Sleep command for active RF tags to prolong battery life

• US 20060202804A1
• Filed: 03/09/2006
• Published: 09/14/2006
• Est. Priority Date: 03/09/2005
• Status: Abandoned Application

• Current Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Original Assignee: Intermec IP Corporation (Honeywell International Inc.)
• Inventors: Vijay-Pillai, Martinez, Rene, Heinrich, Harley
• Application Number:
  US11/372,563
• Publication Number:
  US 20060202804A1
• Time in Patent Office: Days
• US Class Current: 340/10.330
• CPC Class Codes: G06K 19/0705 the battery being connected to a power saving arrangement
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs

Abstract

Systems and methods are provided for prolong the life of power supplies (e.g., batteries) for RF transponders, such as RFID tags. The method includes receiving one or more RF signals, determining whether one of the RF signals comprises a sleep command, and deactivating the primary circuit of the RF transponder upon determining that one of the received RF signals comprises the sleep command. The primary circuit can be deactivated by disconnecting the power supply, deactivating the primary circuit'"'"'s clock, etc. The method can also include determining whether one of the received RF signals comprises a wake-up command, and activating the primary circuit upon determining that one of the received RF signals comprises the wake-up command. 411951-253

Claims

1. An RF transponder, comprising:

a primary circuit adapted to receive and process RF signals;

a power control circuit in electrical communication with the primary circuit;

an antenna in electrical communication with the primary circuit and the power control circuit;

a power supply operatively coupled to the primary circuit and the power control circuit; and

a switch coupled to the power supply, the primary circuit, and the power control circuit, wherein;

the primary circuit is operatively connected to the power supply when the switch is in a first state, and disconnected from the power supply when the switch is in a second state;

the primary circuit is further adapted to provide a sleep signal to the power control circuit upon detecting a sleep command in one of the received RF signals; and

the power control circuit is adapted to toggle the switch from the first to the second state upon receiving the sleep signal, thereby deactivating the primary circuit to reduce power consumption by the RF transponder.

2. The RF transponder of claim 1, further comprising a voltage regulation circuit that is operatively coupled to the primary circuit and the power supply, and adapted to regulate the voltage provided by the power supply.

3. The RF transponder of claim 1, wherein the primary circuit is adapted to receive RF signals originating from one or more RFID interrogators.

4. The RF transponder of claim 1, wherein:

the primary circuit is further adapted to provide a wake-up signal to the power control circuit upon detecting a wake-up command in one of the received RF signals; and

the power control circuit is further adapted to toggle the switch from the second to the first state upon receiving the wake-up signal, thereby activating the primary circuit.

5. The RF transponder of claim 1, wherein the primary circuit comprises receive/transmit circuits, signal processing logic, and a memory.

6. The RF transponder of claim 1, wherein the power supply is located on board the RF transponder.

7. The RF transponder of claim 6, wherein the power supply comprises a battery.

8. The RF transponder of claim 1, wherein the power supply extracts power from received RF signals.

9. The RF transponder of claim 1, wherein the switch comprises at least one transistor.

10. An RF transponder, comprising:

a primary circuit adapted to receive and process RF signals;

a clock control circuit in electrical communication with the primary circuit;

an antenna in electrical communication with the primary circuit and the clock control circuit; and

a power supply operatively coupled to the primary circuit and the clock control circuit, wherein;

the primary circuit is further adapted to provide a sleep signal to the clock control circuit upon detecting a sleep command in one of the received RF signals;

the clock control circuit is adapted to transmit a stop-clock signal to the primary circuit upon receiving the sleep signal; and

the stop-clock signal disables a clock of the primary circuit, thereby deactivating the primary circuit to reduce power consumption by the RF transponder.

11. The RF transponder of claim 10, further comprising a voltage regulation circuit that is operatively coupled to the primary circuit and the power supply, and adapted to regulate the voltage provided by the power supply.

12. The RF transponder of claim 10, wherein the primary circuit is adapted to receive RF signals originating from one or more RFID interrogators.

13. The RF transponder of claim 10, wherein:

the primary circuit is further adapted to provide a wake-up signal to the clock control circuit upon detecting a wake-up command in one of the received RF signals; and

the clock control circuit is further adapted to provide a start-clock signal to the primary circuit to activate the clock, thereby activating the primary circuit.

14. The RF transponder of claim 10, wherein the primary circuit comprises a receive/transmit circuit, signal processing logic, and a memory.

15. The RF transponder of claim 10, wherein the power supply is located on board the RF transponder.

16. The RF transponder of claim 10, wherein the power supply comprises a battery.

17. The RF transponder of claim 10, wherein the power supply extracts power from received RF signals.

18. The RF transponder of claim 10, wherein the switch comprises at least one transistor.

19. The RF transponder of claim 10, wherein the clock comprises a clocking circuit.

20. The RF transponder of claim 10, wherein the switch comprises an oscillation circuit.

21. The RF transponder of claim 10, wherein the clock control circuit is further adapted to receive RF signals and disable the clock upon detecting the sleep command in one of the received RF signals.

22. A method of operating an RF transponder, comprising:

receiving one or more RF signals;

determining whether one of the RF signals comprises a sleep command;

deactivating a primary circuit adapted to receive and process incoming RF signals upon determining that one of the received RF signals comprises the sleep command;

determining whether one of the received RF signals comprises a wake-up command; and

activating the primary circuit upon determining that one of the received RF signals comprises the wake-up command.

23. The method of claim 22, wherein receiving the one or more RF signals comprises receiving the RF signals from one or more RF interrogators.

24. The method of claim 22, wherein deactivating the primary circuit comprises disconnecting a power supply from the primary circuit.

25. The method of claim 22, wherein deactivating the primary circuit comprises disabling a clock of the primary circuit.

26. The method of claim 22, wherein activating the primary circuit comprises connecting the power supply to the primary circuit.

27. The method of claim 22, wherein activating the primary circuit comprises activating the clock of the primary circuit.