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Microcellular communications propagation model for a city street grid

This paper presents a comprehensive three-dimensional UTD propagation model (for a 1.5 GHz microcell) for a city street grid, including all possible specular wall and ground reflections and corner diffractions in the main street, side-streets and parallel streets of a microcell. This enables the signal propagation through all the possible paths to be tracked to the receiver at various line-of-sight (LOS) or out-of-sight (OOS) positions. Previous papers on such propagation models have included only a limited number of specular reflections and diffractions, and are mostly confined to the LOS region. Our model includes contributions to the received signal from all possible propagation paths, including ground and wall reflections from diffracted and specularly reflected signals both in the LOS and OOS regions. The accuracy of our model is limited only by the assumptions of characterizing the building walls as "smoothed-out" flat surfaces with average permittivity /spl epsiv//sub r/, and conductivity /spl sigma/. The major concepts and formulations for our model have been explained by S.Y Tan and H.S. Tan (see IEEE Trans. Electromagnet. Compat., vol.37, Nov. 1993) and further refinements are briefly described.