Class ModifiedHopfieldModel

  • All Implemented Interfaces:
    TroposphericModel, ParameterDriversProvider

    public class ModifiedHopfieldModel
    extends Object
    implements TroposphericModel
    The modified Hopfield model.

    This model from Hopfield 1969, 1970, 1972 is described in equations 5.105, 5.106, 5.107 and 5.108 in Guochang Xu, GPS - Theory, Algorithms and Applications, Springer, 2007.

    Since:
    12.1
    Author:
    Luc Maisonobe
    See Also:
    "Guochang Xu, GPS - Theory, Algorithms and Applications, Springer, 2007"
    • Constructor Detail

      • ModifiedHopfieldModel

        public ModifiedHopfieldModel()
        Create a new Hopfield model.
    • Method Detail

      • pathDelay

        public TroposphericDelay pathDelay​(TrackingCoordinates trackingCoordinates,
                                           GeodeticPoint point,
                                           PressureTemperatureHumidity weather,
                                           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 TroposphericModel
        Parameters:
        trackingCoordinates - tracking coordinates of the satellite
        point - station location
        weather - weather parameters for constant default values)
        parameters - tropospheric model parameters
        date - current date
        Returns:
        the path delay due to the troposphere
      • pathDelay

        public <T extends CalculusFieldElement<T>> FieldTroposphericDelay<T> pathDelay​(FieldTrackingCoordinates<T> trackingCoordinates,
                                                                                       FieldGeodeticPoint<T> point,
                                                                                       FieldPressureTemperatureHumidity<T> weather,
                                                                                       T[] parameters,
                                                                                       FieldAbsoluteDate<T> date)
        Calculates the tropospheric path delay for the signal path from a ground station to a satellite.

        The Saastamoinen model is not defined for altitudes below 0.0. for continuity reasons, we use the value for h = 0 when altitude is negative.

        There are also numerical issues for elevation angles close to zero. For continuity reasons, elevations lower than a threshold will use the value obtained for the threshold itself.

        Specified by:
        pathDelay in interface TroposphericModel
        Type Parameters:
        T - type of the elements
        Parameters:
        trackingCoordinates - tracking coordinates of the satellite
        point - station location
        weather - weather parameters for constant default values)
        parameters - tropospheric model parameters at current date
        date - current date
        Returns:
        the path delay due to the troposphere