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bug_fix: Fixes bugs in telemetry decoding interface

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Fixes several bugs with the telemetry decoder interface and clean up the
code with unused methods and members of the ephemeris object
This commit is contained in:
Damian Miralles 2017-08-23 15:16:07 -07:00 committed by Damian Miralles
parent 305a81a413
commit 85f7e333bb
7 changed files with 80 additions and 798 deletions
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63
src/algorithms/PVT/libs/rinex_printer.cc
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@ -633,6 +633,8 @@ void Rinex_Printer::rinex_nav_header(std::fstream& out, const Gps_Iono& gps_iono
void Rinex_Printer::rinex_nav_header(std::fstream& out, const Galileo_Iono& galileo_iono, const Galileo_Utc_Model& galileo_utc_model, const Galileo_Almanac& galileo_almanac, const Glonass_Gnav_Utc_Model& glonass_gnav_utc_model, const Glonass_Gnav_Almanac& glonass_gnav_almanac)
{
if(glonass_gnav_almanac.i_satellite_freq_channel){} //Avoid compiler warning
//Avoid compiler warning, there is not time system correction between Galileo and GLONASS
if(galileo_almanac.A_0G_10){}
std::string line;
stringVersion = "3.02";
version = 3;
@ -2047,6 +2049,8 @@ void Rinex_Printer::update_nav_header(std::fstream& out, const Gps_Iono& gps_ion
void Rinex_Printer::update_nav_header(std::fstream& out, const Galileo_Iono& galileo_iono, const Galileo_Utc_Model& galileo_utc_model, const Galileo_Almanac& galileo_almanac, const Glonass_Gnav_Utc_Model& glonass_gnav_utc_model, const Glonass_Gnav_Almanac& glonass_gnav_almanac)
{
if(glonass_gnav_almanac.i_satellite_freq_channel){} //Avoid compiler warning
//Avoid compiler warning, there is not time system correction between Galileo and GLONASS
if(galileo_almanac.A_0G_10){}
std::vector<std::string> data;
std::string line_aux;
@ -3035,7 +3039,7 @@ void Rinex_Printer::log_rinex_nav(std::fstream& out, const std::map<int, Galileo
}
void Rinex_Printer::rinex_obs_header(std::fstream& out, const Glonass_Gnav_Ephemeris& eph, const double d_TOW_first_observation, const std::string bands)
void Rinex_Printer::rinex_obs_header(std::fstream& out, const Glonass_Gnav_Ephemeris& eph, const double d_TOW_first_observation, const std::string glonass_bands)
{
if(eph.d_m){} //Avoid compiler warning
std::string line;
@ -3203,23 +3207,43 @@ void Rinex_Printer::rinex_obs_header(std::fstream& out, const Glonass_Gnav_Ephem
numberTypesObservations = 4;
strm << numberTypesObservations;
line += Rinex_Printer::rightJustify(strm.str(), 3);
// per type of observation
// GLONASS L1 PSEUDORANGE
line += std::string(1, ' ');
line += observationType["PSEUDORANGE"];
line += observationCode["GLONASS_G1_CA"];
// GLONASS L1 PHASE
line += std::string(1, ' ');
line += observationType["CARRIER_PHASE"];
line += observationCode["GLONASS_G1_CA"];
// GLONASS DOPPLER L1
line += std::string(1, ' ');
line += observationType["DOPPLER"];
line += observationCode["GLONASS_G1_CA"];
// GLONASS L1 CA SIGNAL STRENGTH
line += std::string(1, ' ');
line += observationType["SIGNAL_STRENGTH"];
line += observationCode["GLONASS_G1_CA"];
std::string signal_ = "1C";
std::size_t found_1C = glonass_bands.find(signal_);
signal_ = "2C";
std::size_t found_2C = glonass_bands.find(signal_);
if(found_1C != std::string::npos)
{
line += std::string(1, ' ');
line += observationType["PSEUDORANGE"];
line += observationCode["GLONASS_G1_CA"];
line += std::string(1, ' ');
line += observationType["CARRIER_PHASE"];
line += observationCode["GLONASS_G1_CA"];
line += std::string(1, ' ');
line += observationType["DOPPLER"];
line += observationCode["GLONASS_G1_CA"];
line += std::string(1, ' ');
line += observationType["SIGNAL_STRENGTH"];
line += observationCode["GLONASS_G1_CA"];
}
if(found_2C != std::string::npos)
{
line += std::string(1, ' ');
line += observationType["PSEUDORANGE"];
line += observationCode["GLONASS_G2_CA"];
line += std::string(1, ' ');
line += observationType["CARRIER_PHASE"];
line += observationCode["GLONASS_G2_CA"];
line += std::string(1, ' ');
line += observationType["DOPPLER"];
line += observationCode["GLONASS_G2_CA"];
line += std::string(1, ' ');
line += observationType["SIGNAL_STRENGTH"];
line += observationCode["GLONASS_G2_CA"];
}
line += std::string(60-line.size(), ' ');
line += Rinex_Printer::leftJustify("SYS / # / OBS TYPES", 20);
@ -5382,6 +5406,9 @@ void Rinex_Printer::log_rinex_obs(std::fstream& out, const Glonass_Gnav_Ephemeri
// RINEX observations timestamps are GPS timestamps.
std::string line;
// Avoid compiler warning
if(glonass_band.size()){}
boost::posix_time::ptime p_glonass_time = Rinex_Printer::compute_GLONASS_time(eph, obs_time);
std::string timestring = boost::posix_time::to_iso_string(p_glonass_time);
//double utc_t = nav_msg.utc_time(nav_msg.sv_clock_correction(obs_time));

86
src/algorithms/telemetry_decoder/gnuradio_blocks/glonass_l1_ca_telemetry_decoder_cc.cc
View File

@ -69,19 +69,21 @@ glonass_l1_ca_telemetry_decoder_cc::glonass_l1_ca_telemetry_decoder_cc(
d_dump = dump;
d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
LOG(INFO) << "Initializing GLONASS L1 CA TELEMETRY PROCESSING";
// TODO. WHAT IS THIS?
