I. Introduction
The filters still remain key elements in the modern receiver design. In order to achieve important receiver parameters such as selectivity, sensitivity and dynamic range bandpass filters are typically used. Simultaneously, bandstop filters are largely used in order to suppress undesired signals such as spurious responses, or, in typical transceiver configurations, cross-talk interferences between the transmitter and the receiver. These filters have to match different criteria mainly concerning insertion losses, attenuation, and more important, tuning capability. The tuning capability can be achieved using various solutions. One of them is the use of the MEMS switches [1]–[3]. These switches used in either linear (e.g., varactors) or nonlinear (e.g., switches) modes demonstrated superior RF performance compared to their major (and ‘classical’) competitors such as PIN diodes and field-effect transistor. These superior performances from DC to 100 GHz concern the insertion losses, isolation, cutoff frequency and quality factor.