US5351052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transponder systems for automatic identification purposes
Assignee: Texas Instruments Inc
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Filing: 1993-06-28
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Granted: 1994-09-27
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Expires: 2013-06-28
Abstract
Abstract A method of communicating between an interrogator (10) and at least a first and second transponder (12). The transponders (12) are separately located within a first and a second vehicle (20) travelling within a first and a second traffic lane, respectively. The method has the steps of providing a first and a second LF antenna (16) associated with and proximity to a first and a second traffic lane, respectively. From each of the first and second LF antennas (16) a continuous LF subcarrier is transmitted to serve as a clock signal for each antenna's associated transponder (12). Initially, a wake-up signal is sent by each of the LF antennas (16) to its associated transponder (12). Following the wake-up signal, a unique lane code is sent by each of the LF antennas (16) to its associated transponder (12). The transponder (12) stores its unique lane code in its memory (70). The transponder then sends a UHF response in a pre-determined time period depending on the unique lane code stored in each of the transponders (12). The time period in which the transponder (12) sends its UHF response is unique to that transponder (12) so that interference between responding transponders (12)is avoided. Other devices, systems and methods are also disclosed.
Inventors
- 👤 Loek D'Hont
- 👤 Anne Tip
- 👤 Herbert Meier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:41
CPC Classifications
G; G07; G07B; G07B15/00; G07B15/06; G07B15/063; G06; G06K; G06K7/00; G06K7/0008; G08; G08G; G08G1/00; G08G1/01; G08G1/017; G01; G01S; G01S13/00; G01S13/74; G01S13/76; G01S13/78
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
178 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second vehicle travelling within a first and a second traffic lane, respectively, the method comprising the steps of: a) providing a first and a second LF antenna associated with and in proximity to said first and said second traffic lane, respectively; b) transmitting from each of said first and second LF antennas a continuous LF subcarrier to serve as a clock signal for each antenna's associated transponder; c) sending a wake-up signal by each of said LF antennas to its associated transponder; d) sending a unique lane code by each of said LF antennas to its associated transponder; e) storing said unique lane code in a memory in each of said transponders; and f) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique lane code stored in each of said transponders whereby interference between responding transponders is avoided.
Claim 2
Independent Claim
178 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second vehicle travelling within a first and a second traffic lane, respectively, the method comprising the steps of: a) providing a first and a second LF antenna associated with and in proximity to said first and said second traffic lane, respectively; b) transmitting from each of said first and second LF antennas a continuous LF subcarrier to serve as a clock signal for each antenna's associated transponder; c) sending a wake-up signal by each of said LF antennas to its associated transponder; d) sending a unique lane code by each of said LF antennas to its associated transponder; e) storing said unique lane code in a memory in each of said transponders; and f) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique lane code stored in each of said transponders whereby interference between responding transponders is avoided.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein a first and second interrogator are provided for receiving said UHF response from said first and second transponders, respectively.
Claim 4
Dependent Claim
21 words
The method of claim 2 wherein said first and second interrogators are further operable to send UHF interrogations to said transponders.
Claim 5
Dependent Claim
32 words
The method of claim 1 and further comprising the step of having a brief pause after said wake-up signal during which no signals are sent by said LF antennas or said transponders.
Claim 6
Dependent Claim
22 words
The method of claim 1 wherein a single UHF interrogator is provided to accomplish reception of all UHF responses from said transponders.
Claim 7
Dependent Claim
19 words
The method of claim 5 wherein said UHF interrogator is further operable to send UHF interrogations to said transponders.
Claim 8
Independent Claim
130 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second area, comprising the steps of: a) providing a first and a second LF antenna associated with and in proximity to said first and said second area, respectively; b) transmitting from each of said first and second LF antennas a continuous LF sub-carrier to serve as a clock signal for each antenna's associated transponder; c) sending a unique area code by each of said LF antennas to its associated transponder; and d) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique area code whereby interference between responding transponders is avoided.
Claim 9
Independent Claim
130 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second area, comprising the steps of: a) providing a first and a second LF antenna associated with and in proximity to said first and said second area, respectively; b) transmitting from each of said first and second LF antennas a continuous LF sub-carrier to serve as a clock signal for each antenna's associated transponder; c) sending a unique area code by each of said LF antennas to its associated transponder; and d) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique area code whereby interference between responding transponders is avoided.
Claim 10
Dependent Claim
25 words
The method of claim 7 wherein a first and second interrogator are provided for receiving said UHF response from said first and second transponder, respectively.
Claim 11
Dependent Claim
18 words
The method of claim 8 wherein said first and second interrogators operate using different UHF channel carrier frequencies.
Claim 12
Dependent Claim
35 words
The method of claim 7 and further comprising the step of sending a wake-up signal by each of said LF antennas to its associated transponder prior to said step of sending said unique area code.
Claim 13
Dependent Claim
33 words
The method of claim 10 and further comprising the step of having a brief pause after said wake-up signal during which no signals are sent by said LF antennas and by said transponders.
Claim 14
Dependent Claim
19 words
The method of claim 7 wherein said unique area code is transmitted by pulse-width modulation of the LF carrier.
Claim 15
Dependent Claim
19 words
The method of claim 7 wherein said unique area code is transmitted by amplitude modulation of the LF carrier.
Claim 16
Dependent Claim
23 words
The method of claim 7 wherein said LF carrier is used as a reference clock signal for at least one of said transponders.
Claim 17
Dependent Claim
19 words
The method of claim 7 wherein said unique area code is transmitted by phase-amplitude modulation of the LF carrier.
Claim 18
Dependent Claim
17 words
The method of claim 7 wherein said transponders are in motion within said first and second areas.
Claim 19
Dependent Claim
17 words
The method of claim 16 wherein said UHF response is by back-scatter modulation of a UHF carrier.
Claim 20
Dependent Claim
21 words
The method of claim 17 wherein the velocity of said transponder is measured by the doppler shift of said UHF carrier.
Claim 21
Independent Claim
181 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second area, comprising the steps of: a) providing a first and a second LF antenna associated with and proximity to said first and said second area, respectively, said first and second LF antenna operating under control of a first and second interrogator, respectively; b) transmitting from each of said first and second LF antennas a continuous LF sub-carrier to serve as a clock signal for each antenna's associated transponder; c) sending a wake-up signal by each of said LF antennas to its associated transponder wherein said first and second interrogator transmit their wake-up pulses simultaneously whereby said first and second transponders have a common temporal reference; d) sending a unique area code by each of said interrogators to its associated transponder; and e) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique area code whereby interference between responding transponders is avoided.
Claim 22
Independent Claim
181 words
A method of communicating between an interrogator and a plurality of transponders, at least a first and a second of said transponders separately located within a first and a second area, comprising the steps of: a) providing a first and a second LF antenna associated with and proximity to said first and said second area, respectively, said first and second LF antenna operating under control of a first and second interrogator, respectively; b) transmitting from each of said first and second LF antennas a continuous LF sub-carrier to serve as a clock signal for each antenna's associated transponder; c) sending a wake-up signal by each of said LF antennas to its associated transponder wherein said first and second interrogator transmit their wake-up pulses simultaneously whereby said first and second transponders have a common temporal reference; d) sending a unique area code by each of said interrogators to its associated transponder; and e) sending a UHF response by each of said transponders in a pre-determined, mutually exclusive, time period depending on said unique area code whereby interference between responding transponders is avoided.
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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) | 1997-09-26 | 1998-03-28 | 1998-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-26 | 2002-03-28 | 2002-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-26 | 2006-03-28 | 2006-09-27 | $7700.00 | Window Closed / Lapsed |