Dielectric strength of micromechanically tunable microstrip lines

The paper presents a research of maximum transmit power in tunable microstrip line, limited by electric breakdown phenomena in dielectric part of the device in process of electromechanical control. It is demonstrated, that electric breakdown strength of tunable microstrip line is not worse that in regular microstrip line and improves as signal electrode moves away of substrate's surface. Power capacity of tunable microstrip line improves in the line with wider signal electrode, thicker substrate, and lower substrate permittivity. These requirements contradict tuning efficiency, thus practical design should be based on trade-off between them.