Physical characteristics of urban micro-cellular propagation

The characteristics of the propagation in micro-cellular environments at a carrier frequency of 1.98 GHz are investigated by wide band measurements, complemented by theoretical model calculations. The spatial variations of the complex impulse response were measured with a high time resolution allowing via the scattering function the extraction of detailed information about the wave propagation process. The analysis of a large number of different real propagation configurations leads to a characterization of the most relevant urban micro-cellular propagation mechanisms: propagation in lined streets under line-of-sight conditions, coupling into side streets and propagation effects near street intersections. The wide band channel behavior during the transition of a mobile antenna from directly illuminated into shadowed areas has been considered in particular detail, since this is a crucial situation for a mobile communications system