Examples with RangeTroposphericDelayModifier org.orekit.estimation.measurements.modifiers.RangeTroposphericDelayModifier used on opensource projects

Example 1 with RangeTroposphericDelayModifier

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

the class KalmanOrbitDeterminationTest 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;
}

Example 2 with RangeTroposphericDelayModifier

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

the class RangeAnalyticTest method genericTestStateDerivatives.

/**
 * Generic test function for derivatives with respect to state
 * @param isModifier Use of atmospheric modifiers
 * @param isFiniteDifferences Finite differences reference calculation if true, Range class otherwise
 * @param printResults Print the results ?
 * @throws OrekitException
 */
void genericTestStateDerivatives(final boolean isModifier, final boolean isFiniteDifferences, final boolean printResults, final double refErrorsPMedian, final double refErrorsPMean, final double refErrorsPMax, final double refErrorsVMedian, final double refErrorsVMean, final double refErrorsVMax) 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
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
    // Lists for results' storage - Used only for derivatives with respect to state
    // "final" value to be seen by "handleStep" function of the propagator
    final List<Double> errorsP = new ArrayList<Double>();
    final List<Double> errorsV = new ArrayList<Double>();
    // Set master mode
    // Use a lambda function to implement "handleStep" function
    propagator.setMasterMode((OrekitStepInterpolator interpolator, boolean isLast) -> {
        for (final ObservedMeasurement<?> measurement : measurements) {
            // Play test if the measurement date is between interpolator previous and current date
            if ((measurement.getDate().durationFrom(interpolator.getPreviousState().getDate()) > 0.) && (measurement.getDate().durationFrom(interpolator.getCurrentState().getDate()) <= 0.)) {
                // Add modifiers if test implies it
                final RangeTroposphericDelayModifier modifier = new RangeTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
                if (isModifier) {
                    ((Range) measurement).addModifier(modifier);
                }
                // We intentionally propagate to a date which is close to the
                // real spacecraft state but is *not* the accurate date, by
                // compensating only part of the downlink delay. This is done
                // in order to validate the partial derivatives with respect
                // to velocity. If we had chosen the proper state date, the
                // range would have depended only on the current position but
                // not on the current velocity.
                final double meanDelay = measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
                final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
                final SpacecraftState state = interpolator.getInterpolatedState(date);
                final EstimatedMeasurement<Range> range = new RangeAnalytic((Range) measurement).theoreticalEvaluationAnalytic(0, 0, state);
                if (isModifier) {
                    modifier.modify(range);
                }
                final double[][] jacobian = range.getStateDerivatives(0);
                // Jacobian reference value
                final double[][] jacobianRef;
                if (isFiniteDifferences) {
                    // Compute a reference value using finite differences
                    jacobianRef = Differentiation.differentiate(new StateFunction() {

