tropmodel.hpp

GPS定位中对流层模型改正

         /// Compute and return the zenith delay for wet component of the troposphere
      virtual double wet_zenith_delay(void) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for dry component
         /// of the troposphere
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double dry_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for wet component
         /// of the troposphere
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double wet_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Re-define the tropospheric model with explicit weather data.
         /// Typically called just before correction().
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
      virtual void setWeather(const double& T,
                              const double& P,
                              const double& H)
         throw(InvalidParameter);

         /// Re-define the tropospheric model with explicit weather data.
         /// Typically called just before correction().
         /// @param wx the weather to use for this correction       
      virtual void setWeather(const WxObservation& wx)
         throw(InvalidParameter);

   private:
      double Cdrydelay;
      double Cwetdelay;
      double Cdrymap;
      double Cwetmap;

   };    // end class SimpleTropModel

   //---------------------------------------------------------------------------------
   /** Tropospheric model based on Goad and Goodman(1974),
    *  "A Modified Hopfield Tropospheric Refraction Correction Model," Paper
    * presented at the Fall Annual Meeting of the American Geophysical Union,
    * San Francisco, December 1974, as presented in Leick, "GPS Satellite Surveying,"
    * Wiley, NY, 1990, Chapter 9 (note particularly Table 9.1).
    */
   class GGTropModel : public TropModel
   {
   public:
         /// Empty constructor
      GGTropModel(void);

         /// Creates a trop model, with weather observation input
         /// @param wx the weather to use for this correction.
      GGTropModel(const WxObservation& wx)
         throw(InvalidParameter);

         /// Create a tropospheric model from explicit weather data
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
      GGTropModel(const double& T,
                  const double& P,
                  const double& H)
         throw(InvalidParameter);

         /// Compute and return the zenith delay for dry component
         /// of the troposphere
      virtual double dry_zenith_delay(void) const
         throw(InvalidTropModel);

         /// Compute and return the zenith delay for wet component
         /// of the troposphere
      virtual double wet_zenith_delay(void) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for dry component
         /// of the troposphere
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double dry_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for wet component
         /// of the troposphere
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double wet_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Re-define the tropospheric model with explicit weather data.
         /// Typically called initially, and whenever the weather changes.
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
      virtual void setWeather(const double& T,
                              const double& P,
                              const double& H)
         throw(InvalidParameter);

         /// Re-define the tropospheric model with explicit weather data.
         /// Typically called just before correction().
         /// @param wx the weather to use for this correction       
      virtual void setWeather(const WxObservation& wx)
         throw(InvalidParameter);

   private:
      double Cdrydelay;
      double Cwetdelay;
      double Cdrymap;
      double Cwetmap;

   };    // end class GGTropModel

   //---------------------------------------------------------------------------------
   /** Tropospheric model with heights based on Goad and Goodman(1974),
    *  "A Modified Hopfield Tropospheric Refraction Correction Model," Paper
    *  presented at the Fall Annual Meeting of the American Geophysical Union,
    *  San Francisco, December 1974.
    *
    *  (Not the same as GGTropModel because this has height dependence, and the
    *  computation of this model does not break cleanly into wet and dry components.)
    *
    *  NB this model requires heights, both of the weather parameters,
    *    and of the receiver.
    *  Thus, usually, caller will set heights at the same time the weather is set:
    *
    * @code
    *    GGHeightTropModel ggh;
    *    ggh.setWeather(T,P,H);
    *    ggh.setHeights(hT,hP,hH);
    * @endcode
    *
    *  and when the correction (and/or delay and map) is computed,
    *  receiver height is set before the call to correction(elevation):
    *
    * @code
    *    ggh.setReceiverHeight(height);
    *    trop = ggh.correction(elevation);
    * @endcode
    *
    *  NB setReceiverHeight(ht) sets the 'weather heights' as well, if they are not
    *    already defined.
    */
   class GGHeightTropModel : public TropModel
   {
   public:
         /// Empty constructor
      GGHeightTropModel(void);

         /// Creates a trop model, with weather observation input
         /// @param wx the weather to use for this correction.
      GGHeightTropModel(const WxObservation& wx)
         throw(InvalidParameter);

         /// Create a tropospheric model from explicit weather data
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
      GGHeightTropModel(const double& T,
                        const double& P,
                        const double& H)
         throw(InvalidParameter);

         /// Create a valid model from explicit input.
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
         /// @param hT height at which temperature applies in meters.
         /// @param hP height at which atmospheric pressure applies in meters.
         /// @param hH height at which relative humidity applies in meters.
      GGHeightTropModel(const double& T,
                        const double& P,
                        const double& H,
                        const double hT,
                        const double hP,
                        const double hH)
         throw(InvalidParameter);

