A propagation model is presented in this paper for predicting the field strength in microcellular environments. According to the Geometrical Theory of Diffraction, the total field at a given observation point is calculated by summing the Geometrical Optics contributions and the field diffracted by the edges of each structure. The diffraction contributions are here evaluated by means of a Uniform Asymptotic Physical Optics solution to the corresponding canonical problem. Such a solution, expressed in terms of the standard transition function of the Uniform Theory of Diffraction, has resulted to be able to compensate the Geometrical Optics discontinuities at the shadow boundaries. In this framework, the structures are treated as constituted by lossy dielectric materials assumed to be non penetrable. The effectiveness of the here proposed model has been tested in some typical scenarios by means of comparisons with the Finite Difference Time Domain method.
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