// Define the number of sampes per symbol. Notice that GLONASS has to rates,
//one for the navigation data and the other for the preamble information
d_samples_per_symbol = ( GLONASS_L1_CODE_CHIP_RATE_HZ / GLONASS_L1_CA_CODE_LENGTH_CHIPS ) / GLONASS_L1_CA_SYMBOL_RATE_BPS;
// set the preamble
// Set the preamble information
unsigned short int preambles_bits[GLONASS_GNAV_PREAMBLE_LENGTH_BITS] = GLONASS_GNAV_PREAMBLE;
d_symbols_per_preamble = GLONASS_GNAV_PREAMBLE_LENGTH_BITS * d_samples_per_symbol;
// Since preamble rate is different than navigation data rate we use a constant
d_symbols_per_preamble = GLONASS_GNAV_PREAMBLE_LENGTH_SYMBOLS;
memcpy((unsigned short int*)this->d_preambles_bits, (unsigned short int*)preambles_bits, GLONASS_GNAV_PREAMBLE_LENGTH_BITS*sizeof(unsigned short int));
// preamble bits to sampled symbols
d_preambles_symbols = (signed int*)malloc(sizeof(signed int) * d_symbols_per_preamble);
int n = 0;
for (int i = 0; i < GLONASS_GNAV_PREAMBLE_LENGTH_BITS; i++)
for (int i = 0; i < GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_PREAMBLE_BIT; i++)
{
for (unsigned int j = 0; j < d_samples_per_symbol; j++)
{
@ -130,40 +132,26 @@ glonass_l1_ca_telemetry_decoder_cc::~glonass_l1_ca_telemetry_decoder_cc()
}
void glonass_l1_ca_telemetry_decoder_cc::decode_string(double *page_part_symbols,int frame_length)
void glonass_l1_ca_telemetry_decoder_cc::decode_string(double *frame_symbols,int frame_length)
{
double page_part_symbols_deint[frame_length];
// 2. Viterbi decoder
// 2.1 Take into account the NOT gate in G2 polynomial (Galileo ICD Figure 13, FEC encoder)
// 2.2 Take into account the possible inversion of the polarity due to PLL lock at 180<38>
for (int i = 0; i < frame_length; i++)
// 1. Transform from symbols to bits
std::string frame_string;
for(int i = 0; i < (frame_length); i++)
{
if ((i + 1) % 2 == 0)
if (frame_symbols[i] > 0)
{
page_part_symbols_deint[i] = -page_part_symbols_deint[i];
}
}
int page_part_bits[frame_length/2];
viterbi_decoder(page_part_symbols_deint, page_part_bits);
// 3. Call the Galileo page decoder
std::string page_String;
for(int i = 0; i < (frame_length/2); i++)
{
if (page_part_bits[i] > 0)
{
page_String.push_back('1');
frame_string.push_back('1');
}
else
{
page_String.push_back('0');
frame_string.push_back('0');
}
}
// 2. Call the GLONASS GNAV string decoder
d_nav.decode_string(page_String);
// 3. Check operation executed correctly
if(d_nav.flag_CRC_test == true)
{
LOG(INFO) << "GLONASS GNAV CRC correct on channel " << d_channel << " from satellite " << d_satellite;
@ -175,14 +163,11 @@ void glonass_l1_ca_telemetry_decoder_cc::decode_string(double *page_part_symbols
LOG(INFO) << "GLONASS GNAV CRC error on channel " << d_channel << " from satellite " << d_satellite;
}
// 4. Push the new navigation data to the queues
if (d_nav.have_new_ephemeris() == true)
{
// get object for this SV (mandatory)
std::shared_ptr<Glonass_Gnav_Ephemeris> tmp_obj = std::make_shared<Glonass_Gnav_Ephemeris>(d_nav.get_ephemeris());
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
}
@ -196,19 +181,10 @@ void glonass_l1_ca_telemetry_decoder_cc::decode_string(double *page_part_symbols
{
std::shared_ptr<Glonass_Gnav_Almanac> tmp_obj= std::make_shared<Glonass_Gnav_Almanac>(d_nav.get_almanac());
this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
//debug
std::cout << "GLONASS GNAV almanac received!" << std::endl;
DLOG(INFO) << "Current parameters:";
DLOG(INFO) << "d_TOW_at_current_symbol=" << d_TOW_at_current_symbol;
DLOG(INFO) << "d_nav.WN_0=" << d_nav.WN_0;
delta_t = tmp_obj->A_0G_10 + tmp_obj->A_1G_10 * (d_TOW_at_current_symbol - tmp_obj->t_0G_10 + 604800 * (fmod((d_nav.WN_0 - tmp_obj->WN_0G_10), 64)));
DLOG(INFO) << "delta_t=" << delta_t << "[s]";
}
}
int glonass_l1_ca_telemetry_decoder_cc::general_work (int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
@ -226,7 +202,7 @@ int glonass_l1_ca_telemetry_decoder_cc::general_work (int noutput_items __attrib
consume_each(1);
d_flag_preamble = false;
unsigned int required_symbols=GLONASS_GNAV_PAGE_SYMBOLS+d_symbols_per_preamble;
unsigned int required_symbols=GLONASS_GNAV_FRAME_BITS+d_symbols_per_preamble;
if (d_symbol_history.size()>required_symbols)
{
@ -283,7 +259,7 @@ int glonass_l1_ca_telemetry_decoder_cc::general_work (int noutput_items __attrib
// NEW GLONASS string received
// 0. fetch the symbols into an array
int frame_length = GLONASS_GNAV_STRING_SYMBOLS - d_symbols_per_preamble;
double page_part_symbols[frame_length];
double frame_symbols[frame_length];
//******* SYMBOL TO BIT *******
if (d_symbol_history.at(0).Flag_valid_symbol_output == true)
@ -342,36 +318,20 @@ int glonass_l1_ca_telemetry_decoder_cc::general_work (int noutput_items __attrib
if (this->d_flag_preamble == true and d_nav.flag_TOW_set == true)
//update TOW at the preamble instant
{
if(d_nav.flag_TOW_5 == true) //page 5 arrived and decoded, so we are in the odd page (since Tow refers to the even page, we have to add 1 sec)
{
