Distributed element radio frequency filter
AssigneeKnowles Cazenovia, Inc.
InventorJared P. BURDICK
Life of this patent
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Abstract
A distributed element radio frequency (RF) filter includes one or more fully grounded half-wave resonators located between first and second resonators electrically coupled to corresponding input/output (I/O) interfaces proximate corresponding ends of a dielectric substrate. Each of the one or more half-wave resonators comprise a U-shaped or omega-shaped resonator portion located between first and second end portions electrically connected to a ground plane at a common side of the substrate. Each resonator has an electrical length that is nominally one-half a wavelength of a center frequency of the filter. The filter can optionally include a conductive cover over the resonators.
Claims21
A distributed-element radio frequency (RF) filter comprising:
- a ceramic 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 electrically connected to a first input/output (I/O) interface proximate a first end of the substrate;
- a second resonator on the second surface of the substrate, the second resonator electrically connected to a second I/O interface proximate a second end, opposite the first end, of the substrate;
- one or more intermediate resonators on the second surface of the substrate, the one or more intermediate resonators located between the first and second resonators,
- each of the first, second and one or more intermediate resonators having an electrical length that is nominally one-half a wavelength of a center frequency of the filter,
- each of the first, second and one or more intermediate resonators comprising a resonator portion between first and second resonator end portions electrically connected to the ground plane by a conductive wall proximate a common side of the substrate, wherein each resonator at least partially surrounds a portion of the surface of the substrate on which the resonator is located.
A distributed-element radio frequency (RF) filter comprising:
- a dielectric substrate comprising a ground plane located on a surface of the substrate;
- first and second resonators located on a surface of the substrate opposite the ground plane, each of the first and second resonators electrically coupled to a corresponding input/output (I/O) interface proximate a corresponding end of the substrate;
- and
- one or more U-shaped or omega-shaped resonators located on the surface opposite the ground plane and between the first and second resonators, each U-shaped or omega-shaped resonator comprising first and second resonator end portions electrically connected to the ground plane by one or more conductors proximate a common side of the substrate,
- wherein each of the resonators has an electrical length that is nominally one-half a wavelength of a center frequency of the filter.
A distributed-element radio frequency (RF) filter comprising:
- a dielectric substrate between a ground plane at a surface of the substrate and a plurality of resonators at an opposite surface of the substrate;
- the plurality of resonators comprising:
- first and second resonators each electrically coupled to a corresponding input/output (I/O) interface proximate a corresponding end of the substrate;
- and
- one or more intermediate resonators located between the first and second resonators,
- each of the one or more intermediate resonators comprising a resonator portion between first and second end portions electrically connected to the ground plane by one or more conductors proximate a common side of the substrate.
Dependencies are inferred from the claim text.