Design, Analysis and Comparison of Various MEMS Switches for Reconfigurable Planar Antenna

This paper presents design and analysis of a novel beam for electrostatically actuated Radio Frequency Micro Electro Mechanical Systems (RF MEMS) shunt switches. In the proposed beam design, geometrical variations in terms of structure shape, material, gap, introduction of holes and changing the length and width of anchor have led to good RF performance. The holes in the beam (maximum up to 60% of total area of upper electrode) not only make the smooth mechanical movement of the beam but also result in low spring constant. The designed RF-MEMS switches are actuated electrostatically, and can be operated at low pull-in voltage, ranging from 0.5 V to 22 V with negligible power consumption. Proposed RF MEMS switches can easily be integrated in mobile RF front end section alongwith microstrip antenna in order to provide reconfigurabilty in frequency. Various shapes of planar antenna are also discussed which are suitable with proposed shunt switches. The effect of microstrip line and coplanar waveguide as transmission line are also studied.