RAY TRACING AND APPLICATIONS TO AN EVAPORATION DUCT MODEL BASED ON DATA FROM OCEANOGRAPHIC BUOY SENSORS
Keywords:amplitude, evaporation duct, microwave, parabolic equations, ray tracing, troposphere
The two-dimensional ray tracing method allows an easy and fast modeling of tropospheric propagation in the microwave frequency range. A version of this method that determines ray trajectories, amplitudes and delays of the electromagnetic field, as well as the propagation loss in a two-dimensional inhomogeneous environment will be described. The implemented algorithm may consider generalized maps of modified refractivity (or refractive modulus), including not only the vertical gradients, but also their horizontal variations along the path between transmitter and receiver. Next, the present paper will discuss the results from the application of a model of evaporation duct height to data from instruments installed in sea buoys located along the Brazilian coast. Finally, the results from the application of the ray-tracing model to evaporation ducts will be presented, to analyze the propagation of microwave signals in the maritime environment. These results will also be compared with corresponding ones from the software Advanced Refractive Effects Prediction System 3.6, based on the numerical solution of a parabolic equation.
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