BistaticRangeRateBuilder.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
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 *
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package org.orekit.estimation.measurements.generation;

import org.hipparchus.random.CorrelatedRandomVectorGenerator;
import org.orekit.estimation.measurements.BistaticRangeRate;
import org.orekit.estimation.measurements.GroundStation;
import org.orekit.estimation.measurements.ObservableSatellite;
import org.orekit.propagation.sampling.OrekitStepInterpolator;
import org.orekit.time.AbsoluteDate;

import java.util.Map;

/** Builder for {@link BistaticRangeRate} measurements.
 * @author Pascal Parraud
 * @since 11.2
 */
public class BistaticRangeRateBuilder extends AbstractMeasurementBuilder<BistaticRangeRate> {

    /** Emitter ground station. */
    private final GroundStation emitter;

    /** Receiver ground station. */
    private final GroundStation receiver;

    /** Simple constructor.
     * @param noiseSource noise source, may be null for generating perfect measurements
     * @param emitter emitter ground station
     * @param receiver receiver ground station, from which measurement is performed
     * @param sigma theoretical standard deviation
     * @param baseWeight base weight
     * @param satellite satellite related to this builder
     */
    public BistaticRangeRateBuilder(final CorrelatedRandomVectorGenerator noiseSource,
                                    final GroundStation emitter, final GroundStation receiver,
                                    final double sigma, final double baseWeight,
                                    final ObservableSatellite satellite) {
        super(noiseSource, sigma, baseWeight, satellite);
        this.emitter  = emitter;
        this.receiver = receiver;
    }

    /** {@inheritDoc} */
    @Override
    protected BistaticRangeRate buildObserved(final AbsoluteDate date,
                                              final Map<ObservableSatellite, OrekitStepInterpolator> interpolators) {
        return new BistaticRangeRate(emitter, receiver, date, 0.0,
                                     getTheoreticalStandardDeviation()[0],
                                     getBaseWeight()[0], getSatellites()[0]);
    }

}