Adaptive antenna arrays for future generation cellular communications networks

This paper addresses the problem of meeting the proliferating demands for mobile telephony within the confinements of the limited radio spectrum allocated to these services. A multiple beam adaptive base-station antenna is proposed as a major system component in an attempt to solve this problem. This novel approach is demonstrated here by employing an antenna array to resolve the angular distribution of the mobile users as seen at the base-station site, and then using this information to direct beams towards the mobiles in both transmit and receive modes. The energy associated with each mobile is thus confined within the addressed volume, greatly reducing the amount of co-channel interference experienced from and by neighbouring co-channel cells. For a given performance criterion, this results in an increase in the spectral efficiency or capacity of the network