Advanced micro-location of RFID tags in spatial environments

• US 10,586,082 B1
• Filed: 08/16/2019
• Issued: 03/10/2020
• Est. Priority Date: 05/29/2019
• Status: Active Grant

• Current Assignee: Fellow Incorporated
• Original Assignee: Fellow Incorporated
• Inventors: Tang, Xinyi Daniel, Sinha, Utkarsh, Barry, Daniel Thomas, Mahendran, Jagadish, Medina, Marco Octavio Mascorro
• Primary Examiner(s): Nguyen, Tai T
• Application Number:
  US16/543,395
• Time in Patent Office: 207 Days
• Field of Search: 3405724, 3405727, 340505, 340 1031, 340 105, 340 1041
• CPC Class Codes: G01S 13/505 using Doppler effect for determining closest range to a target or corresponding time, e.g. miss-distance indicator
• CPC Class Codes: G01S 13/75 using transponders powered from received waves, e.g. using passive transponders , or using passive reflectors
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G06K 7/10099 the directional field being used for pinpointing the location of the record carrier, e.g. for finding or locating an RFID tag amongst a plurality of RFID tags, each RFID tag being associated with an object, e.g. for physically locating the RFID tagged object in a warehouse
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
• CPC Class Codes: G06N 20/00 Machine learning
• CPC Class Codes: H04B 17/318 Received signal strength

Abstract

Advanced micro-location of RFID tags in 3D and 2D spatial environments includes a mobile platform having a known location within a three-dimensional (3D) space. A plurality of RFID tags is located within the 3D space. A plurality of RFID antennas is mounted on the mobile platform, wherein backscatter signals of at least one of the RFID tags are collected by at least one of the plurality of RFID antennas and time-synchronized with the known location of the mobile platform in the 3D space at a time of collection. A computerized processing device is in communication with the plurality of RFID antennas. The computerized processing device performs algorithmic RFID tag localization using at least the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the mobile platform to determine a micro-location of the at least one RFID tag within the 3D space.

Claims

1. A system for micro-location of RFID tags within a spatial environment comprising:

a mobile platform having a known location within a three-dimensional (3D) space, wherein a plurality of radio frequency identification (RFID) tags are located within the 3D space;

a plurality of RFID antennas mounted on the mobile platform, wherein backscatter signals of at least one of the RFID tags are collected by at least one of the plurality of RFID antennas and time-synchronized with the known location of the mobile platform in the 3D space at a time of collection; and

a computerized processing device in communication with the plurality of RFID antennas, wherein the computerized processing device performs algorithmic RFID tag localization using at least the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the mobile platform to determine a micro-location of the at least one RFID tag within the 3D space;

wherein the algorithmic RFID tag localization further comprises;

creating a history of phase and received signal strength indicator (RSSI) of the collected backscatter signals of the at least one RFID tag over a period of time;

evaluating possible RFID tag locations;

simulating a received signal phase and RSSI; and

matching the history of phase and RSSI of the collected backscatter signals to the simulated received signal phase and RSSI.

2. The system of claim 1, wherein the mobile platform further comprises at least one of:

a wheeled platform, a handheld platform, a robotic platform, a drone platform, a track-based platform, and an aerial platform.

3. The system of claim 1, wherein the plurality of RFID antennas mounted on the mobile platform are mounted facing laterally relative to a direction of movement of the mobile platform.

4. The system of claim 1, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to recognize patterns in the collected backscatter signals, wherein the micro-location of the at least one RFID tag within the 3D space is determined.

5. The system of claim 1, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to determine the micro-location of the at least one RFID tag based on correlations between a relative position of the mobile platform and the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the mobile platform.

6. The system of claim 1, wherein the algorithmic RFID tag localization further comprises associating the collected backscatter signals of the at least one RFID tag with interrogation signals emitted, wherein the micro-location of the at least one RFID tag is determined triangulation based on a time between an emission and a collection of the interrogation signals.

7. The system of claim 1, wherein the algorithmic RFID tag localization further comprises analyzing a Doppler frequency shift as the mobile platform moves past the at least one RFID tag.

8. The system of claim 1, wherein the algorithmic RFID tag localization further comprises using two or more RFID tag localization techniques.

9. The system of claim 1, wherein the location of the mobile platform within the 3D space is known using:

one or more ultra-wideband (UWB) devices;

one or more Light Detection and Ranging (LIDAR) devices; and

/or one or more 3D Simultaneous Localization and Mapping (SLAM) devices.

