ABSTRACT
To provide mobile communication services to subscribers, the radio links in modern wireless systems cover relatively small distances. The short links allow for reuse of the spectrum in different regions, and work with lower radiated power to save battery life. Because the customers for modern wireless applications are predominately among buildings, the buildings have the greatest influence on the propagation over short distances. The channel characteristics are found to vary from one mobile location to another, so that they are usually described by means of statistical measures and distribution functions. Outside of the high-rise core, cities are composed of rows of buildings having nearly uniform height, with an occasional high building or cluster of high buildings. The buildings are taller and closer together near the core, but become lower and more spread farther from the core and into the suburbs.
