APPLICATION OF ADAPTIVE ARRAY ANTENNAS TO RADIO-COMMUNICATIONS

In the area of mobile communications, there has been increasing demand and development for new technologies and services such as digitalizat ion and personalization. With this as background, this paper studies t he use of adaptive antenna technology for mobile communication. In the area of mobile communications, the adaptive antenna technology has be en studied with a view to reducing the fading for reception by the mob ile station. In the case of microcells and indoor communication for wh ich an expanded use is anticipated, arrivals of multiple waves from va rious directions are expected even for the base station so that the ap plication of the adaptive antennas to the base stations is effective. In the case of high-speed data transmission such as wireless local wir eless networks (LAN), further reduction of fading and interference is required. Also, the frequency sharing among different radio services i s an area in which the adaptive antenna is useful. Introductions of dy namic control of the systems are expected for mobile communications in time, space, and frequency domains. The adaptive antenna is effective for control in space. The dynamic zone configuration will be a new ap plication area in which, depending on the distributions of the users, the zone shape is varied.