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US4200847A Expired / Lapsed US ⏱️ 0.0 years remaining

Rectangular branching filter having plurality of rod members for fine impedance matching

Assignee: Murata Manufacturing Co Ltd
•
Filing: 1977-09-26
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Granted: 1980-04-29
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Expires: 1997-09-26
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Abstract

Abstract A T-shaped rectangular waveguide branching filter includes an electrically conductive projection or protrusion of approximately triangular cross section which is formed at a predetermined portion within the branching filter for preliminary impedance matching of a predetermined accuracy as observed from each of the input/output ports of the branching filter, and an electrically conductive rod which may be selectively advanced toward or retracted from the first input/output port and extends through the electrically conductive protrusion of triangular cross section so that, by selectively advancing or retracting the conductive rod, a particular impedance match corresponding to each of the input/output ports as observed from any one of the input/output ports may be achieved for efficiently deriving the signal applied to one of the input/output ports from either one of the other input/output ports.

Inventors

  • 👤 Toshio Nishikawa
  • 👤 Yoji Ito
  • 👤 Youhei Ishikawa
  • 👤 Sadahiro Tamura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 21:49
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/213; H01P1/2138

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 193 words
A T-shape rectangular waveguide branching filter comprising: a main structure having first, second and third input/output ports, a first rectangular waveguide section connecting said second and third input/output ports in a straight line and a second rectangular waveguide section connected to said first input/output port and intersecting said first rectangular waveguide section at a right angle; a protrusion of an electrically conducting material having a triangular cross section, said protrusion aligned perpendicular to the plane of the longitudinal axes of said first and second rectangular waveguide sections and disposed within said main structure at a central portion of the wall of said first rectangular waveguide section opposite the intersection with said second rectangular waveguide section for confronting said first input/output port and for preliminary impedance matching of a predetermined accuracy with respect to said first, second and third input/output ports; and a plurality of rod members of electrically conductive material extending through said protrusion to project from the apex portion of said protrusion toward said first input/output port for selective movement toward and away from said first input/output port for fine impedance matching with respect to said first, second and third input/output ports.
Claim 2
Dependent Claim 193 words
A T-shape rectangular waveguide branching filter comprising: a main structure having first, second and third input/output ports, a first rectangular waveguide section connecting said second and third input/output ports in a straight line and a second rectangular waveguide section connected to said first input/output port and intersecting said first rectangular waveguide section at a right angle; a protrusion of an electrically conducting material having a triangular cross section, said protrusion aligned perpendicular to the plane of the longitudinal axes of said first and second rectangular waveguide sections and disposed within said main structure at a central portion of the wall of said first rectangular waveguide section opposite the intersection with said second rectangular waveguide section for confronting said first input/output port and for preliminary impedance matching of a predetermined accuracy with respect to said first, second and third input/output ports; and a plurality of rod members of electrically conductive material extending through said protrusion to project from the apex portion of said protrusion toward said first input/output port for selective movement toward and away from said first input/output port for fine impedance matching with respect to said first, second and third input/output ports.

References Cited (Backward Citations)

US2590373A Cited
US2584162A Cited
US2801390A Cited
GB870873A Cited
US3493896A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-04-29 1983-10-29 1984-04-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-04-29 1987-10-29 1988-04-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-04-29 1991-10-29 1992-04-29 $7700.00 Window Closed / Lapsed

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