gnss-sdr/src/core/system_parameters/beidou_dnav_navigation_message.h

/*!
 * \file beidou_dnav_navigation_message.h
 * \brief  Interface of a BeiDou DNAV Data message decoder
 * \author Sergi Segura, 2018. sergi.segura.munoz(at)gmail.com
 * \author Damian Miralles, 2018. dmiralles2009@gmail.com
 *
 * -------------------------------------------------------------------------
 *
 * Copyright (C) 2010-2019  (see AUTHORS file for a list of contributors)
 *
 * GNSS-SDR is a software defined Global Navigation
 *          Satellite Systems receiver
 *
 * This file is part of GNSS-SDR.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * -------------------------------------------------------------------------
 */


#ifndef GNSS_SDR_BEIDOU_DNAV_NAVIGATION_MESSAGE_H
#define GNSS_SDR_BEIDOU_DNAV_NAVIGATION_MESSAGE_H


#include "Beidou_B1I.h"
#include "Beidou_B3I.h"
#include "Beidou_DNAV.h"
#include "beidou_dnav_almanac.h"
#include "beidou_dnav_ephemeris.h"
#include "beidou_dnav_iono.h"
#include "beidou_dnav_utc_model.h"
#include <bitset>
#include <cstdint>
#include <map>
#include <string>
#include <utility>
#include <vector>


/*!
 * \brief This class decodes a BeiDou D1 NAV Data message
 */
class Beidou_Dnav_Navigation_Message
{
public:
    /*!
     * Default constructor
     */
    Beidou_Dnav_Navigation_Message();

    // System flags for data processing
    bool flag_eph_valid{};
    bool flag_utc_model_valid{};
    bool flag_iono_valid{};
    bool flag_d1_sf1{};
    bool flag_d1_sf2{};
    bool flag_d1_sf3{};
    bool flag_d1_sf4{};
    bool flag_d1_sf5{};
    bool flag_new_SOW_available{};
    bool flag_crc_test{};
    double d_previous_aode{};

    bool flag_d1_sf5_p7{};   //!< D1 NAV Message, Subframe 5, Page 09 decoded indicator
    bool flag_d1_sf5_p8{};   //!< D1 NAV Message, Subframe 5, Page 09 decoded indicator
    bool flag_d1_sf5_p9{};   //!< D1 NAV Message, Subframe 5, Page 09 decoded indicator
    bool flag_d1_sf5_p10{};  //!< D1 NAV Message, Subframe 5, Page 10 decoded indicator

    bool flag_sf1_p1{};   //!< D2 NAV Message, Subframe 1, Page 1 decoded indicator
    bool flag_sf1_p2{};   //!< D2 NAV Message, Subframe 1, Page 2 decoded indicator
    bool flag_sf1_p3{};   //!< D2 NAV Message, Subframe 1, Page 3 decoded indicator
    bool flag_sf1_p4{};   //!< D2 NAV Message, Subframe 1, Page 4 decoded indicator
    bool flag_sf1_p5{};   //!< D2 NAV Message, Subframe 1, Page 5 decoded indicator
    bool flag_sf1_p6{};   //!< D2 NAV Message, Subframe 1, Page 6 decoded indicator
    bool flag_sf1_p7{};   //!< D2 NAV Message, Subframe 1, Page 7 decoded indicator
    bool flag_sf1_p8{};   //!< D2 NAV Message, Subframe 1, Page 8 decoded indicator
    bool flag_sf1_p9{};   //!< D2 NAV Message, Subframe 1, Page 9 decoded indicator
    bool flag_sf1_p10{};  //!< D2 NAV Message, Subframe 1, Page 10 decoded indicator

    // broadcast orbit 1
    double d_SOW{};      //!< Time of BeiDou Week of the ephemeris set (taken from subframes SOW) [s]
    double d_SOW_SF1{};  //!< Time of BeiDou Week from HOW word of Subframe 1 [s]
    double d_SOW_SF2{};  //!< Time of BeiDou Week from HOW word of Subframe 2 [s]
    double d_SOW_SF3{};  //!< Time of BeiDou Week from HOW word of Subframe 3 [s]
    double d_SOW_SF4{};  //!< Time of BeiDou Week from HOW word of Subframe 4 [s]
    double d_SOW_SF5{};  //!< Time of BeiDou Week from HOW word of Subframe 5 [s]

    double d_AODE{};
    double d_Crs{};      //!< Amplitude of the Sine Harmonic Correction Term to the Orbit Radius [m]
    double d_Delta_n{};  //!< Mean Motion Difference From Computed Value [semi-circles/s]
    double d_M_0{};      //!< Mean Anomaly at Reference Time [semi-circles]

    // broadcast orbit 2
    double d_Cuc{};           //!< Amplitude of the Cosine Harmonic Correction Term to the Argument of Latitude [rad]
    double d_eccentricity{};  //!< Eccentricity [dimensionless]
    double d_Cus{};           //!< Amplitude of the Sine Harmonic Correction Term to the Argument of Latitude [rad]
    double d_sqrt_A{};        //!< Square Root of the Semi-Major Axis [sqrt(m)]

    // broadcast orbit 3
    double d_Toe_sf2{};  //!< Ephemeris data reference time of week in subframe 2, D1 Message
    double d_Toe_sf3{};  //!< Ephemeris data reference time of week in subframe 3, D1 Message
    double d_Toe{};      //!< Ephemeris data reference time of week in subframe 1, D2 Message
    double d_Toc{};      //!< clock data reference time [s]
    double d_Cic{};      //!< Amplitude of the Cosine Harmonic Correction Term to the Angle of Inclination [rad]
    double d_OMEGA0{};   //!< Longitude of Ascending Node of Orbit Plane at Weekly Epoch [semi-circles]
    double d_Cis{};      //!< Amplitude of the Sine Harmonic Correction Term to the Angle of Inclination [rad]

    // broadcast orbit 4
    double d_i_0{};        //!< Inclination Angle at Reference Time [semi-circles]
    double d_Crc{};        //!< Amplitude of the Cosine Harmonic Correction Term to the Orbit Radius [m]
    double d_OMEGA{};      //!< Argument of Perigee [semi-cicles]
    double d_OMEGA_DOT{};  //!< Rate of Right Ascension [semi-circles/s]

    // broadcast orbit 5
    double d_IDOT{};          //!< Rate of Inclination Angle [semi-circles/s]
    int32_t i_BEIDOU_week{};  //!< BeiDou week number, aka WN [week]

    // broadcast orbit 6
    int32_t i_SV_accuracy{};  //!< User Range Accuracy (URA) index of the SV
    int32_t i_SV_health{};
    double d_TGD1{};  //!< Estimated Group Delay Differential in B1 [s]
    double d_TGD2{};  //!< Estimated Group Delay Differential in B2 [s]
    double d_AODC{};  //!< Age of Data, Clock

    // broadcast orbit 7
    // int32_t i_AODO{};              //!< Age of Data Offset (AODO) term for the navigation message correction table (NMCT) contained in subframe 4 (reference paragraph 20.3.3.5.1.9) [s]

    bool b_fit_interval_flag{};  //!< indicates the curve-fit interval used by the CS (Block II/IIA/IIR/IIR-M/IIF) and SS (Block IIIA) in determining the ephemeris parameters, as follows: 0 = 4 hours, 1 = greater than 4 hours.
    double d_spare1{};
    double d_spare2{};

    double d_A_f0{};  //!< Clock correction parameters. Coefficient 0 of code phase offset model [s]
    double d_A_f1{};  //!< Clock correction parameters. Coefficient 1 of code phase offset model [s/s]
    double d_A_f2{};  //!< Clock correction parameters. Coefficient 2 of code phase offset model [s/s^2]

    // D2 NAV Message Decoding
    uint64_t d_A_f1_msb_bits{};          //!< Clock correction parameters, D2 NAV MSB
    uint64_t d_A_f1_lsb_bits{};          //!< Clock correction parameters, D2 NAV LSB
    uint64_t d_Cuc_msb_bits{};           //!< Amplitude of the Cosine Harmonic Correction Term to the Argument of Latitude [rad]
    uint64_t d_Cuc_lsb_bits{};           //!< Amplitude of the Cosine Harmonic Correction Term to the Argument of Latitude [rad]
    uint64_t d_eccentricity_msb{};       //!< Eccentricity [dimensionless]
    uint64_t d_eccentricity_lsb{};       //!< Eccentricity [dimensionless]
    uint64_t d_Cic_msb_bits{};           //!< Amplitude of the Cosine Harmonic Correction Term to the Argument of Latitude [rad]
    uint64_t d_Cic_lsb_bits{};           //!< Amplitude of the Cosine Harmonic Correction Term to the Argument of Latitude [rad]
    uint64_t d_eccentricity_msb_bits{};  //!< Eccentricity [dimensionless]
    uint64_t d_eccentricity_lsb_bits{};
    uint64_t d_i_0_msb_bits{};        //!< Inclination Angle at Reference Time [semi-circles]
    uint64_t d_i_0_lsb_bits{};        //!< Inclination Angle at Reference Time [semi-circles]
    uint64_t d_OMEGA_msb_bits{};      //!< Argument of Perigee [semi-cicles]
    uint64_t d_OMEGA_lsb_bits{};      //!< Argument of Perigee [semi-cicles]
    uint64_t d_OMEGA_DOT_msb_bits{};  //!< Rate of Right Ascension [semi-circles/s]
    uint64_t d_OMEGA_DOT_lsb_bits{};  //!< Rate of Right Ascension [semi-circles/s]

