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Example 16 with GroundStation

use of org.orekit.estimation.measurements.GroundStation in project Orekit by CS-SI.

the class OrbitDeterminationTest method createStationsData.

/**
 * Set up stations.
 * @param parser input file parser
 * @param body central body
 * @return name to station data map
 * @exception OrekitException if some frame transforms cannot be computed
 * @throws NoSuchElementException if input parameters are missing
 */
private Map<String, StationData> createStationsData(final KeyValueFileParser<ParameterKey> parser, final OneAxisEllipsoid body) throws OrekitException, NoSuchElementException {
    final Map<String, StationData> stations = new HashMap<String, StationData>();
    final String[] stationNames = parser.getStringArray(ParameterKey.GROUND_STATION_NAME);
    final double[] stationLatitudes = parser.getAngleArray(ParameterKey.GROUND_STATION_LATITUDE);
    final double[] stationLongitudes = parser.getAngleArray(ParameterKey.GROUND_STATION_LONGITUDE);
    final double[] stationAltitudes = parser.getDoubleArray(ParameterKey.GROUND_STATION_ALTITUDE);
    final boolean[] stationPositionEstimated = parser.getBooleanArray(ParameterKey.GROUND_STATION_POSITION_ESTIMATED);
    final double[] stationRangeSigma = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_SIGMA);
    final double[] stationRangeBias = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_BIAS);
    final double[] stationRangeBiasMin = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_BIAS_MIN);
    final double[] stationRangeBiasMax = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_BIAS_MAX);
    final boolean[] stationRangeBiasEstimated = parser.getBooleanArray(ParameterKey.GROUND_STATION_RANGE_BIAS_ESTIMATED);
    final double[] stationRangeRateSigma = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_RATE_SIGMA);
    final double[] stationRangeRateBias = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_RATE_BIAS);
    final double[] stationRangeRateBiasMin = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_RATE_BIAS_MIN);
    final double[] stationRangeRateBiasMax = parser.getDoubleArray(ParameterKey.GROUND_STATION_RANGE_RATE_BIAS_MAX);
    final boolean[] stationRangeRateBiasEstimated = parser.getBooleanArray(ParameterKey.GROUND_STATION_RANGE_RATE_BIAS_ESTIMATED);
    final double[] stationAzimuthSigma = parser.getAngleArray(ParameterKey.GROUND_STATION_AZIMUTH_SIGMA);
    final double[] stationAzimuthBias = parser.getAngleArray(ParameterKey.GROUND_STATION_AZIMUTH_BIAS);
    final double[] stationAzimuthBiasMin = parser.getAngleArray(ParameterKey.GROUND_STATION_AZIMUTH_BIAS_MIN);
    final double[] stationAzimuthBiasMax = parser.getAngleArray(ParameterKey.GROUND_STATION_AZIMUTH_BIAS_MAX);
    final double[] stationElevationSigma = parser.getAngleArray(ParameterKey.GROUND_STATION_ELEVATION_SIGMA);
    final double[] stationElevationBias = parser.getAngleArray(ParameterKey.GROUND_STATION_ELEVATION_BIAS);
    final double[] stationElevationBiasMin = parser.getAngleArray(ParameterKey.GROUND_STATION_ELEVATION_BIAS_MIN);
    final double[] stationElevationBiasMax = parser.getAngleArray(ParameterKey.GROUND_STATION_ELEVATION_BIAS_MAX);
    final boolean[] stationAzElBiasesEstimated = parser.getBooleanArray(ParameterKey.GROUND_STATION_AZ_EL_BIASES_ESTIMATED);
    final boolean[] stationElevationRefraction = parser.getBooleanArray(ParameterKey.GROUND_STATION_ELEVATION_REFRACTION_CORRECTION);
    final boolean[] stationRangeTropospheric = parser.getBooleanArray(ParameterKey.GROUND_STATION_RANGE_TROPOSPHERIC_CORRECTION);
    for (int i = 0; i < stationNames.length; ++i) {
        // the station itself
        final GeodeticPoint position = new GeodeticPoint(stationLatitudes[i], stationLongitudes[i], stationAltitudes[i]);
        final TopocentricFrame topo = new TopocentricFrame(body, position, stationNames[i]);
        final GroundStation station = new GroundStation(topo);
        station.getEastOffsetDriver().setSelected(stationPositionEstimated[i]);
        station.getNorthOffsetDriver().setSelected(stationPositionEstimated[i]);
        station.getZenithOffsetDriver().setSelected(stationPositionEstimated[i]);
        // range
        final double rangeSigma = stationRangeSigma[i];
        final Bias<Range> rangeBias;
