Radio frequency identification (RFID) systems and methods

• US 20070241902A1
• Filed: 11/08/2006
• Published: 10/18/2007
• Est. Priority Date: 04/18/2006
• Status: Active Grant

• Current Assignee: Princeton Technology Corporation
• Original Assignee: Princeton Technology Corporation
• Inventors: Chang, Hwa-Hsiang
• Granted Patent: US 8,237,702 B2
• Time in Patent Office: Days
• US Class Current: 340/572.100
• CPC Class Codes: G08B 13/1427 with transmitter-receiver for distance detection
• CPC Class Codes: G08B 21/0227 System arrangements with a plurality of child units
• CPC Class Codes: G08B 21/023 Power management, e.g. system sleep and wake up provisions
• CPC Class Codes: G08B 21/0275 Electronic Article Surveillance [EAS] tag technology used for parent or child unit, e.g. same transmission technology, magnetic tag, RF tag, RFID

Abstract

A radio frequency identification (RFID) system comprises a reader, a memory, and a processor. When initiated, the reader receives an identification code of a first tag within a wireless communication range. The memory stores a time setting and an identification code of a second tag. The processor initiates the reader at a predetermined time indicated by the time setting, thus to determine whether the second tag exists in the wireless communication range.

Claims

1. A radio frequency identification (RFID) system, comprising:

a reader, when initiated, receiving an identification code of a first tag within a wireless communication range;

a memory storing a time setting and an identification code of a second tag; and

a processor initiating the reader at a predetermined time indicated by the time setting, thus determining whether the second tag exists in the wireless communication range.

2. The system as claimed in claim 1, wherein the time setting indicates a cycle, wherein the processor periodically initiates the reader to determine once for each cycle whether the second tag exists in the wireless communication range.

3. The system as claimed in claim 1, wherein the time setting indicates a plurality of sessions in a schedule, each session corresponds to identification codes of a plurality tags respectively attached to a plurality of objects, further comprising:

a clock, wherein when the clock reaches the beginning of a session, the processor initiates the reader to determine whether the tags attached to the objects exist in the wireless communication range.

4. The system as claimed in claim 1, further comprising:

a power supply supplying electrical power to the RFID system, wherein the power supply, the reader, the memory, and the processor are disposed in a case to form a portable device.

5. The system as claimed in claim 4, further comprising:

an input device, when operated, initiating the reader.

6. The system as claimed in claim 4, wherein the power supply comprises a solar panel or a power generator.

7. The system as claimed in claim 4, wherein the portable device comprises a personal digital assistant (PDA) or a mobile phone.

8. The system as claimed in claim 1, wherein, when the second tag does not exist in the wireless communication range, the processor directs an audio alert to be output.

9. The system as claimed in claim 1, further comprising:

a display, wherein, when the second tag does not exist in the wireless communication range, the processor displays a message on the display.

10. A radio frequency identification (RFID) system, comprising:

a reader, when initiated, receiving an identification code of a first tag within a wireless communication range;

a memory storing an identification code of a second tag;

an inertial motion sensor detecting motion of the RFID system; and

a processor initiating the reader based on the motion detection by the inertial motion sensor to determine whether the second tag exists in the wireless communication range.

11. The system as claimed in claim 10, wherein the inertial motion sensor comprises a pedometer, and when the number counted by the pedometer increases to a predetermined value, triggers the reader to be initiated.

12. The system as claimed in claim 10, further comprising:

a power supply supplying electrical power to the RFID system, wherein the power supply, the reader, the memory, and the processor are disposed in a case to form a portable device.

13. The system as claimed in claim 12, wherein the power supply comprises a solar panel or a power generator.

14. The system as claimed in claim 10, wherein, when the second tag does not exist in the wireless communication range, the processor directs an audio alert to be output.

15. The system as claimed in claim 10, further comprising:

a display, wherein, when the second tag does not exist in the wireless communication range, the processor displays a message on the display.

16. A radio frequency identification (RFID) method, implemented in an RFID system, comprising:

storing a time setting and an identification code of a first tag in the RFID system;

initiating a reader of the RFID system on a predetermined time indicated by the time setting;

receiving an identification code of a second tag within a wireless communication range of the reader;

comparing the identification codes of the first and the second tags to determine whether the first tag exists in the wireless communication range.

17. The method as claimed in claim 16, wherein the time setting indicates a cycle, wherein the reader is periodically initiated once for each cycle to determine whether the first tag exists in the wireless communication range.

18. The method as claimed in claim 16, wherein the time setting indicates a plurality of sessions in a schedule, each session corresponds to identification codes of a plurality of tags respectively attached to a plurality of objects, further comprising when a clock of the RFID system reaches the beginning of a session, initiating the reader to determine whether the tags attached to the objects exist in the wireless communication range.

19. The method as claimed in claim 16, wherein, when the first tag does not exist in the wireless communication range, outputting an audio alert.

20. The method as claimed in claim 16, wherein, when the first tag does not exist in the wireless communication range, displaying a message on a display of the RFID system.