Ultra-Wideband Pattern Reconfigurable Antenna Design Based on Parasitic Elements

An ultra-wideband pattern reconfigurable antenna is proposed in this paper. The pattern reconfigurable antenna is composed of a driving dipole antenna with parasitic elements integrated with PIN diodes. The patterns can be steered by selecting ON/OFF states of the PIN diode. PIN diodes with low equivalent capacitance in OFF state are selected to increase the pattern reconfigurable bandwidth. The working mechanism of PIN diodes to improve the bandwidth is investigated. The smaller the equivalent capacitance of the PIN diodes in OFF state, the wider the pattern reconfigurable bandwidth. And multiple PIN diodes in series are the most suitable solution for improving the pattern reconfigurable bandwidth. Finally, a pattern reconfigurable antenna integrated with four MADP000907 diodes was designed. The pattern reconfigurable bandwidth is about 50%.