Wireless Tag And Method For Producing Wireless Tag

• US 20100097191A1
• Filed: 12/29/2009
• Published: 04/22/2010
• Est. Priority Date: 07/18/2007
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: KAI, Manabu, MANIWA, Toru, YAMAGAJO, Takashi
• Granted Patent: US 8,493,183 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• 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 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142

Abstract

The wireless tag includes an antenna conductor; a first power-supply conductor which is electromagnetic-inductively coupled with the antenna conductor; and a second power-supply conductor which is loop-shaped and which is electrically coupled with the first power-supply conductor.

Claims

1. A wireless tag comprising:

an antenna conductor;

a first power-supply conductor which is electromagnetic-inductively coupled with the antenna conductor; and

a second power-supply conductor which is loop-shaped and which is electrically coupled with the first power-supply conductor.

2. The wireless tag according to claim 1, wherein the first power-supply conductor has a form of a dipole antenna or a monopole antenna.

3. The wireless tag according to claim 1, wherein the antenna conductor, the first power-supply conductor, and the second power-supply conductor are arranged at a first surface of a dielectric substrate.

4. The wireless tag according to claim 1, wherein

the antenna conductor is arranged at a first surface of a dielectric substrate;

and

the first power-supply conductor and the second power-supply conductor are arranged at a second surface of the dielectric substrate.

5. The wireless tag according to claim 1, further comprising a reinforcement member which covers the first power-supply conductor and the second power-supply conductor in avoidance of the antenna conductor.

6. The wireless tag according to claim 1, wherein the electrical length of a part of the first power-supply conductor which part is electromagnetic-inductively coupled with the antenna conductor is set to be equal to or less than the half of a wavelength of a signal transceived by the antenna conductor.

7. The wireless tag according to claim 1, wherein the electrical length of the second power-supply conductor is shorter than a wavelength of a signal transceived by the antenna conductor.

8. A method for producing a wireless tag, the method comprising:

forming an antenna conductor;

forming a first power-supply conductor which is electromagnetic-inductively coupled with the antenna conductor; and

forming a second power-supply conductor which is loop-shaped and which is electrically coupled with the first power-supply conductor.

9. The method according to claim 8, wherein impedance matching between the antenna conductor and an integrated circuit, with which the first power-supply conductor and the second power-supply conductor are electrically coupled, is controlled by varying an electrical length of a part of the first power-supply conductor which part is electromagnetic-inductively coupled with the antenna conductor.

10. The method according to claim 8, wherein impedance matching between the antenna conductor and an integrated circuit, with which the first power-supply conductor and the second power-supply conductor are electrically coupled, is controlled by varying an electrical length of the second power-supply conductor.