Multiple feed point slot antenna

• US 20020177408A1
• Filed: 04/18/2002
• Published: 11/28/2002
• Est. Priority Date: 03/25/2000
• Status: Active Grant

• Current Assignee: Mineral Lassen LLC (Intellectual Ventures LLC)
• Original Assignee: Mineral Lassen LLC (Intellectual Ventures LLC)
• Inventors: Forster, Ian J., Horrell, Peter Robert George
• Granted Patent: US 6,985,119 B2
• Time in Patent Office: Days
• US Class Current: 455/41.1
• CPC Class Codes: B65D 2203/10 Transponders
• CPC Class Codes: B65D 25/205 Means for the attachment of labels, cards, coupons or the like; cards or coupons for the other types of rigid or semi-rigid containers B65D25/36 takes precedence
• CPC Class Codes: G06K 19/041 Constructional details G06K19/06 takes precedence
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/44 using equipment having another main function to serve additionally as an antenna , e.g. means for giving an antenna an aesthetic aspectH01Q1/27 - H01Q1/34 take precedence
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 13/12 Longitudinally slotted cylinder antennas; Equivalent structures
• CPC Class Codes: H01Q 13/18 the slot being backed by, or formed in boundary wall of, a resonant cavity longitudinally slotted cylinder H01Q13/12 ; Open cavity antennas

Abstract

A wireless communication device and method for identifying a container, or communication information about a container using a slot in the container as an antenna. The device includes a wireless communication device for transmitting information regarding the container. The container includes an outer wall forming rim and a slot between the rim edge and the outer wall that is circular and continues without boundaries. The wireless communication device is coupled to the slot to provide the slot antenna for communications. An impedance matching network is additionally provided to make the operating frequency of the slot substantially the same as the operating frequency of the wireless communication device. Alternatively, shorting posts may be placed in the slot to define boundaries of the slot to match the operating frequency of the slot to the operating frequency of the antenna. Multiple feed points may be provided between the wireless communication device and the slot.

Claims

1. A device for identifying a container having a slot, comprising:

a wireless communication device mounted on the container to communicate information associated with the container wirelessly; and

a slot antenna formed by electronically associating said wireless communication device to the slot, said slot antenna including a plurality of feed points coupling said wireless communication device to said slot.

2. The device of claim 1 further comprising a transmission line electrically connecting said wireless communication device to said plurality of feed points.

3. The device of claim 1 further comprising a plurality of transmission lines, each of said plurality of transmission lines electrically connecting different ones of said plurality of feed points to said wireless communication device.

4. The device of claim 2 wherein said transmission line is a coaxial cable.

5. The device of claim 2 wherein said transmission line is a twisted pair.

6. The device of claim 2 wherein said transmission line is a micro-strip transmission line.

7. The device of claim 1 wherein each of said plurality of feed points includes a rectifier.

8. The device of claim 1 wherein said plurality of feed points are positioned such that reflections between different ones of said plurality of feed points and said transponder cancel.

9. The device of claim 1 wherein said plurality of feed points enables multi-frequency reception by said wireless communication device.

10. The device of claim 1 further including a micro-strip transmission line electrically connecting said plurality of feed points to said wireless communication device.

11. The device of claim 10 wherein said micro-strip transmission line includes at least one electronic component incorporated thereinto.

14. The method of claim 13 further comprising interrogating said wireless communication device at a plurality of frequencies.

15. The method of claim 13 further comprising positioning a transmission line proximate said slot to connect electrically each of said plurality of feed points with said wireless communication device.

16. The method of claim 15 further comprising integrating electronic components on said transmission line.

18. The container of claim 17 wherein said slot antenna operates at a plurality of frequencies.

19. The container of claim 17 wherein reflections between said wireless communication device and each of said plurality of feed points cancel.

20. The container of claim 17 wherein said transmission line is held within said rim by a spring clip.

21. The container of claim 17 wherein said transmission line is a coaxial cable.

22. The container of claim 17 wherein said transmission line is a micro-strip transmission line.

23. The container of claim 22 wherein said micro-strip transmission line includes at least one electronic component integrated thereinto.

24. The container of claim 23 wherein said at least one electronic component comprises an impedance matching network.

25. The container of claim 23 wherein said at least one electronic component comprises a filter.

26. The container of claim 23 wherein said at least one electronic component comprises a coupler.

27. The container of claim 17 further comprising at least one rectifier, said rectifier operatively connected to said transmission line.

28. The container of claim 17 wherein said slot is formed by a curl in container to form a rim.

29. The container of claim 17 wherein said slot is formed by at least two pieces of conductive material in proximity to one another.

30. The container of claim 17 wherein said slot is formed by an area of free space contained on a conductive surface.

12. A system for identifying a container, comprising:

a container having a slot;

a wireless communication device mounted on the container to remotely communicate information associated with the container;

a slot antenna formed by electronically associating said wireless communication device to said slot said slot antenna including a plurality of feed points coupling said wireless communication device to said slot.

13. A method of using a slot on a container as an antenna, comprising:

associating a wireless communication device with the container;

positioning a plurality of feed points within the slot and electrically connected to said wireless communication device; and

communicating monitoring information associated with the container between said wireless communication device and an interrogation reader through a slot antenna formed by the slot within the container.

17. A container comprising:

a slot;

a wireless communication device positioned contiguous said rim;

a transmission line electrically connected to said wireless communication device; and

a plurality of feed points electrically connecting said transmission line at different points to said slot such that said slot operates as a slot antenna.