US3745489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave and uhf filters using discrete hairpin resonators
Assignee: SRI International Inc
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Filing: 1972-05-01
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Granted: 1973-07-10
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Expires: 1992-05-01
Abstract
Abstract A new class of microwave and UHF filters is disclosed using only discrete hairpin resonators, with input and output lines either open circuited or short circuited at their ends, or using both discrete hairpin resonators and half-wave parallel-coupled line filter structures in hybrid filter configurations.
Inventors
- 👤 E Cristal
- 👤 S Frankel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:49
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/201; H01P1/203; H01P1/20327; H01P1/20336; H01P1/20354; H01P1/20372
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
119 words
A structure selected from stripline or microwave-integratedcircuit forms for use as a finite filter comprised of: a plurality of half-wave, parallel-coupled and open-circuited resonators disposed in parallel in an array, at least one of said resonators being folded at the center to form a discrete hairpin resonator, each of said resonators having negligible coupling to all other resonators in said array excepting immediately adjacent resonators and the end of each resonator being opposite the center of adjacent resonators in said array and unconnected to any other resonator; an input line parallel to one of said resonators at one end of said array; and an output line parallel to one of said resonators at the other end of said array.
Claim 2
Dependent Claim
119 words
A structure selected from stripline or microwave-integratedcircuit forms for use as a finite filter comprised of: a plurality of half-wave, parallel-coupled and open-circuited resonators disposed in parallel in an array, at least one of said resonators being folded at the center to form a discrete hairpin resonator, each of said resonators having negligible coupling to all other resonators in said array excepting immediately adjacent resonators and the end of each resonator being opposite the center of adjacent resonators in said array and unconnected to any other resonator; an input line parallel to one of said resonators at one end of said array; and an output line parallel to one of said resonators at the other end of said array.
Claim 3
Dependent Claim
18 words
A structure as defined in claim 1 wherein each of said input and output lines is open circuited.
Claim 4
Dependent Claim
18 words
A structure as defined in claim 1 wherein each of said input and output lines is short circuited.
Claim 5
Dependent Claim
28 words
A structure as defined in claim 1 wherein only some of said resonators are folded at the center to form a hybrid array of hairpin and half-wave resonators.
Claim 6
Dependent Claim
29 words
A structure as defined in claim 1 wherein all of said resonators are half-wave parallel-coupled open circuited resonators folded at the center to form an array of hairpin resonators.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |