GPSAlmanac.java
/* Copyright 2002-2026 CS GROUP
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* 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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* Unless required by applicable law or agreed to in writing, software
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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;
/**
* This class holds a GPS almanac as read from SEM or YUMA files.
*
* <p>Depending on the source (SEM or YUMA), some fields may be filled in or not.
* An almanac read from a YUMA file doesn't hold SVN number, average URA and satellite
* configuration.</p>
*
* @author Pascal Parraud
* @since 8.0
*
*/
public class GPSAlmanac extends GNSSOrbitalElements<GPSAlmanac> {
/** Source of the almanac. */
private final String source;
/** SVN number. */
private final int svn;
/** Health status. */
private final int health;
/** Average URA. */
private final int ura;
/** Satellite configuration. */
private final int satConfiguration;
/**
* Constructor.
* @param timeScales known time scales
* @param prn PRN number of the satellite
* @param toe time of ephemeris (<em>must</em> be consistent with {@code orbit})
* @param orbit Keplerian orbit in Earth-frozen frame
* @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 source source of the almanac
* @param svn SVN number
* @param health health status
* @param ura average URA
* @param satConfiguration satellite configuration
*/
public GPSAlmanac(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 String source, final int svn,
final int health, final int ura, final int satConfiguration) {
super(GNSSConstants.GPS_AV, GNSSConstants.GPS_WEEK_NB,
timeScales, null, prn,
toe, orbit, aDot, deltaN0, deltaN0Dot, iDot, omegaDot,
cuc, cus, crc, crs, cic, cis, af0, af1, af2, tgd, toc);
this.source = source;
this.svn = svn;
this.health = health;
this.ura = ura;
this.satConfiguration = satConfiguration;
}
/** Constructor from field instance.
* @param <T> type of the field elements
* @param original regular field instance
*/
public <T extends CalculusFieldElement<T>> GPSAlmanac(final FieldGPSAlmanac<T> original) {
super(original);
source = original.getSource();
svn = original.getSVN();
health = original.getHealth();
ura = original.getURA();
satConfiguration = original.getSatConfiguration();
}
/** {@inheritDoc} */
@Override
public <T extends CalculusFieldElement<T>> FieldGPSAlmanac<T>
toField(final FieldKeplerianOrbit<T> orbit,
final T[] nonKeplerian,
final DoubleFunction<T> converter) {
return new FieldGPSAlmanac<>(getAngularVelocity(), getWeeksInCycle(), getTimeScales(),
getType(), getPrn(),
new FieldGNSSDate<>(orbit.getDate().getField(), getTimeOfEphemeris()),
orbit, nonKeplerian,
converter.apply(getTgd()),
new FieldGNSSDate<>(orbit.getDate().getField(), getTimeOfClock()),
getSource(), getSVN(),
getHealth(), getURA(), getSatConfiguration());
}
/** Get the source of this GPS almanac.
* <p>Sources can be SEM or YUMA, when the almanac is read from a file.</p>
* @return the source of this GPS almanac
*/
public String getSource() {
return source;
}
/** Get the satellite "SVN" reference number.
* @return the satellite "SVN" reference number
*/
public int getSVN() {
return svn;
}
/** Get the Health status.
* @return the Health status
*/
public int getHealth() {
return health;
}
/** Get the average URA number.
* @return the average URA number
*/
public int getURA() {
return ura;
}
/** Get the satellite configuration.
* @return the satellite configuration
*/
public int getSatConfiguration() {
return satConfiguration;
}
/** {@inheritDoc} */
@Override
public GPSAlmanacFactory baseFactory(final Frame inertial, final Frame bodyFixed) {
return new GPSAlmanacFactory(getTimeScales(), getTimeOfEphemeris().getSystem(),
inertial, bodyFixed);
}
}