US5432518A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Closed slot antenna having outer and inner magnetic loops
Assignee: Texas Instruments Inc
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Filing: 1993-06-15
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Granted: 1995-07-11
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Expires: 2013-06-15
Abstract
Abstract An RF identification system having an interrogator operable to send RF interrogations to a transponder and to receive RF responses from the transponder. The interrogator is in electrical communication with a closed slot antenna. The closed slot antenna is formed by an an outer virtual magnetic loop and an inner virtual magnetic loop such that the antenna has a superior magnetic field when compared to a balanced double loop antenna with an equal area and a superior far-field noise suppression when compared to the single loop antenna. The antenna receives said RF responses from the transponder and provides said RF responses to said interrogator. Other devices, systems and methods are also disclosed.
Inventors
- 👤 Cornelis M. J. van Erven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:23
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/2208; H01Q1/2241; B; B60; B60C; B60C23/00; B60C23/02; B60C23/04; B60C23/0408; B60C23/0422; B60C23/0433; B60C23/0447; B60C23/0452; B60C23/0491; B60C23/0493; G; G01; G01S; G01S13/00; G01S13/74; G01S13/75; G06; G06K; G06K19/00; G06K19/06; G06K19/067; G06K19/07; G06K19/077; G06K19/07749; G06K19/07758; G06K19/07764; G06K7/00; G06K7/0008; G06K7/10; G06K7/10009; G06K7/10316; G06K7/10336; H01Q13/00; H01Q13/10; H01Q7/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
94 words
An RF identification system, said system comprising: a) an interrogator operable to send RF interrogations and to receive RF responses; b) a closed slot antenna in electrical communication with said interrogator, said antenna comprising an an outer virtual magnetic loop and an inner virtual magnetic loop, said antenna operable to receive said RF responses and to provide said RF responses to said interrogator; and c) a transponder associated with an object to be identified, said transponder operable to receive said RF interrogations and to provide said RF responses in response to said RF interrogations.
Claim 2
Dependent Claim
94 words
An RF identification system, said system comprising: a) an interrogator operable to send RF interrogations and to receive RF responses; b) a closed slot antenna in electrical communication with said interrogator, said antenna comprising an an outer virtual magnetic loop and an inner virtual magnetic loop, said antenna operable to receive said RF responses and to provide said RF responses to said interrogator; and c) a transponder associated with an object to be identified, said transponder operable to receive said RF interrogations and to provide said RF responses in response to said RF interrogations.
Claim 3
Dependent Claim
32 words
The RF identification system of claim 1 wherein said closed slot antenna is further operable to receive said RF interrogations from said interrogator and to transmit said RF interrogations to said transponder.
Claim 4
Dependent Claim
23 words
The RF identification system of claim 1 wherein said interrogator is further operable to send WRITE data to said transponder for storage therein.
Claim 5
Dependent Claim
28 words
The RF identification system of claim 1 wherein said transponder is further operable to transmit said WRITE data to another interrogator in response to an RF interrogation therefrom.
Claim 6
Dependent Claim
28 words
The RF identification system of claim 1 wherein said transponder is further operable to transmit said WRITE data to said interrogator in response to said RF interrogation therefrom.
Claim 7
Dependent Claim
16 words
The RF identification system of claim 1 wherein said object to be identified is a tire.
Claim 8
Dependent Claim
28 words
The RF identification system of claim 6 wherein said interrogator and said antenna are located within a housing upon which said tire may be placed for interrogation thereof.
Claim 9
Dependent Claim
28 words
The RF identification system of claim 7 wherein said tire and said antenna are in proximity to each other and said tire is approximately concentric with said antenna.
Claim 10
Dependent Claim
14 words
The RF identification system of claim 1 where said closed slot antenna is circular.
Claim 11
Dependent Claim
14 words
The RF identification system of claim 1 wherein said closed slot antenna is rectangular.
Claim 12
Independent Claim
132 words
A method of identifying objects, the method comprising the steps of: a) providing an interrogator, said interrogator operable to transmit RF interrogations and to receive RF responses; b) providing a closed loop antenna in electrical communication with said interrogator, said antenna having an inner virtual magnetic loop an outer virtual magnetic loop, said antenna operable to receive said RF responses; c) providing a object, said object having a transponder fixedly attached thereto; d) placing said object in proximity to said closed loop antenna; e) transmitting from said interrogator an RF interrogation; f) receiving by said transponder said RF interrogation; g) transmitting from said transponder an RF response, responsive to said RF interrogation; h) receiving by said antenna said RF response; and i) communicating said RF response from said antenna to said interrogator.
Claim 13
Independent Claim
132 words
A method of identifying objects, the method comprising the steps of: a) providing an interrogator, said interrogator operable to transmit RF interrogations and to receive RF responses; b) providing a closed loop antenna in electrical communication with said interrogator, said antenna having an inner virtual magnetic loop an outer virtual magnetic loop, said antenna operable to receive said RF responses; c) providing a object, said object having a transponder fixedly attached thereto; d) placing said object in proximity to said closed loop antenna; e) transmitting from said interrogator an RF interrogation; f) receiving by said transponder said RF interrogation; g) transmitting from said transponder an RF response, responsive to said RF interrogation; h) receiving by said antenna said RF response; and i) communicating said RF response from said antenna to said interrogator.
Claim 14
Dependent Claim
16 words
The method of claim 11 wherein said antenna is further operable to transmit RF said interrogations.
Claim 15
Dependent Claim
11 words
The method of claim 11 wherein said object is a tire.
Claim 16
Dependent Claim
24 words
The method of claim 11 where a magnetic field of greater than about 100 mA/m is imparted to said transponder by said RF interrogation.
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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) | 1998-07-10 | 1999-01-09 | 1999-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-10 | 2003-01-09 | 2003-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-10 | 2007-01-09 | 2007-07-11 | $7700.00 | Window Closed / Lapsed |