Self checkout system

Patent metadata

Field	Value
Publication number	US-11620880-B2
Application number	US-202117171155-A
Country	US
Kind code	B2
Filing date	Feb 9, 2021
Priority date	Feb 10, 2020
Publication date	Apr 4, 2023
Grant date	Apr 4, 2023

Abstract

Systems and methods for is provided for self-checkout at a point-of-sale. The system and method includes a plurality of radio frequency identification (RFID) transceivers, an RFID reader, wherein the RFID reader is configured to receive a response with an RFID code from each of a plurality of RFID tags activated simultaneously by at least one of the plurality of radio frequency identification (RFID) transceivers, and decode the RFID code from the response received from each of the RFID tags, and a classifier configured to determine whether each of the plurality of RFID tags is inside or outside a walk-through checkout area inside a store, wherein the system calculates an amount charged to a customer based on the cost of the items identified as within the walk-through checkout area.

First claim

What is claimed is:

1. A system for self-checkout at a point-of-sale, comprising:
a plurality of radio frequency identification (RFID) transceivers;
an RFID reader, wherein the RFID reader is configured to receive a response with an RFID code from each of a plurality of RFID tags activated simultaneously by at least one of the plurality of radio frequency identification (RFID) transceivers, and decode the RFID code from the response received from each of the RFID tags; and
a classifier configured to determine whether each of the plurality of RFID tags is inside or outside a walk-through checkout area inside a store, wherein the system calculates an amount charged to a customer based on cost of items identified as within the walk-through checkout area,
wherein each of the plurality of radio frequency identification (RFID) transceivers includes an antenna that is configured as both a transmitter and receiver, only as a transmitter, or only as a receiver in different reading sessions, and
wherein the RFID reader includes a switch configured to receive a selection policy that determines which one(s) of decoded 16-bit random sequence (RN16) signals received from one of the plurality of receiver antennas will be used to generate an acknowledgement.

2. The system as recited in claim 1 , wherein the response from each RFID tag is received simultaneously by an antenna in each of the plurality of radio frequency identification (RFID) transceivers, wherein the antenna is configured as a receiver antenna and a property of a received signal from the plurality of antennas is used to determine a location of each RFID tag.

3. The system as recited in claim 1 , wherein the response from each of multiple RFID tags are decoded simultaneously.

4. The system as recited in claim 1 , wherein boundaries of the walk-through checkout area are determined by signal coverage of a plurality of radio frequency identification (RFID) transmit and receive antennas and a pair of RF-absorbing walls.

5. The system as recited in claim 1 , wherein the classifier determines whether each of a plurality of RFID tags is inside or outside the walk-through checkout area based on one or more properties of the response from the RFID tags.

6. The system as recited in claim 5 , wherein a specific RN16 is selected based on properties of the plurality of decoded RN16s and their corresponding response in a tag reading session from the plurality of antennas.

7. The system as recited in claim 6 , further comprising a waiting area (WA) adjoining the checkout area, wherein at least a subset of the plurality of radio frequency identification (RFID) transceivers are oriented to send signals to and receive signals from the waiting area (WA).

8. The system as recited in claim 5 , wherein proximity of two RFID tags is determined based on the properties of the responses of the two RFID tags, and wherein the proximity between the RFID tags is used as a prior knowledge in determining if one of the two RFID tags is inside or outside a designated area during checkout process.

9. The system as recited in claim 8 , wherein an interference metric is based on a mean and a variance of a set of differences between two symbols in a bi-phase decoder after equalization.

10. The system as recited in claim 1 , wherein each of the decoded RN16s from the plurality of antennas in a single tag reading session receive votes based on a number of antennas that decoded the decoded RN16s, and an antenna is selected which corresponds to the decoded RN16 which has a maximum number of votes.

11. The system as recited in claim 10 , wherein the antenna is selected at random when two or more of the plurality of antennas have a maximum number of votes.

12. The system as recited in claim 1 , further comprising selecting a majority set of RN16s whose constituents have a number of votes above a threshold number from among the multiple RN16s, and selecting the antenna randomly from the majority set.

13. The system as recited in claim 1 , further comprising selecting a majority set of RN16s whose received signal strength of the RN16 signal of the constituent RN16s is above a threshold, and selecting the antenna randomly from the majority set.

14. The system as recited in claim 1 , further comprising selecting a majority set of RN16s whose probability of decoding constituent RN16s is above a threshold, and selecting the antenna randomly from the majority set of RN16s, wherein the probability of decoding is computed based on an interference metric of the decoded RN16.

15. The system as recited in claim 1 , wherein a carrier signal used by a RF chain of a transmit antenna and a receive antenna are synchronized.

16. A system for self-checkout at a point-of-sale, comprising:
a pair of radio frequency (RF)-absorbing walls separated by a distance;
a plurality of radio frequency identification (RFID) elevated transceivers within each of the pair of RF-absorbing walls; and
a plurality of floor-mounted transceivers in a floor below the pair of RF-absorbing walls, wherein the signal coverage of the plurality of radio frequency identification (RFID) transceivers determines a checkout area (CA);
an RFID reader, wherein the RFID reader is configured to receive an RFID code from each of a plurality of RFID tags activated simultaneously by the plurality of radio frequency identification (RFID) transceivers, the RFID reader configured to receive each of the plurality of RFID codes in a separate time slot of a block of a transmit frame;
a classifier configured to determine whether each of the plurality of RFID tags is inside or outside a walk-through checkout area inside a store, wherein the system calculates an amount charged to a customer based on cost of items identified as within the walk-through checkout area; and
a waiting area (WA) adjoining the walk-through checkout area, where at least a subset of the plurality of radio frequency identification (RFID) transceivers are oriented to send signals to and receive signals from the waiting area (WA),
wherein the system is configured to perform a check-in process in order to determine a set of RFID tagged items that enter or return to store, wherein the system is used in a reverse direction by entering from an exit side and exiting from the entrance.

Assignees

• Nec Lab America Inc
• Nec Corp

Inventors

• Khojastepour Mohammad
• Arslan Mustafa
• Rangarajan Sampath
• Chai Eugene
• Bocanegra Carlos

Classifications

• G06N3/0499

  Feedforward networks · CPC title

• G06N3/09

  Supervised learning · CPC title

• G06Q20/204

  comprising interface for record bearing medium or carrier for electronic funds transfer or payment credit · CPC title

• G06K7/10297

  arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 (cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00) · CPC title

• G06N3/048

  Activation functions · CPC title