Ceiling-mounted RFID-enabled tracking

• US 9,841,492 B2
• Filed: 08/15/2016
• Issued: 12/12/2017
• Est. Priority Date: 02/25/2013
• Status: Active Grant

• Current Assignee: Quake Global, Inc.
• Original Assignee: Quake Global, Inc.
• Inventors: Karani, Chetan Shantilal, Waidmann, Luke Christopher, Bolger-Kumm, Walker Edward, Wisdom, Ronan
• Primary Examiner(s): Alam, Mirza
• Application Number:
  US15/237,400
• Publication Number:
  US 20160349352A1
• Time in Patent Office: 484 Days
• Field of Search: 340 101, 3405727, 34053913, 340 103, 34053922, 235385, 235451, 4555621, 455272
• CPC Class Codes: G01S 11/06 using intensity measurements
• 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 3/38 using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal G01S3/16, G01S3/28 take precedence
• CPC Class Codes: G01S 5/0294 Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• CPC Class Codes: H01Q 21/06 Arrays of individually energised antenna units similarly polarised and spaced apart

Abstract

Systems and methods for tracking a subject using radio-frequency identification (RFID). In an embodiment, an antenna array comprising a plurality of articulating brackets and a plurality of antennas is provided. Each of the articulating brackets is configured to move one of the plurality of antennas into a plurality of positions, and each of the antennas is configured to receive a RFID signal. In addition, a processor receives RFID data based on RFID signals received by the antennas of the antenna array, and determines a trajectory of a subject based on the RFID data. Based on the determined trajectory of the subject, the processor controls one or more of the articulating brackets to move one or more of the antennas into a position to track the subject.

Claims

1. An apparatus for tracking a subject using radio-frequency identification (RFID), the apparatus comprising:

an antenna array comprising a plurality of articulating brackets and a plurality of antennas, wherein each of the plurality of articulating brackets is configured to rotate a corresponding one of the plurality of antennas into a plurality of orientations, and wherein each of the plurality of antennas is configured to receive an RFID signal from an RFID tag; and

at least one processor that

detects whether or not at least one tracking target is present;

when the presence of at least one tracking target is not detected, operates the antenna array in a low power mode, and,

when the presence of at least one tracking target is detected, operates the antenna array in an active power mode by at least

determining a distance between the at least one tracking target and the antenna array based on a strength of one or more signals received by the antenna array,

determining a trajectory of the at least one tracking target based on the determined distance, and,

based on the determined trajectory of the at least one tracking target, automatically controlling a first articulating bracket of the antenna array to rotate a first antenna of the antenna array into a new orientation to continue tracking the at least one tracking target.

2. The apparatus of claim 1, wherein rotating the first antenna comprises changing a directionality of the first antenna to be directed towards the determined trajectory of the at least one tracking target.

3. The apparatus of claim 1, wherein determining the trajectory of the at least one tracking target comprises determining one or more locations of the at least one tracking target based on the strength of one or more signals received by the antenna array.

4. The apparatus of claim 1, wherein the one or more signals received by the antenna array comprises a plurality of signals, and wherein determining the trajectory of the at least one tracking target comprises determining a direction of the at least one tracking target based on the plurality of signals.

5. The apparatus of claim 1, wherein the one or more signals received by the antenna array comprises a plurality of signals, and wherein determining the trajectory of the at least one tracking target comprises determining a speed of the at least one tracking target based on the plurality of signals.

6. The apparatus of claim 1, wherein determining the trajectory of the at least one tracking target comprises determining the trajectory of the at least one tracking target based on one or more of a strength, sampling rate, direction, phase, and time span of the one or more signals received by the antenna array.

7. The apparatus of claim 1, wherein the at least one processor is configured to control the plurality of articulating brackets such that directionalities of the plurality of antennas form a plurality of zones.

8. The apparatus of claim 7, wherein two or more of the plurality of zones overlap.

9. The apparatus of claim 1, further comprising one or more sensors that detect one or more environmental conditions.

10. The apparatus of claim 9, wherein the one or more environmental conditions comprise a presence of the at least one tracking target, and wherein the at least one processor detects whether or not the at least one tracking target is present based on at least one signal, indicating the presence of the at least one tracking target, received from the one or more sensors.

11. The apparatus of claim 1, further comprising a communication device configured to communicate with an external control device.

12. The apparatus of claim 11, wherein the communication between the communication device and the external control device comprises wireless communication.

17. The apparatus of claim 1, wherein rotating the first antenna into a new orientation comprises rotating the first antenna into a new orientation that extends a boundary coverage of the antenna array in a direction along the determined trajectory.

18. The apparatus of claim 10, wherein the one or more sensors that detect the presence of the at least one tracking target comprise a motion sensor.

13. A method for tracking a subject using an antenna array comprising:

detecting whether or not at least one tracking target is present;

when the presence of at least one tracking target is not detected, operates the antenna array in a low power mode; and

,

when the presence of at least one tracking target is detected, operates the antenna array in an active power mode by at least

determining a distance between the at least one tracking target and the antenna array based on a strength of one or more signals received by the antenna array,

determining a trajectory of the at least one tracking target based on the determined distance, and,

based on the determined trajectory of the at least one tracking target, automatically controlling a first articulating bracket of the antenna array to rotate a first antenna of the antenna array into a new orientation to continue tracking the at least one tracking target.

14. The method of claim 13, wherein determining the trajectory of the at least one tracking target further comprises determining the trajectory of the at least one tracking target based on one or more of a strength, sampling rate, direction, phase, and time span of one or more signals received by the antenna array.

15. The method of claim 13, further comprising controlling a plurality of articulating brackets such that directionalities of a plurality of antennas of the antenna array form a plurality of zones.

16. The method of claim 15, wherein two or more of the plurality of zones overlap.