US4431999A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interference cancelling system using a notch and omnidirectional antenna
Assignee: United States Department of the Army
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Filing: 1982-07-08
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Granted: 1984-02-14
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Expires: 2002-07-08
Abstract
Abstract The described system utilizes a pair of antenna beam patterns, one of whichs adapted to provide the desired signal and all interfering signals, and the other of which is adapted to provide only the interfering signals. The patterns are then combined to produce substantially only the desired signal as the combined output.
Inventors
- 👤 Frank S. Gutleber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:10
CPC Classifications
H; H01; H01Q; H01Q3/00; H01Q3/26; H01Q3/2605; H01Q3/2611; H01Q3/2629
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
86 words
A method of cancelling interference in a communication system comprising: receiving signals from substantially all directions on an omnidirectional antenna means; receiving coherent and correlated signals from substantially all directions except in the direction of a desired signal on a directable notch antenna means; adjusting the amplitude and phase of said signals received by said notch antenna means to match said signals received by said omnidirectional antenna means; and subtracting signals received on said directable notch antenna means from signals received on said omnidirectional antenna means.
Claim 2
Independent Claim
86 words
A method of cancelling interference in a communication system comprising: receiving signals from substantially all directions on an omnidirectional antenna means; receiving coherent and correlated signals from substantially all directions except in the direction of a desired signal on a directable notch antenna means; adjusting the amplitude and phase of said signals received by said notch antenna means to match said signals received by said omnidirectional antenna means; and subtracting signals received on said directable notch antenna means from signals received on said omnidirectional antenna means.
Claim 3
Dependent Claim
111 words
An interference cancelling communication system comprising: an omnidirectional antenna means, having gain in all directions, for providing a first output signal including a desired signal and all interfering signals; a directional notch antenna means, having substantially the same gain as said omnidirectional antenna means in substantially all of said directions except for a relatively steep, narrow null sector, for providing a second output signal which is coherent and correlated with said first output signal except for signals arriving in the direction of said null sector; means connected to the output of said omnidirectional antenna means and said notch antenna means for subtracting said second output signal from said first output signal.
Claim 4
Dependent Claim
111 words
An interference cancelling communication system comprising: an omnidirectional antenna means, having gain in all directions, for providing a first output signal including a desired signal and all interfering signals; a directional notch antenna means, having substantially the same gain as said omnidirectional antenna means in substantially all of said directions except for a relatively steep, narrow null sector, for providing a second output signal which is coherent and correlated with said first output signal except for signals arriving in the direction of said null sector; means connected to the output of said omnidirectional antenna means and said notch antenna means for subtracting said second output signal from said first output signal.
Claim 5
Dependent Claim
22 words
The system of claim 2 wherein said omnidirectional antenna means and said notch antenna means have a common center axis of radiation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-13 | 1987-08-15 | 1988-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-13 | 1991-08-15 | 1992-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-13 | 1995-08-15 | 1996-02-14 | $7700.00 | Window Closed / Lapsed |