org.orekit.models.earth.ionosphere

Class EstimatedIonosphericModel

java.lang.Object

org.orekit.models.earth.ionosphere.EstimatedIonosphericModel

All Implemented Interfaces:

IonosphericModel, ParameterDriversProvider

public class EstimatedIonosphericModel
extends Object
implements IonosphericModel

An estimated ionospheric model. The ionospheric delay is computed according to the formula:

40.3 δ = -------- * STEC with, STEC = VTEC * F(elevation) f²

With:

• f: The frequency of the signal in Hz.
• STEC: The Slant Total Electron Content in TECUnits.
• VTEC: The Vertical Total Electron Content in TECUnits.
• F(elevation): A mapping function which depends on satellite elevation.

The VTEC is estimated as a ParameterDriver

Since:

10.2

Author:

Bryan Cazabonne

Field Summary

Fields

Modifier and Type	Field and Description
static String	VERTICAL_TOTAL_ELECTRON_CONTENT Name of the parameter of this model: the Vertical Total Electron Content.

Constructor Summary

Constructors

Constructor and Description
EstimatedIonosphericModel(IonosphericMappingFunction model, double vtecValue) Build a new instance.

Method Summary

Modifier and Type	Method and Description
List<ParameterDriver>	getParametersDrivers() Get the drivers for parameters.
double	pathDelay(double elevation, double frequency, double[] parameters) Calculates the ionospheric path delay for the signal path from a ground station to a satellite.
<T extends org.hipparchus.CalculusFieldElement<T>> T	pathDelay(FieldSpacecraftState<T> state, TopocentricFrame baseFrame, double frequency, T[] parameters) Calculates the ionospheric path delay for the signal path from a ground station to a satellite.
double	pathDelay(SpacecraftState state, TopocentricFrame baseFrame, double frequency, double[] parameters) Calculates the ionospheric path delay for the signal path from a ground station to a satellite.
<T extends org.hipparchus.CalculusFieldElement<T>> T	pathDelay(T elevation, double frequency, T[] parameters) Calculates the ionospheric path delay for the signal path from a ground station to a satellite.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.utils.ParameterDriversProvider

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

Field Detail

VERTICAL_TOTAL_ELECTRON_CONTENT

public static final String VERTICAL_TOTAL_ELECTRON_CONTENT

Name of the parameter of this model: the Vertical Total Electron Content.

See Also:

Constant Field Values

Constructor Detail

EstimatedIonosphericModel

public EstimatedIonosphericModel(IonosphericMappingFunction model,
                                 double vtecValue)

Build a new instance.

Parameters:

model - ionospheric mapping function

vtecValue - value of the Vertical Total Electron Content in TECUnits

Method Detail

pathDelay

public double pathDelay(SpacecraftState state,
                        TopocentricFrame baseFrame,
                        double frequency,
                        double[] parameters)

Calculates the ionospheric path delay for the signal path from a ground station to a satellite.

This method is intended to be used for orbit determination issues. In that respect, if the elevation is below 0° the path delay will be equal to zero.

For individual use of the ionospheric model (i.e. not for orbit determination), another method signature can be implemented to compute the path delay for any elevation angle.

Specified by:

pathDelay in interface IonosphericModel

Parameters:

state - spacecraft state

baseFrame - base frame associated with the station

frequency - frequency of the signal in Hz

parameters - ionospheric model parameters at state date

Returns:

the path delay due to the ionosphere in m

pathDelay

public double pathDelay(double elevation,
                        double frequency,
                        double[] parameters)

Calculates the ionospheric path delay for the signal path from a ground station to a satellite.

The path delay is computed for any elevation angle.

Parameters:

elevation - elevation of the satellite in radians

frequency - frequency of the signal in Hz

parameters - ionospheric model parameters

Returns:

the path delay due to the ionosphere in m

pathDelay

public <T extends org.hipparchus.CalculusFieldElement<T>> T pathDelay(FieldSpacecraftState<T> state,
                                                                      TopocentricFrame baseFrame,
                                                                      double frequency,
                                                                      T[] parameters)

Calculates the ionospheric path delay for the signal path from a ground station to a satellite.

This method is intended to be used for orbit determination issues. In that respect, if the elevation is below 0° the path delay will be equal to zero.

For individual use of the ionospheric model (i.e. not for orbit determination), another method signature can be implemented to compute the path delay for any elevation angle.

Specified by:

pathDelay in interface IonosphericModel

Type Parameters:

T - type of the elements

Parameters:

state - spacecraft state

baseFrame - base frame associated with the station

frequency - frequency of the signal in Hz

parameters - ionospheric model parameters at state date

Returns:

the path delay due to the ionosphere in m

pathDelay

public <T extends org.hipparchus.CalculusFieldElement<T>> T pathDelay(T elevation,
                                                                      double frequency,
                                                                      T[] parameters)

Calculates the ionospheric path delay for the signal path from a ground station to a satellite.

The path delay is computed for any elevation angle.

Type Parameters:

T - type of the elements

Parameters:

elevation - elevation of the satellite in radians

frequency - frequency of the signal in Hz

parameters - ionospheric model parameters at state date

Returns:

the path delay due to the ionosphere in m

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Description copied from interface: ParameterDriversProvider

Get the drivers for parameters.

Specified by:

getParametersDrivers in interface ParameterDriversProvider

Returns:

drivers for parameters