Examples with AngularAzEl org.orekit.estimation.measurements.AngularAzEl used on opensource projects

Example 6 with AngularAzEl

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

the class OrbitDetermination method readMeasurements.

/**
 * Read a measurements file.
 * @param file measurements file
 * @param stations name to stations data map
 * @param pvData PV measurements data
 * @param satRangeBias range bias due to transponder delay
 * @param weights base weights for measurements
 * @param rangeOutliersManager manager for range measurements outliers (null if none configured)
 * @param rangeRateOutliersManager manager for range-rate measurements outliers (null if none configured)
 * @param azElOutliersManager manager for azimuth-elevation measurements outliers (null if none configured)
 * @param pvOutliersManager manager for PV measurements outliers (null if none configured)
 * @return measurements list
 */
private List<ObservedMeasurement<?>> readMeasurements(final File file, final Map<String, StationData> stations, final PVData pvData, final Bias<Range> satRangeBias, final Weights weights, final OutlierFilter<Range> rangeOutliersManager, final OutlierFilter<RangeRate> rangeRateOutliersManager, final OutlierFilter<AngularAzEl> azElOutliersManager, final OutlierFilter<PV> pvOutliersManager) throws UnsupportedEncodingException, IOException, OrekitException {
    final List<ObservedMeasurement<?>> measurements = new ArrayList<ObservedMeasurement<?>>();
    BufferedReader br = null;
    try {
        br = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8"));
        int lineNumber = 0;
        for (String line = br.readLine(); line != null; line = br.readLine()) {
            ++lineNumber;
            line = line.trim();
            if (line.length() > 0 && !line.startsWith("#")) {
                String[] fields = line.split("\\s+");
                if (fields.length < 2) {
                    throw new OrekitException(OrekitMessages.UNABLE_TO_PARSE_LINE_IN_FILE, lineNumber, file.getName(), line);
                }
                switch(fields[1]) {
                    case "RANGE":
                        final Range range = new RangeParser().parseFields(fields, stations, pvData, satRangeBias, weights, line, lineNumber, file.getName());
                        if (rangeOutliersManager != null) {
                            range.addModifier(rangeOutliersManager);
                        }
                        addIfNonZeroWeight(range, measurements);
                        break;
                    case "RANGE_RATE":
                        final RangeRate rangeRate = new RangeRateParser().parseFields(fields, stations, pvData, satRangeBias, weights, line, lineNumber, file.getName());
                        if (rangeRateOutliersManager != null) {
                            rangeRate.addModifier(rangeRateOutliersManager);
                        }
                        addIfNonZeroWeight(rangeRate, measurements);
                        break;
                    case "AZ_EL":
                        final AngularAzEl angular = new AzElParser().parseFields(fields, stations, pvData, satRangeBias, weights, line, lineNumber, file.getName());
                        if (azElOutliersManager != null) {
                            angular.addModifier(azElOutliersManager);
                        }
                        addIfNonZeroWeight(angular, measurements);
                        break;
                    case "PV":
                        final PV pv = new PVParser().parseFields(fields, stations, pvData, satRangeBias, weights, line, lineNumber, file.getName());
                        if (pvOutliersManager != null) {
                            pv.addModifier(pvOutliersManager);
                        }
                        addIfNonZeroWeight(pv, measurements);
                        break;
                    default:
                        throw new OrekitException(LocalizedCoreFormats.SIMPLE_MESSAGE, "unknown measurement type " + fields[1] + " at line " + lineNumber + " in file " + file.getName());
                }
            }
        }
    } finally {
        if (br != null) {
            br.close();
        }
    }
    if (measurements.isEmpty()) {
        throw new OrekitException(LocalizedCoreFormats.SIMPLE_MESSAGE, "not measurements read from file " + file.getAbsolutePath());
    }
    return measurements;
}

Example 7 with AngularAzEl

use of org.orekit.estimation.measurements.AngularAzEl 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;
}

Example 8 with AngularAzEl

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

the class OrbitDetermination method run.

private void run(final File input, final File home) throws IOException, IllegalArgumentException, OrekitException, ParseException {
    // read input parameters
    KeyValueFileParser<ParameterKey> parser = new KeyValueFileParser<ParameterKey>(ParameterKey.class);
    try (final FileInputStream fis = new FileInputStream(input)) {
        parser.parseInput(input.getAbsolutePath(), fis);
    }
    // log file
    final String baseName;
    final PrintStream logStream;
    if (parser.containsKey(ParameterKey.OUTPUT_BASE_NAME) && parser.getString(ParameterKey.OUTPUT_BASE_NAME).length() > 0) {
        baseName = parser.getString(ParameterKey.OUTPUT_BASE_NAME);
        logStream = new PrintStream(new File(home, baseName + "-log.out"), "UTF-8");
    } else {
        baseName = null;
        logStream = null;
    }
    final RangeLog rangeLog = new RangeLog(home, baseName);
    final RangeRateLog rangeRateLog = new RangeRateLog(home, baseName);
    final AzimuthLog azimuthLog = new AzimuthLog(home, baseName);
    final ElevationLog elevationLog = new ElevationLog(home, baseName);
    final PositionLog positionLog = new PositionLog(home, baseName);
    final VelocityLog velocityLog = new VelocityLog(home, baseName);
    try {
        // gravity field
        final NormalizedSphericalHarmonicsProvider gravityField = createGravityField(parser);
        // Orbit initial guess
        final Orbit initialGuess = createOrbit(parser, gravityField.getMu());
        // IERS conventions
        final IERSConventions conventions;
        if (!parser.containsKey(ParameterKey.IERS_CONVENTIONS)) {
            conventions = IERSConventions.IERS_2010;
        } else {
            conventions = IERSConventions.valueOf("IERS_" + parser.getInt(ParameterKey.IERS_CONVENTIONS));
        }
        // central body
        final OneAxisEllipsoid body = createBody(parser);
        // propagator builder
        final NumericalPropagatorBuilder propagatorBuilder = createPropagatorBuilder(parser, conventions, gravityField, body, initialGuess);
        // estimator
        final BatchLSEstimator estimator = createEstimator(parser, propagatorBuilder);
        // measurements
        final List<ObservedMeasurement<?>> measurements = new ArrayList<ObservedMeasurement<?>>();
        for (final String fileName : parser.getStringsList(ParameterKey.MEASUREMENTS_FILES, ',')) {
            measurements.addAll(readMeasurements(new File(input.getParentFile(), fileName), createStationsData(parser, body), createPVData(parser), createSatRangeBias(parser), createWeights(parser), createRangeOutliersManager(parser), createRangeRateOutliersManager(parser), createAzElOutliersManager(parser), createPVOutliersManager(parser)));
        }
        for (ObservedMeasurement<?> measurement : measurements) {
            estimator.addMeasurement(measurement);
        }
        // estimate orbit
        estimator.setObserver(new BatchLSObserver() {

            private PVCoordinates previousPV;

            {
                previousPV = initialGuess.getPVCoordinates();
                final String header = "iteration evaluations      ΔP(m)        ΔV(m/s)           RMS          nb Range    nb Range-rate  nb Angular     nb PV%n";
                System.out.format(Locale.US, header);
                if (logStream != null) {
                    logStream.format(Locale.US, header);
                }
            }

            /**
             * {@inheritDoc}
             */
            @Override
            public void evaluationPerformed(final int iterationsCount, final int evaluationsCount, final Orbit[] orbits, final ParameterDriversList estimatedOrbitalParameters, final ParameterDriversList estimatedPropagatorParameters, final ParameterDriversList estimatedMeasurementsParameters, final EstimationsProvider evaluationsProvider, final LeastSquaresProblem.Evaluation lspEvaluation) {
                PVCoordinates currentPV = orbits[0].getPVCoordinates();
                final String format0 = "    %2d         %2d                                 %16.12f     %s       %s     %s     %s%n";
                final String format = "    %2d         %2d      %13.6f %12.9f %16.12f     %s       %s     %s     %s%n";
                final EvaluationCounter<Range> rangeCounter = new EvaluationCounter<Range>();
                final EvaluationCounter<RangeRate> rangeRateCounter = new EvaluationCounter<RangeRate>();
                final EvaluationCounter<AngularAzEl> angularCounter = new EvaluationCounter<AngularAzEl>();
                final EvaluationCounter<PV> pvCounter = new EvaluationCounter<PV>();
                for (final Map.Entry<ObservedMeasurement<?>, EstimatedMeasurement<?>> entry : estimator.getLastEstimations().entrySet()) {
                    if (entry.getKey() instanceof Range) {
                        @SuppressWarnings("unchecked") EstimatedMeasurement<Range> evaluation = (EstimatedMeasurement<Range>) entry.getValue();
                        rangeCounter.add(evaluation);
                    } else if (entry.getKey() instanceof RangeRate) {
                        @SuppressWarnings("unchecked") EstimatedMeasurement<RangeRate> evaluation = (EstimatedMeasurement<RangeRate>) entry.getValue();
                        rangeRateCounter.add(evaluation);
                    } else if (entry.getKey() instanceof AngularAzEl) {
                        @SuppressWarnings("unchecked") EstimatedMeasurement<AngularAzEl> evaluation = (EstimatedMeasurement<AngularAzEl>) entry.getValue();
                        angularCounter.add(evaluation);
                    } else if (entry.getKey() instanceof PV) {
                        @SuppressWarnings("unchecked") EstimatedMeasurement<PV> evaluation = (EstimatedMeasurement<PV>) entry.getValue();
                        pvCounter.add(evaluation);
                    }
                }
                if (evaluationsCount == 1) {
                    System.out.format(Locale.US, format0, iterationsCount, evaluationsCount, lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
                    if (logStream != null) {
                        logStream.format(Locale.US, format0, iterationsCount, evaluationsCount, lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
                    }
                } else {
                    System.out.format(Locale.US, format, iterationsCount, evaluationsCount, Vector3D.distance(previousPV.getPosition(), currentPV.getPosition()), Vector3D.distance(previousPV.getVelocity(), currentPV.getVelocity()), lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
                    if (logStream != null) {
                        logStream.format(Locale.US, format, iterationsCount, evaluationsCount, Vector3D.distance(previousPV.getPosition(), currentPV.getPosition()), Vector3D.distance(previousPV.getVelocity(), currentPV.getVelocity()), lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
                    }
                }
                previousPV = currentPV;
            }
        });
        Orbit estimated = estimator.estimate()[0].getInitialState().getOrbit();
        // compute some statistics
        for (final Map.Entry<ObservedMeasurement<?>, EstimatedMeasurement<?>> entry : estimator.getLastEstimations().entrySet()) {
            if (entry.getKey() instanceof Range) {
                @SuppressWarnings("unchecked") EstimatedMeasurement<Range> evaluation = (EstimatedMeasurement<Range>) entry.getValue();
                rangeLog.add(evaluation);
            } else if (entry.getKey() instanceof RangeRate) {
                @SuppressWarnings("unchecked") EstimatedMeasurement<RangeRate> evaluation = (EstimatedMeasurement<RangeRate>) entry.getValue();
                rangeRateLog.add(evaluation);
            } else if (entry.getKey() instanceof AngularAzEl) {
                @SuppressWarnings("unchecked") EstimatedMeasurement<AngularAzEl> evaluation = (EstimatedMeasurement<AngularAzEl>) entry.getValue();
                azimuthLog.add(evaluation);
                elevationLog.add(evaluation);
            } else if (entry.getKey() instanceof PV) {
                @SuppressWarnings("unchecked") EstimatedMeasurement<PV> evaluation = (EstimatedMeasurement<PV>) entry.getValue();
                positionLog.add(evaluation);
                velocityLog.add(evaluation);
            }
        }
        System.out.println("Estimated orbit: " + estimated);
        if (logStream != null) {
            logStream.println("Estimated orbit: " + estimated);
        }
        final ParameterDriversList orbitalParameters = estimator.getOrbitalParametersDrivers(true);
        final ParameterDriversList propagatorParameters = estimator.getPropagatorParametersDrivers(true);
        final ParameterDriversList measurementsParameters = estimator.getMeasurementsParametersDrivers(true);
        int length = 0;
        for (final ParameterDriver parameterDriver : orbitalParameters.getDrivers()) {
            length = FastMath.max(length, parameterDriver.getName().length());
        }
        for (final ParameterDriver parameterDriver : propagatorParameters.getDrivers()) {
            length = FastMath.max(length, parameterDriver.getName().length());
        }
        for (final ParameterDriver parameterDriver : measurementsParameters.getDrivers()) {
            length = FastMath.max(length, parameterDriver.getName().length());
        }
        displayParametersChanges(System.out, "Estimated orbital parameters changes: ", false, length, orbitalParameters);
        if (logStream != null) {
            displayParametersChanges(logStream, "Estimated orbital parameters changes: ", false, length, orbitalParameters);
        }
        displayParametersChanges(System.out, "Estimated propagator parameters changes: ", true, length, propagatorParameters);
        if (logStream != null) {
            displayParametersChanges(logStream, "Estimated propagator parameters changes: ", true, length, propagatorParameters);
        }
        displayParametersChanges(System.out, "Estimated measurements parameters changes: ", true, length, measurementsParameters);
        if (logStream != null) {
            displayParametersChanges(logStream, "Estimated measurements parameters changes: ", true, length, measurementsParameters);
        }
        System.out.println("Number of iterations: " + estimator.getIterationsCount());
        System.out.println("Number of evaluations: " + estimator.getEvaluationsCount());
        rangeLog.displaySummary(System.out);
        rangeRateLog.displaySummary(System.out);
        azimuthLog.displaySummary(System.out);
        elevationLog.displaySummary(System.out);
        positionLog.displaySummary(System.out);
        velocityLog.displaySummary(System.out);
        if (logStream != null) {
            logStream.println("Number of iterations: " + estimator.getIterationsCount());
            logStream.println("Number of evaluations: " + estimator.getEvaluationsCount());
            rangeLog.displaySummary(logStream);
            rangeRateLog.displaySummary(logStream);
            azimuthLog.displaySummary(logStream);
            elevationLog.displaySummary(logStream);
            positionLog.displaySummary(logStream);
            velocityLog.displaySummary(logStream);
        }
        rangeLog.displayResiduals();
        rangeRateLog.displayResiduals();
        azimuthLog.displayResiduals();
        elevationLog.displayResiduals();
        positionLog.displayResiduals();
        velocityLog.displayResiduals();
    } finally {
        if (logStream != null) {
            logStream.close();
        }
        rangeLog.close();
        rangeRateLog.close();
        azimuthLog.close();
        elevationLog.close();
        positionLog.close();
        velocityLog.close();
    }
}

