Magnetically actuated reconfigurable pixelated antenna

In this paper, a 6-element pixelated antenna with reconfigurable resonance frequency and polarization is presented. Reconfiguration is achieved by mechanically connecting/disconnecting 6 movable Ni patches to/from fixed Cu patches, hence realizing patch antennas of different sizes and shape. Each movable patch is a cantilevered plate, micro-fabricated from a Ni layer plated on an RT Duroid substrate. The Ni patch is magnetically actuated by means of an electro-permanent magnet (EPM) placed behind the ground plane of the antenna. Since the Ni patch is itself part of the radiating element, this approach eliminates the need to insert an external switch on the antenna plane. The EPM is placed behind the ground plane, therefore eliminating losses associated with bias lines generally used in pixelated antennas. Most importantly, the very low mechanical contact resistance (as low as 200 mΩ) between the Ni and Cu patch ensures high antenna efficiency. The EPM enables latching of the magnetic actuator, hence resulting in zero static configuration power consumption. Measured resonance frequency reconfigurability, radiation pattern and radiation efficiency agree well with simulated data.