org.orekit.models.earth.troposphere

Class ViennaThreeModel

java.lang.Object

org.orekit.models.earth.troposphere.ViennaThreeModel

All Implemented Interfaces:

DiscreteTroposphericModel, MappingFunction

public class ViennaThreeModel
extends Object
implements DiscreteTroposphericModel

The Vienna3 tropospheric delay model for radio techniques. The Vienna model data are given with a time interval of 6 hours.

The empirical coefficients b_h, b_w, c_h and c_w are computed with spherical harmonics. In that respect, they are considerably more advanced than those of VMF1 model.

Author:

Bryan Cazabonne

See Also:

"Landskron, D. & Böhm, J. J Geod (2018) VMF3/GPT3: refined discrete and empirical troposphere mapping functions 92: 349. https://doi.org/10.1007/s00190-017-1066-2", "Landskron D (2017) Modeling tropospheric delays for space geodetic techniques. Dissertation, Department of Geodesy and Geoinformation, TU Wien, Supervisor: J. Böhm. http://repositum.tuwien.ac.at/urn:nbn:at:at-ubtuw:1-100249"

Constructor Summary

Constructors

Constructor and Description
ViennaThreeModel(double[] coefficientA, double[] zenithDelay, double latitude, double longitude) Build a new instance.

Method Summary

Modifier and Type	Method and Description
double[]	computeZenithDelay(double height, double[] parameters, AbsoluteDate date) This method allows the computation of the zenith hydrostatic and zenith wet delay.
<T extends RealFieldElement<T>> T[]	computeZenithDelay(T height, T[] parameters, FieldAbsoluteDate<T> date) This method allows the computation of the zenith hydrostatic and zenith wet delay.
List<ParameterDriver>	getParametersDrivers() Get the drivers for tropospheric model parameters.
double[]	mappingFactors(double elevation, double height, double[] parameters, AbsoluteDate date) This method allows the computation of the hydrostatic and wet mapping functions.
<T extends RealFieldElement<T>> T[]	mappingFactors(T elevation, T height, T[] parameters, FieldAbsoluteDate<T> date) This method allows the computation of the hydrostatic and wet mapping functions.
double	pathDelay(double elevation, double height, double[] parameters, AbsoluteDate date) Calculates the tropospheric path delay for the signal path from a ground station to a satellite.
<T extends RealFieldElement<T>> T	pathDelay(T elevation, T height, 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.models.earth.troposphere.MappingFunction

getParameters, getParameters

Constructor Detail

ViennaThreeModel

public ViennaThreeModel(double[] coefficientA,
                        double[] zenithDelay,
                        double latitude,
                        double longitude)

Build a new instance.

Parameters:

coefficientA - The a coefficients for the computation of the wet and hydrostatic mapping functions.

zenithDelay - Values of hydrostatic and wet delays

latitude - geodetic latitude of the station, in radians

longitude - geodetic latitude of the station, in radians

Method Detail

mappingFactors

public double[] mappingFactors(double elevation,
                               double height,
                               double[] parameters,
                               AbsoluteDate date)

This method allows the computation of the hydrostatic and wet mapping functions. The resulting element is an array having the following form:

• double[0] = m_h(e) → hydrostatic mapping function
• double[1] = m_w(e) → wet mapping function

Specified by:

mappingFactors in interface MappingFunction

Parameters:

elevation - the elevation of the satellite, in radians.

height - the height of the station in m above sea level.

parameters - tropospheric model parameters.

date - current date

Returns:

a two components array containing the hydrostatic and wet mapping functions.

mappingFactors

public <T extends RealFieldElement<T>> T[] mappingFactors(T elevation,
                                                          T height,
                                                          T[] parameters,
                                                          FieldAbsoluteDate<T> date)

This method allows the computation of the hydrostatic and wet mapping functions. The resulting element is an array having the following form:

• T[0] = m_h(e) → hydrostatic mapping function
• T[1] = m_w(e) → wet mapping function

Specified by:

mappingFactors in interface MappingFunction

Type Parameters:

T - type of the elements

Parameters:

elevation - the elevation of the satellite, in radians.

height - the height of the station in m above sea level.

parameters - tropospheric model parameters.

date - current date

Returns:

a two components array containing the hydrostatic and wet mapping functions.

pathDelay

public double pathDelay(double elevation,
                        double height,
                        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

height - the height of the station in m above sea level

parameters - tropospheric model parameters.

date - current date

Returns:

the path delay due to the troposphere in m

pathDelay

public <T extends RealFieldElement<T>> T pathDelay(T elevation,
                                                   T height,
                                                   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

height - the height of the station in m above sea level

parameters - tropospheric model parameters.

date - current date

Returns:

the path delay due to the troposphere in m

computeZenithDelay

public double[] computeZenithDelay(double height,
                                   double[] parameters,
                                   AbsoluteDate date)

This method allows the computation of the zenith hydrostatic and zenith wet delay. The resulting element is an array having the following form:

• double[0] = D_hz → zenith hydrostatic delay
• double[1] = D_wz → zenith wet delay

Specified by:

computeZenithDelay in interface DiscreteTroposphericModel

Parameters:

height - the height of the station in m above sea level.

parameters - tropospheric model parameters.

date - current date

Returns:

a two components array containing the zenith hydrostatic and wet delays.

computeZenithDelay

public <T extends RealFieldElement<T>> T[] computeZenithDelay(T height,
                                                              T[] parameters,
                                                              FieldAbsoluteDate<T> date)

This method allows the computation of the zenith hydrostatic and zenith wet delay. The resulting element is an array having the following form:

• T[0] = D_hz → zenith hydrostatic delay
• T[1] = D_wz → zenith wet delay

Specified by:

computeZenithDelay in interface DiscreteTroposphericModel

Type Parameters:

T - type of the elements

Parameters:

height - the height of the station in m above sea level.

parameters - tropospheric model parameters.

date - current date

Returns:

a two components array containing the zenith hydrostatic and wet delays.

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Get the drivers for tropospheric model parameters.

Specified by:

getParametersDrivers in interface MappingFunction

Returns:

drivers for tropospheric model parameters