A versatile threedimensional ray tracing computer program for radio waves in the ionosphere
Abstract
This report describes an accurate, versatile FORTRAN computer program for tracing rays through an anisotropic medium whose index of refraction varies continuously in three dimensions. Although developed to calculate the propagation of radio waves in the ionosphere, the program can be easily modified to do other types of ray tracing because of its organization into subroutine. The program can represent the refractive index by either the AppletonHartree or the SenWyller formula, and has several ionospheric models for electron density perturbations to the electron density (irregularities), the earth's magnetic field and electron collision frequency. For each path, the program can calculate group path length, phase path length, absorption, Doppler shift due to a timevarying ionosphere, and geometrical path length.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 October 1975
 Bibcode:
 1975STIN...7625476J
 Keywords:

 Computer Programs;
 Earth Ionosphere;
 Radio Waves;
 Atmospheric Models;
 Doppler Effect;
 Fortran;
 Hartree Approximation;
 Ionospheric Electron Density;
 Numerical Integration;
 Partial Differential Equations;
 Radio Transmission;
 Communications and Radar