SYSTEMS AND METHODS OF ESTABLISHING RFID NULL ZONES IN DETECTING PRODUCTS IN A RETAIL ENVIRONMENT

• US 20190325173A1
• Filed: 04/17/2019
• Published: 10/24/2019
• Est. Priority Date: 04/20/2018
• Status: Active Grant

• Current Assignee: Walmart Apollo, LLC (WalMart Inc.)
• Original Assignee: Walmart Apollo, LLC (WalMart Inc.)
• Inventors: Tingler, Jeremy R., Lewis, Steven J., Taulbee, Alvin S., Jones, Nicholaus A.
• Granted Patent: US 10,970,495 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 5/015 between indoor and outdoor environments
• CPC Class Codes: G01S 5/016 between areas within a building
• CPC Class Codes: G01S 5/0294 Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10009 sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• 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: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders

Abstract

Some embodiments provide RFID tag reading systems comprising: multiple sets of RFID readers at a retail shopping facility; a tag evaluation control circuit communicatively coupled with the multiple sets of RFID readers and at least one memory, and configured to: receive RFID tag information from the RFID readers; obtain and apply a first set of rules and identify a transition area within the retail shopping facility based on the received RFID tag information; identify a first set of RFID readers configured to read RFID tags as they move through the identified transition area; obtain and apply a second set of rules and establish a first null area adjacent the transition area configured to enable RFID tags crossing through the first null area and prior to entering the transition area to be in a predefined state when entering the transition area.

Claims

1. An RFID (radio frequency identification) tag reading system, comprising:

multiple sets of RFID readers at a retail shopping facility; and

a tag evaluation control circuit communicatively coupled with the multiple sets of RFID readers and at least one memory, and configured to;

receive RFID tag information from the multiple sets of RFID readers, wherein each RFID tag information corresponds to a particular one of numerous RFID tags each associated with a different unique item of products;

obtain a first set of rules to identify a transition area within the retail shopping facility;

apply the first set of rules and identify a first transition area within the retail shopping facility based on the received RFID tag information;

identify a first set of at least one RFID readers of the multiple set of RFID readers configured to read RFID tags as they move through the identified first transition area;

obtain a second set of rules to establish a null area; and

apply the second set of rules and establish a first null area adjacent the first transition area configured to enable RFID tags crossing through the first null area and prior to entering the first transition area to be in a predefined state when entering the first transition area.

2. The system of claim 1, wherein the tag evaluation control circuit in applying the second set of rules and establishing the first null area is configured to:

identify a second set of at least one RFID readers positioned proximate the first null area, and cause an adjustment relative to the second set of at least one RFID readers to reduce RFID read signals relative to the first null area that would prevent one or more of the RFID tags from being in the predefined state when entering the first transition area.

3. The system of claim 2, wherein the tag evaluation control circuit is configured to communicate a power reduction instruction to each RFID reader of the second set of at least one RFID tags to cause each of the RFID readers of the second set of at least one RFID readers to reduce a power level of the RFID read signals transmitted from each of the RFID readers of the second set of at least one RFID readers.

4. The system of claim 2, wherein the tag evaluation control circuit is configured to communicate an instruction to a first RFID reader positioned proximate the null area to induce a cancellation signal configured to cancel out at least a first RFID read signal from one of the second set of RFID readers at least within the null area.

5. The system of claim 2, wherein the tag evaluation control circuit is configured to:

receive RFID tag information from a third set of RFID readers that are configured to read RFID tags while in a third area of the shopping facility that is not part of the first transition area and positioned on a first side of the first transition area;

receive RFID tag information from a fourth set of RFID readers that are configured to read RFID tags while in a fourth area of the shopping facility that is not part of the first transition area and positioned on a second side of the first transition area and separated from the third area by at least the first transition area; and

cause further adjustments relative to the second set of at least one RFID readers to increase a length of the null area when a transition quantity of RFID tags detected as a first set of items are moved through the first transition area is less than a first threshold greater than a third quantity of the RFID tag of the first set of items detected by the third set of RFID readers and is less than a second threshold greater than a fourth quantity of the RFID tags of the first set of items detected by the fourth set of RFID readers.