                        public double[] value(final SpacecraftState state) throws OrekitException {
                            return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
                        }
                    }, measurement.getDimension(), propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 2.0, 3).value(state);
                } else {
                    // Compute a reference value using Range class function
                    jacobianRef = ((Range) measurement).theoreticalEvaluation(0, 0, new SpacecraftState[] { state }).getStateDerivatives(0);
                }
                // //Test: Test point by point with the debugger
                // if (!isFiniteDifferences && !isModifier) {
                // final EstimatedMeasurement<Range> test =
                // new RangeAnalytic((Range)measurement).theoreticalEvaluationValidation(0, 0, state);
                // }
                // //Test
                Assert.assertEquals(jacobianRef.length, jacobian.length);
                Assert.assertEquals(jacobianRef[0].length, jacobian[0].length);
                // Errors & relative errors on the jacobian
                double[][] dJacobian = new double[jacobian.length][jacobian[0].length];
                double[][] dJacobianRelative = new double[jacobian.length][jacobian[0].length];
                for (int i = 0; i < jacobian.length; ++i) {
                    for (int j = 0; j < jacobian[i].length; ++j) {
                        dJacobian[i][j] = jacobian[i][j] - jacobianRef[i][j];
                        dJacobianRelative[i][j] = FastMath.abs(dJacobian[i][j] / jacobianRef[i][j]);
                        if (j < 3) {
                            errorsP.add(dJacobianRelative[i][j]);
                        } else {
                            errorsV.add(dJacobianRelative[i][j]);
                        }
                    }
                }
                // Print values in console ?
                if (printResults) {
                    String stationName = ((Range) measurement).getStation().getBaseFrame().getName();
                    System.out.format(Locale.US, "%-15s  %-23s  %-23s  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e  " + "%10.3e  %10.3e  %10.3e%n", stationName, measurement.getDate(), date, dJacobian[0][0], dJacobian[0][1], dJacobian[0][2], dJacobian[0][3], dJacobian[0][4], dJacobian[0][5], dJacobianRelative[0][0], dJacobianRelative[0][1], dJacobianRelative[0][2], dJacobianRelative[0][3], dJacobianRelative[0][4], dJacobianRelative[0][5]);
                }
            }
        // End if measurement date between previous and current interpolator step
        }
    // End for loop on the measurements
    });
    // Print results on console ?
    if (printResults) {
        System.out.format(Locale.US, "%-15s  %-23s  %-23s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s%n", "Station", "Measurement Date", "State Date", "ΔdPx", "ΔdPy", "ΔdPz", "ΔdVx", "ΔdVy", "ΔdVz", "rel ΔdPx", "rel ΔdPy", "rel ΔdPz", "rel ΔdVx", "rel ΔdVy", "rel ΔdVz");
    }
    // Rewind the propagator to initial date
    propagator.propagate(context.initialOrbit.getDate());
    // Sort measurements chronologically
    measurements.sort(new ChronologicalComparator());
    // Propagate to final measurement's date
    propagator.propagate(measurements.get(measurements.size() - 1).getDate());
    // Convert lists to double[] and evaluate some statistics
    final double[] relErrorsP = errorsP.stream().mapToDouble(Double::doubleValue).toArray();
    final double[] relErrorsV = errorsV.stream().mapToDouble(Double::doubleValue).toArray();
    final double errorsPMedian = new Median().evaluate(relErrorsP);
    final double errorsPMean = new Mean().evaluate(relErrorsP);
    final double errorsPMax = new Max().evaluate(relErrorsP);
    final double errorsVMedian = new Median().evaluate(relErrorsV);
    final double errorsVMean = new Mean().evaluate(relErrorsV);
    final double errorsVMax = new Max().evaluate(relErrorsV);
    // Print the results on console ?
    if (printResults) {
        System.out.println();
        System.out.format(Locale.US, "Relative errors dR/dP -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", errorsPMedian, errorsPMean, errorsPMax);
        System.out.format(Locale.US, "Relative errors dR/dV -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", errorsVMedian, errorsVMean, errorsVMax);
    }
    // Reference comparison with Range class
    Assert.assertEquals(0.0, errorsPMedian, refErrorsPMedian);
    Assert.assertEquals(0.0, errorsPMean, refErrorsPMean);
    Assert.assertEquals(0.0, errorsPMax, refErrorsPMax);
    Assert.assertEquals(0.0, errorsVMedian, refErrorsVMedian);
    Assert.assertEquals(0.0, errorsVMean, refErrorsVMean);
    Assert.assertEquals(0.0, errorsVMax, refErrorsVMax);
}

Example 3 with RangeTroposphericDelayModifier

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

the class RangeAnalyticTest method genericTestParameterDerivatives.