//TOW_5 refers to the even preamble, but when we decode it we are in the odd part, so 1 second later plus the decoding delay
d_TOW_at_current_symbol = d_nav.TOW_5 + GALILEO_INAV_PAGE_PART_SECONDS+((double)required_symbols)*GALILEO_E1_CODE_PERIOD; //-GALILEO_E1_CODE_PERIOD;//+ (double)GALILEO_INAV_PREAMBLE_LENGTH_BITS/(double)GALILEO_TELEMETRY_RATE_BITS_SECOND;
d_nav.flag_TOW_5 = false;
}
d_TOW_at_current_symbol = floor((d_nav.d_TOW + 2*GLONASS_L1_CA_CODE_PERIOD + GLONASS_CA_PREAMBLE_DURATION_S)*1000.0)/1000.0;
else if(d_nav.flag_TOW_6 == true) //page 6 arrived and decoded, so we are in the odd page (since Tow refers to the even page, we have to add 1 sec)
{
//TOW_6 refers to the even preamble, but when we decode it we are in the odd part, so 1 second later plus the decoding delay
d_TOW_at_current_symbol = d_nav.TOW_6 + GALILEO_INAV_PAGE_PART_SECONDS+((double)required_symbols)*GALILEO_E1_CODE_PERIOD;//-GALILEO_E1_CODE_PERIOD;//+ (double)GALILEO_INAV_PREAMBLE_LENGTH_BITS/(double)GALILEO_TELEMETRY_RATE_BITS_SECOND;
d_nav.flag_TOW_6 = false;
}
else
{
//this page has no timing information
d_TOW_at_current_symbol = d_TOW_at_current_symbol + GALILEO_E1_CODE_PERIOD;// + GALILEO_INAV_PAGE_PART_SYMBOLS*GALILEO_E1_CODE_PERIOD;
}
}
else //if there is not a new preamble, we define the TOW of the current symbol
{
d_TOW_at_current_symbol = d_TOW_at_current_symbol + GALILEO_E1_CODE_PERIOD;
d_TOW_at_current_symbol = d_TOW_at_current_symbol + GLONASS_L1_CA_CODE_PERIOD;
}
//if (d_flag_frame_sync == true and d_nav.flag_TOW_set==true and d_nav.flag_CRC_test == true)
if(d_nav.flag_GGTO_1 == true and d_nav.flag_GGTO_2 == true and d_nav.flag_GGTO_3 == true and d_nav.flag_GGTO_4 == true) //all GGTO parameters arrived
{
delta_t = d_nav.A_0G_10 + d_nav.A_1G_10 * (d_TOW_at_current_symbol - d_nav.t_0G_10 + 604800.0 * (fmod((d_nav.WN_0 - d_nav.WN_0G_10), 64)));
}
// if(d_nav.flag_GGTO_1 == true and d_nav.flag_GGTO_2 == true and d_nav.flag_GGTO_3 == true and d_nav.flag_GGTO_4 == true) //all GGTO parameters arrived
// {
// delta_t = d_nav.A_0G_10 + d_nav.A_1G_10 * (d_TOW_at_current_symbol - d_nav.t_0G_10 + 604800.0 * (fmod((d_nav.WN_0 - d_nav.WN_0G_10), 64)));
// }
if (d_flag_frame_sync == true and d_nav.flag_TOW_set == true)
{

3
src/algorithms/telemetry_decoder/gnuradio_blocks/glonass_l1_ca_telemetry_decoder_cc.h
View File

@ -77,12 +77,13 @@ private:
glonass_l1_ca_make_telemetry_decoder_cc(Gnss_Satellite satellite, bool dump);
glonass_l1_ca_telemetry_decoder_cc(Gnss_Satellite satellite, bool dump);
void decode_word(double *symbols);
void decode_string(double *symbols, int frame_length);
//!< Preamble decoding
unsigned short int d_preambles_bits[GLONASS_GNAV_PREAMBLE_LENGTH_BITS];
int *d_preambles_symbols;
unsigned int d_samples_per_symbol;
unsigned int d_samples_per_preamble_symbol;
int d_symbols_per_preamble;
//!< Storage for incoming data

15
src/core/system_parameters/GLONASS_L1_CA.h
View File

@ -94,13 +94,14 @@ const double GLONASS_STARTOFFSET_ms = 68.802; //[ms] Initial sign. travel time (
const int GLONASS_L1_CA_HISTORY_DEEP = 100;
// NAVIGATION MESSAGE DEMODULATION AND DECODING
#define GLONASS_CA_PREAMBLE {1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0}
const int GLONASS_CA_PREAMBLE_LENGTH_BITS = 30;
const int GLONASS_CA_PREAMBLE_LENGTH_SYMBOLS = 300;
const double GLONASS_CA_PREAMBLE_DURATION_S = 0.3;
const int GLONASS_CA_TELEMETRY_RATE_BITS_SECOND = 50; //!< NAV message bit rate [bits/s]
const int GLONASS_CA_TELEMETRY_SYMBOLS_PER_BIT = 10;
const int GLONASS_CA_TELEMETRY_RATE_SYMBOLS_SECOND = GLONASS_CA_TELEMETRY_RATE_BITS_SECOND*GLONASS_CA_TELEMETRY_SYMBOLS_PER_BIT; //!< NAV message bit rate [symbols/s]
#define GLONASS_GNAV_PREAMBLE {1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0}
const int GLONASS_GNAV_PREAMBLE_LENGTH_BITS = 30;
const int GLONASS_GNAV_PREAMBLE_LENGTH_SYMBOLS = 300;
const double GLONASS_GNAV_PREAMBLE_DURATION_S = 0.3;
const int GLONASS_GNAV_TELEMETRY_RATE_BITS_SECOND = 50; //!< NAV message bit rate [bits/s]
const int GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_BIT = 10;
const int GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_PREAMBLE_BIT = 10;
const int GLONASS_GNAV_TELEMETRY_RATE_SYMBOLS_SECOND = GLONASS_GNAV_TELEMETRY_RATE_BITS_SECOND*GLONASS_GNAV_TELEMETRY_SYMBOLS_PER_BIT; //!< NAV message bit rate [symbols/s]
const int GLONASS_GNAV_PREAMBLE_PERIOD_SYMBOLS = 1700;
const int GLONASS_GNAV_FRAME_BITS = 1725; //!< Number of chips per frame in the GNAV message 15 strings*(85 data bits + 30 time mark bits)[bits]
const int GLONASS_GNAV_FRAME_SECONDS = 30; //!< Subframe duration [seconds]

661
src/core/system_parameters/glonass_gnav_ephemeris.cc
View File

@ -81,18 +81,6 @@ Glonass_Gnav_Ephemeris::Glonass_Gnav_Ephemeris()
d_tau_c = 0.0;
d_TOW = 0.0; // tow of the start of frame
d_WN = 0.0; // week number of the start of frame
// satellite positions
d_satpos_X = 0.0; //!< Earth-fixed coordinate x of the satellite in PZ-90.02 coordinate system [km].
