A reconfigurable dual frequency switched beam antenna array and phase shifter using PIN diodes

Reconfigurable antennas have received much attention in the past years playing an important role in the design of smart and adaptive systems. They have been benefited from recent improvements in the performance of the existing switching technologies. In particular, integrating active devices such as MEMS switches [1] or solid state switches [2] in antennas and microwave circuits have been proved to be useful for a wide range of applications. In this paper a dual frequency reconfigurable microstrip phase array with beam steering capability for operation at 4.7GHz and 7.5GHz is presented. The system is composed of a dual frequency (DF) reconfigurable antenna and a single feed dual frequency reconfigurable switched line phase shifter. Both selectable features, frequency and progressive phase between antennas, are achieved using PIN diodes. Only one of the two operating bands remains active at the same time, rejecting the non-active frequency spurious and the need of an external diplexer. Progressive phases between antennas of {+45,+135,−45,−135} for both frequencies can be selected to generate a switched beam with maximums placed at {15,45,−15,45} and {13,30,−13,30{ degrees respectively at 4.7GHz and 7.5GHz.