Electromagnetic Modeling of Radiowave Propagation and Scattering From Targets in the Atmosphere With a Ray-Tracing Technique

New functionalities of the ray-tracing method applicable in the modeling of radiowave propagation in the atmosphere are presented in this article. First of all, wide-angle approximation is applied to derive the ray-tracing algorithm having no limitations imposed on the elevation angle above the ground. Second, it is proposed to use intensity law known in geometrical optics to account precisely for the complex amplitude along the propagating beam. Consequently, the method can be used to consider rigorously such phenomena as interference, diffraction, and scattering of the wave. Eventually, it is also proposed how to account for the scattering of the beam on a target with known angular characteristic of a radar cross section located on a radar scene. All these novel features of the ray-tracing method make it useful in the analysis of a target positioning error due to atmospheric conditions, which is also presented in this article in comparison to other techniques.