d_satpos_Y = 0.0; //!< Earth-fixed coordinate y of the satellite in PZ-90.02 coordinate system [km]
d_satpos_Z = 0.0; //!< Earth-fixed coordinate z of the satellite in PZ-90.02 coordinate system [km]
// Satellite velocity
d_satvel_X = 0.0; //!< Earth-fixed velocity coordinate x of the satellite in PZ-90.02 coordinate system [km/s]
d_satvel_Y = 0.0; //!< Earth-fixed velocity coordinate y of the satellite in PZ-90.02 coordinate system [km/s]
d_satvel_Z = 0.0; //!< Earth-fixed velocity coordinate z of the satellite in PZ-90.02 coordinate system [km/s]
// Satellite acceleration
d_satacc_X = 0.0; //!< Earth-fixed acceleration coordinate x of the satellite in PZ-90.02 coordinate system [km/s^2]
d_satacc_Y = 0.0; //!< Earth-fixed acceleration coordinate y of the satellite in PZ-90.02 coordinate system [km/s^2]
d_satacc_Z = 0.0; //!< Earth-fixed acceleration coordinate z of the satellite in PZ-90.02 coordinate system [km/s^2]
}
@ -107,122 +95,6 @@ boost::posix_time::ptime Glonass_Gnav_Ephemeris::compute_GLONASS_time(const doub
}
void Glonass_Gnav_Ephemeris::gravitational_perturbations()
{
double T = 0.0;
double sigma_days = 0.0;
double tau_prime = 0.0;
double Omega_moon = 0.0;
double q_moon = 0.0;
double q_sun = 0.0;
double xi_star = 0.0;
double eta_star = 0.0;
double zeta_star = 0.0;
double E_moon = 0.0;
double E_sun = 0.0;
double xi_11 = 0.0;
double xi_12 = 0.0;
double eta_11 = 0.0;
double eta_12 = 0.0;
double zeta_11 = 0.0;
double zeta_12 = 0.0;
double sin_theta_moon = 0.0;
double cos_theta_moon = 0.0;
double theta_moon = 0.0;
double xi_moon_e = 0.0;
double eta_moon_e = 0.0;
double zeta_moon_e = 0.0;
double r_moon_e = 0.0;
double sin_theta_sun = 0.0;
double cos_theta_sun = 0.0;
double theta_sun = 0.0;
double xi_sun_e = 0.0;
double eta_sun_e = 0.0;
double zeta_sun_e = 0.0;
double r_sun_e = 0.0;
double mu_bar_moon = 0.0;
double x_bar_moon = 0.0;
double y_bar_moon = 0.0;
double z_bar_moon = 0.0;
double Delta_o_moon = 0.0;
double mu_bar_sun = 0.0;
double x_bar_sun = 0.0;
double y_bar_sun = 0.0;
double z_bar_sun = 0.0;
double Delta_o_sun = 0.0;
double t_e = 0.0;
//<! Directive Cosine computation
/// \TODO Need to define sigma days
T = (27392.375 + sigma_days + (t_e/86400))/(36525);
tau_prime = GLONASS_TAU_0 + GLONASS_TAU_1 * T;
Omega_moon = GLONASS_MOON_OMEGA_0 + GLONASS_MOON_OMEGA_1*T;
q_moon = GLONASS_MOON_Q0 + GLONASS_MOON_Q1*T;
q_sun = GLONASS_SUN_Q0 + GLONASS_SUN_Q1*T;
xi_star = 1 - (cos(Omega_moon)*cos(Omega_moon))*(1 - cos(GLONASS_MOON_INCLINATION));
eta_star = sin(Omega_moon)*(sin(GLONASS_MOON_INCLINATION));
zeta_star = cos(Omega_moon)*(sin(GLONASS_MOON_INCLINATION));
xi_11 = sin(Omega_moon)*cos(Omega_moon)*(1 - cos(GLONASS_MOON_INCLINATION));
xi_12 = 1 - (sin(Omega_moon)*sin(Omega_moon))*(1 - cos(GLONASS_MOON_INCLINATION));
eta_11 = xi_star*cos(GLONASS_EARTH_INCLINATION) - xi_star*sin(GLONASS_EARTH_INCLINATION);
eta_12 = xi_11*cos(GLONASS_EARTH_INCLINATION) + eta_star*sin(GLONASS_EARTH_INCLINATION);
zeta_11 = xi_star*sin(GLONASS_EARTH_INCLINATION) + zeta_star*cos(GLONASS_EARTH_INCLINATION);
zeta_12 = xi_11*sin(GLONASS_EARTH_INCLINATION) + eta_star*cos(GLONASS_EARTH_INCLINATION);
/// \TODO why is this calling sin(E_moon) in the same line where it is being computed
E_moon = q_moon + GLONASS_MOON_ECCENTRICITY*sin(E_moon);
sin_theta_moon = sqrt(1 - GLONASS_MOON_ECCENTRICITY*GLONASS_MOON_ECCENTRICITY)*sin(E_moon)/(1 - GLONASS_MOON_ECCENTRICITY*cos(E_moon));
cos_theta_moon = cos(E_moon - GLONASS_MOON_ECCENTRICITY)/(1 - GLONASS_MOON_ECCENTRICITY*cos(E_moon));
theta_moon = asin(sin_theta_moon);
xi_moon_e = sin(theta_moon + tau_prime)*xi_11 + cos(theta_moon + tau_prime)*xi_12;
eta_moon_e = sin(theta_moon + tau_prime)*eta_11 + cos(theta_moon + tau_prime)*eta_12;
zeta_moon_e = sin(theta_moon + tau_prime)*zeta_11 + cos(theta_moon + tau_prime)*zeta_12;
r_moon_e = GLONASS_MOON_SEMI_MAJOR_AXIS*(1-GLONASS_MOON_ECCENTRICITY*cos(E_moon));
/// \TODO why is this calling sin(E_moon) in the same line where it is being computed
E_sun = q_sun + GLONASS_SUN_ECCENTRICITY*sin(E_sun);
sin_theta_sun = sqrt(1 - GLONASS_SUN_ECCENTRICITY*GLONASS_SUN_ECCENTRICITY)*sin(E_sun)/(1 - GLONASS_SUN_ECCENTRICITY*cos(E_sun));
cos_theta_sun = cos(E_sun - GLONASS_SUN_ECCENTRICITY)/(1 - GLONASS_SUN_ECCENTRICITY*cos(E_sun));
theta_sun = asin(sin_theta_sun);
xi_sun_e = (cos_theta_sun*cos(GLONASS_SUN_OMEGA) - sin_theta_sun*sin(GLONASS_SUN_OMEGA));
