Pattern reconfigurable antenna for adaptive multi-input multi-output switching applications

A novel pattern reconfigurable antenna is presented for adaptive multi-input multi-output (MIMO) switching applications. The proposed antenna provides two different radiation patterns by controlling the bias voltage of PIN diode switches. When the switch turns on, the maximum radiation intensity occurs at boresight, which is similar to a microstrip patch antenna. When the switch turns off, the maximum radiation intensity occurs at right angles to boresight, which is similar to a monopole antenna. In order to have identical resonant frequencies of 2.3 GHz at both states, the position of the switches is adjusted.