Triple-mode resonator and a waveguide filter comprising the same

{
  "publication_number": "US12355129B2",
  "country": "US",
  "kind": "B2",
  "title": "Triple-mode resonator and a waveguide filter comprising the same",
  "abstract": "The present disclosure relates to a triple-mode resonator, comprising: a main body made of a dielectric material and having a cuboid shape defining three orthogonal axes (x, y, z) substantially aligned with faces of the main body; and a conductive coating covering all of the main body except portions of the faces of the main body which defines at least one coupling aperture through which a signal can be coupled into and/or out of the main body, wherein the coupling aperture has a closed shape comprising a first and a second main edges extending along two of the axes respectively and a third main edge extending neither parallel nor perpendicular to the first and second main edges, the general shape and size and location of the coupling aperture is mainly determined by the first, second and third main edges, and the coupling aperture is configured in such a manner that desired three dominant resonance modes can be excited independently in the resonator by an input signal introduced therethrough.",
  "claims": [
    "1. A triple-mode resonator, comprising: a main body made of a dielectric material and having a cuboid shape defining three orthogonal axes (x, y, z) substantially aligned with faces of the main body; and a conductive coating covering all of the main body except portions of the faces of the main body which defines at least one coupling aperture through which a signal can be coupled into and/or out of the main body, wherein the at least one coupling aperture has a closed shape comprising a first and a second main edges extending along two of the axes respectively and a third main edge extending neither parallel nor perpendicular to the first and second main edges, a general shape and size and location of the at least one coupling aperture is mainly determined by the first, second and third main edges, and the at least one coupling aperture is configured in such a manner that desired three dominant resonance modes can be excited independently in the resonator by an input signal introduced therethrough, and wherein the third main edge is in the form of an arc segment.",
    "2. The triple-mode resonator according to claim 1, wherein the at least one coupling aperture is substantially triangle shaped.",
    "3. The triple-mode resonator according to claim 1, wherein the arc segment curves towards an inside of the at least one coupling aperture, wherein an arc center of the arc segment is a center of a face where the arc segment is located.",
    "4. The triple-mode resonator according to claim 1, wherein the at least one coupling aperture further comprises a fourth edge extending obliquely with respect to the first and second main edges so as to meet the first and second main edges.",
    "5. The triple-mode resonator according to claim 4, wherein the fourth edge is located in a corner where extensions of the first and second main edges meet.",
    "6. The triple-mode resonator according to claim 1, wherein the first and second main edges or extensions of the first and second main edges meet in an area close to a right-angled corner in a face of the main body.",
    "7. The triple-mode resonator according to claim 1, wherein an end of the first main edge connects to an end of the third main edge that is close to the first main edge, by a fifth edge perpendicular to the first main edge.",
    "8. The triple-mode resonator according to claim 1, wherein an end of the second main edge connects to an end of the third main edge that is close to the second main edge, by a sixth edge perpendicular to the second main edge.",
    "9. The triple-mode resonator according to claim 1, wherein one coupling aperture of the at least one coupling aperture is provided in a face of the main body as input coupling aperture(s).",
    "10. The triple-mode resonator according to claim 9, wherein another one coupling aperture of the at least one coupling aperture is provided in a face of the main body as output coupling aperture(s), and the face where the output coupling aperture(s) is located is substantially opposite to the face where the input coupling aperture(s) is located.",
    "11. The triple-mode resonator according to claim 10, wherein the input coupling aperture(s) and the output coupling aperture(s) are or are not mirror symmetrical to each other.",