eta_sun_e = (sin_theta_sun*cos(GLONASS_SUN_OMEGA) + cos_theta_sun*sin(GLONASS_SUN_OMEGA))*cos(GLONASS_EARTH_INCLINATION);
zeta_sun_e = (sin_theta_sun*cos(GLONASS_SUN_OMEGA) + cos_theta_sun*sin(GLONASS_SUN_OMEGA))*sin(GLONASS_EARTH_INCLINATION);
r_sun_e = GLONASS_SUN_SEMI_MAJOR_AXIS*(1-GLONASS_SUN_ECCENTRICITY*cos(E_sun));
//<! Gravitational computation
mu_bar_moon = GLONASS_MOON_GM/(r_moon_e*r_moon_e);
x_bar_moon = d_Xn/r_moon_e;
y_bar_moon = d_Yn/r_moon_e;
z_bar_moon = d_Zn/r_moon_e;
Delta_o_moon = sqrt((xi_moon_e - x_bar_moon)*(xi_moon_e - x_bar_moon) + (eta_moon_e - y_bar_moon)*(eta_moon_e - y_bar_moon) + (zeta_moon_e - z_bar_moon)*(zeta_moon_e - z_bar_moon));
mu_bar_sun = GLONASS_MOON_GM/(r_sun_e*r_sun_e);
x_bar_sun = d_Xn/r_sun_e;
y_bar_sun = d_Yn/r_sun_e;
z_bar_sun = d_Zn/r_sun_e;
Delta_o_sun = sqrt((xi_sun_e - x_bar_sun)*(xi_sun_e - x_bar_sun) + (eta_sun_e - y_bar_sun)*(eta_sun_e - y_bar_sun) + (zeta_sun_e - z_bar_sun)*(zeta_sun_e - z_bar_sun));
d_Jx_moon = mu_bar_moon*(xi_moon_e - x_bar_moon)/pow(Delta_o_moon,3.0) - xi_moon_e;
d_Jy_moon = mu_bar_moon*(eta_moon_e - y_bar_moon)/pow(Delta_o_moon,3.0) - eta_moon_e;
d_Jz_moon = mu_bar_moon*(zeta_moon_e - z_bar_moon)/pow(Delta_o_moon,3.0) - zeta_moon_e;
d_Jx_sun = mu_bar_sun*(xi_sun_e - x_bar_sun)/pow(Delta_o_sun,3.0) - xi_sun_e;
d_Jy_sun = mu_bar_sun*(eta_sun_e - y_bar_sun)/pow(Delta_o_sun,3.0) - eta_sun_e;
d_Jz_sun = mu_bar_sun*(zeta_sun_e - z_bar_sun)/pow(Delta_o_sun,3.0) - zeta_sun_e;
}
double Glonass_Gnav_Ephemeris::check_t(double time)
{
double corrTime;
@ -251,536 +123,3 @@ double Glonass_Gnav_Ephemeris::sv_clock_drift(double transmitTime, double timeCo
return d_satClkDrift;
}
// TODO is this the right formula
// compute the relativistic correction term
double Glonass_Gnav_Ephemeris::sv_clock_relativistic_term(double transmitTime)
{
// Compute relativistic correction term
d_dtr = 0.0;
return d_dtr;
}
double Glonass_Gnav_Ephemeris::simplified_satellite_position(double transmitTime)
{
double dt = 0.0;
double tau = 0.0;
double tk = 0.0;
int numberOfIntegrations = 0;
// RK 1
double x_0 = 0.0;
double y_0 = 0.0;
double z_0 = 0.0;
double Vx_0 = 0.0;
double Vy_0 = 0.0;
double Vz_0 = 0.0;
double Ax_0 = 0.0;
double Ay_0 = 0.0;
double Az_0 = 0.0;
double r0 = 0.0;
double r0_2 = 0.0;
double r0_3 = 0.0;
double r0_5 = 0.0;
double dVx_1 = 0.0;
double dVy_1 = 0.0;
double dVz_1 = 0.0;
double dx_1 = 0.0;
double dy_1 = 0.0;
double dz_1 = 0.0;
// Runge-Kutta Integration Stage K2
double x_1 = 0.0;
double y_1 = 0.0;
double z_1 = 0.0;
double Vx_1 = 0.0;
double Vy_1 = 0.0;
double Vz_1 = 0.0;
double r1 = 0.0;
double r1_2 = 0.0;
double r1_3 = 0.0;
double r1_5 = 0.0;
double dVx_2 = 0.0;
double dVy_2 = 0.0;
double dVz_2 = 0.0;
double dx_2 = 0.0;
double dy_2 = 0.0;
double dz_2 = 0.0;
// Runge-Kutta Integration Stage K3
double x_2 = 0.0;
double y_2 = 0.0;
double z_2 = 0.0;
double Vx_2 = 0.0;
double Vy_2 = 0.0;
double Vz_2 = 0.0;
double r2 = 0.0;
double r2_2 = 0.0;
double r2_3 = 0.0;
double r2_5 = 0.0;
double dVx_3 = 0.0;
double dVy_3 = 0.0;
double dVz_3 = 0.0;
double dx_3 = 0.0;
double dy_3 = 0.0;
double dz_3 = 0.0;
// Runge-Kutta Integration Stage K4
double x_3 = 0.0;
double y_3 = 0.0;
double z_3 = 0.0;
double Vx_3 = 0.0;
double Vy_3 = 0.0;
double Vz_3 = 0.0;
double r3 = 0.0;
double r3_2 = 0.0;
double r3_3 = 0.0;
double r3_5 = 0.0;
double dVx_4 = 0.0;
double dVy_4 = 0.0;
double dVz_4 = 0.0;
double dx_4 = 0.0;
double dy_4 = 0.0;
double dz_4 = 0.0;
// Find time difference
dt = check_t(transmitTime - d_t_b);
// Calculate clock correction
d_satClkDrift = -(d_tau_n + /*d_tau_c*/ - d_gamma_n * dt);
// Find integration time
tk = dt - d_satClkDrift;
// Check if to integrate forward or backward
if(tk < 0)
{
tau = -60;
}
else
{
tau = 60;
}
// x,y,z coordinates to meters
x_0 = d_Xn * 1e3;
y_0 = d_Yn * 1e3;
z_0 = d_Zn * 1e3;
// x,y,z velocities to meters/s
Vx_0 = d_VXn * 1e3;
Vy_0 = d_VYn * 1e3;
Vz_0 = d_VZn * 1e3;
// x,y,z accelerations to meters/sec^2
Ax_0 = d_AXn * 1e3;
Ay_0 = d_AYn * 1e3;
Az_0 = d_AZn * 1e3;
for(numberOfIntegrations = tau; numberOfIntegrations < tk+tau; numberOfIntegrations += tau)
{
// Check if last integration step. If last integration step, make one more step that has the remaining time length...
if(fabs(numberOfIntegrations) > fabs(tk))
{
// if there is more time left to integrate...
if(fmod(tk,tau) != 0)
{
tau = fmod(tk,tau);
}
else // otherwise make a zero step.
