AngularRaDecBuilder.java

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package org.orekit.estimation.measurements.generation;

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

import java.util.Map;

/** Builder for {@link AngularRaDec} measurements.
 * @author Luc Maisonobe
 * @since 9.3
 */
public class AngularRaDecBuilder extends AbstractMeasurementBuilder<AngularRaDec> {

    /** Zero value for initial dummy measurement. */
    private static final double[] ZERO = { 0.0, 0.0 };

    /** Ground station from which measurement is performed. */
    private final GroundStation station;

    /** Reference frame in which the right ascension - declination angles are given. */
    private final Frame referenceFrame;

    /** Simple constructor.
     * @param noiseSource noise source, may be null for generating perfect measurements
     * @param station ground station from which measurement is performed
     * @param referenceFrame Reference frame in which the right ascension - declination angles are given
     * @param sigma theoretical standard deviation
     * @param baseWeight base weight
     * @param satellite satellite related to this builder
     */
    public AngularRaDecBuilder(final CorrelatedRandomVectorGenerator noiseSource,
                               final GroundStation station, final Frame referenceFrame,
                               final double[] sigma, final double[] baseWeight,
                               final ObservableSatellite satellite) {
        super(noiseSource, sigma, baseWeight, satellite);
        this.station        = station;
        this.referenceFrame = referenceFrame;
    }

    /** {@inheritDoc} */
    @Override
    protected AngularRaDec buildObserved(final AbsoluteDate date,
                                         final Map<ObservableSatellite, OrekitStepInterpolator> interpolators) {
        return new AngularRaDec(station, referenceFrame, date, ZERO,
                                getTheoreticalStandardDeviation(),
                                getBaseWeight(), getSatellites()[0]);
    }

}