A DETERMINISTIC APPROACH FOR THE MODELING OF WAVE-PROPAGATION AROUND BUILDINGS

In this paper the Uniform Theory of Diffraction (UTD) is used to calcu late the electric field strength near perfectly conducting obstacles. In case suppression of an interfering radio wave is wanted, a paramete r of interest is the site shielding factor, which expresses the attenu ation of an electromagnetic wave that propagates around an obstacle. S ite shielding results are presented for a thin screen and a block-type obstacle, and good agreement between theory and experiment is found f or both cases. Another application of the site shielding concept is th e prediction of the field strength in an urban environment. For this a pplication the use of a versatile block-type obstacle seems more appro priate. To demonstrate the capability of the models presented, the fie ld strength near a cluster of obstacles is calculated. It is explained how communication parameters such as the Doppler and the delay-Dopple r spectrum can be derived from the wave analysis. The model proposed c an be of use for the planning and analysis of (future) telecommunicati ons systems and the understanding of the behavior of the (mean) signal strength in urban environments.