        if (FastMath.abs(stationRangeBias[i]) >= Precision.SAFE_MIN || stationRangeBiasEstimated[i]) {
            rangeBias = new Bias<Range>(new String[] { stationNames[i] + "/range bias" }, new double[] { stationRangeBias[i] }, new double[] { rangeSigma }, new double[] { stationRangeBiasMin[i] }, new double[] { stationRangeBiasMax[i] });
            rangeBias.getParametersDrivers().get(0).setSelected(stationRangeBiasEstimated[i]);
        } else {
            // bias fixed to zero, we don't need to create a modifier for this
            rangeBias = null;
        }
        // range rate
        final double rangeRateSigma = stationRangeRateSigma[i];
        final Bias<RangeRate> rangeRateBias;
        if (FastMath.abs(stationRangeRateBias[i]) >= Precision.SAFE_MIN || stationRangeRateBiasEstimated[i]) {
            rangeRateBias = new Bias<RangeRate>(new String[] { stationNames[i] + "/range rate bias" }, new double[] { stationRangeRateBias[i] }, new double[] { rangeRateSigma }, new double[] { stationRangeRateBiasMin[i] }, new double[] { stationRangeRateBiasMax[i] });
            rangeRateBias.getParametersDrivers().get(0).setSelected(stationRangeRateBiasEstimated[i]);
        } else {
            // bias fixed to zero, we don't need to create a modifier for this
            rangeRateBias = null;
        }
        // angular biases
        final double[] azELSigma = new double[] { stationAzimuthSigma[i], stationElevationSigma[i] };
        final Bias<AngularAzEl> azELBias;
        if (FastMath.abs(stationAzimuthBias[i]) >= Precision.SAFE_MIN || FastMath.abs(stationElevationBias[i]) >= Precision.SAFE_MIN || stationAzElBiasesEstimated[i]) {
            azELBias = new Bias<AngularAzEl>(new String[] { stationNames[i] + "/az bias", stationNames[i] + "/el bias" }, new double[] { stationAzimuthBias[i], stationElevationBias[i] }, azELSigma, new double[] { stationAzimuthBiasMin[i], stationElevationBiasMin[i] }, new double[] { stationAzimuthBiasMax[i], stationElevationBiasMax[i] });
            azELBias.getParametersDrivers().get(0).setSelected(stationAzElBiasesEstimated[i]);
            azELBias.getParametersDrivers().get(1).setSelected(stationAzElBiasesEstimated[i]);
        } else {
            // bias fixed to zero, we don't need to create a modifier for this
            azELBias = null;
        }
        // Refraction correction
        final AngularRadioRefractionModifier refractionCorrection;
        if (stationElevationRefraction[i]) {
            final double altitude = station.getBaseFrame().getPoint().getAltitude();
            final AtmosphericRefractionModel refractionModel = new EarthITU453AtmosphereRefraction(altitude);
            refractionCorrection = new AngularRadioRefractionModifier(refractionModel);
        } else {
            refractionCorrection = null;
        }
        // Tropospheric correction
        final RangeTroposphericDelayModifier rangeTroposphericCorrection;
        if (stationRangeTropospheric[i]) {
            final SaastamoinenModel troposphericModel = SaastamoinenModel.getStandardModel();
            rangeTroposphericCorrection = new RangeTroposphericDelayModifier(troposphericModel);
        } else {
            rangeTroposphericCorrection = null;
        }
        stations.put(stationNames[i], new StationData(station, rangeSigma, rangeBias, rangeRateSigma, rangeRateBias, azELSigma, azELBias, refractionCorrection, rangeTroposphericCorrection));
    }
    return stations;
}
Also used : GroundStation(org.orekit.estimation.measurements.GroundStation) HashMap(java.util.HashMap) EarthITU453AtmosphereRefraction(org.orekit.models.earth.EarthITU453AtmosphereRefraction) TopocentricFrame(org.orekit.frames.TopocentricFrame) AngularRadioRefractionModifier(org.orekit.estimation.measurements.modifiers.AngularRadioRefractionModifier) AtmosphericRefractionModel(org.orekit.models.AtmosphericRefractionModel) Range(org.orekit.estimation.measurements.Range) RangeTroposphericDelayModifier(org.orekit.estimation.measurements.modifiers.RangeTroposphericDelayModifier) GeodeticPoint(org.orekit.bodies.GeodeticPoint) RangeRate(org.orekit.estimation.measurements.RangeRate) GeodeticPoint(org.orekit.bodies.GeodeticPoint) AngularAzEl(org.orekit.estimation.measurements.AngularAzEl) SaastamoinenModel(org.orekit.models.earth.SaastamoinenModel)

