ANTENNA APPARATUS

• US 20120091821A1
• Filed: 10/20/2011
• Published: 04/19/2012
• Est. Priority Date: 04/21/2009
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: KATO, Noboru, TANIGUCHI, Katsumi, SASAKI, Jun, GOUCHI, Naoki
• Granted Patent: US 9,000,619 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: G06K 19/07779 the inductive antenna being a coil
• CPC Class Codes: H01P 11/00 Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
• CPC Class Codes: H01P 11/001 Manufacturing waveguides or transmission lines of the waveguide type
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• 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 1/2291 used in bluetooth or WI-FI devices of Wireless Local Area Networks [WLAN] H01Q1/241 takes precedence; WLAN in general H04W
• CPC Class Codes: H01Q 1/243 with built-in antennas
• 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
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 1/52 Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure absorbing means H01Q17/00
• CPC Class Codes: H01Q 19/02 Details fastening of an element on a boom H01Q1/1228
• CPC Class Codes: H01Q 19/062 for focusing
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 7/04 Screened antennas H01Q7/02, H01Q7/06 take precedence
• CPC Class Codes: H01Q 7/06 with core of ferromagnetic material H01Q7/02 takes precedence
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

There is provided an antenna apparatus. A magnetic flux passing through a coil aperture of an antenna coil passes through a conductor aperture of a conductive layer, but the magnetic flux does not pass through the conductive layer. Accordingly, the magnetic flux is diverted to a path in which the conductor aperture of the conductive layer is the inside and the outer edge of the conductive layer is the outside. As a result, the magnetic flux passing through the coil aperture of the antenna coil makes a relatively large loop and links the inside and the outside of a coil conductor in an antenna in a communication partner with the antenna apparatus.

Claims

1. An antenna apparatus comprising:

a coil conductor including a coil aperture at a winding center of the coil conductor;

a conductive layer including a conductor aperture and a slit for connecting the conductor aperture and an outer edge of the conductive layer; and

a radiation plate, and

wherein the coil conductor and the conductive layer are coupled to each other via an electromagnetic field, and

wherein the conductive layer and the radiation plate are coupled to each other via an electromagnetic field or a magnetic field.

2. The antenna apparatus according to claim 1, wherein the coil aperture and the conductor aperture at least partly overlap in plan view of the coil conductor.

3. The antenna apparatus according to claim 1, wherein the coil conductor and the conductive layer overlap in plan view of the coil conductor.

4. The antenna apparatus according to claim 2, wherein the coil conductor and the conductive layer overlap in plan view of the coil conductor.

5. The antenna apparatus according to claim 1, wherein the coil conductor and the conductive layer are disposed in close proximity to each other.

6. The antenna apparatus according to claim 1, wherein an area of the conductive layer is larger than that of a region where the coil conductor is formed.

7. The antenna apparatus according to claim 1, wherein the coil conductor is wound in a plurality of layers.

8. The antenna apparatus according to claim 1, wherein circumferences of the coil aperture and the conductor aperture almost overlap in plan view of the coil conductor.

9. The antenna apparatus according to claim 1, wherein the conductive layer is formed on an inner surface or an outer surface of a case of an electronic apparatus into which the antenna apparatus is incorporated.

10. The antenna apparatus according to claim 1, wherein the coil conductor is formed on a substrate, a magnetic sheet is laminated on one of surfaces of the substrate which is farther from an antenna in a communication partner than another surface of the substrate, and the substrate and the magnetic sheet form an antenna coil module.

11. The antenna apparatus according to claim 10, wherein the radiation plate faces the conductive layer, and the radiation plate partly overlaps the conductive layer in plan view of the radiation plate.

12. The antenna apparatus according to claim 1, wherein the conductive layer and the radiation plate are coupled via an electromagnetic field or a magnetic field.

13. The antenna apparatus according to claim 1, wherein the radiation place does not overlap the conductive layer in plan view of the radiation plate.

14. The antenna apparatus according to claim 1, wherein the coil conductor has one of a loop shape or a spiral shape.