1 //============================================================================== 2 // 3 // This file is part of GPSTk, the GPS Toolkit. 4 // 5 // The GPSTk is free software; you can redistribute it and/or modify 6 // it under the terms of the GNU Lesser General Public License as published 7 // by the Free Software Foundation; either version 3.0 of the License, or 8 // any later version. 9 // 10 // The GPSTk is distributed in the hope that it will be useful, 11 // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 // GNU Lesser General Public License for more details. 14 // 15 // You should have received a copy of the GNU Lesser General Public 16 // License along with GPSTk; if not, write to the Free Software Foundation, 17 // Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA 18 // 19 // This software was developed by Applied Research Laboratories at the 20 // University of Texas at Austin. 21 // Copyright 2004-2020, The Board of Regents of The University of Texas System 22 // 23 //============================================================================== 24 25 //============================================================================== 26 // 27 // This software was developed by Applied Research Laboratories at the 28 // University of Texas at Austin, under contract to an agency or agencies 29 // within the U.S. Department of Defense. The U.S. Government retains all 30 // rights to use, duplicate, distribute, disclose, or release this software. 31 // 32 // Pursuant to DoD Directive 523024 33 // 34 // DISTRIBUTION STATEMENT A: This software has been approved for public 35 // release, distribution is unlimited. 36 // 37 //============================================================================== 38 39 /// @file SolidEarthTides.hpp 40 /// Implement the formula for the displacement of a point fixed to the solid Earth 41 /// due to the solid Earth tides resulting from the influence of the Sun and Moon. 42 /// Reference IERS Conventions (1996) found in IERS Technical Note 21 (IERS). 43 /// NB. Currently only the largest terms are implemented, yielding a result accurate 44 /// to the millimeter level. Specifically, IERS pg 61 eq 8 and IERS pg 65 eq 17. 45 /// The second equation referenced here is the permanent component. 46 /// Class SolarSystem may be used to get Solar and Lunar ephemeris information, 47 /// including position and mass ratios. 48 49 //------------------------------------------------------------------------------------ 50 #ifndef SOLID_EARTH_TIDES_INCLUDE 51 #define SOLID_EARTH_TIDES_INCLUDE 52 53 //------------------------------------------------------------------------------------ 54 // system 55 // GPSTk 56 #include "Exception.hpp" 57 #include "EphTime.hpp" 58 #include "Position.hpp" 59 #include "Triple.hpp" 60 #include "IERSConvention.hpp" 61 62 namespace gpstk 63 { 64 65 //--------------------------------------------------------------------------------- 66 /// Compute the site displacement due to solid Earth tides for the given Position 67 /// (assumed to be fixed to the solid Earth) at the given time, given the position 68 /// of the site of interest, positions and mass ratios of the sun and moon. 69 /// Return a Triple containing the site displacement in ECEF XYZ coordinates with 70 /// units meters. 71 /// Reference IERS Conventions (1996) found in IERS Technical Note 21 72 /// and IERS Conventions (2003) found in IERS Technical Note 32 73 /// and IERS Conventions (2010) found in IERS Technical Note 36. 74 /// NB. Currently only the largest terms are implemented, yielding a result 75 /// accurate to the millimeter level. Specifically, TN21 pg 61 eq 8 and 76 /// TN21 pg 65 eq 17. 77 /// @param Position site Nominal position of the site of interest. 78 /// @param EphTime time Time of interest. 79 /// @param Position Sun Position of the Sun at time 80 /// @param Position Moon Position of the Moon at time 81 /// @param double EMRAT Earth-to-Moon mass ratio (default to DE405 value) 82 /// @param double SERAT Sun-to-Earth mass ratio (default to DE405 value) 83 /// @param IERSConvention IERS convention to use (default IERS2010) 84 /// @return Triple Displacement vector, ECEF XYZ in meters. 85 /// @throw Exception 86 Triple computeSolidEarthTides(const Position site, 87 const EphTime time, 88 const Position Sun, 89 const Position Moon, 90 const double EMRAT=81.30056, 91 const double SERAT=332946.050894783285912, 92 const IERSConvention iers=IERSConvention::IERS2010); 93 94 //--------------------------------------------------------------------------------- 95 /// Compute the site displacement due to rotational deformation due to polar motion 96 /// for the given Position (assumed to fixed to the solid Earth) at the given time, 97 /// given the polar motion angles at time (cf.EarthOrientation) and the IERS 98 /// convention to use. Return a Triple containing the site displacement in 99 /// ECEF XYZ coordinates with units meters. 100 /// Reference IERS Conventions (1996) found in IERS Technical Note 21, ch. 7 pg 67. 101 /// @param Position site Nominal position of the site of interest. 102 /// @param EphTime time Time of interest. 103 /// @param double xp,yp Polar motion angles in arcsec (cf. EarthOrientation) 104 /// @param IERSConvention IERS convention to use (default IERS2010) 105 /// @return Triple disp Displacement vector, ECEF XYZ in meters. 106 /// @throw Exception 107 Triple computePolarTides(const Position site, const EphTime time, 108 const double xp, const double yp, 109 const IERSConvention iers=IERSConvention::IERS2010); 110 111 } // end namespace gpstk 112 113 #endif // SOLID_EARTH_TIDES_INCLUDE 114 // nothing below this 115 116