| This thesis presents research into monolithic, tunable microwave phase shifter circuits. Phase shifters have many applications, but this work focuses on a phase shifter for use in adaptive antenna arrays. This application requires high phase shift per unit loss, a continuously tunable phase range, small size and weight, and low cost.;This work describes the modeling, simulation, design, fabrication and measurement of a Distributed MEMS Transmission Line Phase Shifter, which has demonstrated performance better than the current state of the art.;Microwave phase shifters based on the concept of a loaded transmission line were selected as the base platform for the design. Tunability has been achieved by means of introducing MicroElectroMechanical Systems (MEMS), whereby physical structure movement is used to alter electrical characteristics. MEMS technology has been utilized here to create tunable microwave capacitors, which are used to load a coplanar waveguide transmission line and create a phase shifter. A custom fabrication process has been developed to construct these RF compatible MEMS devices. |
