Resonant wave filter

• US 4,837,535 A
• Filed: 01/05/1989
• Issued: 06/06/1989
• Est. Priority Date: 01/05/1989
• Status: Expired due to Fees

• Current Assignee: Uniden Corporation (Cornwall Capital Management LP)
• Original Assignee: Uniden Corporation (Cornwall Capital Management LP)
• Inventors: Konishi, Yoshihiro, Konno, Kenichi, Awai, Ikuo
• Primary Examiner(s): Nussbaum, Marvin L.
• Application Number:
  US07/293,666
• Time in Patent Office: 152 Days
• Field of Search: 333/202, 333/206-212, 333/245, 333/248, 333/134-136, 333/219, 333/219.1, 333/222-233
• US Class Current: 333/210
• CPC Class Codes: H01P 1/2056 Comb filters or interdigital filters with metallised resonator holes in a dielectric block
• CPC Class Codes: H01P 1/208 Cascaded cavities; Cascaded resonators inside a hollow waveguide structure H01P1/205 takes precedence
• CPC Class Codes: H01P 1/2088 Integrated in a substrate
• CPC Class Codes: H01P 1/219 Evanescent mode filters

Abstract

A compact resonant wave filter capable of selectively propagating an electromagnetic wave of a prescribed frequency with excellent band-pass wave filter characteristics comprises a TM mode resonator disposed perpendicularly to the direction of propagation of electromagnetic wave energy, a pair of TEM mode resonators disposed one on either side or said TM mode resonator in the direction of propagation of electromagnetic wave energy, and a pair of cutoff waveguides disposed one between said TEM mode resonator and each of said TM mode resonators to couple said TEM mode resonator with said TM mode resonators in evanescent mode.

Claims

1. A resonant wave filter capable of selectively propagating an electromagnetic wave of a prescribed frequency comprising a TM mode resonator disposed perpendicularly to the direction of propagation of electromagnetic wave energy, a pair of TEM mode resonators disposed one on either side or said TM mode resonator in the direction of propagation of electromagnetic wave energy, and a pair of cutoff waveguides disposed one between said TEM mode resonator and each of said TM mode resonators to couple said TEM mode resonator with said TM mode resonators in evanescent mode.

2. A resonant wave filter according to claim 1 wherein said TM mode resonator is a waveguide resonator.

3. A resonant wave filter according to claim 1 wherein said TM mode resonator is a plurality of waveguide resonators.

4. A resonant wave filter according to claim 1 wherein said TEM mode resonator is a coaxial resonator.

5. A resonant wave filter according to claim 1 wherein said TEM mode resonator is a plurality of coaxial resonators.

6. A resonant wave filter according to claim 2 wherein the interior of said waveguide resonator is filled with a dielectric.

7. A resonant wave filter according to claim 4 wherein the interior of said coaxial resonator is filled with a dielectric.

8. A resonant wave filter according to claim 1 wherein the interior of said cutoff waveguide is filled with a dielectric.