume_each(samples_offset); // shift input to perform alignment with local replica
return 1;
}
@@ -332,7 +332,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
// ################## PLL ##########################################################
// PLL discriminator
// Update PLL discriminator [rads/Ti -> Secs/Ti]
carr_error_hz = pll_cloop_two_quadrant_atan(d_correlator_outs[1]) / GPS_TWO_PI; //prompt output
carr_error_hz = pll_cloop_two_quadrant_atan(d_correlator_outs[1]) / GPS_TWO_PI; // prompt output
// Carrier discriminator filter
carr_error_filt_hz = d_carrier_loop_filter.get_carrier_nco(carr_error_hz);
// New carrier Doppler frequency estimation
@@ -342,40 +342,34 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
// ################## DLL ##########################################################
// DLL discriminator
code_error_chips = dll_nc_e_minus_l_normalized(d_correlator_outs[0], d_correlator_outs[2]); //[chips/Ti] //early and late
code_error_chips = dll_nc_e_minus_l_normalized(d_correlator_outs[0], d_correlator_outs[2]); // [chips/Ti] //early and late
// Code discriminator filter
code_error_filt_chips = d_code_loop_filter.get_code_nco(code_error_chips); //[chips/second]
//Code phase accumulator
double code_error_filt_secs;
code_error_filt_secs = (GPS_L1_CA_CODE_PERIOD * code_error_filt_chips) / GPS_L1_CA_CODE_RATE_HZ; //[seconds]
code_error_filt_chips = d_code_loop_filter.get_code_nco(code_error_chips); // [chips/second]
double code_error_filt_secs = (GPS_L1_CA_CODE_PERIOD * code_error_filt_chips) / GPS_L1_CA_CODE_RATE_HZ; // [seconds]
// ################## CARRIER AND CODE NCO BUFFER ALIGNEMENT #######################
// keep alignment parameters for the next input buffer
double T_chip_seconds;
double T_prn_seconds;
double T_prn_samples;
double K_blk_samples;
// Compute the next buffer length based in the new period of the PRN sequence and the code phase error estimation
T_chip_seconds = 1 / static_cast<double>(d_code_freq_chips);
T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
K_blk_samples = T_prn_samples + d_rem_code_phase_samples + code_error_filt_secs * static_cast<double>(d_fs_in);
d_current_prn_length_samples = round(K_blk_samples); //round to a discrete samples
double T_chip_seconds = 1.0 / static_cast<double>(d_code_freq_chips);
double T_prn_seconds = T_chip_seconds * GPS_L1_CA_CODE_LENGTH_CHIPS;
double T_prn_samples = T_prn_seconds * static_cast<double>(d_fs_in);
double K_blk_samples = T_prn_samples + d_rem_code_phase_samples + code_error_filt_secs * static_cast<double>(d_fs_in);
d_current_prn_length_samples = round(K_blk_samples); // round to a discrete number of samples
//################### PLL COMMANDS #################################################
//carrier phase step (NCO phase increment per sample) [rads/sample]
// carrier phase step (NCO phase increment per sample) [rads/sample]
d_carrier_phase_step_rad = GPS_TWO_PI * d_carrier_doppler_hz / static_cast<double>(d_fs_in);
//remanent carrier phase to prevent overflow in the code NCO
// remnant carrier phase to prevent overflow in the code NCO
d_rem_carr_phase_rad = d_rem_carr_phase_rad + d_carrier_phase_step_rad * d_current_prn_length_samples;
d_rem_carr_phase_rad = fmod(d_rem_carr_phase_rad, GPS_TWO_PI);
//carrier phase accumulator for (K) doppler estimation
// carrier phase accumulator
d_acc_carrier_phase_rad -= d_carrier_phase_step_rad * d_current_prn_length_samples;
//################### DLL COMMANDS #################################################
//code phase step (Code resampler phase increment per sample) [chips/sample]
// code phase step (Code resampler phase increment per sample) [chips/sample]
d_code_phase_step_chips = d_code_freq_chips / static_cast<double>(d_fs_in);
//remnant code phase [chips]
d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; //rounding error < 1 sample
// remnant code phase [chips]