{
tau = 0;
}
}
// Runge-Kutta Integration Stage K1
r0 = sqrt(x_0*x_0 + y_0*y_0 + z_0*z_0);
r0_2 = r0*r0;
r0_3 = r0*r0*r0;
r0_5 = r0*r0*r0*r0*r0;
dVx_1 = - GLONASS_GM / r0_3 * x_0 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r0_5 * x_0 * (1 - 5 * (z_0*z_0) / r0_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * x_0 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_0 + Ax_0;
dVy_1 = - GLONASS_GM / r0_3 * y_0 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r0_5 * y_0 * (1 - 5 * (z_0*z_0) / r0_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * y_0 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_0 + Ay_0;
dVz_1 = - GLONASS_GM / r0_3 * z_0 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r0_5 * z_0 * (3 - 5 * (z_0*z_0) / r0_2) + Az_0;
dx_1 = Vx_0;
dy_1 = Vy_0;
dz_1 = Vz_0;
// Runge-Kutta Integration Stage K2
Vx_1 = Vx_0 + 1/2 * tau * dVx_1;
Vy_1 = Vy_0 + 1/2 * tau * dVy_1;
Vz_1 = Vz_0 + 1/2 * tau * dVz_1;
x_1 = x_0 + 1/2 * tau * dx_1;
y_1 = y_0 + 1/2 * tau * dy_1;
z_1 = z_0 + 1/2 * tau * dz_1;
r1 = sqrt( x_1*x_1 + y_1*y_1 + z_1*z_1 );
r1_2 = r1*r1;
r1_3 = r1*r1*r1;
r1_5 = r1*r1*r1*r1*r1;
dVx_2 = - GLONASS_GM / r1_3 * x_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * x_1 * (1 - 5 * (z_1*z_1) / r1_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * x_1 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_1 + Ax_0;
dVy_2 = - GLONASS_GM / r1_3 * y_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * y_1 * (1 - 5 * (z_1*z_1) / r1_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * y_1 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_1 + Ay_0;
dVz_2 = - GLONASS_GM / r1_3 * z_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * z_1 * (3 - 5 * (z_1*z_1) / r1_2) + Az_0;
dx_2 = Vx_1;
dy_2 = Vy_1;
dz_2 = Vz_1;
// Runge-Kutta Integration Stage K2
Vx_2 = Vx_0 + 1/2 * tau * dVx_2;
Vy_2 = Vy_0 + 1/2 * tau * dVy_2;
Vz_2 = Vz_0 + 1/2 * tau * dVz_2;
x_2 = x_0 + 1/2 * tau * dx_2;
y_2 = y_0 + 1/2 * tau * dy_2;
z_2 = z_0 + 1/2 * tau * dz_2;
r2 = sqrt( x_2*x_2 + y_2*y_2 + z_2*z_2 );
r2_2 = r2*r2;
r2_3 = r2*r2*r2;
r2_5 = r2*r2*r2*r2*r2;
dVx_3 = - GLONASS_GM / r2_3 * x_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * x_2 * (1 - 5 * (z_2*z_2) / r2_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * x_2 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_2 + Ax_0;
dVy_3 = - GLONASS_GM / r2_3 * y_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * y_2 * (1 - 5 * (z_2*z_2) / r2_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * y_2 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_2 + Ay_0;
dVz_3 = - GLONASS_GM / r2_3 * z_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * z_2 * (3 - 5 * (z_2*z_2) / r2_2) + Az_0;
dx_3 = Vx_2;
dy_3 = Vy_2;
dz_3 = Vz_2;
// Runge-Kutta Integration Stage K3
Vx_3 = Vx_0 + tau * dVx_3;
Vy_3 = Vy_0 + tau * dVy_3;
Vz_3 = Vz_0 + tau * dVz_3;
x_3 = x_0 + tau * dx_3;
y_3 = y_0 + tau * dy_3;
z_3 = z_0 + tau * dz_3;
r3 = sqrt( x_3*x_3 + y_3*y_3 + z_3*z_3 );
r3_2 = r3*r3;
r3_3 = r3*r3*r3;
r3_5 = r3*r3*r3*r3*r3;
dVx_4 = - GLONASS_GM / r3_3 * x_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * x_3 * (1 - 5 * (z_3*z_3) / r3_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * x_3 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_3 + Ax_0;
dVy_4 = - GLONASS_GM / r3_3 * y_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * y_3 * (1 - 5 * (z_3*z_3) / r3_2) + pow(GLONASS_OMEGA_EARTH_DOT, 2) * y_3 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_3 + Ay_0;
dVz_4 = - GLONASS_GM / r3_3 * z_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * z_3 * (3 - 5 * (z_3*z_3) / r3_2) + Az_0;
dx_4 = Vx_3;
dy_4 = Vy_3;
dz_4 = Vz_3;
// Final results showcased here
Vx_0 = Vx_0 + 1/6 * tau * ( dVx_1 + 2 * dVx_2 + 2 * dVx_3 + dVx_4 );
Vy_0 = Vy_0 + 1/6 * tau * ( dVy_1 + 2 * dVy_2 + 2 * dVy_3 + dVy_4 );
Vz_0 = Vz_0 + 1/6 * tau * ( dVz_1 + 2 * dVz_2 + 2 * dVz_3 + dVz_4 );
x_0 = x_0 + 1/6 * tau * ( dx_1 + 2 * dx_2 + 2 * dx_3 + dx_4 );
y_0 = y_0 + 1/6 * tau * ( dy_1 + 2 * dy_2 + 2 * dy_3 + dy_4 );
z_0 = z_0 + 1/6 * tau * ( dz_1 + 2 * dz_2 + 2 * dz_3 + dz_4 );
}
// Reasign position, velocities and accelerations for next integration
d_satpos_X = x_0;
d_satpos_Y = y_0;
d_satpos_Z = z_0;
d_satvel_X = Vx_0;
d_satvel_Y = Vy_0;
d_satvel_Z = Vz_0;
d_satacc_X = d_AXn; // No change in accelerations reported over interval
d_satacc_Y = d_AYn; // No change in accelerations reported over interval
d_satacc_Z = d_AZn; // No change in accelerations reported over interval
// Time from ephemeris reference clock
//tk = check_t(transmitTime - d_Toc);
//double dtr_s = d_A_f0 + d_A_f1 * tk + d_A_f2 * tk * tk;
/* relativity correction */
//dtr_s -= 2.0 * sqrt(GM * GLONASS_a) * d_e_eccentricity * sin(E) / (GPS_C_m_s * GPS_C_m_s);
return 0;
}
double Glonass_Gnav_Ephemeris::satellite_position(double transmitTime)
{
double dt = 0.0;
double tk = 0.0;
double tau = 0.0;
int numberOfIntegrations = 0;
// RK 1
double x_0 = 0.0;
double y_0 = 0.0;
double z_0 = 0.0;
double Vx_0 = 0.0;
double Vy_0 = 0.0;
double Vz_0 = 0.0;
double Ax_0 = 0.0;
double Ay_0 = 0.0;
double Az_0 = 0.0;
double r0 = 0.0;
double r0_2 = 0.0;
double r0_3 = 0.0;
double r0_5 = 0.0;
double dVx_1 = 0.0;
double dVy_1 = 0.0;
double dVz_1 = 0.0;