6. The system of claim 1, wherein the tag evaluation control circuit in identifying the first transition area is configured to identify a threshold number of unique RFID tags corresponding to a threshold number of different types of products over a threshold time period.

7. The system of claim 1, wherein the tag evaluation control circuit is configured to:

obtain a third set of rules to identify a length of a null area;

use the third set of rules to identify over time a desired length of the null area as a function of determined periods of time between when RFID tags are no longer being detected by a first RFID reader of the second set of at least one RFID readers and when the RFID tags are detected by a first RFID reader of the first set of at least one RFID; and

cause an additional adjustment relative to the second set of at least one RFID readers to adjust a length of the first null area to approximately the identified desired length.

8. A method of detecting RFID (radio frequency identification) tags at a retail shopping facility, comprising:

by a tag evaluation control circuit;

receiving RFID tag information from the multiple sets of RFID readers, wherein each RFID tag information corresponds to a particular one of numerous RFID tags each associated with a different unique item of products;

obtaining a first set of rules to identify a transition area within the retail shopping facility;

applying the first set of rules and identifying a first transition area within the retail shopping facility based on the received RFID tag information;

identifying a first set of at least one RFID readers of the multiple set of RFID readers configured to read RFID tags as they move through the identified first transition area;

obtaining a second set of rules to establish a null area; and

applying the second set of rules and establishing a first null area adjacent the first transition area configured to enable RFID tags crossing through the first null area and prior to entering the first transition area to be in a predefined state when entering the first transition area.

9. The method of claim 8, wherein the establishing the first null area comprises:

identifying a second set of at least one RFID readers positioned proximate the first null area, and

causing an adjustment relative to the second set of at least one RFID readers to reduce RFID read signals relative to the first null area that would prevent one or more of the RFID tags from being in the predefined state when entering the first transition area.

10. The method of claim 9, further comprising:

communicating a power reduction instruction to each RFID reader of the second set of at least one RFID tags, and causing each of the RFID readers of the second set of at least one RFID readers to reduce a power level of the RFID read signals transmitted from each of the RFID readers of the second set of at least one RFID readers.

11. The method of claim 9, further comprising:

communicating an instruction to a first RFID reader positioned proximate the null area to induce a cancellation signal configured to cancel out at least a first RFID read signal from one of the second set of RFID readers at least within the null area.

12. The method of claim 9, further comprising:

receiving RFID tag information from a third set of RFID readers that are configured to read RFID tags while in a third area of the shopping facility that is not part of the first transition area and positioned on a first side of the first transition area;

receiving RFID tag information from a fourth set of RFID readers that are configured to read RFID tags while in a fourth area of the shopping facility that is not part of the first transition area and positioned on a second side of the first transition area and separated from the third area by at least the first transition area; and

causing further adjustments relative to the second set of at least one RFID readers increasing a length of the null area when a transition quantity of RFID tags detected as a first set of items are moved through the first transition area is less than a first threshold greater than a third quantity of the RFID tag of the first set of items detected by the third set of RFID readers and is less than a second threshold greater than a fourth quantity of the RFID tags of the first set of items detected by the fourth set of RFID readers.

13. The method of claim 8, wherein the identifying the first transition area comprises identifying a threshold number of unique RFID tags corresponding to a threshold number of different types of products over a threshold time period.

14. The method of claim 8, further comprising:

obtaining a third set of rules to identify a length of a null area;

using the third set of rules and identifying over time a desired length of the null area as a function of determined periods of time between when RFID tags are no longer being detected by a first RFID reader of the second set of at least one RFID readers and when the RFID tags are detected by a first RFID reader of the first set of at least one RFID; and

causing an additional adjustment relative to the second set of at least one RFID readers to adjust a length of the first null area to approximately the identified desired length.