10. A method for micro-location of RFID tags within a spatial environment, the method comprising steps of:

providing a plurality of radio frequency identification (RFID) tags within a three dimensional (3D) space;

moving a mobile platform, within the 3D space, wherein the mobile platform has a known location;

collecting, with a plurality of RFID antennas mounted on the mobile platform, backscatter signals of at least one of the RFID tags;

time-synchronizing the collected backscatter signals with the known location of the mobile platform in the 3D space at a time of collection; and

performing algorithmic RFID tag localization using at least, the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the mobile platform, thereby determining a micro-location of the at least one RFID tag within the 3D space;

wherein the algorithmic RFID tag localization further comprises;

creating a history of phase and received signal strength indicator (RSSI) of the collected backscatter signals of the at least one RFID tag over a period of time;

evaluating possible RFID tag locations;

simulating a received signal phase and RSSI; and

matching the history of phase and RSSI of the collected backscatter signals to the simulated received signal phase and RSSI.

11. The method of claim 10, wherein moving the mobile platform within the 3D space further comprises at least one of:

a wheeled movement, a handheld movement, a robotic movement, a drone movement, a track-based movement, and an aerial movement.

12. The method of claim 10, wherein the plurality of RFID antennas mounted on the mobile platform are mounted facing laterally relative to a direction of movement of the mobile platform.

13. The method of claim 10, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to recognize patterns in the collected backscatter signals, wherein the micro-location of the at least one RFID tag within the 3D space is determined.

14. The method of claim 10, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to determine the micro-location of the at least one RFID tag based on correlations between a relative position of the mobile platform and the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the mobile platform.

15. The method of claim 10, wherein the algorithmic RFID tag localization further comprises associating the collected backscatter signals of the at least one RFID tag with interrogation signals emitted, wherein the micro-location of the at least one RFID tag is determined triangulation based on a time between an emission and a collection of the interrogation signals.

16. The method of claim 10, wherein the algorithmic RFID tag localization further comprises analyzing a Doppler frequency shift as the mobile platform moves past the at least one RFID tag.

17. The method of claim 10, wherein the algorithmic RFID tag localization further comprises using two or more RFID tag localization techniques.

18. The method of claim 10, wherein the location of the mobile platform within the 3D space is known using:

one or more ultra-wideband (UWB) devices;

one or more Light Detection and Ranging (LIDAR) devices; and

/or one or more 3D Simultaneous Localization and Mapping (SLAM) devices.

19. A system for tracking a micro-location of RFID tags within a spatial environment comprising:

at least one radio frequency identification (RFID) tag moving within a three-dimensional (3D) space;

a plurality of RFID antennas fixedly positioned within the 3D space, wherein backscatter signals of the at least one RFID tag is collected by at least one of the plurality of RFID antennas and time-synchronized with a known location of the at least one of the plurality of RFID antennas in the 3D space at a time of collection; and

a computerized processing device in communication with the plurality of RFID antennas, wherein the computerized processing device performs algorithmic RFID tag localization using at least the collected backscatter signals of the at least one RFID tag and the time-synchronized known location of the at least one of the plurality of RFID antennas to determine a micro-location of the at least one RFID tag within the 3D space;

wherein the algorithmic RFID tag localization further comprises;

creating a history of phase and received signal strength indicator (RSSI) of the collected backscatter signals of the at least one RFID tag over a period of time;

evaluating possible RFID tag locations;

simulating a received signal phase and RSSI; and

matching the history of phase and RSSI of the collected backscatter signals to the simulated received signal phase and RSSI.

20. The system of claim 19, wherein one or more of the plurality of RFID antennas is fixedly positioned:

on a door;

proximate to a conveyor belt;

on a stationary mechanical device;

or on a structure of the 3D space.

21. The system of claim 19, wherein the plurality of RFID antennas are mounted facing laterally relative to a direction of movement of the at least one RFID tag.

22. The system of claim 19, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to recognize patterns in the collected backscatter signals, wherein the micro-location of the at least one RFID tag within the 3D space is determined.

23. The system of claim 19, wherein the algorithmic RFID tag localization further comprises utilizing a machine learning model to determine the micro-location of the at least one RFID tag based on correlations between a relative position of the at least one of the plurality of RFID antennas and the collected backscatter signals of the at least one RFID tag and the time-synchronized known location.

24. The system of claim 19, wherein the algorithmic RFID tag localization further comprises associating the collected backscatter signals of the at least one RFID tag with interrogation signals emitted, wherein the micro-location of the at least one RFID tag is determined triangulation based on a time between an emission and a collection of the interrogation signals.

25. The system of claim 19, wherein the algorithmic RFID tag localization further comprises analyzing a Doppler frequency shift as the at least one RFID tag moves past the at least one of the plurality of RFID antennas.

26. The system of claim 19, wherein the algorithmic RFID tag localization further comprises using two or more RFID tag localization techniques.