double dx_1 = 0.0;
double dy_1 = 0.0;
double dz_1 = 0.0;
// Runge-Kutta Integration Stage K2
double x_1 = 0.0;
double y_1 = 0.0;
double z_1 = 0.0;
double Vx_1 = 0.0;
double Vy_1 = 0.0;
double Vz_1 = 0.0;
double r1 = 0.0;
double r1_2 = 0.0;
double r1_3 = 0.0;
double r1_5 = 0.0;
double dVx_2 = 0.0;
double dVy_2 = 0.0;
double dVz_2 = 0.0;
double dx_2 = 0.0;
double dy_2 = 0.0;
double dz_2 = 0.0;
// Runge-Kutta Integration Stage K3
double x_2 = 0.0;
double y_2 = 0.0;
double z_2 = 0.0;
double Vx_2 = 0.0;
double Vy_2 = 0.0;
double Vz_2 = 0.0;
double r2 = 0.0;
double r2_2 = 0.0;
double r2_3 = 0.0;
double r2_5 = 0.0;
double dVx_3 = 0.0;
double dVy_3 = 0.0;
double dVz_3 = 0.0;
double dx_3 = 0.0;
double dy_3 = 0.0;
double dz_3 = 0.0;
// Runge-Kutta Integration Stage K4
double x_3 = 0.0;
double y_3 = 0.0;
double z_3 = 0.0;
double Vx_3 = 0.0;
double Vy_3 = 0.0;
double Vz_3 = 0.0;
double r3 = 0.0;
double r3_2 = 0.0;
double r3_3 = 0.0;
double r3_5 = 0.0;
double dVx_4 = 0.0;
double dVy_4 = 0.0;
double dVz_4 = 0.0;
double dx_4 = 0.0;
double dy_4 = 0.0;
double dz_4 = 0.0;
// Find time difference
dt = check_t(transmitTime - d_t_b);
// Calculate clock correction
d_satClkDrift = -(d_tau_n + /*d_tau_c*/ - d_gamma_n * dt);
// Find integration time
tk = dt - d_satClkDrift;
// Check if to integrate forward or backward
if (tk < 0)
{
tau = -60;
}
else
{
tau = 60;
}
// Coordinates transformation to an inertial reference frame
// x,y,z coordinates to meters
x_0 = d_Xn * 1e3;
y_0 = d_Yn * 1e3;
z_0 = d_Zn * 1e3;
// x,y,z velocities to meters/s
Vx_0 = d_VXn * 1e3;
Vy_0 = d_VYn * 1e3;
Vz_0 = d_VZn * 1e3;
// x,y,z accelerations to meters/sec^2
Ax_0 = d_AXn * 1e3;
Ay_0 = d_AYn * 1e3;
Az_0 = d_AZn * 1e3;
for(numberOfIntegrations = tau; numberOfIntegrations < tk+tau; numberOfIntegrations += tau)
{
// Check if last integration step. If last integration step, make one more step that has the remaining time length...
if(fabs(numberOfIntegrations) > fabs(tk))
{
// if there is more time left to integrate...
if (fmod(tk,tau) != 0)
{
tau = fmod(tk,tau);
}
else // otherwise make a zero step.
{
tau = 0;
}
}
// Runge-Kutta Integration Stage K1
r0 = sqrt(x_0*x_0 + y_0*y_0 + z_0*z_0);
r0_2 = r0*r0;
r0_3 = r0*r0*r0;
r0_5 = r0*r0*r0*r0*r0;
dx_1 = Vx_0;
dy_1 = Vy_0;
dz_1 = Vz_0;
dVx_1 = - GLONASS_GM / r0_3 * x_0 + 3/2 * GLONASS_C20 * GLONASS_GM * pow(GLONASS_EARTH_RADIUS, 2) / r0_5 * x_0 * (1 - 5 * 1 / (z_0*z_0)) + d_Jx_moon + d_Jx_sun;
dVy_1 = - GLONASS_GM / r0_3 * y_0 + 3/2 * GLONASS_C20 * GLONASS_GM * pow(GLONASS_EARTH_RADIUS, 2) / r0_5 * y_0 * (1 - 5 * 1 / (z_0*z_0)) + d_Jy_moon + d_Jy_sun;
dVz_1 = - GLONASS_GM / r0_3 * z_0 + 3/2 * GLONASS_C20 * GLONASS_GM * pow(GLONASS_EARTH_RADIUS, 2) / r0_5 * z_0 * (3 - 5 * 1 / (z_0*z_0)) + d_Jz_moon + d_Jz_sun;
dx_1 = Vx_0;
dy_1 = Vy_0;
dz_1 = Vz_0;
// Runge-Kutta Integration Stage K2
Vx_1 = Vx_0 + 1/2 * tau * dVx_1;
Vy_1 = Vy_0 + 1/2 * tau * dVy_1;
Vz_1 = Vz_0 + 1/2 * tau * dVz_1;
x_1 = x_0 + 1/2 * tau * dx_1;
y_1 = y_0 + 1/2 * tau * dy_1;
z_1 = z_0 + 1/2 * tau * dz_1;
r1 = sqrt( x_1*x_1 + y_1*y_1 + z_1*z_1 );
r1_2 = r1*r1;
r1_3 = r1*r1*r1;
r1_5 = r1*r1*r1*r1*r1;
dVx_2 = - GLONASS_GM / r1_3 * x_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * x_1 * (1 - 5 * (z_1*z_1) / r1_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * x_1 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_1 + Ax_0;
dVy_2 = - GLONASS_GM / r1_3 * y_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * y_1 * (1 - 5 * (z_1*z_1) / r1_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * y_1 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_1 + Ay_0;
dVz_2 = - GLONASS_GM / r1_3 * z_1 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r1_5 * z_1 * (3 - 5 * (z_1*z_1) / r1_2) + Az_0;
dx_2 = Vx_1;
dy_2 = Vy_1;
dz_2 = Vz_1;
// Runge-Kutta Integration Stage K2
Vx_2 = Vx_0 + 1/2 * tau * dVx_2;
Vy_2 = Vy_0 + 1/2 * tau * dVy_2;
Vz_2 = Vz_0 + 1/2 * tau * dVz_2;
x_2 = x_0 + 1/2 * tau * dx_2;
y_2 = y_0 + 1/2 * tau * dy_2;
z_2 = z_0 + 1/2 * tau * dz_2;
r2 = sqrt( x_2*x_2 + y_2*y_2 + z_2*z_2 );
r2_2 = r2*r2;
r2_3 = r2*r2*r2;
r2_5 = r2*r2*r2*r2*r2;
dVx_3 = - GLONASS_GM / r2_3 * x_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * x_2 * (1 - 5 * (z_2*z_2) / r2_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * x_2 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_2 + Ax_0;
dVy_3 = - GLONASS_GM / r2_3 * y_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * y_2 * (1 - 5 * (z_2*z_2) / r2_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * y_2 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_2 + Ay_0;
dVz_3 = - GLONASS_GM / r2_3 * z_2 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r2_5 * z_2 * (3 - 5 * (z_2*z_2) / r2_2) + Az_0;
dx_3 = Vx_2;
dy_3 = Vy_2;
dz_3 = Vz_2;
// Runge-Kutta Integration Stage K3
Vx_3 = Vx_0 + tau * dVx_3;
Vy_3 = Vy_0 + tau * dVy_3;
Vz_3 = Vz_0 + tau * dVz_3;
x_3 = x_0 + tau * dx_3;
y_3 = y_0 + tau * dy_3;
z_3 = z_0 + tau * dz_3;
r3 = sqrt( x_3*x_3 + y_3*y_3 + z_3*z_3 );
r3_2 = r3*r3;
r3_3 = r3*r3*r3;
r3_5 = r3*r3*r3*r3*r3;
dVx_4 = - GLONASS_GM / r3_3 * x_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * x_3 * (1 - 5 * (z_3*z_3) / r3_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * x_3 + 2 * GLONASS_OMEGA_EARTH_DOT * Vy_3 + Ax_0;
