US3882434A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase equalized filter
Assignee: Microwave Development Laboratories Inc
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Filing: 1973-08-01
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Granted: 1975-05-06
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Expires: 1993-08-01
Abstract
Abstract The band-pass filter is constructed from a group of directcoupled resonant elements forming resonant cavities arranged in consecutive order, and at least one alternative path formed by a cross coupling. The filter comprises a first array or series of a plurality of intercoupled resonant cavities having an input end and an output end, and a second array or series of fewer resonant cavities intercoupled with the cavities of the first array. This arrangement provides a band-pass filter having a flat group delay and linear phase over the central portion of the pass band.
Inventors
- 👤 Ralph Levy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:15
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/207; H01P1/208
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
187 words
A microwave band-pass filter having a relatively flat group delay and linear phase over the central portion of the pass-band, said filter comprising; means defining a first series of resonant elements, means for coupling an input signal to a resonant element of the first series, the resonant elements in the first series being each directly coupled in consecutive order with its adjacent element, means defining a second series of resonant elements smaller in number than the number comprising said first series and arranged with each resonant element opposite and in substantial alignment with a different resonant element in the first series, means coupling from a last resonant element in the first series for obtaining an output signal therefrom, the resonant elements in the second series being each directly coupled in consecutive order with its adjacent element, said first and second series being arranged to provide a main path through all of said resonant elements with at least one cross-coupling path being provided between two adjacent elements of the first series, means for independently tuning each resonant element, and tuning means associated with said one extra cross-coupling path.
Claim 2
Dependent Claim
187 words
A microwave band-pass filter having a relatively flat group delay and linear phase over the central portion of the pass-band, said filter comprising; means defining a first series of resonant elements, means for coupling an input signal to a resonant element of the first series, the resonant elements in the first series being each directly coupled in consecutive order with its adjacent element, means defining a second series of resonant elements smaller in number than the number comprising said first series and arranged with each resonant element opposite and in substantial alignment with a different resonant element in the first series, means coupling from a last resonant element in the first series for obtaining an output signal therefrom, the resonant elements in the second series being each directly coupled in consecutive order with its adjacent element, said first and second series being arranged to provide a main path through all of said resonant elements with at least one cross-coupling path being provided between two adjacent elements of the first series, means for independently tuning each resonant element, and tuning means associated with said one extra cross-coupling path.
Claim 3
Dependent Claim
34 words
The filter of claim 1 wherein both the first and second series of resonant elements each include a waveguide structure partitioned by at least one iris-defining means to form a plurality of resonant cavities.
Claim 4
Dependent Claim
27 words
THe filter of claim 2 wherein said waveguide structures have a common wall having means defining at least two coupling apertures between said first and second series.
Claim 5
Dependent Claim
22 words
The filter of claim 1 wherein said second series includes only two resonant elements and there is provided only one cross-coupling path.
Claim 6
Dependent Claim
21 words
The filter of claim 1 characterized by a flat group delay over approximately the center 50 percent of the pass band.
Claim 7
Dependent Claim
13 words
The filter of claim 5 including means for independently tuning each resonant element.
Claim 8
Dependent Claim
151 words
A microwave band-pass filter having a relatively flat group delay and linear phase over the central portion of the pass band, said filter comprising; means defining a series of resonant elements including a waveguide structure partitioned by a plurality of iris-defining means to form a plurality of resonant cavities, said series of resonant elements being arranged so that at least two of said elements are opposite and in substantial alignment with other resonant elements of the series to define a main path through all of the resonant elements, two other of said elements providing one cross-coupling path, means for independently tuning each resonant element, first means for tuning the coupling between the said at least two resonant elements, and second means for tuning the coupling between the said two other resonant elements, said first and second tuning means operable to provide group delay characteristics which are either undercoupled, critically-coupled or over-coupled.
Claim 9
Dependent Claim
151 words
A microwave band-pass filter having a relatively flat group delay and linear phase over the central portion of the pass band, said filter comprising; means defining a series of resonant elements including a waveguide structure partitioned by a plurality of iris-defining means to form a plurality of resonant cavities, said series of resonant elements being arranged so that at least two of said elements are opposite and in substantial alignment with other resonant elements of the series to define a main path through all of the resonant elements, two other of said elements providing one cross-coupling path, means for independently tuning each resonant element, first means for tuning the coupling between the said at least two resonant elements, and second means for tuning the coupling between the said two other resonant elements, said first and second tuning means operable to provide group delay characteristics which are either undercoupled, critically-coupled or over-coupled.
Claim 10
Dependent Claim
13 words
The filter of claim 7 wherein there is provided only one cross-coupling path.
Claim 11
Dependent Claim
22 words
The filter of claim 7 wherein all of said resonant elements are coupled in line except said at least two resonant elements.
Claim 12
Dependent Claim
44 words
The filter of claim 9 wherein a first of said resonant elements of the in line group includes means for receiving an input signal and a last of said resonant elements of the in line group includes means for coupling out an output signal.
Claim 13
Dependent Claim
25 words
The filter of claim 10 wherein said at least two resonant elements are opposite any other resonant elements except said first and last resonant elements.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |