# US 2020/0403286 A1 · Dielectric cavity notch filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0403286 A1 - Document ID: US20200403286A1 - Status: Published application - Kind: A1 - Application number: 16/904,252 - Filed: 2020-06-17 - Published: 2020-12-24 - Earliest claimed: 2019-06-19 - Assignees: Knowles Cazenovia, Inc. - Applicants: Knowles Cazenovia, Inc. - Inventors: Jared Parker Burdick - Web page: https://patentgrep.com/patent/US20200403286A1 ## CPC - H01P 1/2002: {Dielectric waveguide filters (H01P1/212, H01P1/213, H01P1/215, H01P1/219 take precedence)} - H01P 7/10: Dielectric resonators - H05K 1/0233: {Filters, inductors or a magnetic substance} - H05K 1/0243: {Printed circuits associated with mounted high frequency components} - H05K 3/303: with surface mounted components (H05K3/32 takes precedence) - H05K 1/0239: {Signal transmission by AC coupling} - H05K 2201/1006: Non-printed filter - H01P: WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE (operating at optical frequencies G02B) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A band stop filter can include a circuit board having a first surface and an opposing second surface. The circuit board can have a transmission line on the first surface. The band stop filter can include a dielectric cavity resonator physically coupled to the second surface of the circuit board. The dielectric cavity resonator can have a coupling aperture configured to magnetically couple the dielectric cavity resonator to the transmission line, and to cause excitation of the dielectric cavity resonator in a second order transverse electric (TE) mode. ## Claims ### Claim 1 A band stop filter comprising: a circuit board having a first surface and an opposing second surface, the circuit board having a transmission line on the first surface; and a dielectric cavity resonator physically coupled to the second surface of the circuit board, and having a coupling aperture configured to magnetically couple the dielectric cavity resonator to the transmission line, and to cause excitation of the dielectric cavity resonator in a second order transverse electric (TE) mode. ### Claim 2 (depends on 1) The band stop filter of claim 1, wherein the coupling aperture corresponds to a loop-shaped gap on a metallized surface of the circuit board. ### Claim 3 (depends on 1) The band stop filter of claim 1, wherein the dielectric cavity resonator comprises a metal-coated ceramic substrate. ### Claim 4 (depends on 1) The band stop filter of claim 1, wherein the dielectric cavity resonator has a coefficient of thermal expansion (CTE) substantially equal to a CTE of the circuit board. ### Claim 5 (depends on 1) The band stop filter of claim 1, comprising a plurality of dielectric cavity resonators physically coupled to the circuit board, each of the plurality of dielectric cavity resonators magnetically coupled to the transmission line via a respective coupling aperture. ### Claim 6 (depends on 1) The band stop filter of claim 1, wherein the dielectric cavity resonator has a resonance frequency equal to a notch frequency of the band stop filter. ### Claim 7 (depends on 1) The band stop filter of claim 1, comprising a conductive layer arranged between the circuit board and the dielectric cavity resonator, the conductive layer having a coupling aperture that is aligned with the coupling aperture of the dielectric cavity resonator. ### Claim 8 (depends on 7) The band stop filter of claim 7, wherein the coupling aperture of the conductive layer comprises a loop-shaped gap on the conductive layer. ### Claim 9 (depends on 8) The band stop filter of claim 8, wherein the loop-shaped gap has a circular or elliptical structure. ### Claim 10 (depends on 1) The band stop filter of claim 1, wherein the circuit board includes a single layer substrate that is at least partially coated with copper on opposing sides of the single layer substrate. ### Claim 11 (depends on 1) The band stop filter of claim 1, wherein the coupling aperture is aligned with the transmission line and separated from the transmission line by at least a thickness of the circuit board. ### Claim 12 (depends on 1) The band stop filter of claim 1, wherein a side of the transmission line facing away from the circuit board is coated with an insulator material. ### Claim 13 (depends on 1) The band stop filter of claim 1, wherein the dielectric cavity resonator is configured to attenuate a signal at a frequency within a frequency range of 2 GHz to 30 GHz. ### Claim 14 A method comprising: providing a circuit board having a first surface and an opposing second surface, the circuit board having a transmission line on the first surface; and physically coupling a dielectric cavity resonator to the second surface of the circuit board, enabling a coupling aperture of the dielectric cavity resonator to magnetically couple the dielectric cavity resonator to the transmission line, and to cause excitation of the dielectric cavity resonator in a second order transverse electric (TE) mode. ### Claim 15 (depends on 14) The method of claim 14, further comprising physically coupling a plurality of dielectric cavity resonators to the circuit board, enabling each of the plurality of dielectric cavity resonators to magnetically couple to the transmission line via a respective coupling aperture. ### Claim 16 (depends on 14) The method of claim 14, further comprising sizing the dielectric cavity resonator to have a resonance frequency equal to a notch frequency of the band stop filter. ### Claim 17 (depends on 14) The method of claim 14, further comprising providing a conductive layer between the circuit board and the dielectric cavity resonator, the conductive layer having a coupling aperture that is aligned with the coupling aperture of the dielectric cavity resonator. ### Claim 18 (depends on 17) The method of claim 17, further comprising forming a coupling aperture on the conductive layer that comprises a loop-shaped gap on the conductive layer. ### Claim 19 (depends on 14) The method of claim 14, further comprising forming the coupling aperture as a loop-shaped gap on a metallized surface of the dielectric cavity resonator. ### Claim 20 (depends on 14) The method of claim 14, further comprising aligning the coupling aperture with the transmission line while separated from the transmission line by at least a thickness of the circuit board.