Example 17 with GroundStation

use of org.orekit.estimation.measurements.GroundStation in project Orekit by CS-SI.

the class IonoModifierTest method testRangeIonoModifier.

@Test
public void testRangeIonoModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    final RangeIonosphericDelayModifier modifier = new RangeIonosphericDelayModifier(model);
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState refstate = propagator.propagate(date);
        Range range = (Range) measurement;
        EstimatedMeasurement<Range> evalNoMod = range.estimate(12, 17, new SpacecraftState[] { refstate });
        Assert.assertEquals(12, evalNoMod.getIteration());
        Assert.assertEquals(17, evalNoMod.getCount());
        // add modifier
        range.addModifier(modifier);
        boolean found = false;
        for (final EstimationModifier<Range> existing : range.getModifiers()) {
            found = found || existing == modifier;
        }
        Assert.assertTrue(found);
        // 
        EstimatedMeasurement<Range> eval = range.estimate(0, 0, new SpacecraftState[] { refstate });
        Assert.assertEquals(evalNoMod.getStatus(), eval.getStatus());
        eval.setStatus(EstimatedMeasurement.Status.REJECTED);
        Assert.assertEquals(EstimatedMeasurement.Status.REJECTED, eval.getStatus());
        eval.setStatus(evalNoMod.getStatus());
        try {
            eval.getParameterDerivatives(new ParameterDriver("extra", 0, 1, -1, +1));
            Assert.fail("an exception should have been thrown");
        } catch (OrekitIllegalArgumentException oiae) {
            Assert.assertEquals(OrekitMessages.UNSUPPORTED_PARAMETER_NAME, oiae.getSpecifier());
        }
        final double diffMeters = eval.getEstimatedValue()[0] - evalNoMod.getEstimatedValue()[0];
        // TODO: check threshold
        Assert.assertEquals(0.0, diffMeters, 30.0);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) TurnAroundRangeIonosphericDelayModifier(org.orekit.estimation.measurements.modifiers.TurnAroundRangeIonosphericDelayModifier) RangeIonosphericDelayModifier(org.orekit.estimation.measurements.modifiers.RangeIonosphericDelayModifier) TurnAroundRange(org.orekit.estimation.measurements.TurnAroundRange) Range(org.orekit.estimation.measurements.Range) ParameterDriver(org.orekit.utils.ParameterDriver) AbsoluteDate(org.orekit.time.AbsoluteDate) OrekitIllegalArgumentException(org.orekit.errors.OrekitIllegalArgumentException) SpacecraftState(org.orekit.propagation.SpacecraftState) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeMeasurementCreator(org.orekit.estimation.measurements.RangeMeasurementCreator) TurnAroundRangeMeasurementCreator(org.orekit.estimation.measurements.TurnAroundRangeMeasurementCreator) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 18 with GroundStation

use of org.orekit.estimation.measurements.GroundStation in project Orekit by CS-SI.

the class IonoModifierTest method testKlobucharIonoModel.

@Test
public void testKlobucharIonoModel() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    for (final ObservedMeasurement<?> measurement : measurements) {
        // parameter corresponding to station position offset
        final GroundStation station = ((Range) measurement).getStation();
        final AbsoluteDate date = ((Range) measurement).getDate();
        final SpacecraftState state = propagator.propagate(date);
        final Vector3D position = state.getPVCoordinates().getPosition();
        // 
        final GeodeticPoint geo = station.getBaseFrame().getPoint();
        // elevation
        final double elevation = station.getBaseFrame().getElevation(position, state.getFrame(), state.getDate());
        // elevation
        final double azimuth = station.getBaseFrame().getAzimuth(position, state.getFrame(), state.getDate());
        double delayMeters = model.pathDelay(date, geo, elevation, azimuth);
        final double epsilon = 1e-6;
        Assert.assertTrue(Precision.compareTo(delayMeters, 15., epsilon) < 0);
        Assert.assertTrue(Precision.compareTo(delayMeters, 0., epsilon) > 0);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) TurnAroundRange(org.orekit.estimation.measurements.TurnAroundRange) Range(org.orekit.estimation.measurements.Range) AbsoluteDate(org.orekit.time.AbsoluteDate) SpacecraftState(org.orekit.propagation.SpacecraftState) Vector3D(org.hipparchus.geometry.euclidean.threed.Vector3D) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeMeasurementCreator(org.orekit.estimation.measurements.RangeMeasurementCreator) TurnAroundRangeMeasurementCreator(org.orekit.estimation.measurements.TurnAroundRangeMeasurementCreator) GeodeticPoint(org.orekit.bodies.GeodeticPoint) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 19 with GroundStation

use of org.orekit.estimation.measurements.GroundStation in project Orekit by CS-SI.

the class TropoModifierTest method testAngularTropoModifier.

