A GSM900 multibeam antenna system test bed for capacity and range improvement trials

A GSM 900 MHz vertically polarised multibeam antenna testbed is presented incorporating a thin 4 beam microstrip planar antenna, a GSM mobile, a GSM base station (BS) a DSP and a personal computer (PC) to control the measurement procedure. The multibeam antenna covers 120/spl deg/ in azimuth with 4 beams offering an impedance bandwidth >10%, a minimum gain of 15.8 dBi for each beam and has dimensions of 710/spl times/800/spl times/12 mm. The static beamforming is performed at the radio frequency (RF). The results demonstrate a carrier to interference (C/I) improvement together with increased received signal strength indication (RSSI).