Specular reflections from high-rise buildings in 900 MHz cellular systems

Wideband radio propagation measurements have been performed in Dallas with special emphasis on specular reflections from high-rise buildings as they typically appear in downtown areas of major US cities. The measurements were carried out at 908 MHz with the RCS 900 channel sounder. Specular reflections of groups of high-rise buildings, and in the vicinity of isolated buildings were measured. The results are presented both in the form of impulse responses and in a statistical manner along the chosen routes. It is found that reflections may give rise to two types of problems: they can cause considerable time spreads in a cell and significant signal levels in areas that are normally regarded as belonging to other cells