Patent US3587008A successfully refreshed from Google Patents.
US3587008A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave narrow band-pass filter
Assignee: Raytheon Co
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Filing: 1968-06-24
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Granted: 1971-06-22
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Expires: 1988-06-24
Abstract
Abstract A very narrow band-pass microwave filter is described. Narrow bandwidth operation with low passband insertion loss is achieved by utilizing a cascaded combination of two band-pass filters coincidentally tuned in a unique manner. By providing independent adjustment of the two constituent filters of the cascaded combination arbitrarily narrow passband can be obtained over the operating frequency range.
Inventors
- 👤 George I Tsuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:52
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/207; H01P1/208
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
89 words
A narrow-band band-pass filter comprising, in combination: a first coupled-cavity resonator filter section having a substantially flat band-pass response over a first frequency range; a second coupled-cavity filter section having a substantially flat band-pass response over a second frequency range; said first and second frequency ranges being coextensive over a third frequency range, said third frequency range being substantially less than either said first or second frequency ranges; and means for electromagnetically coupling said first and second filter sections in cascade between an input port and an output port.
Claim 2
Dependent Claim
89 words
A narrow-band band-pass filter comprising, in combination: a first coupled-cavity resonator filter section having a substantially flat band-pass response over a first frequency range; a second coupled-cavity filter section having a substantially flat band-pass response over a second frequency range; said first and second frequency ranges being coextensive over a third frequency range, said third frequency range being substantially less than either said first or second frequency ranges; and means for electromagnetically coupling said first and second filter sections in cascade between an input port and an output port.
Claim 3
Dependent Claim
16 words
The band-pass filter according to claim 1 wherein said coupling means comprises a waveguide matching section.
Claim 4
Dependent Claim
30 words
The band-pass filter according to claim 2 wherein said matching section has a length substantially equal to the average length of the cavities of said first and second filter sections.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |