Propagation models for hilly terrain based on ray optic methods

Yıldırım, Erkan Ersin
In RF propagation path loss modeling, numerical methods may not be useful since they require very long computation times because electrically very large objects may be located in the terrain. Ray optic methods such as Geometrical Optics (GO) or Geometrical Theory of Diffraction (GTD) are more commonly used in propagation problems as well as the empirical models. Although ray optics methods are designed for very high frequency applications, they provide quite accurate path loss estimations in hilly terrain including electrically very large obstructions. In this thesis, ray optic methods are reviewed and applied to various different basic geometries. Computed results are compared with those obtained by the Longley-Rice model which is based on the use of empirical data. Weak and strong features of both ray optic methods and empirical methods are discussed. Finally, by using the results obtained previously, how to optimize the receiver parameters in order to obtain the maximum EM signal radiated by a transmitter in the hilly terrain is discussed.


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Citation Formats
E. E. Yıldırım, “Propagation models for hilly terrain based on ray optic methods,” M.S. - Master of Science, Middle East Technical University, 2015.