Package org.orekit.models.earth.troposphere

Class EstimatedTroposphericModel

java.lang.Object

org.orekit.models.earth.troposphere.EstimatedTroposphericModel

All Implemented Interfaces:

DiscreteTroposphericModel, ParameterDriversProvider

public class EstimatedTroposphericModel
extends Object
implements DiscreteTroposphericModel

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

δ = δ_h * m_h + (δ_t - δ_h) * m_w

With:

• δ_h: Tropospheric zenith hydro-static delay.
• δ_t: Tropospheric total zenith delay.
• m_h: Hydro-static mapping function.
• m_w: Wet mapping function.

The mapping functions m_h(e) and m_w(e) are computed thanks to a model initialized by the user. The user has the possibility to use several mapping function models for the computations: the Global Mapping Function, or the Niell Mapping Function

The tropospheric zenith delay δ_h is computed empirically with a ModifiedSaastamoinenModel while the tropospheric total zenith delay δ_t is estimated as a ParameterDriver

Field Summary

Fields

Modifier and Type	Field	Description
static String	TOTAL_ZENITH_DELAY	Name of the parameter of this model: the total zenith delay.

Constructor Summary

Constructors

Constructor	Description
EstimatedTroposphericModel(double t0, double p0, MappingFunction model, double totalDelay)	Build a new instance using the given environmental conditions.
EstimatedTroposphericModel(MappingFunction model, double totalDelay)	Build a new instance using a standard atmosphere model.

Method Summary

Modifier and Type	Method	Description
List<ParameterDriver>	getParametersDrivers()	Get the drivers for parameters.
double	pathDelay(double elevation, GeodeticPoint point, double[] parameters, AbsoluteDate date)	Calculates the tropospheric path delay for the signal path from a ground station to a satellite.
<T extends CalculusFieldElement<T>> T	pathDelay(T elevation, FieldGeodeticPoint<T> point, T[] parameters, FieldAbsoluteDate<T> date)	Calculates the tropospheric 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

TOTAL_ZENITH_DELAY

public static final String TOTAL_ZENITH_DELAY

Name of the parameter of this model: the total zenith delay.

See Also:

Constant Field Values

Constructor Detail

EstimatedTroposphericModel

public EstimatedTroposphericModel(double t0,
                                  double p0,
                                  MappingFunction model,
                                  double totalDelay)

Build a new instance using the given environmental conditions.

Parameters:

t0 - the temperature at the station [K]

p0 - the atmospheric pressure at the station [mbar]

model - mapping function model (NMF or GMF).

totalDelay - initial value for the tropospheric zenith total delay [m]

EstimatedTroposphericModel

public EstimatedTroposphericModel(MappingFunction model,
                                  double totalDelay)

Build a new instance using a standard atmosphere model.

• temperature: 18 degree Celsius
• pressure: 1013.25 mbar

Parameters:

model - mapping function model (NMF or GMF).

totalDelay - initial value for the tropospheric zenith total delay [m]

Method Detail

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Get the drivers for parameters.

Specified by:

getParametersDrivers in interface ParameterDriversProvider

Returns:

drivers for parameters

pathDelay

public double pathDelay(double elevation,
                        GeodeticPoint point,
                        double[] parameters,
                        AbsoluteDate date)

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

Specified by:

pathDelay in interface DiscreteTroposphericModel

Parameters:

elevation - the elevation of the satellite, in radians

point - station location

parameters - tropospheric model parameters

date - current date

Returns:

the path delay due to the troposphere in m

pathDelay

public <T extends CalculusFieldElement<T>> T pathDelay(T elevation,
                                                       FieldGeodeticPoint<T> point,
                                                       T[] parameters,
                                                       FieldAbsoluteDate<T> date)

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

Specified by:

pathDelay in interface DiscreteTroposphericModel

Type Parameters:

T - type of the elements

Parameters:

elevation - the elevation of the satellite, in radians

point - station location

parameters - tropospheric model parameters at current date

date - current date

Returns:

the path delay due to the troposphere in m