US4465984A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency selective side absorber for a meander line
Assignee: United States Department of the Army
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Filing: 1982-05-10
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Granted: 1984-08-14
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Expires: 2002-05-10
Abstract
Abstract A meander line slow wave structure mounted on ceramic bars for a microwaveevice such as an injected beam crossed-field amplifier includes frequency selective attenuator means which will preferentially attenuate waves at frequencies near and within the stopband of the slow wave structure by the placement of side absorber bars of attenuating material adjacent to the outer side surfaces of a plurality of meander line finger segments. The frequency selective absorber material, in its preferred form, comprises a beryllia and silicon carbide ceramic composition which additionally adapted to accommodate metallic absorber top plates, nichrome films, and slotted side ring configurations.
Inventors
- 👤 Hunter L. McDowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:03
CPC Classifications
H; H01; H01J; H01J23/00; H01J23/16; H01J23/24; H01J23/30
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
129 words
A slow wave structure adapted to selectively attenuate predetermined frequencies in the region of the stopband of said structure, comprising in combination: longitudinal substrate means of dielectric material having an upper conductive surface; a plurality of spaced parallel support members of dielectric material embedded in and extending above and across the width of said substrate means; meander line circuit means including an electrical conductor having spaced parallel conductor members extending across said width and located on said support means and having connecting longitudinal members between alternate ends of said conductor members to form a continuous serpentine pattern; and a plurality of separate spaced parallel attenuator members of dielectric material located on said substrate means between pairs of adjacent support members and spaced from said conductor members and support members.
Claim 2
Dependent Claim
129 words
A slow wave structure adapted to selectively attenuate predetermined frequencies in the region of the stopband of said structure, comprising in combination: longitudinal substrate means of dielectric material having an upper conductive surface; a plurality of spaced parallel support members of dielectric material embedded in and extending above and across the width of said substrate means; meander line circuit means including an electrical conductor having spaced parallel conductor members extending across said width and located on said support means and having connecting longitudinal members between alternate ends of said conductor members to form a continuous serpentine pattern; and a plurality of separate spaced parallel attenuator members of dielectric material located on said substrate means between pairs of adjacent support members and spaced from said conductor members and support members.
Claim 3
Dependent Claim
26 words
The slow wave structure as defined by claim 1 wherein said attenuator members are comprised of a ceramic material different from said substrate and support materials.
Claim 4
Dependent Claim
22 words
The slow wave structure as defined by claim 2 wherein said ceramic material comprises a composition of beryllium oxide and silicon carbide.
Claim 5
Dependent Claim
31 words
The slow wave structure as defined by claim 3 wherein said composition of beryllium oxide and silicon carbide ranges substantially between 40% beryllium oxide and 60% silicon carbide and vice versa.
Claim 6
Dependent Claim
20 words
The slow wave structure as defined by claim 4 wherein said composition comprises 40% beryllium oxide and 60% silicon carbide.
Claim 7
Dependent Claim
20 words
The slow wave structure as defined by claim 2 wherein said ceramic material comprises a carbon loaded porous alumina composition.
Claim 8
Dependent Claim
26 words
The slow wave structure as defined by claim 2 wherein said support means comprises a plurality of ceramic support elements underlying said meander line circuit means.
Claim 9
Dependent Claim
19 words
The slow wave structure as defined by claim 7 wherein said ceramic support elements are comprised of beryllium oxide.
Claim 10
Dependent Claim
64 words
The slow wave structure as defined by claim 2 wherein said serpentine conductor pattern is comprised of a plurality of elongated conductor segments connected in series by a plurality of relatively shorter conductor segments forming a composite structure thereby and wherein said attenuator members comprises a plurality of elongated bars of ceramic material located intermediate adjacent pairs of said plurality of elongated conductor segments.
Claim 11
Dependent Claim
38 words
The slow wave structure as defined by claim 9 wherein said elongated bars are generally rectangular in cross section and having a respective upper surface which is located below the upper surface of the adjacent elongated conductor segments.
Claim 12
Dependent Claim
37 words
The slow wave structure as defined by claim 9 wherein said elongated bars of ceramic material are generally rectangular in cross section and having a respective upper surface which additionally includes a metallic conductor plate formed thereon.
Claim 13
Dependent Claim
36 words
The slow wave structure as defined by claim 9 wherein said elongated bars of ceramic material are generally rectangular in cross section and having a respective upper surface which additionally includes a resistive film formed thereon.
Claim 14
Dependent Claim
17 words
The slow wave structure as defined by claim 12 wherein said resistive film is comprised of nichrome.
Claim 15
Dependent Claim
38 words
The slow wave structure as defined by claim 12 wherein said elongated bars additionally include a pair of opposing side surfaces having a plurality of shunt resistive strips formed thereon between said resistive film and said substrate means.
Claim 16
Dependent Claim
31 words
The slow wave structure as defined by claim 14 wherein said shunt resistive strips are mutually separated by one half wavelength at the band edge frequency where selective attenuation is desired.
Claim 17
Dependent Claim
21 words
The slow wave structure as defined by claim 14 wherein said resistive film and said shunt strips are comprised of nichrome.
Claim 18
Dependent Claim
45 words
The slow wave structure as defined by claim 10 and additionally including a slotted side slide ring member located contiguous to said bars and extending upwards toward the upper surface of said conductor segments and including a plurality of slots spanning pairs of conductor segments.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-14 | 1988-02-13 | 1988-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-14 | 1992-02-13 | 1992-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-14 | 1996-02-13 | 1996-08-14 | $7700.00 | Window Closed / Lapsed |