RangeTroposphericDelayModifier.java

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 * CS licenses this file to You under the Apache License, Version 2.0
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 *
 *   http://www.apache.org/licenses/LICENSE-2.0
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package org.orekit.estimation.measurements.modifiers;

import org.orekit.attitudes.FrameAlignedProvider;
import org.orekit.estimation.measurements.EstimatedMeasurement;
import org.orekit.estimation.measurements.EstimatedMeasurementBase;
import org.orekit.estimation.measurements.EstimationModifier;
import org.orekit.estimation.measurements.GroundStation;
import org.orekit.estimation.measurements.Range;
import org.orekit.models.earth.troposphere.DiscreteTroposphericModel;
import org.orekit.propagation.SpacecraftState;

/** Class modifying theoretical range measurement with tropospheric delay.
 * The effect of tropospheric correction on the range is directly computed
 * through the computation of the tropospheric delay.
 *
 * In general, for GNSS, VLBI, ... there is hardly any frequency dependence in the delay.
 * For SLR techniques however, the frequency dependence is sensitive.
 *
 * @author Maxime Journot
 * @author Joris Olympio
 * @since 8.0
 */
public class RangeTroposphericDelayModifier extends BaseRangeTroposphericDelayModifier implements EstimationModifier<Range> {

    /** Constructor.
     *
     * @param model  Tropospheric delay model appropriate for the current range measurement method.
     */
    public RangeTroposphericDelayModifier(final DiscreteTroposphericModel model) {
        super(model);
    }

    /** {@inheritDoc} */
    @Override
    public void modifyWithoutDerivatives(final EstimatedMeasurementBase<Range> estimated) {

        final Range         measurement = estimated.getObservedMeasurement();
        final GroundStation station     = measurement.getStation();

        RangeModifierUtil.modifyWithoutDerivatives(estimated,  station, this::rangeErrorTroposphericModel);


    }

    /** {@inheritDoc} */
    @Override
    public void modify(final EstimatedMeasurement<Range> estimated) {

        final Range           measurement = estimated.getObservedMeasurement();
        final GroundStation   station     = measurement.getStation();
        final SpacecraftState state       = estimated.getStates()[0];

        RangeModifierUtil.modify(estimated, getTropoModel(),
                                 new ModifierGradientConverter(state, 6, new FrameAlignedProvider(state.getFrame())),
                                 station,
                                 this::rangeErrorTroposphericModel,
                                 this::rangeErrorTroposphericModel);


    }

}