Smart card with switchable matching antenna

• US 8,322,624 B2
• Filed: 08/25/2008
• Issued: 12/04/2012
• Est. Priority Date: 04/10/2007
• Status: Expired due to Fees

• Current Assignee: HID Global GmbH (Assa Abloy AB), Féinics AmaTech Teoranta (Paragon Group Limited)
• Original Assignee: Féinics AmaTech Teoranta (Paragon Group Limited)
• Inventors: Finn, David
• Primary Examiner(s): HESS, DANIEL A
• Application Number:
  US12/198,103
• Publication Number:
  US 20080308641A1
• Time in Patent Office: 1,562 Days
• Field of Search: 235/492, 340/10.1, 340/10.2
• US Class Current: 235/492
• 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 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: H01L 2224/78301 Capillary
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H04B 5/77 for interrogation

Abstract

A smart card having a multi-layer substrate; a transponder module disposed in a first layer of the multi-layer substrate; a first antenna disposed in the first layer of the multi-layer substrate; and a second antenna disposed in a second layer of the multi-layer substrate. A switch and a capacitor in series with the second antenna. The first antenna may be tuned to a different frequency than the second antenna. An RFID chip and antenna in a mold mass disposed in a recess in the first layer of a substrate, behind a hologram disposed on the first layer of the substrate. The switch for the second antenna disposed under the RFID chip. A layer of ferrite material disposed between the hologram and the RFID chip. LEDs disposed behind the hologram.

Claims

1. Smart card comprising:

a multi-layer substrate;

a transponder module comprising an RFID chip disposed in a first layer of the multi-layer substrate;

a first antenna disposed in the first layer of the multi-layer substrate and connected to the transponder module; and

a second antenna which is a coupling antenna disposed in a second layer of the multi-layer substrate which is underlying the first layer so that the second antenna is inductively coupled with the first antenna;

wherein the first and second antennas are not connected with one another, but rather are inductively coupled with one another; and

wherein the first antenna is tuned to a first frequency which is relatively far from a desired operating frequency for the RFID chip, and the second antenna is tuned to a frequency which is relatively close to the desired operating frequency.

2. The smart card of claim 1, further comprising:

a switch disposed in the second layer of the multi-layer substrate, for selectively connecting or disconnecting ends of the second antenna.

3. The smart card of claim 2, further comprising:

a capacitor disposed in the second layer of the multi-layer substrate, in series with an end of the second antenna.

4. The smart card of claim 2, wherein:

the switch is selected from the group consisting of a toggle switch, a slide switch, a QTC switch, a piezo film switch and a touch sensor switch.

5. The smart card of claim 1, wherein:

the first antenna is tuned to approximately 50 MHz, and the second antenna is tuned to approximately 14.5 MHz; and

the desired operating frequency is approximately 13.56 MHz.

6. The smart card of claim 1, wherein:

the first antenna comprises 1 turn of wire, and the second antenna comprises several turns of wire.

7. The smart card of claim 1, wherein:

the first antenna has a relatively low Q factor, and the second antenna has a relatively high Q factor.

8. The smart card of claim 1, wherein:

the first antenna has a relatively low inductivity, and the second antenna has a relatively high inductivity.

9. The smart card of claim 1, wherein:

the RFID chip is disposed in a recess in the first layer of the substrate.

10. The smart card of claim 1, wherein:

the RFID chip is disposed on a carrier.

11. The smart card of claim 1, wherein:

the first antenna is incorporated on the RFID chip.

12. The smart card of claim 1, wherein:

the chip is disposed in a mold mass.

13. The smart card of claim 1, further comprising:

a hologram disposed on the first layer of the substrate.

14. The smart card of claim 13, further comprising:

a layer of ferrite material disposed between the hologram and the RFID chip.

15. The smart card of claim 13, further comprising:

LEDs disposed behind the hologram.

16. The smart card of claim 1, further comprising:

a switch for switching the second antenna on and off, to control unauthorized access to the smart card;

wherein the switch is disposed under the RFID chip.