d_rem_code_phase_samples = K_blk_samples - d_current_prn_length_samples; // rounding error < 1 sample
d_rem_code_phase_chips = d_code_freq_chips * (d_rem_code_phase_samples / static_cast<double>(d_fs_in));
// ####### CN0 ESTIMATION AND LOCK DETECTORS ######
@@ -405,7 +399,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
{
std::cout << "Loss of lock in channel " << d_channel << "!" << std::endl;
LOG(INFO) << "Loss of lock in channel " << d_channel << "!";
this->message_port_pub(pmt::mp("events"), pmt::from_long(3));//3 -> loss of lock
this->message_port_pub(pmt::mp("events"), pmt::from_long(3)); // 3 -> loss of lock
d_carrier_lock_fail_counter = 0;
d_enable_tracking = false; // TODO: check if disabling tracking is consistent with the channel state machine
}
@@ -415,7 +409,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
current_synchro_data.Prompt_Q = static_cast<double>((d_correlator_outs[1]).imag());
// Tracking_timestamp_secs is aligned with the CURRENT PRN start sample
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter+d_current_prn_length_samples) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter + d_current_prn_length_samples) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
current_synchro_data.Rem_code_phase_secs = d_rem_code_phase_samples / static_cast<double>(d_fs_in);
current_synchro_data.Carrier_phase_rads = d_acc_carrier_phase_rad;
current_synchro_data.Carrier_Doppler_hz = d_carrier_doppler_hz;
@@ -430,7 +424,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
d_correlator_outs[n] = gr_complex(0,0);
}
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter+d_current_prn_length_samples) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
current_synchro_data.Tracking_timestamp_secs = (static_cast<double>(d_sample_counter + d_current_prn_length_samples) + static_cast<double>(d_rem_code_phase_samples)) / static_cast<double>(d_fs_in);
current_synchro_data.Rem_code_phase_secs = d_rem_code_phase_samples / static_cast<double>(d_fs_in);
current_synchro_data.System = {'G'};
}
@@ -460,7 +454,7 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
d_dump_file.write(reinterpret_cast<char*>(&prompt_I), sizeof(float));
d_dump_file.write(reinterpret_cast<char*>(&prompt_Q), sizeof(float));
// PRN start sample stamp
tmp_long = d_sample_counter+d_current_prn_length_samples;
tmp_long = d_sample_counter + d_current_prn_length_samples;
d_dump_file.write(reinterpret_cast<char*>(&tmp_long), sizeof(unsigned long int));
// accumulated carrier phase
d_dump_file.write(reinterpret_cast<char*>(&d_acc_carrier_phase_rad), sizeof(double));
@@ -469,11 +463,11 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_doppler_hz), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_code_freq_chips), sizeof(double));
//PLL commands
// PLL commands
d_dump_file.write(reinterpret_cast<char*>(&carr_error_hz), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&d_carrier_doppler_hz), sizeof(double));
//DLL commands
// DLL commands
d_dump_file.write(reinterpret_cast<char*>(&code_error_chips), sizeof(double));
d_dump_file.write(reinterpret_cast<char*>(&code_error_filt_chips), sizeof(double));
@@ -494,9 +488,9 @@ int Gps_L1_Ca_Dll_Pll_Tracking_cc::general_work (int noutput_items __attribute__
}
consume_each(d_current_prn_length_samples); // this is necessary in gr::block derivates
d_sample_counter += d_current_prn_length_samples; //count for the processed samples
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
return 1; // output tracking result ALWAYS even in the case of d_enable_tracking==false
}

1
src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_tracking_cc.h
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@@ -139,7 +139,6 @@ private:
double d_carrier_phase_step_rad;
double d_acc_carrier_phase_rad;
double d_code_phase_samples;
double d_acc_code_phase_secs;
//PRN period in samples
int d_current_prn_length_samples;