RF filter for adjusting coupling amount or transmission zero

{
  "publication_number": "US9887442B2",
  "country": "US",
  "kind": "B2",
  "title": "RF filter for adjusting coupling amount or transmission zero",
  "abstract": "An RF filter, e.g. RF cavity filter for adjusting coupling amount or transmission zero is disclosed. The RF filter includes a housing member in which cavities are defined by walls, resonators located in the cavities, a cover combined with an upper surface of the housing member, a first tuning element inserted into a first cavity of the cavities through the cover, and a second tuning element inserted into a second cavity of the cavities through the cover. Here, the first tuning element and the second tuning element are connected electrically.",
  "claims": [
    "1. An RF filter comprising: a housing member; cavities defined by walls in the housing member; resonators located in the cavities; a cover combined with an upper surface of the housing member; a first tuning area formed on one surface of the cover; a second tuning area formed on the one surface of the cover, wherein the second tuning area is separated from the first tuning area; a dielectric area formed between the first tuning area and the second tuning area on the one surface of the cover; a first tuning element inserted into a first cavity of the housing member through the first tuning area of the cover; a second tuning element inserted into a second cavity of the housing member through the second tuning element of the cover; and a tuning sliding member disposed on the one surface of the cover, wherein a coupling window is formed between a part of the cavities, wherein transmission zero or cross coupling amount between the resonators located in a remainder of the cavities in which the coupling window is not formed are varied depending on an overlap area of the tuning sliding member and the dielectric area.",
    "2. The RF filter of claim 1, wherein a first hole and a second hole are formed on a part of the tuning sliding member, the tuning sliding member slides while being supported by the first tuning element through the first hole.",
    "3. The RF filter of claim 1, wherein the tuning sliding member slides while disposed on the first tuning element.",
    "4. The RF filter of claim 1, wherein the cover is formed by coating conductive material on a dielectric member, the first tuning area and the second tuning area are formed by etching a part of the one surface of the cover, and the tuning sliding member is made up of dielectric material.",
    "5. The RF filter of claim 1, wherein at least one of the first tuning element and the second tuning element moves up and down, each of the first tuning element and the second tuning element is a bolt, the first tuning element is fixed to the one surface of the cover by a first nut, and the second tuning element is fixed to the one surface of the cover by a second nut, the first tuning element and the second tuning element are disposed symmetrically with respect to specific wall of the walls."
  ],
  "description_excerpt": "Example embodiment of the present invention relates to an RF filter, e.g. RF cavity filter for adjusting cross-coupling amount or transmission zero.\n\nAn RF cavity filter includes plural cavities formed therein to pass only use frequency band of a signal, and is employed generally at a base station, etc. using comparative high power of a frequency signal.\n\nFIG. 1 is a plan view illustration structure of a common RF cavity filter.\n\nIn FIG. 1, the RF cavity filter includes an input connector 100, an output connector 102, a housing member 104, cavities 110, 112, 114, 116, 118 and 120 defined by the housing member 104 and a wall, resonators 130, 132, 134, 136, 138 and 140 in each of the cavities 110, 112, 114, 116, 118 and 120, and a coupling bar 160.\n\nAn RF signal inputted through the input connector 100 is provided to the cavity 110. Each of the cavities 110, 112, 114, 116, 118 and 120 and corresponding resonators 130, 132, 134, 136, 138 and 140 function as LC resonance elements, respectively.\n\nThe RF signal is delivered from one cavity to another cavity through a coupling window 150.\n\nA resonance frequency of the filter is determined by size of the cavities and size of the resonators. A user may tune finely characteristics of the filter using tuning bolts which are not shown.\n\nThe skirt characteristic which means a slope of a boundary band in a pass band characteristic curve is important in view of the filter, and preferably should be formed sharply.\n\nThe skirt characteristic is improved according as order of the filter increases, i.e. the number of the cavities and the resonators increases.",
  "cpc": [
    "H01P 1/208",
    "H01P 1/2053",
    "H01P 1/2084"
  ],
  "ipc": [
    "H01P 1/20",
    "H01P 1/205",
    "H01P 1/208"
  ],
  "assignees": [
    "Ace Technology Co Ltd"
  ],
  "inventors": [
    "Dong-Yeon Lim",
    "Guy-Yoil YI",
    "Kyung-Min KO",
    "Bong-hoon KIM"
  ],
  "filing_date": "2015-05-11",
  "publication_date": "2018-02-06",
  "grant_date": "2018-02-06",
  "priority_date": "2011-03-31",
  "application_number": "US-201514709354-A",
  "family_id": "46926437",
  "cited_by_count": 3,
  "citations": [
    "US6255917B1",
    "US6559740B1",
    "US20090058563A1",
    "US20110133862A1"
  ]
}