    // Almanac
    double d_Toa{};                            //!< Almanac reference time [s]
    int32_t i_WN_A{};                          //!< Modulo 256 of the GPS week number to which the almanac reference time (d_Toa) is referenced
    std::map<int32_t, int32_t> almanacHealth;  //!< Map that stores the health information stored in the almanac

    std::map<int32_t, std::string> satelliteBlock;  //!< Map that stores to which block the PRN belongs

    // Flags

    /*! \brief If true, enhanced level of integrity assurance.
     *
     *  If false, indicates that the conveying signal is provided with the legacy level of integrity assurance.
     *  That is, the probability that the instantaneous URE of the conveying signal exceeds 4.42 times the upper bound
     *  value of the current broadcast URA index, for more than 5.2 seconds, without an accompanying alert, is less
     *  than 1E-5 per hour. If true, indicates that the conveying signal is provided with an enhanced level of
     *  integrity assurance. That is, the probability that the instantaneous URE of the conveying signal exceeds 5.73
     *  times the upper bound value of the current broadcast URA index, for more than 5.2 seconds, without an
     *  accompanying alert, is less than 1E-8 per hour.
     */
    bool b_integrity_status_flag{};
    bool b_alert_flag{};         //!< If true, indicates  that the SV URA may be worse than indicated in d_SV_accuracy, use that SV at our own risk.
    bool b_antispoofing_flag{};  //!<  If true, the AntiSpoofing mode is ON in that SV

    // clock terms
    // double d_master_clock{};  // GPS transmission time
    double d_satClkCorr{};  // GPS clock error
    double d_dtr{};         // relativistic clock correction term
    double d_satClkDrift{};

    // satellite positions
    double d_satpos_X{};  //!< Earth-fixed coordinate x of the satellite [m]. Intersection of the IERS Reference Meridian (IRM) and the plane passing through the origin and normal to the Z-axis.
    double d_satpos_Y{};  //!< Earth-fixed coordinate y of the satellite [m]. Completes a right-handed, Earth-Centered, Earth-Fixed orthogonal coordinate system.
    double d_satpos_Z{};  //!< Earth-fixed coordinate z of the satellite [m]. The direction of the IERS (International Earth Rotation and Reference Systems Service) Reference Pole (IRP).

    // satellite identification info
    int32_t i_channel_ID{};
    int32_t i_signal_type{};  //!< BDS: data source (0:unknown,1:B1I,2:B1Q,3:B2I,4:B2Q,5:B3I,6:B3Q)
    uint32_t i_satellite_PRN{};

    // time synchro
    double d_subframe_timestamp_ms{};  // [ms]

    // Ionospheric parameters
    double d_alpha0{};  //!< Coefficient 0 of a cubic equation representing the amplitude of the vertical delay [s]
    double d_alpha1{};  //!< Coefficient 1 of a cubic equation representing the amplitude of the vertical delay [s/semi-circle]
    double d_alpha2{};  //!< Coefficient 2 of a cubic equation representing the amplitude of the vertical delay [s(semi-circle)^2]
    double d_alpha3{};  //!< Coefficient 3 of a cubic equation representing the amplitude of the vertical delay [s(semi-circle)^3]
    double d_beta0{};   //!< Coefficient 0 of a cubic equation representing the period of the model [s]
    double d_beta1{};   //!< Coefficient 1 of a cubic equation representing the period of the model [s/semi-circle]
    double d_beta2{};   //!< Coefficient 2 of a cubic equation representing the period of the model [s(semi-circle)^2]
    double d_beta3{};   //!< Coefficient 3 of a cubic equation representing the period of the model [s(semi-circle)^3]

