Multilane vehicle tracking system

• US 8,471,683 B2
• Filed: 06/09/2010
• Issued: 06/25/2013
• Est. Priority Date: 06/09/2010
• Status: Active Grant

• Current Assignee: Neology Incorporated (OEP Technologie BV)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Roesner, Bruce B.
• Primary Examiner(s): Wu, Daniel
• Assistant Examiner(s): LITTLEJOHN JR, MANCIL H
• Application Number:
  US12/797,425
• Publication Number:
  US 20110304441A1
• Time in Patent Office: 1,112 Days
• Field of Search: 340/10.1, 340/10.2, 340/10.3, 340/10.4, 340/10.42, 340/12.51, 340/928, 340/933, 342/373, 342/457, 455/20, 455/2, 455/41.2, 235/384
• US Class Current: 340/10.4
• CPC Class Codes: G07B 15/063 using wireless information transmission between the vehicle and a fixed station identification of vehicles G08G

Abstract

A vehicle tracking system and method of tracking vehicles in multiple traffic lanes is disclosed. One system includes an RFID reader including a plurality of antenna ports. The system also includes a first antenna connected to a first antenna port of the plurality of antenna ports, the first antenna oriented toward a first lane of traffic. The system further includes a second antenna connected to the first antenna port and oriented toward a second lane of traffic. The system also includes a third antenna connected to a second antenna port of the plurality of antenna ports, the third antenna oriented toward the first lane of traffic. In some cases, the RFID reader is configured to detect the existence of a vehicle in a lane based on detection of an RFID device associated with the vehicle at two or more of the plurality of antenna ports.

Claims

1. An object tracking system comprising:

an RFID reader including a plurality of antenna ports;

a first antenna associated with a first antenna port of the plurality of antenna ports, the first antenna oriented toward a first lane;

a second antenna associated with the first antenna port and oriented toward a second lane;

a third antenna associated with a second antenna port of the plurality of antenna ports, the third antenna oriented toward the first lane; and

a fourth antenna associated with the second antenna port and oriented toward the second lane;

wherein a first field associated with the first antenna overlaps a third field associated with the third antenna;

wherein a second field associated with the second antenna overlaps a fourth field associated with the fourth antenna; and

wherein the RFID reader is configured to cycle activation of the antennas so that the first and second fields are active at a first time and the third and fourth fields are active at a second time that differs from the first time.

2. The object tracking system of claim 1, further comprising a splitter electrically connected between the first antenna port, and the first and second antennas.

3. The object tracking system of claim 1, wherein the first and second lanes form at least a portion of a multilane highway.

4. The object tracking system of claim 1, further comprising:

a fifth antenna associated with a third antenna port of the plurality of antenna ports, the fifth antenna oriented toward the second lane; and

a sixth antenna associated with the third antenna port and oriented toward the third lane.

5. The object tracking system of claim 1, further comprising:

a fifth antenna associated with a third antenna port of the plurality of antenna ports, the fifth antenna oriented toward the second lane;

a sixth antenna associated with the third antenna port and oriented toward a fourth lane;

a seventh antenna associated with a fourth antenna port of the plurality of antenna ports, the seventh antenna oriented toward the fourth lane; and

an eighth antenna associated with the fourth antenna port and oriented toward the third lane.

6. The object tracking system of claim 1, wherein the RFID reader is configured to detect an existence of a vehicle in a lane based on detection of an RFID device associated with the vehicle at two or more of the plurality of antenna ports.

7. The object tracking system of claim 1, wherein the RFID reader is configured to detect a position of a vehicle in a lane based on a phase angle of a received signal from an RFID device associated with the vehicle.

8. A method of detecting a vehicle in a lane of traffic, the method comprising:

detecting an RFID tag with one of first and second antennas associated with a first antenna port of an RFID reader, the first antenna being associated with a first lane of traffic and the second antenna associated with a second lane of traffic, and the second lane of traffic being adjacent to the first lane of traffic;

detecting the RFID tag with one of third and fourth antennas associated with a second antenna port of the RFID reader, the third antenna being associated with the first lane of traffic and the fourth antenna being associated with the second lane of traffic;

cycling activation of the antennas so that the first and second fields are active at a first time and the third and fourth fields are active at a second time that differs from the first time; and

determining the presence of the RFID tag within one of the first and second lanes of traffic based on receiving a response signal at the first and second antenna ports.

9. The method of claim 8, wherein detecting the RFID tag with one of first and second antennas comprises activating the first antenna port to transmit a read signal to the first and second antennas.

10. The method of claim 9, wherein detecting the RFID tag with one of first and second antennas comprises receiving a response signal from the RFID tag at one of the first and second antennas, thereby receiving the response signal at the first antenna port.

11. The method of claim 8, further comprising:

detecting a second RFID tag with one of the first and second antennas;

detecting the second RFID tag with the fourth antenna

wherein the RFID reader is configured to determine a presence of the second RFID tag within the lane associated with the fourth antenna based on receiving a response signal at the first and third antenna ports.

12. The method of claim 8, further comprising detecting a position of the RFID tag within one of the first and second lanes of traffic based on a phase angle of a response signal detected by the third antenna and received at the second antenna port.

13. The method of claim 8, wherein the first antenna has a field extending toward the first lane of traffic and which minimizes into the second lane of traffic.

14. The method of claim 13, wherein the second antenna has a field extending toward the second lane of traffic and which minimizes into the first lane of traffic.

15. A vehicle tracking system useable in association with a plurality of lanes of traffic, the vehicle tracking system comprising:

an RFID reader including a plurality of antenna ports;

a first antenna and a second antenna connected to a first antenna port of the plurality of antenna ports via a splitter;

the first antenna having a field extending toward a first lane of traffic and which does not extend into a second lane of traffic; and

the second antenna having a field extending toward the second lane of traffic and which does not extend into the first lane of traffic, the second lane of traffic being adjacent to the first lane of traffic;

a third antenna and a fourth antenna connected to a second antenna port of the plurality of antenna ports via a splitter;

the third antenna having a field extending toward the first lane of traffic and which does not extend into the second lane of traffic; and

the fourth antenna having a field extending toward a third lane of traffic and which does not extend into the first or second lanes of traffic, the third lane of traffic being adjacent to the second lane of traffic;

a fifth antenna and a sixth antenna connected to a third antenna port of the plurality of antenna ports via a splitter;

the fifth antenna having a field extending toward the second lane of traffic and which does not extend into the first or third lanes of traffic; and

the sixth antenna having a field extending toward a fourth lane of traffic and which does not extend into the first, second, or third lanes of traffic, the fourth lane of traffic being adjacent to the third lane of traffic;

a seventh antenna and an eighth antenna connected to a fourth antenna port of the plurality of antenna ports via a splitter;

the seventh antenna having a field extending toward the fourth lane of traffic and which does not extend into the first, second, or third lanes of traffic; and

the eighth antenna having a field extending toward the third lane of traffic and which does not extend into the first, second, or fourth lanes of traffic;

wherein the RFID reader is configured to detect the existence of a vehicle in a lane based on detection of an RFID device associated with the vehicle at two or more of the plurality of antenna ports.

16. The vehicle tracking system of claim 15, wherein the RFID reader is configured to detect a position of the vehicle in a lane based on a phase angle of a received signal from an RFID device associated with the vehicle.