/**
 * Generic test function for derivatives with respect to parameters (station's position in station's topocentric frame)
 * @param isModifier Use of atmospheric modifiers
 * @param isFiniteDifferences Finite differences reference calculation if true, Range class otherwise
 * @param printResults Print the results ?
 * @throws OrekitException
 */
void genericTestParameterDerivatives(final boolean isModifier, final boolean isFiniteDifferences, final boolean printResults) 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);
    // List to store the results
    final List<Double> relErrorList = new ArrayList<Double>();
    // Set master mode
    // Use a lambda function to implement "handleStep" function
    propagator.setMasterMode((OrekitStepInterpolator interpolator, boolean isLast) -> {
        for (final ObservedMeasurement<?> measurement : measurements) {
            // Play test if the measurement date is between interpolator previous and current date
            if ((measurement.getDate().durationFrom(interpolator.getPreviousState().getDate()) > 0.) && (measurement.getDate().durationFrom(interpolator.getCurrentState().getDate()) <= 0.)) {
                // Add modifiers if test implies it
                final RangeTroposphericDelayModifier modifier = new RangeTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
                if (isModifier) {
                    ((Range) measurement).addModifier(modifier);
                }
                // Parameter corresponding to station position offset
                final GroundStation stationParameter = ((Range) measurement).getStation();
                // We intentionally propagate to a date which is close to the
                // real spacecraft state but is *not* the accurate date, by
                // compensating only part of the downlink delay. This is done
                // in order to validate the partial derivatives with respect
                // to velocity. If we had chosen the proper state date, the
                // range would have depended only on the current position but
                // not on the current velocity.
                final double meanDelay = measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
                final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
                final SpacecraftState state = interpolator.getInterpolatedState(date);
                final ParameterDriver[] drivers = new ParameterDriver[] { stationParameter.getEastOffsetDriver(), stationParameter.getNorthOffsetDriver(), stationParameter.getZenithOffsetDriver() };
                if (printResults) {
                    String stationName = ((Range) measurement).getStation().getBaseFrame().getName();
                    System.out.format(Locale.US, "%-15s  %-23s  %-23s  ", stationName, measurement.getDate(), date);
                }
                for (int i = 0; i < 3; ++i) {
                    final double[] gradient = measurement.estimate(0, 0, new SpacecraftState[] { state }).getParameterDerivatives(drivers[i]);
                    Assert.assertEquals(1, measurement.getDimension());
                    Assert.assertEquals(1, gradient.length);
                    // Compute a reference value using analytical formulas
                    final EstimatedMeasurement<Range> rangeAnalytic = new RangeAnalytic((Range) measurement).theoreticalEvaluationAnalytic(0, 0, state);
                    if (isModifier) {
                        modifier.modify(rangeAnalytic);
                    }
                    final double ref = rangeAnalytic.getParameterDerivatives(drivers[i])[0];
                    if (printResults) {
                        System.out.format(Locale.US, "%10.3e  %10.3e  ", gradient[0] - ref, FastMath.abs((gradient[0] - ref) / ref));
                    }
                    final double relError = FastMath.abs((ref - gradient[0]) / ref);
                    relErrorList.add(relError);
                // Assert.assertEquals(ref, gradient[0], 6.1e-5 * FastMath.abs(ref));
                }
                if (printResults) {
                    System.out.format(Locale.US, "%n");
                }
            }
        // End if measurement date between previous and current interpolator step
        }
    // End for loop on the measurements
    });
    // Rewind the propagator to initial date
    propagator.propagate(context.initialOrbit.getDate());
    // Sort measurements chronologically
    measurements.sort(new ChronologicalComparator());
    // Print results ? Header
    if (printResults) {
        System.out.format(Locale.US, "%-15s  %-23s  %-23s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s%n", "Station", "Measurement Date", "State Date", "ΔdQx", "rel ΔdQx", "ΔdQy", "rel ΔdQy", "ΔdQz", "rel ΔdQz");
    }
    // Propagate to final measurement's date
    propagator.propagate(measurements.get(measurements.size() - 1).getDate());
    // Convert error list to double[]
    final double[] relErrors = relErrorList.stream().mapToDouble(Double::doubleValue).toArray();
    // Compute statistics
    final double relErrorsMedian = new Median().evaluate(relErrors);
    final double relErrorsMean = new Mean().evaluate(relErrors);
    final double relErrorsMax = new Max().evaluate(relErrors);
    // Print the results on console ?
    if (printResults) {
        System.out.println();
        System.out.format(Locale.US, "Relative errors dR/dQ -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", relErrorsMedian, relErrorsMean, relErrorsMax);
    }
    // Assert the results / max values depend on the test
    double refErrorsMedian, refErrorsMean, refErrorsMax;
    // Analytic references
    refErrorsMedian = 1.55e-06;
    refErrorsMean = 3.64e-06;
    refErrorsMax = 6.1e-05;
    Assert.assertEquals(0.0, relErrorsMedian, refErrorsMedian);
    Assert.assertEquals(0.0, relErrorsMean, refErrorsMean);
    Assert.assertEquals(0.0, relErrorsMax, refErrorsMax);
}

Example 4 with RangeTroposphericDelayModifier

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

the class RangeTest method genericTestParameterDerivatives.

