Localizing an RFID tag in a monitored zone

Patent metadata

Field	Value
Publication number	US-12523760-B2
Application number	US-202318348823-A
Country	US
Kind code	B2
Filing date	Jul 7, 2023
Priority date	Jul 29, 2022
Publication date	Jan 13, 2026
Grant date	Jan 13, 2026

Abstract

A method for localizing an RFID tag in a monitored zone comprises: emitting a reference signal from a reference RFID tag at a predefined reference position within the monitored zone, the reference signal including reference information; at a plurality of receivers, receiving the reference signal as a plurality of received reference signals; calculating a position of the reference RFID tag as a function of the received reference signals; comparing the calculated position of the reference RFID tag with the predetermined reference position for obtaining a test result; emitting an operation signal from the RFID tag, the operation signal including operation information associated with the RFID tag; at the plurality of receivers, receiving the operation signal as a plurality of received operation signals, comparing the received operation information with predetermined validation information associated with the RFID tag for obtaining a validation result; as a function of the test result and/or validation result, calculating a position of the RFID tag based on/as a function of the received operation signals and/or generating a position signal indicative of the RFID tag position based on/as a function of the received operation signals.

First claim

The invention claimed is:

1 . A method for localizing an RFID tag in a monitored zone, the method comprising:
emitting a reference signal from a reference RFID tag at a predefined reference position within the monitored zone, the reference signal including reference information; at a plurality of receivers receiving the reference signal as a plurality of received reference signals; calculating a position of the reference RFID tag as a function of the received reference signals; comparing the calculated position of the reference RFID tag with the predetermined reference position; emitting an operation signal from the RFID tag, the operation signal including operation information associated with the RFID tag; at the plurality of receivers receiving the operation signal as a plurality of received operation signals; comparing the received operation information with predetermined validation information associated with the RFID tag for obtaining a validation result; as a function of the test result and/or validation result, calculating a position of the RFID tag based on/as a function of the received operation signals and/or generating a position signal indicative of the position of the RFID tag based on/as a function of the received operation signals.

2 . The method according to claim 1 , wherein the method includes:
sequentially deactivating at least one receiver calculating the position of reference RFID tag as a function of the reference information received by the remaining receiver(s).

3 . The method according to claim 1 , wherein the test result is indicative of a position deviation between the calculated position of the reference RFID tag and the predetermined reference position and/or a previously calculated position.

4 . The method according to claim 3 , wherein comparing the calculated position of the reference RFID tag with the predetermined reference position includes determining if the position deviation is below a predefined threshold.

5 . The method according to claim 1 , wherein the operation and/or reference information includes any of:
encryption key, identification information, time stamp.

6 . The method according to claim 1 , wherein the test and/or validation result is indicative of a compliance with a predefined communication standard.

7 . The method according to claim 1 , wherein comparing the received operation information with predetermined validation information associated with the RFID tag and/or calculating the position of the RFID tag or generating the position signal based on/as a function of the received operation signal is performed at each receiver.

8 . The method according to claim 1 , wherein the method includes comparing the received reference information with predetermined reference information associated with the reference RFID tag.

9 . The method according to claim 1 , wherein calculating the position of the operation RFID tag is blocked if the test result and/or validation result indicates an irregularity state of the RFID tag and/or the receivers; and/or a safety signal is generated if the test result and/or validation result indicates an irregularity state of the RFID tag and/or the receivers, wherein said safety signal is indicative of placing a machine associated with the monitored zone in a safe mode.

10 . The method according to claim 1 , wherein the emitted reference signal has a first frequency, the method further comprising contemporaneously emitting a combined reference signal at the first and at a second frequency; receiving the combined reference signal as a plurality of received combined reference signals calculating a position of the reference RFID tag as a function of the received combined reference signals.

11 . The method according to claim 1 , wherein the emitted operation signal has a first frequency, the method further comprising contemporaneously emitting a combined operation signal at the first and at a second frequency; receiving the combined operation signal as a plurality of received combined operation signals comparing the received operation information with predetermined validation information associated with the received combined operation signals for obtaining the validation result.

12 . The method according to claim 1 , wherein at least a subset of the steps of the method are performed periodically according to a predetermined period.

13 . A localization system for localizing an RFID tag in a monitored zone, comprising:
at least a reference RFID tag for emitting a reference signal, the reference signal including reference information; at least a RFID tag for emitting an operation signal including operation information associated with the RFID tag; a plurality of receivers for receiving the reference signal as a plurality of received reference signals and for receiving the operation signal as a plurality of received operation signals; a safety unit configured for:
calculating a position of the reference RFID tag as a function of the received reference signals;
comparing the calculated position of the reference RFID tag with the predetermined reference position for obtaining a test result;
comparing the received operation information with predetermined validation information associated with the RFID tag for obtaining a validation result;
as a function of the test result and/or validation result, calculating a position of the RFID tag based on/as a function of the received operation signals and/or generating a position signal indicative of the RFID tag position based on/as a function of the received operation signals.

14 . The localization system according to claim 13 , wherein the safety unit is at least partially comprised in any of the receivers.

15 . The localization system according to claim 13 , further comprising a wearable to be worn by an operator entering the monitored zone, the wearable including the RFID tag.

Assignees

• Omron Tateisi Electronics Co

Inventors

• Romano Enzo
• Grange Gianmarco
• Viviani Paolo
• Cambursano Maurizio

Classifications

• G01S2205/01

  specially adapted for specific applications · CPC title

• G01S5/0205

  Details · CPC title

• G01S5/02213

  Receivers arranged in a network for determining the position of a transmitter · CPC title

• G01S5/0226

  Transmitters · CPC title

• G01S5/021

  Calibration, monitoring or correction (G01S5/0252 takes precedence) · CPC title