Dielectric filter with multiple resonators

A laminated dielectric filter comprising a strip line resonator electrode layer forming plural strip line resonators, and a capacity electrode layer forming input and output coupling capacitors and an interstage coupling capacitor, wherein the strip line resonator electrode layer and the capacity electrode layer are sandwiched by two shield electrode layers, wherein a space between the two shield electrode layers is filled with a dielectric, and wherein a thickness of a space between the strip line resonator electrode layer and the capacity electrode layer is less than a thickness of a space between the strip line resonator electrode layer and one of the shield electrode layers and a thickness of a space between the capacity electrode layer and the other of the shield electrode layers, wherein an interstage coupling capacity electrode, or input and output coupling capacity electrode, or loading capacity electrode formed on the capacity electrode layer has a dent narrowed in the electrode width in the region overlapping with the outer edge of the strip line resonator electrode of the strip line resonator electrode layer.

A laminated dielectric filter comprising a strip line resonator electrode layer forming plural strip line resonators, and a capacity electrode layer forming input and output coupling capacitors and an interstage coupling capacitor, wherein the strip line resonator electrode layer and the capacity electrode layer are sandwiched by two shield electrode layers, wherein a space between the two shield electrode layers is filled with a dielectric, and wherein a thickness of a space between the strip line resonator electrode layer and the capacity electrode layer is less than a thickness of a space between the strip line resonator electrode layer and one of the shield electrode layers and a thickness of a space between the capacity electrode layer and the other of the shield electrode layers, wherein the laminated dielectric filter has an input and output coupling capacity electrode on the capacity electrode layer, and the strip line resonator has a front end short-circuit structure, and moreover the input and output coupling capacity electrode and strip line resonator are coupled capacitively at an intermediate position between the open end and short-circuit end of the strip line resonator.

A laminated dielectric filter comprising a first strip line resonator disposed on a first shield electrode through a first dielectric sheet with a thickness t.sub.1, second to n-th strip line resonators disposed on the first strip line resonator through second to n-th dielectric sheets with thicknesses of t.sub.2 to t.sub.n (where n is greater than two), and a second shield electrode disposed on the n-th strip line resonator through an (n+1)-th dielectric sheet with thickness t.sub.n+1, setting a maximum thickness of t.sub.2 to t.sub.n smaller than t.sub.1 or t.sub.n+1, wherein the first dielectric sheet and the (n+1)-th dielectric sheet includes a laminated plurality of thin dielectric sheets, whereby an input and output coupling capacity electrode is formed in one of the thin dielectric sheets of the first dielectric sheet and in one of the thin dielectric sheets of the (n+1)-th dielectric sheet.