    "12. A waveguide filter, comprising a triple-mode resonator that comprises: a main body made of a dielectric material and having a cuboid shape defining three orthogonal axes (x, y, z) substantially aligned with faces of the main body; and a conductive coating covering all of the main body except portions of the faces of the main body which defines at least one coupling aperture through which a signal can be coupled into and/or out of the main body, wherein the at least one coupling aperture has a closed shape comprising a first and a second main edges extending along two of the axes respectively and a third main edge extending neither parallel nor perpendicular to the first and second main edges, a general shape and size and location of the at least one coupling aperture is mainly determined by the first, second and third main edges, and the at least one coupling aperture is configured in such a manner that desired three dominant resonance modes can be excited independently in the resonator by an input signal introduced therethrough, and wherein the third main edge is in the form of an arc segment.",
    "13. The waveguide filter according to claim 12, wherein the filter further comprises a first single-mode resonator having a main body of a dielectric material and an external conductive coating covering the main body with uncovered portions defining coupling apertures and a second single-mode resonator having a main body of a dielectric material and an external conductive coating covering the main body with uncovered portions defining coupling apertures, and the triple-mode resonator is sandwiched between the first and second single-mode resonators in such a manner that the triple-mode resonator communicates with the first and second single-mode resonators respectively via corresponding coupling apertures on their abutting faces and the desired three dominant resonance modes can be excited in the triple-mode resonator.",
    "14. The waveguide filter according to claim 13, wherein the filter further comprises a third single-mode resonator having a main body of a dielectric material and an external conductive coating covering the main body with uncovered portions defining coupling apertures, and the third single-mode resonator communicates with the first single-mode resonator via corresponding coupling apertures on their abutting faces.",
    "15. The waveguide filter according to claim 14, wherein an output coupling aperture on the third single-mode resonator and an input coupling aperture on the first single-mode resonator are in the form of a circular slot.",
    "16. The waveguide filter according to claim 15, wherein on a face of the third single-mode resonator opposite to the face where its output coupling aperture is located, an input means is connected to the dielectric material in the third single-mode resonator for supplying a signal to be filtered.",
    "17. The waveguide filter according to claim 16, wherein a rotational axis of the input means is coincident with a central axis of circular slots of the third and first single-mode resonators.",
    "18. The waveguide filter according to claim 16, wherein the third main edge of the at least one coupling aperture on the triple-mode resonator is in the form of the arc segment curving towards an inside of the at least one coupling aperture, wherein the arc center of the arc segment is the center of a face where the arc segment is located, and a rotational axis of the input means extends through the arc center of the arc segment."
  ],
  "description_excerpt": "This application is a 35 U.S.C. § 371 national phase filing of International Application No. PCT/CN2020/115656, filed Sep. 16, 2020, the disclosure of which is incorporated herein by reference in its entirety.\n\nThe present disclosure generally relates to the technical field of a filter and, more particularly, to a triple-mode resonator and a waveguide filter comprising the triple-mode resonator.\n\nThis section introduces aspects that may facilitate better understanding of the present disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.\n\nWith the development of 5G communication, the multiple-input and multiple-output (MIMO) technology is widely used in a Sub-6 GHz base station product, which requires a lot of filter units (FUs) to be integrated with an antenna unit (AU) or a radio unit (RU). For saving cost and space, FUs are usually soldered onto a radio mother board, a low pass filter (LPF) board, an antenna calibration (AC) board or a power splitter board, which means smaller and lighter FUs are quite in demand.\n\nIn traditional base stations, metal cavity FUs are widely used because of their high value of Q-factor and power handling performance, but there is still room for improvement in terms of size and weight of a FU for a 5G advanced radio system. A ceramic waveguide (CWG) filter, which is formed from ceramic block coated with conducting material, e.g. silver, is widely used also.",
  "cpc": [
    "H01P 7/105",
    "H01P 1/2086"
  ],
  "assignees": [
    "Telefonaktiebolaget LM Ericsson AB"
  ],
  "inventors": [
    "Honglan WANG",
    "Haitao Liu"
  ],
  "filing_date": "2020-09-16",
  "publication_date": "2025-07-08",
  "grant_date": "2025-07-08",
  "application_number": "US-202018022317-A",
  "family_id": "80775787",
  "cited_by_count": 0,
  "citations": [
    "US20130049899A1",
    "CN104995788A",
    "US20150380794A1",
    "US20150380799A1",
    "US20150180103A1",
    "US20180219268A1",
    "WO2020032939A1",
    "US20210194108A1",
    "WO2020048064A1",
    "CN109273808A"
  ]
}