dVy_4 = - GLONASS_GM / r3_3 * y_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * y_3 * (1 - 5 * (z_3*z_3) / r3_2) + (GLONASS_OMEGA_EARTH_DOT * GLONASS_OMEGA_EARTH_DOT) * y_3 - 2 * GLONASS_OMEGA_EARTH_DOT * Vx_3 + Ay_0;
dVz_4 = - GLONASS_GM / r3_3 * z_3 - 3/2 * GLONASS_J2 * GLONASS_GM * pow(GLONASS_SEMI_MAJOR_AXIS, 2) / r3_5 * z_3 * (3 - 5 * (z_3*z_3) / r3_2) + Az_0;
dx_4 = Vx_3;
dy_4 = Vy_3;
dz_4 = Vz_3;
// Final results showcased here
d_satvel_X = Vx_0 + 1/6 * tau * ( dVx_1 + 2 * dVx_2 + 2 * dVx_3 + dVx_4 );
d_satvel_Y = Vy_0 + 1/6 * tau * ( dVy_1 + 2 * dVy_2 + 2 * dVy_3 + dVy_4 );
d_satvel_Z = Vz_0 + 1/6 * tau * ( dVz_1 + 2 * dVz_2 + 2 * dVz_3 + dVz_4 );
d_satpos_X = x_0 + 1/6 * tau * ( dx_1 + 2 * dx_2 + 2 * dx_3 + dx_4 );
d_satpos_Y = y_0 + 1/6 * tau * ( dy_1 + 2 * dy_2 + 2 * dy_3 + dy_4 );
d_satpos_Z = z_0 + 1/6 * tau * ( dz_1 + 2 * dz_2 + 2 * dz_3 + dz_4 );
}
// Time from ephemeris reference clock
//tk = check_t(transmitTime - d_Toc);
//double dtr_s = d_A_f0 + d_A_f1 * tk + d_A_f2 * tk * tk;
/* relativity correction */
//dtr_s -= 2.0 * sqrt(GM * GLONASS_a) * d_e_eccentricity * sin(E) / (GPS_C_m_s * GPS_C_m_s);
return d_dtr;
}

48
src/core/system_parameters/glonass_gnav_ephemeris.h
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@ -60,16 +60,6 @@ private:
*/
double check_t(double time);
void gravitational_perturbations();
double d_Jx_moon; //!< Moon gravitational perturbation
double d_Jy_moon; //!< Moon gravitational perturbation
double d_Jz_moon; //!< Moon gravitational perturbation
double d_Jx_sun; //!< Sun gravitational perturbation
double d_Jy_sun; //!< Sun gravitational perturbation
double d_Jz_sun; //!< Sun gravitational perturbation
public:
double d_m; //!< String number within frame [dimensionless]
double d_t_k; //!< GLONASS Time (UTC(SU) + 3 h) referenced to the beginning of the frame within the current day [s]
@ -115,19 +105,6 @@ public:
double d_TOW; // tow of the start of frame
double d_WN; // week number of the start of frame
// satellite positions after RK4 Integration
double d_satpos_X; //!< Earth-fixed coordinate x of the satellite in PZ-90.02 coordinate system [km].
double d_satpos_Y; //!< Earth-fixed coordinate y of the satellite in PZ-90.02 coordinate system [km]
double d_satpos_Z; //!< Earth-fixed coordinate z of the satellite in PZ-90.02 coordinate system [km]
// Satellite velocity after RK4 Integration
double d_satvel_X; //!< Earth-fixed velocity coordinate x of the satellite in PZ-90.02 coordinate system [km/s]
double d_satvel_Y; //!< Earth-fixed velocity coordinate y of the satellite in PZ-90.02 coordinate system [km/s]
double d_satvel_Z; //!< Earth-fixed velocity coordinate z of the satellite in PZ-90.02 coordinate system [km/s]
// Satellite acceleration after RK4 Integration
double d_satacc_X; //!< Earth-fixed acceleration coordinate x of the satellite in PZ-90.02 coordinate system [km/s^2]
double d_satacc_Y; //!< Earth-fixed acceleration coordinate y of the satellite in PZ-90.02 coordinate system [km/s^2]
double d_satacc_Z; //!< Earth-fixed acceleration coordinate z of the satellite in PZ-90.02 coordinate system [km/s^2]
template<class Archive>
/*!
@ -171,37 +148,12 @@ public:
archive & make_nvp("d_l5th_n", d_l5th_n); //!< Health flag for nth satellite; ln = 0 indicates the n-th satellite is helthy, ln = 1 indicates malfunction of this nth satellite [dimensionless]
}
/*!
* \brief Compute the ECEF SV coordinates and ECEF velocity
* Implementation of Algorithm A.3.1.2 in GLONASS ICD v5.1
* and compute the clock bias term including relativistic effect (return value)
* \param transmitTime Time of ephemeris transmission
* \return clock bias of satellite
*/
double simplified_satellite_position(double transmitTime);
/*!
* \brief Compute the ECEF SV coordinates and ECEF velocity
* Implementation of Algorithm A.3.1.1 in GLONASS ICD v5.1
* and compute the clock bias term including relativistic effect (return value)
* \param transmitTime Time of ephemeris transmission
* \return clock bias of satellite
*/
double satellite_position(double transmitTime);
/*!
* \brief Sets (\a d_satClkDrift)and returns the clock drift in seconds according to the User Algorithm for SV Clock Correction
* (IS-GPS-200E, 20.3.3.3.3.1)
*/
double sv_clock_drift(double transmitTime, double timeCorrUTC);
/*!
* \brief Sets (\a d_dtr) and returns the clock relativistic correction term in seconds according to the User Algorithm for SV Clock Correction
* (IS-GPS-200E, 20.3.3.3.3.1)
*/
double sv_clock_relativistic_term(double transmitTime);
/*!
* \brief Computes the GLONASS System Time and returns a boost::posix_time::ptime object
* \ param offset_time Is the start of day offset to compute the time

2
src/core/system_parameters/glonass_gnav_utc_model.h
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@ -1,7 +1,9 @@
/*!
* \file glonass_gnav_utc_model.h
* \brief Interface of a GLONASS GNAV UTC MODEL storage
* \note Code added as part of GSoC 2017 program
* \author Damian Miralles, 2017. dmiralles2009(at)gmail.com
* \see <a href="http://russianspacesystems.ru/wp-content/uploads/2016/08/ICD_GLONASS_eng_v5.1.pdf">GLONASS ICD</a>
*
* -------------------------------------------------------------------------
*