Tracking apparatus, system and method

• US 20050110674A1
• Filed: 10/06/2004
• Published: 05/26/2005
• Est. Priority Date: 03/18/2002
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Paratek Microwave Incorporated (Blackberry Limited)
• Inventors: Toit, Nicolaas du, Toit, Cornelis du, Mendolia, Greg, Kvarnstrand, John, Foo, Bing
• Granted Patent: US 7,183,922 B2
• Time in Patent Office: Days
• US Class Current: 342/81
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 5/04 Position of source determined by a plurality of spaced direction-finders
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: H01Q 1/42 Housings not intimately mechanically associated with radiating elements, e.g. radome
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 3/36 with variable phase-shifters
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40

Abstract

An apparatus capable of tracking a target, comprising at least one near-field focused antenna comprising an array of elements and a phase shifter to form multiple fixed beams in the near-field, a sensor capable of sensing the location of the target, and a controller capable of accepting position information and capable of activating the proper fixed beam along a course so as to enable the near-field focused beams to track the target. The array of elements may be substantially linear and the sensor may be optical, mechanical, thermal, or sonic position detection subsystems. In an embodiment of the present invention the target may be at least one RFID tag and the phase shifter may include a voltage tunable dielectric. The controller may control a plurality of switches which activate at least one beam forming network. Further, the tracking may occur along a predetermined course, and the predetermined course may be along a conveyor line or through a doorway.

Claims

1. An apparatus capable of tracking a target, comprising:

at least one near-field focused antenna comprising an array of elements and a beamformer to form multiple fixed beams in the near-field;

a sensor capable of sensing the location of said target; and

a controller capable of accepting position information and capable of activating the proper fixed beam along a course so as to enable the near-field focused beams to track said target.

2. The apparatus of claim 1, wherein said array of elements is substantially linear.

3. The apparatus of claim 1, wherein said sensor is one or more selected from the following group:

optical, mechanical, thermal, or sonic position detection subsystems.

4. The apparatus of claim 1, wherein said target is at least one RFID tag.

5. The apparatus of claim 1, wherein said beamformer includes at least one phase shifter that includes a voltage tunable dielectric.

6. The apparatus of claim 1, wherein said controller controls a plurality of switches which activate at least one beam forming network.

7. The apparatus of claim 1, wherein said tracking occurs along a predetermined course.

8. The apparatus of claim 7, wherein said predetermined course is along a conveyor line.

9. An apparatus capable of tracking a target, comprising:

an array of elements;

a beamformer capable of forming a continuously scanned beam in the near-field;

a sensor capable of sensing the location of said target; and

a controller capable of accepting position information and activating the proper fixed beam so as to enable near-field focused beams to track said target.

10. The apparatus of claim 9, wherein said tracking occurs along a predetermined course.

11. The apparatus of claim 9, wherein said sensor is one or more selected from the following group:

optical, mechanical, thermal, or sonic position detection subsystems.

12. The apparatus of claim 9, wherein said array of elements is substantially linear.

13. The apparatus of claim 9, wherein said beamformer includes at least one phase shifter that includes a voltage tunable dielectric.

14. A system capable of tracking a target comprising:

at least one near-field focused antenna comprising a set of transmit arrays, wherein each array includes a set of elements arranged substantially in an arc, wherein said arc lies in a plane substantially normal to the direction of motion of said target;

a beamformer for each transmit array capable of forming at least one fixed beam in its near-field;

a sensor capable of determining the location of said target; and

a controller capable of accepting position information and capable of activating the proper fixed beam so as to enable the near-field focused beams to track the target.

15. The apparatus of claim 14, wherein said sensor is one or more selected from the following group:

optical, mechanical, thermal, or sonic position detection subsystems.

16. The apparatus of claim 14, wherein said target is at least one RFID tag.

17. The apparatus of claim 14, wherein said phase shifter includes a voltage tunable dielectric.

18. The apparatus of claim 14, wherein said tracking occurs along a predetermined course.

19. The apparatus of claim 18, wherein said predetermined course is along a conveyor line.

20. A method of tracking a target, comprising:

forming multiple fixed beams in the near-field with at least one near-field focused antenna comprising an array of elements and a phase shifter;

sensing the location of said target with a sensor; and

accepting position information by a controller capable of activating the proper fixed beam along a course so as to enable the near-field focused beams to track said target.

21. The method of claim 20, further comprising placing said array of elements in a substantially linear manner.

22. The method of claim 20, further comprising selecting said sensor from the following group:

optical, mechanical, thermal, or sonic position detection subsystems.

23. The method of claim 20, wherein said target is at least one RFID tag.

24. The method of claim 20, wherein the formation of beams involves the use of at least one said phase shifter that includes a voltage tunable dielectric.

25. The method of claim 20, further comprising controlling by said controller a plurality of switches which activate at least one beam forming network.

26. The method of claim 20, further comprising tracking along a predetermined course.

27. A system capable of tracking an object, comprising:

a conveyor capable of moving said object within a near field focused antenna comprising an arc of transmit antenna arrays, wherein said arc lies in a plane substantially normal to the direction of motion of said target;

a beamformer for each transmit array capable of forming at least one fixed beam in its near-field;

a sensor capable of determining the location of said object; and

a controller capable of accepting position information and capable of activating the proper fixed beam so as to enable the near-field focused beams to track the object.

28. The system of claim 27, wherein said target is at least one RFID tag.