Tunable dual-band band-pass filter

Patent metadata

Field	Value
Publication number	US-9979064-B2
Application number	US-201514808183-A
Country	US
Kind code	B2
Filing date	Jul 24, 2015
Priority date	Dec 9, 2014
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A tunable dual-band resonator and a tunable dual-band band-pass filter using the tunable dual-band resonator. The dual-band resonator is structured such that a stub is added to each half-wavelength resonator provided with half-wavelength resonator protrusions (capacity-component adjust parts). The dual-band resonator is made up of an odd-number mode resonator in a shape including a ground conductor disposed on the back surface of a dielectric body, and a strip conductor disposed on the top surface thereof, and an even-number mode resonator in such a shape as to be formed when the stub is connected to an end face on the opposite side of the open-end of the strip, characterized in that a dielectric rod having a circular cross section is provided in the space above the respective stubs and another dielectric rod having a circular cross section is provided in the space above the half-wavelength resonator protrusions.

First claim

The invention claimed is:

1. A tunable dual-band resonator structured such that a stub is added to a half-wavelength resonator provided with half-wavelength resonator protrusions; wherein symmetric planes of the stub function as an electrical and a magnetic wall, respectively; the tunable dual-band resonator operating in two frequency-bands due to a resonance in an odd-number mode and a resonance in an even-number mode, and being capable of adjusting a resonator length such that the half-wavelength resonator operates in the odd-number mode, while the half-wavelength resonator and the stub operate in the even-number mode, thereby causing the odd-number mode to resonate on a low-frequency side, while causing the even-number mode to resonate on a high-frequency side, or alternatively, enabling the odd-number mode to resonate on the high-frequency side, while enabling the even-number mode to resonate on the low-frequency side;
said when operating in the odd-number mode, tunable dual-band resonator is made up of
an odd-number mode resonator in a shape including a ground conductor in a predetermined thickness disposed on the back surface of a dielectric body, and a strip conductor disposed on the top surface thereof, the strip conductor having an open-end thereof being provided with a deeply retreated groove having a width g, the strip conductor having a width d at a tip of the groove and at an end face of the strip conductor; and
when operating in the even-number mode, said tunable dual-band resonator is made up of an even-number mode resonator being in such a shape as to be formed when the stub having a length 1 is connected to the end face of the strip conductor which is on an opposite side of the open-end of the strip conductor;
wherein the tunable dual-band resonator operates as the odd-number mode resonator when an electric current flows to the symmetric planes of the stub, and operates as the even-number mode resonator when the electric current does not flow to the symmetric planes;
characterized in that a dielectric rod having a circular cross section is provided in a space above the stub, and the dielectric rod is provided in a space above the half-wavelength resonator protrusions of the half-wavelength resonator, thereby enabling a resonance frequency in the even-number mode, and a resonance frequency in the odd-number mode, to be tuned independently from each other.

Assignees

• Univ Yamanashi
• Japan Steel Works Ltd

Inventors

• Sekiya Naoto
• Terao Katsuhiro
• Kishida Kazuhito
• Sato Yasuo
• Kitada Noritaka

Classifications

• H01P7/105

  Multimode resonators · CPC title

• H01P7/088

  Tunable resonators · CPC title

• H01P7/082

  Microstripline resonators (H01P7/088 takes precedence) · CPC title

• H01P1/20372 Primary

  Hairpin resonators · CPC title

• H01P1/20309 Primary

  with dielectric resonator · CPC title