void genericTestParameterDerivatives(final boolean isModifier, final boolean printResults, final double refErrorsMedian, final double refErrorsMean, final double refErrorsMax) 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);
    // List to store the results
    final List<Double> relErrorList = new ArrayList<Double>();
    // Set master mode
    // Use a lambda function to implement "handleStep" function
    propagator.setMasterMode((OrekitStepInterpolator interpolator, boolean isLast) -> {
        for (final ObservedMeasurement<?> measurement : measurements) {
            // Play test if the measurement date is between interpolator previous and current date
            if ((measurement.getDate().durationFrom(interpolator.getPreviousState().getDate()) > 0.) && (measurement.getDate().durationFrom(interpolator.getCurrentState().getDate()) <= 0.)) {
                // Add modifiers if test implies it
                final RangeTroposphericDelayModifier modifier = new RangeTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
                if (isModifier) {
                    ((Range) measurement).addModifier(modifier);
                }
                // Parameter corresponding to station position offset
                final GroundStation stationParameter = ((Range) measurement).getStation();
                // We intentionally propagate to a date which is close to the
                // real spacecraft state but is *not* the accurate date, by
                // compensating only part of the downlink delay. This is done
                // in order to validate the partial derivatives with respect
                // to velocity. If we had chosen the proper state date, the
                // range would have depended only on the current position but
                // not on the current velocity.
                final double meanDelay = measurement.getObservedValue()[0] / Constants.SPEED_OF_LIGHT;
                final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
                final SpacecraftState state = interpolator.getInterpolatedState(date);
                final ParameterDriver[] drivers = new ParameterDriver[] { stationParameter.getEastOffsetDriver(), stationParameter.getNorthOffsetDriver(), stationParameter.getZenithOffsetDriver() };
                if (printResults) {
                    String stationName = ((Range) measurement).getStation().getBaseFrame().getName();
                    System.out.format(Locale.US, "%-15s  %-23s  %-23s  ", stationName, measurement.getDate(), date);
                }
                for (int i = 0; i < 3; ++i) {
                    final double[] gradient = measurement.estimate(0, 0, new SpacecraftState[] { state }).getParameterDerivatives(drivers[i]);
                    Assert.assertEquals(1, measurement.getDimension());
                    Assert.assertEquals(1, gradient.length);
                    // Compute a reference value using finite differences
                    final ParameterFunction dMkdP = Differentiation.differentiate(new ParameterFunction() {

                        /**
                         * {@inheritDoc}
                         */
                        @Override
                        public double value(final ParameterDriver parameterDriver) throws OrekitException {
                            return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue()[0];
                        }
                    }, drivers[i], 3, 20.0);
                    final double ref = dMkdP.value(drivers[i]);
                    if (printResults) {
                        System.out.format(Locale.US, "%10.3e  %10.3e  ", gradient[0] - ref, FastMath.abs((gradient[0] - ref) / ref));
                    }
                    final double relError = FastMath.abs((ref - gradient[0]) / ref);
                    relErrorList.add(relError);
                // Assert.assertEquals(ref, gradient[0], 6.1e-5 * FastMath.abs(ref));
                }
                if (printResults) {
                    System.out.format(Locale.US, "%n");
                }
            }
        // End if measurement date between previous and current interpolator step
        }
    // End for loop on the measurements
    });
    // Rewind the propagator to initial date
    propagator.propagate(context.initialOrbit.getDate());
    // Sort measurements chronologically
    measurements.sort(new ChronologicalComparator());
    // Print results ? Header
    if (printResults) {
        System.out.format(Locale.US, "%-15s  %-23s  %-23s  " + "%10s  %10s  %10s  " + "%10s  %10s  %10s%n", "Station", "Measurement Date", "State Date", "ΔdQx", "rel ΔdQx", "ΔdQy", "rel ΔdQy", "ΔdQz", "rel ΔdQz");
    }
    // Propagate to final measurement's date
    propagator.propagate(measurements.get(measurements.size() - 1).getDate());
    // Convert error list to double[]
    final double[] relErrors = relErrorList.stream().mapToDouble(Double::doubleValue).toArray();
    // Compute statistics
    final double relErrorsMedian = new Median().evaluate(relErrors);
    final double relErrorsMean = new Mean().evaluate(relErrors);
    final double relErrorsMax = new Max().evaluate(relErrors);
    // Print the results on console ?
    if (printResults) {
        System.out.println();
        System.out.format(Locale.US, "Relative errors dR/dQ -> Median: %6.3e / Mean: %6.3e / Max: %6.3e%n", relErrorsMedian, relErrorsMean, relErrorsMax);
    }
    Assert.assertEquals(0.0, relErrorsMedian, refErrorsMedian);
    Assert.assertEquals(0.0, relErrorsMean, refErrorsMean);
    Assert.assertEquals(0.0, relErrorsMax, refErrorsMax);
}

Example 5 with RangeTroposphericDelayModifier

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

the class OrbitDetermination 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;
}