Design of High-Reliability RF MEMS Switch for Reconfigurable 5G Antennas

Abstract

MEMS devices have gained importance during last few decades in different areas. These devices have been used in modern communication systems, radar technologies, imaging technologies and medical instruments. MEMS devices are low cost, reliable, small in size and easy to integrate with other IC fabrication technologies. Switches are used everywhere in communication and satellite systems. Switching can be performed in different ways using PIN diodes, transistors and MEMS devices. Diodes and transistors are electronic components and provide high speed switching but having high insertion loss and low isolation. MEMS switches offer a lot of advantages over the conventional switches such as high isolation, low power consumption, low isolation, better harmonic re jection and reduced size. But the integration of RF MEMS switches with antennas is still very challenging due to dielectric discharge, stiction and par asitic problems. This study focuses on the electrostatically actuated single pole double throw (SPDT) switch which will be used in future 5G communication systems. The proposed switch is composed of three different switches designed separately in order to reduce the space and enhance the performance. All the switches are actuated simultaneously hence no voltage switching is required. The complete design is composed of two shunt switches and one series switch. The air gap is provided as insulating layer to provide maximum isolation within the fabrication limits. The electrical parameters of the proposed switch were simulated in CST software while the mechanical parameters were analyzed using Comsol software.