Antenna and RFID tag

• US 20070200782A1
• Filed: 10/27/2006
• Published: 08/30/2007
• Est. Priority Date: 02/24/2006
• Status: Active Grant

• Current Assignee: Omron Corporation
• Original Assignee: Omron Corporation
• Inventors: Saito, Keisuke, Hayama, Kosuke
• Granted Patent: US 7,339,550 B2
• Time in Patent Office: Days
• US Class Current: 343/795
• 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 1/38 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
• CPC Class Codes: H01Q 9/24 Shunt feed arrangements to single active elements, e.g. for delta matching
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

An antenna for an RFID tag includes each power feeding parts 11 that is formed of a conductor, meandering parts 13a and 13b that are formed of conductors shaped as a pair of meandering lines, connected to the power feeding parts 11, and extend from the power feeding parts 11 toward both ends of the power feeding parts 11, respectively, a pair of radiating parts 14a and 14b that are formed of conductors and connected to outer ends of the pair of meandering parts 13a and 13b, respectively. The meandering parts 13a and 13b include a plurality of sides arranged in a longitudinal direction where the meandering parts 13a and 13b extend. Further, the lengths of portions, where the ends of the radiating parts 14a and 14b facing the meandering parts 13a and 13b face the sides closest to the radiating parts 14a and 14b among the plurality of sides of the meandering parts 13a and 13b in a direction orthogonal to the longitudinal direction, are smaller than the widths of the widest portions of the radiating parts.

Claims

1. An antenna for an RFID (Radio Frequency Identification) tag, comprising:

a power feeding part formed of conductor;

meandering parts that are connected to the power feeding part and extend from the power feeding part toward both ends of the power feeding part, respectively, the meandering parts being formed of conductors shaped as a pair of meandering lines; and

a pair of radiating parts that are formed of conductors and connected to outer ends of the pair of meandering parts, respectively,

wherein the meandering parts include a plurality of sides arranged in a longitudinal direction where the meandering parts extend, and

the length of portions, where ends of the radiating parts facing the meandering parts face the sides closest to the radiating parts among the plurality of sides of the meandering parts in a direction orthogonal to the longitudinal direction, are smaller than the widths of the widest portions of the radiating parts.

2. The antenna according to claim 1,

wherein the widths of the ends of the radiating parts facing the meandering parts are smaller than the widths of the widest portions of the radiating parts, and

the lengths of the sides closest to the radiating parts among the plurality of sides of the meandering parts in the direction orthogonal to the longitudinal direction are smaller than the widths of the ends of the radiating parts facing the meandering parts.

3. The antenna according to claim 1,

wherein the widths of the portions of the radiating parts facing the meandering parts decrease as coming close to the meandering parts.

4. The antenna according to claim 1,

wherein the lengths of two or more sides, facing the radiating parts, among the plurality of sides of the meandering parts in the direction orthogonal to the longitudinal direction decrease as coming close to the radiating parts.

5. The antenna according to claim 1, further comprising:

a matching circuit that is connected to the power feeding part.

6. The antenna according to claim 1,

wherein the plurality of sides extend in the direction orthogonal to the longitudinal direction.

7. The antenna according to claim 1, wherein the antenna is an antenna for UHF band, and

the antenna has a size equal to or smaller than a size of 25×

100 mm.

8. An RFID tag comprising:

the antenna according to claim 1;

an integrated circuit that is connected to the power feeding part of the antenna; and

a dielectric substrate on which the antenna is disposed.