BeidouGeo.java

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package org.orekit.gnss.attitude;

import org.hipparchus.CalculusFieldElement;
import org.orekit.frames.Frame;
import org.orekit.time.AbsoluteDate;
import org.orekit.utils.ExtendedPositionProvider;
import org.orekit.utils.TimeStampedAngularCoordinates;
import org.orekit.utils.TimeStampedFieldAngularCoordinates;

/**
 * Attitude providers for Beidou geostationary orbit navigation satellites.
 * @author Luc Maisonobe Java translation
 * @since 9.2
 */
public class BeidouGeo extends AbstractGNSSAttitudeProvider {

    /** Simple constructor.
     * @param validityStart start of validity for this provider
     * @param validityEnd end of validity for this provider
     * @param sun provider for Sun position
     * @param inertialFrame inertial frame where velocity are computed
     */
    public BeidouGeo(final AbsoluteDate validityStart, final AbsoluteDate validityEnd,
                     final ExtendedPositionProvider sun, final Frame inertialFrame) {
        super(validityStart, validityEnd, sun, inertialFrame);
    }

    /** {@inheritDoc} */
    @Override
    protected TimeStampedAngularCoordinates correctedYaw(final GNSSAttitudeContext context) {

        // geostationary Beidou spacecraft are always in Orbit Normal (ON) yaw
        return context.orbitNormalYaw();

    }

    /** {@inheritDoc} */
    @Override
    protected  <T extends CalculusFieldElement<T>> TimeStampedFieldAngularCoordinates<T> correctedYaw(final GNSSFieldAttitudeContext<T> context) {

        // geostationary Beidou spacecraft are always in Orbit Normal (ON) yaw
        return context.orbitNormalYaw();

    }

}