Claims
- 1. A resonator configured to resonate in the TE0γδ mode at a lowest resonant frequency having a wavelength λ in empty space, said resonator comprising:a dielectric resonator disk configured to exhibit an effective dielectric constant εre, said disk having first and second opposing ends along an axis and a closed curve wall surrounding said axis and extending between said first and second ends, said disk having a hole penetrating therein from said first end and extending toward said second end, wherein at least one of said first and second ends serves as a boundary between said disk and a dielectric material having a dielectric constant less than 0.5εre; and a conductive wall juxtaposed with said curved wall of said disk and positioned less than 0.75λ/{square root over (εre)} from said axis.
- 2. A resonator as claimed in claim 1 wherein:said hole extends through said disk from said first end to said second end; said disk is shaped as a cylinder having a diameter D; and said hole exhibits a diameter greater than 0.1D.
- 3. A resonator as claimed in claim 2 wherein said hole exhibits a diameter greater than 0.21D.
- 4. A resonator as claimed in claim 3 wherein said hole exhibits a diameter less than 0.4D.
- 5. A resonator as claimed in claim 1 wherein said dielectric material having a dielectric constant less than 0.5εre extends away from said boundary for a distance of at least 0.25λ/{square root over (εre)}.
- 6. A resonator as claimed in claim 1 wherein no conductive wall is positioned closer than 0.25λ/{square root over (εre)} from said first or second ends of said disk.
- 7. A resonator as claimed in claim 1 wherein said conductive wall is positioned less than 0.6 λ/{square root over (εre)} from said axis.
- 8. A resonator as claimed in claim 1 wherein said disk has an axial length of less than 0.5λ/{square root over (εre)}.
- 9. A resonator as claimed in claim 1 wherein said disk is comprised of first and second rings which exhibit different dielectric constants and different quality factors (Q).
- 10. A resonator as claimed in claim 9 wherein:said first ring is concentric with and resides outside of said second ring; said first and second rings each have inside and outside diameters; and the ratio of said inside diameter of said first ring to said outside diameter of said first ring is less than the ratio of said inside diameter of said second ring to said outside diameter of said second ring.
- 11. A resonator as claimed in claim 9 wherein:said first ring resides outside of said second ring; and said first ring exhibits a higher dielectric constant than said second ring.
- 12. A resonator as claimed in claim 9 wherein said disk additionally comprises a third ring which exhibits a different dielectric constant and quality factor (Q) from the dielectric constants and quality factors (Q) of said first and second rings.
- 13. A resonator as claimed in claim 9 wherein:said first ring is concentric with and resides outside of said second ring; an inter-ring gap exists between said first and second rings; and said inter-ring gap is occupied by a dielectric material having a dielectric constant<0.5εre.
- 14. A resonator configured to resonate in the TE0γδ mode at a lowest resonant frequency having a wavelength λ in empty space, said resonator comprising:a composite dielectric disk having first and second dielectric rings which have a common axis with said first ring being located outside said second ring, said first dielectric ring exhibiting a greater dielectric constant than said second ring and said first and second rings collectively exhibiting an effective dielectric constant εre, said first ring having an outside diameter D, and said second ring having an axially aligned interior hole occupied by a material exhibiting a dielectric constant less than 0.5εre and exhibiting a diameter greater than or equal to 0.21D but less than or equal to 0.4D; and a conductive wall circumferentially surrounding said composite dielectric disk and positioned less than 0.75λ/{square root over (εre)} from said axis.
- 15. A resonatorhaving a lowest resonant frequency with a wavelength λ in empty space and an effective dielectric constant εre, said resonator comprising: a first dielectric resonator disk formed from a first material which exhibits a first dielectric constant and a first quality factor (Q), having a hole therein, and having a closed curve wall surrounding an axis of said first disk; a conductive wall surrounding said first disk and positioned less than 0.75λ/{square root over (εre)} from said axis; and a second dielectric resonator disk located inside said hole of said first dielectric resonator disk, said second disk being formed from a second material which exhibits a second dielectric constant and a second quality factor (Q).
- 16. A resonator as claimed in claim 15 wherein:said first disk has an outside diameter D; and said second disk has an axially aligned hole therein, said second disk hole being occupied by a material exhibiting a dielectric constant less than 0.5εre and exhibiting a diameter greater than or equal to 0.21D but less than or equal to 0.4D.
- 17. A resonator as claimed in claim 15 wherein each of said first and second disks has an axial length of less than 0.5λ/{square root over (εre)}.
- 18. A resonator comprising:a first dielectric resonator disk having a hole therein, said first disk being formed from a first material which exhibits a first dielectric constant and a first quality factor (Q); a second dielectric resonator disk having a hole therein and located inside said hole of said first dielectric resonator disk, said second disk being formed from a second material which exhibits a second dielectric constant and a second quality factor (Q); and a third dielectric resonator disk positioned inside said hole of said second disk, said second disk exhibiting a higher dielectric constant than said third disk.
- 19. A resonator as claimed in claim 18 wherein:said first disk exhibits a dielectric constant greater than 40; and said second disk exhibits a dielectric constant less than 40.
- 20. A resonator comprising:a first dielectric resonator disk having a hole therein, said first disk being formed from a first material which exhibits a first dielectric constant and a first quality factor (Q); a second dielectric resonator disk located inside said hole of and concentric with said first disk, said second disk having a hole therein and being formed from a second material which exhibits a second dielectric constant and a second quality factor (Q); said first and second disks each have inside and outside diameters; and the ratio of said inside diameter of said first disk to said outside diameter of said first disk is less than the ratio of said inside diameter of said second disk to said outside diameter of said second disk.
- 21. A resonator comprising:a first dielectric resonator disk having a hole therein, said first disk being formed from a first material which exhibits a first dielectric constant and a first quality factor (Q); a second dielectric resonator disk having a hole therein and located inside said hole of said first dielectric resonator disk, said second disk being formed from a second material which exhibits a second dielectric constant and a second quality factor (Q); and a third dielectric resonator disk located within said hole of said second disk, said third disk exhibiting a different dielectric constant and quality factor (Q) from the dielectric constants and quality factors (Q) of said first and second disks.
RELATED INVENTION
The present invention is a continuation in part (CIP) of “TE0γδ MODE DIELECTRIC RESONATOR,” U.S. patent application Ser. No. 09/099,621, filed June 18, 1998, now abandoned, which is incorporated by reference herein.
US Referenced Citations (9)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0 492 304 A1 |
Jul 1992 |
EP |
60-98703 |
Jun 1985 |
JP |
Non-Patent Literature Citations (2)
Entry |
Cheng-Chyi You, Chen-Liang Huang and Chung-Chuang Wei, “Single-Block Ceramic Microwave Bandpass Filters”, The Microwave Journal, Nov. 1994, pp. 24-35. |
Trans-Tech, Inc., “Dielectric Resonators and Related Products—A Designer's Guide to Microwave Dielectric Ceramics”, Apr. 1993. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/099621 |
Jun 1998 |
US |
Child |
09/215856 |
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US |