US5142292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coplanar multiple loop antenna for electronic article surveillance systems
Assignee: Checkpoint Systems Inc
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Filing: 1991-08-05
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Granted: 1992-08-25
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Expires: 2011-08-05
Abstract
Abstract An antenna for transmitting electromagnetic energy for deactivating a resonant tag circuit of an electronic article surveillance tag without regard to the orientation of the tag while minimizing far field radiation. The antenna includes a substantially planar dielectric substrate having a first side and a second side. The antenna also includes four substantially coplanar conductive loops on the first side of the dielectric substrate. The conductive loops are arranged in a two-by-two sequence and connected in series such that current flowing through any one of the conductive loops is out of phase with respect to current flowing in each adjacent conductive loop. The antenna also includes a ground trace on the second side of the substrate.
Inventors
- 👤 Luke C. Chang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:04
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2414; G08B13/242; H; H01; H01Q; H01Q11/00; H01Q11/12; H01Q7/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
An antenna for transmitting electromagnetic energy for deactivating a resonant circuit of an electronic article surveillance tag without regard to the orientation of the tag while minimizing far field radiation, comprising: a substantially planar dielectric substrate having a first side and a second side; four substantially coplanar conductive loops on the first side of the dielectric substrate, the conductive loops being arranged in a two-by-two sequence and connected in series such that current flowing through any one of the conductive loops is out of phase with respect to current flowing in each adjacent conductive loop; and a ground trace on the second side of the substrate.
Claim 2
Dependent Claim
106 words
An antenna for transmitting electromagnetic energy for deactivating a resonant circuit of an electronic article surveillance tag without regard to the orientation of the tag while minimizing far field radiation, comprising: a substantially planar dielectric substrate having a first side and a second side; four substantially coplanar conductive loops on the first side of the dielectric substrate, the conductive loops being arranged in a two-by-two sequence and connected in series such that current flowing through any one of the conductive loops is out of phase with respect to current flowing in each adjacent conductive loop; and a ground trace on the second side of the substrate.
Claim 3
Dependent Claim
26 words
An antenna according to claim 1, wherein the dielectric substrate comprises a printed circuit board and the conductive loops are etched onto the printed circuit board.
Claim 4
Dependent Claim
23 words
An antenna according to claim 1, wherein each conductive loop comprises a printed circuit track of predetermined width which defines a loop boundary.
Claim 5
Dependent Claim
21 words
An antenna according to claim 3, wherein the area defined by the boundary of each of the loops is generally equal.
Claim 6
Dependent Claim
24 words
An antenna according to claim 3, wherein the ground trace substantially underlies each loop printed circuit track and a portion of each loop area.
Claim 7
Dependent Claim
14 words
An antenna according to claim 1, wherein each loop has a generally square configuration.
Claim 8
Dependent Claim
40 words
An antenna according to claim 1, wherein the loops are connected in series such that the current in each loop flows in a first direction which is opposite to a second direction in which current flows in each adjacent loop.
Claim 9
Dependent Claim
14 words
An antenna according to claim 1, wherein the conductive loops are formed of copper.
Claim 10
Dependent Claim
14 words
An antenna according to claim 1, wherein the ground trace is formed of copper.
References Cited (Backward Citations)
US3665449A
Cited
US4016553A
Cited
US4118693A
Cited
US4251808A
Cited
US4373163A
Cited
US4498076A
Cited
US4633250A
Cited
US4866455A
Cited
US4845509A
Cited
US4782342A
Cited
US4864280A
Cited
US4872018A
Cited
US4999641A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-25 | 1996-02-24 | 1996-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-25 | 2000-02-24 | 2000-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-25 | 2004-02-24 | 2004-08-25 | $7700.00 | Window Closed / Lapsed |