Package org.orekit.estimation.measurements

Class TurnAroundRange

java.lang.Object

org.orekit.estimation.measurements.AbstractMeasurement<T>

org.orekit.estimation.measurements.GroundReceiverMeasurement<TurnAroundRange>

org.orekit.estimation.measurements.TurnAroundRange

All Implemented Interfaces:

Comparable<ComparableMeasurement>, ComparableMeasurement, ObservedMeasurement<TurnAroundRange>, TimeStamped, ParameterDriversProvider

public class TurnAroundRange
extends GroundReceiverMeasurement<TurnAroundRange>

Class modeling a turn-around range measurement using a primary ground station and a secondary ground station.

The measurement is considered to be a signal: - Emitted from the primary ground station - Reflected on the spacecraft - Reflected on the secondary ground station - Reflected on the spacecraft again - Received on the primary ground station Its value is the elapsed time between emission and reception divided by 2c were c is the speed of light. The motion of the stations and the spacecraft during the signal flight time are taken into account. The date of the measurement corresponds to the reception on ground of the reflected signal.

Since:

9.0

Author:

Thierry Ceolin, Luc Maisonobe, Maxime Journot

Field Summary

Fields

Modifier and Type	Field	Description
static String	MEASUREMENT_TYPE	Type of the measurement.

Constructor Summary

Constructors

Constructor	Description
TurnAroundRange(GroundStation primaryStation, GroundStation secondaryStation, AbsoluteDate date, double turnAroundRange, double sigma, double baseWeight, ObservableSatellite satellite)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
GroundStation	getPrimaryStation()	Get the primary ground station from which measurement is performed.
GroundStation	getSecondaryStation()	Get the secondary ground station reflecting the signal.
protected EstimatedMeasurement<TurnAroundRange>	theoreticalEvaluation(int iteration, int evaluation, SpacecraftState[] states)	Estimate the theoretical value.
protected EstimatedMeasurementBase<TurnAroundRange>	theoreticalEvaluationWithoutDerivatives(int iteration, int evaluation, SpacecraftState[] states)	Estimate the theoretical value without derivatives.

Methods inherited from class org.orekit.estimation.measurements.GroundReceiverMeasurement

computeCommonParametersWithDerivatives, computeCommonParametersWithout, getGroundStationCoordinates, getGroundStationPosition, getStation, isTwoWay

Methods inherited from class org.orekit.estimation.measurements.AbstractMeasurement

addModifier, addParameterDriver, estimate, estimateWithoutDerivatives, getBaseWeight, getCoordinates, getDate, getDimension, getModifiers, getObservedValue, getParametersDrivers, getSatellites, getTheoreticalStandardDeviation, isEnabled, setEnabled, setObservedValue, signalTimeOfFlightAdjustableEmitter, signalTimeOfFlightAdjustableEmitter, signalTimeOfFlightAdjustableEmitter, signalTimeOfFlightAdjustableEmitter, signalTimeOfFlightAdjustableReceiver, signalTimeOfFlightAdjustableReceiver, signalTimeOfFlightAdjustableReceiver, signalTimeOfFlightAdjustableReceiver

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.orekit.estimation.measurements.ComparableMeasurement

compareTo

Methods inherited from interface org.orekit.estimation.measurements.ObservedMeasurement

estimateWithoutDerivatives, getMeasurementType

Methods inherited from interface org.orekit.utils.ParameterDriversProvider

getNbParametersDriversValue, getParameterDriver, getParameters, getParameters, getParameters, getParameters, getParametersAllValues, getParametersAllValues, isSupported

Methods inherited from interface org.orekit.time.TimeStamped

durationFrom

Field Detail

MEASUREMENT_TYPE

public static final String MEASUREMENT_TYPE

Type of the measurement.

See Also:

Constant Field Values

Constructor Detail

TurnAroundRange

public TurnAroundRange(GroundStation primaryStation,
                       GroundStation secondaryStation,
                       AbsoluteDate date,
                       double turnAroundRange,
                       double sigma,
                       double baseWeight,
                       ObservableSatellite satellite)

Simple constructor.

Parameters:

primaryStation - ground station from which measurement is performed

secondaryStation - ground station reflecting the signal

date - date of the measurement

turnAroundRange - observed value

sigma - theoretical standard deviation

baseWeight - base weight

satellite - satellite related to this measurement

Since:

9.3

Method Detail

getPrimaryStation

public GroundStation getPrimaryStation()

Get the primary ground station from which measurement is performed.

Returns:

primary ground station from which measurement is performed

getSecondaryStation

public GroundStation getSecondaryStation()

Get the secondary ground station reflecting the signal.

Returns:

secondary ground station reflecting the signal

theoreticalEvaluationWithoutDerivatives

protected EstimatedMeasurementBase<TurnAroundRange> theoreticalEvaluationWithoutDerivatives(int iteration,
                                                                                            int evaluation,
                                                                                            SpacecraftState[] states)

Estimate the theoretical value without derivatives. The default implementation uses the computation with derivatives and ought to be overwritten for performance.

The theoretical value does not have any modifiers applied.

Overrides:

theoreticalEvaluationWithoutDerivatives in class AbstractMeasurement<TurnAroundRange>

Parameters:

iteration - iteration number

evaluation - evaluation number

states - orbital states at measurement date

Returns:

theoretical value

See Also:

AbstractMeasurement.estimate(int, int, SpacecraftState[])

theoreticalEvaluation

protected EstimatedMeasurement<TurnAroundRange> theoreticalEvaluation(int iteration,
                                                                      int evaluation,
                                                                      SpacecraftState[] states)

Estimate the theoretical value.

The theoretical value does not have any modifiers applied.

Specified by:

theoreticalEvaluation in class AbstractMeasurement<TurnAroundRange>

Parameters:

iteration - iteration number

evaluation - evaluation number

states - orbital states at measurement date

Returns:

theoretical value

See Also:

AbstractMeasurement.estimate(int, int, SpacecraftState[])