In this overview of groundwave propagation, we address a particular class of propagation scenarios in the presence of surface terrain and atmospheric refractivity. Beginning with idealized analytically solvable models over a smooth spherical Earth, we trace the progression toward more "reality" through physics-based numerical algorithms, operating in the frequency and short-pulse time domain, which take advantage of computational resources. An extensive sequence of simulations for various terrains and atmospheric refractivities, as well as different source-receiver arrangements and operating frequencies, serves to calibrate these algorithms one against the other, and establishes the range of problem parameters for which each is more effective.IEEE Antennas and Propagation Societ

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This article introduces a simple MATLAB radiowave propagation package, SSPE_GUI, for the visualization of EM propagation over non-flat terrain through an inhomogeneous atmosphere, for waves radiated by a horizontally oriented antenna over the ground. The package can be used as an engineering tool to test the effects of various user-specified longitudinal terrain profiles and refractivity variations, as well as guiding and anti-guiding conditions on radiowave propagation, especially for GSM rural coverage planning. It can also be used as an educational aid (virtual tool) in EM lectures, for example, in antennas and propagation, wireless communication, etc

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This article is intended as an educational aid, dealing with high-frequency (HF) electromagnetic wave propagation in guiding environments. It is aimed at advanced senior and first-year graduate students who are familiar with the usual engineering mathematics for wave equations, especially analytic functions, contour integrations in the complex plane, etc., and also with rudimentary saddle-point (HF) asymptotics. Afler an introductory overview of issues and physical interpretations pertaining to this broad subject area, detailed attention is given to the simplest canonical, thoroughly familiar, test environment: a (timeharmonic) line-source-excited two-dimensional infinite waveguide with perfectly conducting (PEC) plane-parallel boundaries. After formulating the Green's function problem within the framework of Maxwell's equations, alternative field representations are presented and interpreted in physical terms, highlighting two complementary phenomenologies: progressing (ray-type) and oscillatory (mode-type) phenomena, culminating in the self-consistent hybrid ray-mode scheme, which usually is not included in conventional treatments at this level. This provides the analytical background for two educational MATLAB packages, which explore the dynamics of ray fields, mode fields, and the ray-mode interplay. The first package, RAY-GUI, serves as a tool to compute and display eigenray trajectories between specified sourcelobserver locations, and to analyze their individual contributions to wave fields. The second package, HYBRID-GUI, may be used to comparatively display range andlor height variations of the wave fields, calculated via ray summation, mode-field summation, and hybrid ray-mode synthesis.