Systems and methods for operating a tag

Patent metadata

Field	Value
Publication number	US-2019108370-A1
Application number	US-201816145283-A
Country	US
Kind code	A1
Filing date	Sep 28, 2018
Priority date	Oct 10, 2017
Publication date	Apr 11, 2019
Grant date	—

Abstract

Systems and methods for operating a Radio Frequency Identification (“RFID”) tag. The methods comprise: monitoring a level of Radio Frequency (“RF”) energy being received by the RFID tag; performing operations by a circuit of the RFID tag to compare the level of RF energy in a given frequency band to a first threshold value; and transitioning an operational mode of the RFID tag from a first operational mode in which a receiver is disabled to a second operational mode in which the receiver is enabled, when the level of RF energy exceeds the first threshold value. The RFID tag is able to communicate with a remote tag reader when the RFID tag is in the second operational mode and not when the RFID tag is in the first operational mode.

First claim

What is claimed is:

1 . A method for operating a first Radio Frequency Identification (“RFID”) tag, comprising:
monitoring a level of Radio Frequency (“RF”) energy being received by the first RFID tag;
performing operations by a circuit of the first RFID tag to compare the level of RF energy in a given frequency band to a first threshold value; and
transitioning an operational mode of the first RFID tag from a first operational mode in which a receiver is disabled to a second operational mode in which the receiver is enabled, when the level of RF energy exceeds the first threshold value;
wherein the first RFID tag is able to communicate with a remote tag reader when the first RFID tag is in the second operational mode and not when the first RFID tag is in the first operational mode.

2 . The method according to claim 1 , wherein the first operational mode comprises a power recharging mode in which a rechargeable power source is charged using harvested energy.

3 . The method according to claim 1 , wherein the first operational mode comprises a power save mode.

4 . The method according to claim 1 , wherein the first RFID tag is configured to communicate with the remote tag reader during at least one time slot.

5 . The method according to claim 4 , wherein the at least one time slot comprises a time slot that is allocated to at least one other second RFID tag in accordance with a time slotted communication scheme.

6 . The method according to claim 1 , further comprising selecting the first threshold value based on at least one of (a) a number of communication collisions that occurred during a time period, (b) a number of times a first RFID tag transmitted a signal during a time period, (c) a period of time since the first RFID tag received a last interrogation signal, (d) a purpose or intended use of the first RFID tag, (e) a physical location of the first RFID tag in a facility, (f) a number of other second RFID tags in proximity to the first RFID tag, (g) the first RFID tag's power source level of charge, and/or (h) current conditions of a surrounding environment.

7 . The method according to claim 1 , further comprising performing operations by the first RFID tag to determine if a power source's level of charge is below a second threshold value.

8 . The method according to claim 7 , further comprising transitioning the operational mode of the first RFID tag to a passive mode in which the first RFID tag is powered off when the power source's level of charge is below a second threshold value.

9 . The method according to claim 8 , further comprising allowing the first RFID tag to communicate when a pre-defined level of RF energy is received at the first RFID tag.

10 . The method according to claim 9 , wherein the pre-defined level of RF energy is lower than the level of RF energy compared with the first threshold value.

11 . The method according to claim 9 , further comprising performing communications operations by the first RFID tag to receive and respond to one or more interrogation signals transmitted from the remote tag reader, when in the second operational mode.

12 . The method according to claim 11 , further comprising discontinuing the communications operations when a power source has a certain level of charge, a control signal is received from an external device to disable the receiver, expiration of a time slot, or completion of the first RFID tag's communications with the remote tag reader.

13 . The method according to claim 1 , further comprising performing operations by the first RFID tag, prior to said transitioning, to determine whether the operational mode thereof should be transitioned from the first operational mode based on at least one of (a) time since last communication, (b) current operational state of the first RFID tag, (c) a threshold level, (e) a number of communication collisions that occurred during a time period, (f) a number of times a first RFID tag transmitted a signal during a time period, (g) a period of time since the first RFID tag received a last interrogation signal, (h) a purpose or intended use of the first RFID tag, (i) a physical location of the first RFID tag in a facility, (j) a number of other second RFID tags in proximity to the first RFID tag, (k) the first RFID tag's power source level of charge, and (l) current conditions of a surrounding environment.

14 . A Radio Frequency Identification (“RFID”) tag, comprising:
a receiver; and
a circuit configured to
monitor a level of Radio Frequency (“RF”) energy being received by the RFID tag,
compare the level of RF energy in a given frequency band to a first threshold value, and
transition an operational mode of the RFID tag from a first operational mode in which the receiver is disabled to a second operational mode in which the receiver is enabled, when the level of RF energy exceeds the first threshold value;

wherein the RFID tag is able to communicate with a remote tag reader when the RFID tag is in the second operational mode and not when the RFID tag is in the first operational mode.

15 . The RFID tag according to claim 14 , wherein the first operational mode comprises a power recharging mode in which a rechargeable power source is charged using harvested energy.

16 . The RFID tag according to claim 14 , wherein the first operational mode comprises a power save mode.

17 . The RFID tag according to claim 14 , wherein the RFID tag communicates with the remote tag reader during at least one time slot.

18 . The RFID tag according to claim 17 , wherein the at least one time slot comprises a time slot that is allocated to at least one other RFID tag in accordance with a time slotted communication scheme.

19 . The RFID tag according to claim 14 , wherein the first threshold value is selected based on at least one of (a) a number of communication collisions that occurred during a time period, (b) a number of times the RFID tag transmitted a signal during a time period, (c) a period of time since the RFID tag received a last interrogation signal, (d) a purpose or intended use of the RFID tag, (e) a physical location of the RFID tag in a facility, (f) a number of other RFID tags in proximity to the RFID tag, (g) the RFID tag's power source level of charge, and/or (h) current conditions of a surrounding environment.

20 . The RFID tag according to claim 14 , wherein the RFID tag determines if a power source's level of charge is below a second threshold value.

21 . The RFID tag according to claim 20 , wherein the operational mode of the RFID tag is transitioned to a passive mode in which the RFID tag is powered off when the power source's level of charge is below a second threshold value.

22 . The RFID tag according to claim 21 , wherein the RFID tag is allowed to communicate when a pre-defined level of RF energy is received at the RFID tag.

23 . The RFID tag according to claim 22 , wherein the pre-defined level of RF energy is lower than the level of RF energy compared with the first threshold value.

24 . The RFID tag according to claim 22 , wherein the RFID tag performs communication operations to receive and respond to one or more interrogation signals transmitted from the remote tag reader, when in the second operational mode.

25 . The RFID tag according to claim 24 , wherein the communications operations are discontinued when a power source has a certain level of charge, a control signa

Assignees

• Trivelpiece Steve E
• Trivelpiece Craig E
• Riggert Eric F
• Tyco Fire & Security Gmbh

Inventors

• Trivelpiece Steve E
• Trivelpiece Craig E
• Riggert Eric F

Classifications

• G06K7/10217

  parameter settings controlling the transmission power of the interrogator · CPC title

• G06K7/0008

  General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer · CPC title

• G06K7/10029 Primary

  the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot · CPC title

• G06K19/0723 Primary

  the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs · CPC title

• G06K19/0712

  the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier (active means for hindering electromagnetic reading or writing G06K19/07336) · CPC title