tropo_sa.m

这是国外关于卫星导航方面一书的源代码

function [dr]=tropo_sa(kosinus_z,t,p,h)
% -----------------------------------------------------------------------------
% GPSLab:   TROPO_SA.M
%
% Correction of the tropospheric refraktion following the model of 
% Saastamoinen Model (Simplified)
%
% sufficient for educational purposesto explain principle and effect
%
% How: [dr]=tropo_sa(kosinus_z,t,p,h);
% Input:   kosinus_z Cosine (zenithal angle) from the direction cosines Geocenter to Topocenter
%                    and Topocenter to Satellite, corrected by aberration (earth rotation)
%          t         Temperature in 癈 following the Standard Atmosphere
%          p         Absolute Pressure in mbar following the Standard Atmosphere
%          h         Relative Humidity in Percent following the Standard Atmosphere
%
% Output:  dr [m]    Tropospheric Correction of the measurement
%                    between receiver and satellite
%
% Standard atmosphere:   like given in the calling program
%
% Literature: Hofmann-Wellenhof et al. (1992), Klein (1990), ...
% see also: TROPO_MH.M
% -----------------------------------------------------------------------------
% (c) iapg, zebhauser, 1996-06-17, 1999-10-11

% Partial pressure of the steam
e=h./100.*exp(-37.2465+0.213166.*(t+273)-0.000256908.*(t+273).^2);

% Zenithal Delay
dr0=0.002277.*(p+(1255./(273+t)+0.05).*e);

% Mapping to actual zenithal angle
dr=dr0./kosinus_z;


% (c) iapg, zebhauser, 1996-06-17, 1999-10-11