RADIO FREQUENCY IDENTIFICATION TRANSPONDER

• US 20070139160A1
• Filed: 10/03/2006
• Published: 06/21/2007
• Est. Priority Date: 02/28/2000
• Status: Active Grant

• Current Assignee: SATO Holdings Corporation
• Original Assignee: Magellan Technology Pty. Ltd (SATO Holdings Corporation)
• Inventors: Stanton, Michael, Littlechild, Stuart
• Granted Patent: US 8,319,609 B2
• Time in Patent Office: Days
• US Class Current: 340/10.100
• 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
• 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 7/10029 the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot
• CPC Class Codes: G06K 7/10435 the interrogation device being positioned close to a conveyor belt or the like on which moving record carriers are passing conveying in accordance with bodily destination marks, see B65G47/46, sorting of objects carrying identity markings, see B07C5/34

Abstract

A radio frequency identification transponder including a power supply and a dynamic memory array which stores data. When power from the power supply ceases, the data in the dynamic memory array is validly maintained for a predetermined period of time. The dynamic memory array is responsive to an interrogating signal for selectively updating the data. A signal processor extracts an identifier from the interrogation signal and is responsive to the identifier and the stored data to determine whether some or all of the identifier is stored in the dynamic memory array.

Claims

1. A radio-frequency identification (“

RFID”

) interrogator for interrogating a plurality of RFID transponders, the RFID interrogator including;

a transmitter for providing a plurality of temporally spaced interrogating signals, wherein the each of the plurality of temporally spaced signals includes a respective identifier;

a receiver for receiving response signals from the plurality of RFID transponders, the response signals including respective identity data derived from at least one of the plurality of temporally spaced interrogating signals; and

a signal processor responsive to the receiver for extracting identity data from the response signals to determine an order in which the transponders were first in receipt of an interrogating signal.

2. The transponder according to claim 1 wherein:

the RFID interrogator is a TRP and the plurality of RFID transponders are attached to respective articles being progressed through the TRP;

the signal processor is responsive to a determination of the order in which the transponders were first in receipt of an interrogating signal for determining an order in which the articles progress through the TRP.

3. A method of interrogating a plurality of radio-frequency identification (“

RFID”

) transponders with an RFID interrogator, the method including the steps of;

providing a plurality of temporally spaced interrogating signals to the plurality of RFID transponders, wherein the interrogating signals include respective identifiers;

receiving response signals from respective RFID transponders of the plurality of RFID transponders with a receiver, the response signals including respective identity data derived from at least one of the interrogating signals; and

being responsive to the receiver for extracting the identity data from the response signals to determine an order in which the RFID transponders were first in receipt of an interrogating signal.

4. A plurality of radio-frequency identification (“

RFID”

) transponders for use with an RFID interrogator that provides a plurality of temporally spaced interrogating signals that include respective identifiers, each of the plurality of transponders including;

a receiver for receiving at least one of the interrogating signals;

a signal processor responsive to the receiver for identifier extraction; and

a transmitter responsive to an identifier for transmitting a response signal for allowing the RFID interrogator to determine an order in which the plurality of transponders were first in receipt of an interrogating signal.

5. The plurality of transponders according to claim 4 wherein the identifier includes first data indicative of the time of the provision of the interrogating signal and the response signal includes data derived from the identifier and data unique to a respective transponder.

6. The plurality of transponders according to claim 5 wherein the identifier also includes second data unique to the interrogator and the response signal is derived from the first data and the second data.

7. The plurality of transponders according to claim 4 wherein each of the plurality of transponders includes a respective memory array for storing selected data.

8. The plurality of transponders according to claim 7 wherein each transponder includes a power supply for supplying power to the transponder, inclusive of the memory array.

9. The plurality of transponders according to claim 8 wherein each memory array validly maintains the selected data for a predetermined time period after power ceases to be provided to the power supply.

10. The plurality of transponders according to claim 4 wherein the memory array comprises dynamic memory.

11. A method of using a plurality of radio-frequency identification (“

RFID”

) transponders with an RFID interrogator that provides a plurality of temporally spaced interrogating signals that include respective identifiers, the method including the steps of;

the RFID transponders receiving at least one of the plurality of temporally spaced interrogating signals with respective receivers;

being responsive to the respective receivers for extracting the identifiers from the at least one of the plurality of temporally spaced interrogating signals; and

transmitting respective response signals in response to the identifiers for allowing the interrogator to determine the order in which the plurality of RFID transponders were first in receipt of an interrogating signal.

12. A baggage handling system for baggage tagged with respective radio-frequency identification (“

RFID”

) transponders, the system including;

an RFID interrogator that transmits a plurality of temporally spaced interrogating signals into an interrogating space;

wherein the signals include respective identifiers;

a conveyer for sequentially progressing the baggage through the interrogating space;

a receiver for receiving response signals from the transponders;

wherein the response signals include identity data derived from at least one of the plurality of temporally spaced interrogating signals; and

a signal processor responsive to the receiver for extracting the identity data from the response signals for determining an order in which the baggage is progressed through the interrogating space.

13. The baggage handling system according to claim 12 including:

a plurality of spaced apart interrogators; and

wherein the identifiers include data indicative of an interrogator that transmitted a respective interrogating signal.

14. A method of handling baggage tagged with respective radio-frequency identification (“

RFID”

) transponders, the method including the steps of;

transmitting, by an RFID interrogator, a plurality of temporally spaced interrogating signals into an interrogating space;

wherein each of the plurality of temporally spaced interrogating signals includes a respective identifier;

sequentially progressing the baggage through the interrogating space;

receiving, by a receiver, response signals from the transponders;

wherein the response signals include identity data derived from at least one of the plurality of temporally spaced interrogating signals; and

being responsive to the receiver for extracting the identity data from the response signals for determining an order in which the baggage is progressed through the interrogating space.

15. The method according to claim 14 including the step of muting an RFID transponder once the RFID transponder has been interrogated.

16. The method according to claim 15 including the step of muting the RFID transponder only in respect of interrogation signals from a same interrogator.

17. The method according to claim 15 including the step of configuring an RFID interrogator to selectively un-mute the interrogated RFID transponder by providing an identifier that indicates to the RFID transponder that the second interrogator is not a previous RFID interrogator.