Reconfigurable Split Ring Resonators by MEMS-Driven Geometrical Tuning

A novel approach for dynamic microwave modulation is proposed in the form of reconfigurable resonant circuits. This result is obtained through the monolithic integration of double split ring resonators (DSRRs) with microelectromechanical actuators (MEMS) for geometrical tuning. Two configurations were analyzed to achieve a controlled deformation of the DSRRs' metamaterial geometry by mutual rotation or extrusion along the azimuthal direction of the two constituent rings. Then, the transfer function was numerically simulated for a reconfigurable MEMS-DSRR hybrid architecture where the DSRR is embedded onto a realistic piezo actuator chip. In this case, a 370 MHz resonance frequency shift was obtained under of a 170 µm extrusion driven by a DC voltage. These characteristics in combination with a high Q factor and dimensions compatible with standard CMOS manufacturing techniques provide a step forward for the production of devices with applications in multiband telecommunications and wireless power transfer and in the IoT field.