Package org.orekit.estimation.measurements

Class RangeRate

java.lang.Object

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

org.orekit.estimation.measurements.RangeRate

All Implemented Interfaces:

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

public class RangeRate
extends AbstractMeasurement<RangeRate>

Class modeling one-way or two-way range rate measurement between two vehicles. One-way range rate (or Doppler) measurements generally apply to specific satellites (e.g. GNSS, DORIS), where a signal is transmitted from a satellite to a measuring station. Two-way range rate measurements are applicable to any system. The signal is transmitted to the (non-spinning) satellite and returned by a transponder (or reflected back) to the same measuring station. The Doppler measurement can be obtained by multiplying the velocity by (fe/c), where fe is the emission frequency.

Since:

8.0

Author:

Thierry Ceolin, Joris Olympio

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor	Description
RangeRate(GroundStation station, AbsoluteDate date, double rangeRate, double sigma, double baseWeight, boolean twoWay, ObservableSatellite satellite)	Simple constructor.
RangeRate(GroundStation station, AbsoluteDate date, double rangeRate, double sigma, double baseWeight, boolean twoWay, SignalTravelTimeModel signalTravelTimeModel, ObservableSatellite satellite)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
GroundStation	getStation()	Get the ground station that receives the signal.
protected EstimatedMeasurement<RangeRate>	theoreticalEvaluation(int iteration, int evaluation, SpacecraftState[] states)	Estimate the theoretical value.
protected EstimatedMeasurementBase<RangeRate>	theoreticalEvaluationWithoutDerivatives(int iteration, int evaluation, SpacecraftState[] states)	Estimate the theoretical value without derivatives.

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

addModifier, addParameterDriver, addParametersDrivers, estimate, estimateWithoutDerivatives, getBaseWeight, getCoordinates, getDate, getDimension, getModifiers, getObservedValue, getParametersDrivers, getSatellites, getSignalTravelTimeModel, getTheoreticalStandardDeviation, isEnabled, isTwoWay, setEnabled, setObservedValue

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

RangeRate

public RangeRate(GroundStation station,
                 AbsoluteDate date,
                 double rangeRate,
                 double sigma,
                 double baseWeight,
                 boolean twoWay,
                 ObservableSatellite satellite)

Simple constructor.

Parameters:

station - ground station from which measurement is performed

date - date of the measurement

rangeRate - observed value, m/s

sigma - theoretical standard deviation

baseWeight - base weight

twoWay - if true, this is a two-way measurement

satellite - satellite related to this measurement

Since:

9.3

RangeRate

public RangeRate(GroundStation station,
                 AbsoluteDate date,
                 double rangeRate,
                 double sigma,
                 double baseWeight,
                 boolean twoWay,
                 SignalTravelTimeModel signalTravelTimeModel,
                 ObservableSatellite satellite)

Simple constructor.

Parameters:

station - ground station from which measurement is performed

date - date of the measurement

rangeRate - observed value, m/s

sigma - theoretical standard deviation

baseWeight - base weight

twoWay - if true, this is a two-way measurement

signalTravelTimeModel - signal travel model

satellite - satellite related to this measurement

Since:

14.0

Method Detail

getStation

public final GroundStation getStation()

Get the ground station that receives the signal.

Returns:

ground station

theoreticalEvaluationWithoutDerivatives

protected EstimatedMeasurementBase<RangeRate> 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<RangeRate>

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<RangeRate> 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<RangeRate>

Parameters:

iteration - iteration number

evaluation - evaluation number

states - orbital states at measurement date

Returns:

theoretical value

See Also:

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