Multi-layered planar filters based on aperture coupled, dual mode microstrip or stripline resonators

A new class of planar filters is introduced that is based on a multilayered stack of dual mode stripline or microstrip resonators coupled through irises. This planar stack configuration can be used to realize any of the filter types that are currently implemented using dual mode cavities or dielectric resonators including elliptic function and/or self-equalized responses required for satellite applications. The stacked planar structure offers dramatic reductions in size, mass, and potentially cost as compared to previous cavity designs. This class of filters is ideally suited for fabrication using thin-film, high-temperature superconductors for high-Q performance. Novel, multilayer, planar filters are introduced, and experimental results are presented. >