Several ways of ‘modulating’ the base station antennas for wireless communication are proposed, in the thesis. The idea is to maximize the capacity of wireless wideband networks providing a variety of services with serious demands on transmission rates. In the effort of maximizing the capacity, it is confirmed that the tilted radiation pattern of the base station antenna can improve the system’s performance. A generalized method for determining the optimum tilt angle is defined by taking into consideration the most important factors affecting the performance. Moreover, the relation between the capacity, the Signal-to-Interference ration and the tilt angle is defined. Finally, specific configurations for adaptive and switched beam antenna systems are proposed.