Example 9 with AngularAzEl

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

the class AngularRadioRefractionModifier method modify.

@Override
public void modify(final EstimatedMeasurement<AngularAzEl> estimated) throws OrekitException {
    final AngularAzEl measure = estimated.getObservedMeasurement();
    final GroundStation station = measure.getStation();
    final SpacecraftState state = estimated.getStates()[0];
    final double correction = angularErrorRadioRefractionModel(station, state);
    // update estimated value taking into account the tropospheric elevation corection.
    // The tropospheric elevation correction is directly added to the elevation.
    final double[] oldValue = estimated.getEstimatedValue();
    final double[] newValue = oldValue.clone();
    // consider only effect on elevation
    newValue[1] = newValue[1] + correction;
    estimated.setEstimatedValue(newValue[0], newValue[1]);
}

Example 10 with AngularAzEl

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

the class AngularIonosphericDelayModifier method modify.

@Override
public void modify(final EstimatedMeasurement<AngularAzEl> estimated) throws OrekitException {
    final AngularAzEl measure = estimated.getObservedMeasurement();
    final GroundStation station = measure.getStation();
    final SpacecraftState state = estimated.getStates()[0];
    final double delay = angularErrorIonosphericModel(station, state);
    // Delay is taken into account to shift the spacecraft position
    final double dt = delay / Constants.SPEED_OF_LIGHT;
    // Position of the spacecraft shifted of dt
    final SpacecraftState transitState = state.shiftedBy(-dt);
    // Update estimated value taking into account the ionospheric delay.
    final AbsoluteDate date = transitState.getDate();
    final Vector3D position = transitState.getPVCoordinates().getPosition();
    final Frame inertial = transitState.getFrame();
    // Elevation and azimuth in radians
    final double elevation = station.getBaseFrame().getElevation(position, inertial, date);
    final double baseAzimuth = station.getBaseFrame().getAzimuth(position, inertial, date);
    final double twoPiWrap = MathUtils.normalizeAngle(baseAzimuth, measure.getObservedValue()[0]) - baseAzimuth;
    final double azimuth = baseAzimuth + twoPiWrap;
    // Update estimated value taking into account the ionospheric delay.
    // Azimuth - elevation values
    estimated.setEstimatedValue(azimuth, elevation);
}