US 12,431,601 B2
Printed microstrip filter
David Bates, Fayetteville, NY (US)
Assigned to Knowles Cazenovia, Inc., Cazenovia, NY (US)
Filed by Knowles Cazenovia, Inc., Cazenovia, NY (US)
Filed on Apr. 24, 2023, as Appl. No. 18/138,317.
Claims priority of provisional application 63/334,952, filed on Apr. 26, 2022.
Prior Publication US 2023/0344101 A1, Oct. 26, 2023
Int. Cl. H01P 1/203 (2006.01); H01P 1/212 (2006.01); H01P 7/08 (2006.01)
CPC H01P 1/20309 (2013.01) [H01P 1/212 (2013.01); H01P 7/082 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A printed film radio frequency microstrip bandpass filter comprising:
a dielectric substrate having a ground plane on a first surface of the substrate;
a first resonator on a second surface, opposite the first surface, of the substrate, the first resonator having a length between lateral side portions of the substrate, opposite ends of the first resonator coupled to the ground plane;
a first input/output (I/O) interface on the substrate connected to the first resonator by a conductor;
a second resonator on the second surface of the substrate, the second resonator having a length between the lateral side portions of the substrate, opposite ends of the second resonator coupled to the ground plane;
a second I/O interface on the substrate connected to the second resonator by a conductor;
one or more intermediate resonators on the second surface of the substrate between the first resonator and the second resonator, each of the one or more intermediate resonators having a length between the lateral side portions of the substrate and an electrical wavelength that is one-half a wavelength of a center frequency of the bandpass filter,
opposite ends of the one or more intermediate resonators directly electrically connected to the ground plane by corresponding conductors.