    // UTC parameters
    double d_A1UTC{};       //!< 1st order term of a model that relates GPS and UTC time [s/s]
    double d_A0UTC{};       //!< Constant of a model that relates GPS and UTC time [s]
    double d_DeltaT_LS{};   //!< delta time due to leap seconds [s]. Number of leap seconds since 6-Jan-1980 as transmitted by the GPS almanac.
    int32_t i_WN_LSF{};     //!< Week number at the end of which the leap second becomes effective [weeks]
    int32_t i_DN{};         //!< Day number (DN) at the end of which the leap second becomes effective [days]
    double d_DeltaT_LSF{};  //!< Scheduled future or recent past (relative to NAV message upload) value of the delta time due to leap seconds [s]
    double d_A1GPS{};
    double d_A0GPS{};
    double d_A1GAL{};
    double d_A0GAL{};
    double d_A1GLO{};
    double d_A0GLO{};

    double d_SQRT_A_ALMANAC{};
    double d_A1_ALMANAC{};
    double d_A0_ALMANAC{};
    double d_OMEGA0_ALMANAC{};
    double d_E_ALMANAC{};
    double d_DELTA_I{};
    double d_TOA{};
    double d_OMEGA_DOT_ALMANAC{};
    double d_OMEGA_ALMANAC{};
    double d_M0_ALMANAC{};
    int32_t almanac_WN{};
    double d_toa2{};

    // Satellite velocity
    double d_satvel_X{};  //!< Earth-fixed velocity coordinate x of the satellite [m]
    double d_satvel_Y{};  //!< Earth-fixed velocity coordinate y of the satellite [m]
    double d_satvel_Z{};  //!< Earth-fixed velocity coordinate z of the satellite [m]

    // public functions

    /*!
     * \brief Obtain a BDS SV Ephemeris class filled with current SV data
     */
    Beidou_Dnav_Ephemeris get_ephemeris();

    /*!
     * \brief Obtain a BDS ionospheric correction parameters class filled with current SV data
     */
    Beidou_Dnav_Iono get_iono();

    /*!
     * \brief Obtain a BDS UTC model parameters class filled with current SV data
     */
    Beidou_Dnav_Utc_Model get_utc_model();

    /*!
     * \brief Decodes the BDS D1 NAV message
     */
    int32_t d1_subframe_decoder(std::string const& subframe);

    /*!
     * \brief Decodes the BDS D2 NAV message
     */
    int32_t d2_subframe_decoder(std::string const& subframe);

    /*!
     * \brief Computes the position of the satellite
     */
    void satellitePosition(double transmitTime);

    /*!
     * \brief Sets (\a d_satClkCorr) according to the User Algorithm for SV Clock Correction
     * and returns the corrected clock
     */
    double sv_clock_correction(double transmitTime);

    /*!
     * \brief Computes the Coordinated Universal Time (UTC) and
     * returns it in [s]
     */
    double utc_time(const double beidoutime_corrected) const;

    bool satellite_validation();

    /*!
     * \brief Returns true if new Ephemeris has arrived. The flag is set to false when the function is executed
     */
    bool have_new_ephemeris();

    /*!
     * \brief Returns true if new Iono model has arrived. The flag is set to false when the function is executed
     */
    bool have_new_iono();

    /*!
     * \brief Returns true if new UTC model has arrived. The flag is set to false when the function is executed
     */
    bool have_new_utc_model();

    /*!
     * \brief Returns true if new UTC model has arrived. The flag is set to false when the function is executed
     */
    bool have_new_almanac();

private:
    uint64_t read_navigation_unsigned(std::bitset<BEIDOU_DNAV_SUBFRAME_DATA_BITS> bits, const std::vector<std::pair<int32_t, int32_t>>& parameter);
    int64_t read_navigation_signed(std::bitset<BEIDOU_DNAV_SUBFRAME_DATA_BITS> bits, const std::vector<std::pair<int32_t, int32_t>>& parameter);
    bool read_navigation_bool(std::bitset<BEIDOU_DNAV_SUBFRAME_DATA_BITS> bits, const std::vector<std::pair<int32_t, int32_t>>& parameter);
    void print_beidou_word_bytes(uint32_t BEIDOU_word);

    /*
     * Accounts for the beginning or end of week crossover
     *
     * \param[in]  -  time in seconds
     * \param[out] -  corrected time, in seconds
     */
    double check_t(double time);
};

#endif