US3801976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission line presence sensor
Assignee: Unisys Corp
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Filing: 1971-12-06
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Granted: 1974-04-02
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Expires: 1991-12-06
Abstract
Abstract A high frequency generator-receiver system for detecting the presence or proximity of objects including persons or vehicles employs continuous wave transmission of high frequency electromagnetic signals and reception thereof with respect to a transmission line energy coupling system by a receiver circuit cooperating with the transmission line coupling system for detecting changes in the coupled signal energy and for providing corresponding outputs suitable for indication or other reaction to the presence of such proximate objects.
Inventors
- 👤 G Ross
- 👤 Lorenzo J De
- 👤 D Lamensdorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:21
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/01; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
In combination: a passageway surface means having a principal direction of passage, dielectric substrate means having surface means substantially coplanar with said passageway surface means, signal generator means for supplying continuous wave signals, transmission line energy coupling means excited by said continuous wave signals comprising first and second transmission line conductor means of finite length spaced apart in substantially parallel energy coupling relation on said substrate surface and lying substantially transverse of said principal direction, said coupling means having a predetermined coupling characteristic alterable according to the proximity of an object overlying at least a portion of said coupling means, receiver means for receiving presence detection signals in response to changes in said coupling characteristic, threshold detector means responsive to said receiver means for providing an output signal for signals generated by said receiver means of amplitude greater than a predetermined amplitude, and utilization means responsive to said threshold detector means.
Claim 2
Dependent Claim
151 words
In combination: a passageway surface means having a principal direction of passage, dielectric substrate means having surface means substantially coplanar with said passageway surface means, signal generator means for supplying continuous wave signals, transmission line energy coupling means excited by said continuous wave signals comprising first and second transmission line conductor means of finite length spaced apart in substantially parallel energy coupling relation on said substrate surface and lying substantially transverse of said principal direction, said coupling means having a predetermined coupling characteristic alterable according to the proximity of an object overlying at least a portion of said coupling means, receiver means for receiving presence detection signals in response to changes in said coupling characteristic, threshold detector means responsive to said receiver means for providing an output signal for signals generated by said receiver means of amplitude greater than a predetermined amplitude, and utilization means responsive to said threshold detector means.
Claim 3
Dependent Claim
129 words
Transmission line energy coupling object presence detector means having a predetermined high-frequency energy coupling characteristic comprising: dielectric substrate means having surface means adapted to be placed in substantially coplanar relation with passageway surface means, first and second substantially parallel energy coupling planar transmission line conductor means at said dielectric surface means for defining a coupling region, said coupling region having a length D equal to lambda o/2, where lambda o is the preferred operating high frequency wave length for said coupling means, said substrate means and said conductor means being so constructed and arranged as to respond to said object when overlying at least a portion of said coupling means by a change in the degree of energy coupling between said conductor means, and means responsive to said change.
Claim 4
Dependent Claim
129 words
Transmission line energy coupling object presence detector means having a predetermined high-frequency energy coupling characteristic comprising: dielectric substrate means having surface means adapted to be placed in substantially coplanar relation with passageway surface means, first and second substantially parallel energy coupling planar transmission line conductor means at said dielectric surface means for defining a coupling region, said coupling region having a length D equal to lambda o/2, where lambda o is the preferred operating high frequency wave length for said coupling means, said substrate means and said conductor means being so constructed and arranged as to respond to said object when overlying at least a portion of said coupling means by a change in the degree of energy coupling between said conductor means, and means responsive to said change.
Claim 5
Dependent Claim
21 words
Apparatus as described in claim 2 wherein said dielectric substrate means is placed within a recess in said passageway surface means.
Claim 6
Dependent Claim
20 words
Apparatus as described in claim 2 wherein said substrate means surface means includes a recessed portion between said conductor means.
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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) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |