BeidouAlmanac.java

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 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * CS licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
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 *   http://www.apache.org/licenses/LICENSE-2.0
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package org.orekit.propagation.analytical.gnss.data;

import org.hipparchus.CalculusFieldElement;
import org.orekit.frames.Frame;
import org.orekit.orbits.FieldKeplerianOrbit;
import org.orekit.orbits.KeplerianOrbit;
import org.orekit.time.FieldGNSSDate;
import org.orekit.time.GNSSDate;
import org.orekit.time.TimeScales;

import java.util.function.DoubleFunction;

/**
 * Class for BeiDou almanac.
 *
 * @see "BeiDou Navigation Satellite System, Signal In Space, Interface Control Document,
 *      Version 2.1, Table 5-12"
 *
 * @author Bryan Cazabonne
 * @since 10.0
 *
 */
public class BeidouAlmanac extends GNSSOrbitalElements<BeidouAlmanac> {

    /** Health status. */
    private final int health;

    /**
     * Build a new almanac.
     * @param timeScales known time scales
     * @param prn        PRN number of the satellite
     * @param orbit      Keplerian orbit in Earth-frozen frame
     * @param toe        time of ephemeris (<em>must</em> be consistent with {@code orbit})
     * @param aDot       change rate in semi-major axis (m/s)
     * @param deltaN0    delta of satellite mean motion
     * @param deltaN0Dot change rate in Δn₀
     * @param iDot       inclination rate (rad/s)
     * @param omegaDot   rate of right ascension (rad/s)
     * @param cuc        amplitude of the cosine harmonic correction term to the argument of latitude
     * @param cus        amplitude of the sine harmonic correction term to the argument of latitude
     * @param crc        amplitude of the cosine harmonic correction term to the orbit radius
     * @param crs        amplitude of the sine harmonic correction term to the orbit radius
     * @param cic        amplitude of the cosine harmonic correction term to the inclination
     * @param cis        amplitude of the sine harmonic correction term to the inclination
     * @param af0        zero-th order clock correction (s)
     * @param af1        first order clock correction (s/s)
     * @param af2        second order clock correction (s/s²)
     * @param tgd        group delay differential TGD for L1-L2 correction
     * @param toc        time of clock
     * @param health     health status
     */
    public BeidouAlmanac(final TimeScales timeScales, final int prn,
                         final GNSSDate toe, final KeplerianOrbit orbit,
                         final double aDot, final double deltaN0, final double deltaN0Dot,
                         final double iDot, final double omegaDot,
                         final double cuc, final double cus,
                         final double crc, final double crs,
                         final double cic, final double cis,
                         final double af0, final double af1, final double af2,
                         final double tgd, final GNSSDate toc, final int health) {
        super(GNSSConstants.BEIDOU_AV, GNSSConstants.BEIDOU_WEEK_NB, timeScales, null, prn,
              toe, orbit, aDot, deltaN0, deltaN0Dot, iDot, omegaDot,
              cuc, cus, crc, crs, cic, cis, af0, af1, af2, tgd, toc);
        this.health = health;
    }

    /** Constructor from field instance.
     * @param <T> type of the field elements
     * @param original regular field instance
     */
    public <T extends CalculusFieldElement<T>> BeidouAlmanac(final FieldBeidouAlmanac<T> original) {
        super(original);
        health = original.getHealth();
    }

    /** {@inheritDoc} */
    @Override
    public <T extends CalculusFieldElement<T>>
        FieldBeidouAlmanac<T> toField(final FieldKeplerianOrbit<T> orbit,
                                      final T[] nonKeplerian,
                                      final DoubleFunction<T> converter) {
        return new FieldBeidouAlmanac<>(getAngularVelocity(), getWeeksInCycle(), getTimeScales(),
                                        getType(), getPrn(),
                                        new FieldGNSSDate<>(orbit.getDate().getField(), getTimeOfEphemeris()),
                                        orbit, nonKeplerian,
                                        converter.apply( getTgd()),
                                        new FieldGNSSDate<>(orbit.getDate().getField(), getTimeOfClock()),
                                        getHealth());
    }

    /** Get the Health status.
     * @return the Health status
     */
    public int getHealth() {
        return health;
    }

    /** {@inheritDoc} */
    @Override
    public BeidouAlmanacFactory baseFactory(final Frame inertial, final Frame bodyFixed) {
        return new BeidouAlmanacFactory(getTimeScales(), getTimeOfEphemeris().getSystem(),
                                        inertial, bodyFixed);
    }

}