The antenna with switchable far-field patterns for mobile communication systems

The results of theoretical and experimental investigations of an oscillator antenna within 900 MHz frequency band are considered. The antenna consists of three alternatively active arms installed circumferentially on the cylindrical screen face. Switching is provided by a pin-diode circuit. Two passive arms operate as reflectors for the active one. As a result one of three possible far-field patterns is formed with beamwidth 120/spl deg/.