MEMS 3-Bit and 4-Bit Phase Shifters Using Two Back-to-Back Switching Networks

This chapter focuses on the development of a Ka-band 3-bit microelectromechanical systems (MEMS) phase shifter using two back-to-back single-pole eight-throw MEMS switches. It draws on development of a K-band 4-bit phase shifter using two single-pole sixteen-throw (SP16T) switches. One of the major challenges of MEMS phase shifters is to achieve good reliability without compromising its microwave performance. In order to obtain optimum device performance and compact size, the reference line of the phase shifter is optimized to 450 µm. Reliability measurements are performed on the phase shifter at three different power levels, and corresponding changes in average loss and phase errors are recorded at 35 GHz. Different topologies of a 4-bit phase shifter are designed and optimized using two SP16T switches with different delay and reference line combinations. The SP16T switch is a stand-alone component in the modern switched-beam satellite antenna system.