         /// Compute and return the full tropospheric delay
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double correction(double elevation) const
         throw(InvalidTropModel);

         /**
          * Compute and return the full tropospheric delay, given the positions of
          * receiver and satellite and the time tag. This version is most useful
          * within positioning algorithms, where the receiver position and timetag
          * may vary; it computes the elevation (and other receiver location
          * information) and passes them to appropriate set...() routines and the
          * correction(elevation) routine.
          * @param RX  Receiver position
          * @param SV  Satellite position
          * @param tt  Time tag of the signal 
          */
      virtual double correction(const Position& RX,
                                const Position& SV,
                                const DayTime& tt)
         throw(InvalidTropModel);

         /** \deprecated
          * Compute and return the full tropospheric delay, given the positions of
          * receiver and satellite and the time tag. This version is most useful
          * within positioning algorithms, where the receiver position and timetag
          * may vary; it computes the elevation (and other receiver location
          * information) and passes them to appropriate set...() routines and the
          * correction(elevation) routine.
          * @param RX  Receiver position in ECEF cartesian coordinates (meters)
          * @param SV  Satellite position in ECEF cartesian coordinates (meters)
          * @param tt  Time tag of the signal 
          */
      virtual double correction(const Xvt& RX,
                                const Xvt& SV,
                                const DayTime& tt)
         throw(InvalidTropModel);

         /// Compute and return the zenith delay for dry component
         /// of the troposphere
      virtual double dry_zenith_delay(void) const
         throw(InvalidTropModel);

         /// Compute and return the zenith delay for wet component of the troposphere
      virtual double wet_zenith_delay(void) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for dry component of
         /// the troposphere.
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double dry_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Compute and return the mapping function for wet component of
         /// the troposphere.
         /// @param elevation Elevation of satellite as seen at receiver, in degrees
      virtual double wet_mapping_function(double elevation) const
         throw(InvalidTropModel);

         /// Re-define the weather data.
         /// Typically called initially, and whenever the weather changes.
         /// @param T temperature in degrees Celsius
         /// @param P atmospheric pressure in millibars
         /// @param H relative humidity in percent
      virtual void setWeather(const double& T,
                              const double& P,
                              const double& H)
         throw(InvalidParameter);

         /// Re-define the tropospheric model with explicit weather data.
         /// Typically called just before correction().
         /// @param wx the weather to use for this correction       
      virtual void setWeather(const WxObservation& wx)
         throw(InvalidParameter);

         /// Re-define the heights at which the weather parameters apply.
         /// Typically called whenever setWeather is called.
         /// @param hT height at which temperature applies in meters.
         /// @param hP height at which atmospheric pressure applies in meters.
         /// @param hH height at which relative humidity applies in meters.
      void setHeights(const double& hT,
                      const double& hP,
                      const double& hH);

         /// Define the receiver height; this required before calling
         /// correction() or any of the zenith_delay or mapping_function routines.
      void setReceiverHeight(const double& ht);

   private:
      double height;                // height (m) of the receiver
      double htemp;                 // height (m) at which temp applies
      double hpress;                // height (m) at which press applies
      double hhumid;                // height (m) at which humid applies
      bool validWeather;
      bool validHeights;
      bool validRxHeight;

   };    // end class GGHeightTropModel


   //---------------------------------------------------------------------------------
   /** Tropospheric model developed by University of New Brunswick and described in
    * "A Tropospheric Delay Model for the User of the Wide Area Augmentation
    * System," J. Paul Collins and Richard B. Langley, Technical Report No. 187,
    * Dept. of Geodesy and Geomatics Engineering, University of New Brunswick,
    * 1997. See particularly Appendix C.
    *
    * This model includes a wet and dry component, and was designed for the user
    * without access to measurements of temperature, pressure and relative humidity
    * at ground level. Input of the receiver latitude, day of year and height
    * above the ellipsoid are required, because the mapping functions depend on
    * these quantities. In addition, if the weather (T,P,H) are not explicitly
    * provided, this model interpolates a table of values, using latitude and day
    * of year, to get the ground level weather parameters.
    *
    * Usually, the caller will set the latitude and day of year at the same
    * time the weather is set (if weather is available):
    *
    * @code
    *   NBTropModel nb;
    *   nb.setReceiverLatitude(lat);
    *   nb.setDayOfYear(doy);
    *   nb.setWeather(T,P,H);       // OPTIONAL
    * @endcode
    *
    * Then, when the correction (and/or delay and map) is computed, receiver height
    * should be set before the call to correction(elevation):