Antenna characteristics in vertically Gaussian distributed mobile radio propagation

The antenna characteristics of land mobile radio propagation environments can be estimated by considering the incoming wave distribution. The antenna height dependence of the spread width of the incoming wave distribution in urban areas is described. Theoretical and experimental investigations of required antenna spacing for vertical space diversity, effective gain of antenna dependence on antenna height, and null-filling of the vertical radiation pattern of a base station antenna for land mobile radios are presented. It is shown that as antenna height becomes equal to or less than the average of surrounding building height the effective antenna gain is limited to no higher than about 10 dB. Furthermore, for a mobile station, it does not improve more than approximately 6 dB. Existing null points in multipath propagation environments are sufficiently filled up by an incoming wave spread of only 0.2 degrees .<>