@Test
public void testAngularTropoModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect angular measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new AngularAzElMeasurementCreator(context), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    final AngularTroposphericDelayModifier modifier = new AngularTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState refState = propagator.propagate(date);
        AngularAzEl angular = (AngularAzEl) measurement;
        EstimatedMeasurement<AngularAzEl> evalNoMod = angular.estimate(0, 0, new SpacecraftState[] { refState });
        // add modifier
        angular.addModifier(modifier);
        // 
        EstimatedMeasurement<AngularAzEl> eval = angular.estimate(0, 0, new SpacecraftState[] { refState });
        final double diffAz = MathUtils.normalizeAngle(eval.getEstimatedValue()[0], evalNoMod.getEstimatedValue()[0]) - evalNoMod.getEstimatedValue()[0];
        final double diffEl = MathUtils.normalizeAngle(eval.getEstimatedValue()[1], evalNoMod.getEstimatedValue()[1]) - evalNoMod.getEstimatedValue()[1];
        // TODO: check threshold
        Assert.assertEquals(0.0, diffAz, 5.0e-5);
        Assert.assertEquals(0.0, diffEl, 5.0e-6);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) AbsoluteDate(org.orekit.time.AbsoluteDate) SpacecraftState(org.orekit.propagation.SpacecraftState) AngularTroposphericDelayModifier(org.orekit.estimation.measurements.modifiers.AngularTroposphericDelayModifier) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) AngularAzElMeasurementCreator(org.orekit.estimation.measurements.AngularAzElMeasurementCreator) AngularAzEl(org.orekit.estimation.measurements.AngularAzEl) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 20 with GroundStation

use of org.orekit.estimation.measurements.GroundStation in project Orekit by CS-SI.

the class TropoModifierTest method testRangeRateTropoModifier.

@Test
public void testRangeRateTropoModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeRateMeasurementCreator(context, false), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    final RangeRateTroposphericDelayModifier modifier = new RangeRateTroposphericDelayModifier(SaastamoinenModel.getStandardModel(), false);
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState refState = propagator.propagate(date);
        RangeRate rangeRate = (RangeRate) measurement;
        EstimatedMeasurement<RangeRate> evalNoMod = rangeRate.estimate(0, 0, new SpacecraftState[] { refState });
        // add modifier
        rangeRate.addModifier(modifier);
        // 
        EstimatedMeasurement<RangeRate> eval = rangeRate.estimate(0, 0, new SpacecraftState[] { refState });
        final double diffMetersSec = eval.getEstimatedValue()[0] - evalNoMod.getEstimatedValue()[0];
        final double epsilon = 1e-6;
        Assert.assertTrue(Precision.compareTo(diffMetersSec, 0.01, epsilon) < 0);
        Assert.assertTrue(Precision.compareTo(diffMetersSec, -0.01, epsilon) > 0);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) AbsoluteDate(org.orekit.time.AbsoluteDate) SpacecraftState(org.orekit.propagation.SpacecraftState) RangeRateTroposphericDelayModifier(org.orekit.estimation.measurements.modifiers.RangeRateTroposphericDelayModifier) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeRate(org.orekit.estimation.measurements.RangeRate) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) RangeRateMeasurementCreator(org.orekit.estimation.measurements.RangeRateMeasurementCreator) Test(org.junit.Test)

Aggregations

GroundStation (org.orekit.estimation.measurements.GroundStation)24 SpacecraftState (org.orekit.propagation.SpacecraftState)19 AbsoluteDate (org.orekit.time.AbsoluteDate)14 Test (org.junit.Test)10 Context (org.orekit.estimation.Context)10 ObservedMeasurement (org.orekit.estimation.measurements.ObservedMeasurement)10 Propagator (org.orekit.propagation.Propagator)10 NumericalPropagatorBuilder (org.orekit.propagation.conversion.NumericalPropagatorBuilder)10 AngularAzEl (org.orekit.estimation.measurements.AngularAzEl)9 Range (org.orekit.estimation.measurements.Range)8 ParameterDriver (org.orekit.utils.ParameterDriver)8 RangeRate (org.orekit.estimation.measurements.RangeRate)7 TurnAroundRange (org.orekit.estimation.measurements.TurnAroundRange)7 TurnAroundRangeMeasurementCreator (org.orekit.estimation.measurements.TurnAroundRangeMeasurementCreator)5 Vector3D (org.hipparchus.geometry.euclidean.threed.Vector3D)4 GeodeticPoint (org.orekit.bodies.GeodeticPoint)4 AngularRadioRefractionModifier (org.orekit.estimation.measurements.modifiers.AngularRadioRefractionModifier)4 RangeTroposphericDelayModifier (org.orekit.estimation.measurements.modifiers.RangeTroposphericDelayModifier)4 EarthITU453AtmosphereRefraction (org.orekit.models.earth.EarthITU453AtmosphereRefraction)4 HashMap (java.util.HashMap)3