Antenna device and communication terminal device

Patent metadata

Field	Value
Publication number	US-9748634-B2
Application number	US-201414219172-A
Country	US
Kind code	B2
Filing date	Mar 19, 2014
Priority date	Jun 28, 2012
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

An antenna device includes a first conductor plane and a second conductor plane that face each other. The first conductor plane and the second conductor plane are electrically continuous through a first connection conductor, a second connection conductor, and a chip capacitor. A power feed coil is disposed between the first conductor plane and the second conductor plane. The power feed coil includes a magnetic core and a coil conductor. The coil conductor defines a pattern such that the coil conductor winds around the magnetic core. The power feed coil is disposed at a position closer to the first connection conductor and magnetically couples with the first connection conductor.

First claim

What is claimed is:

1. Electronic equipment comprising:
a casing including a conductor portion;
an antenna device; and
a plurality of conductive members; wherein
the plurality of conductive members include the conductor portion of the casing of the electronic equipment;
the antenna device includes:
a connection conductor that connects the plurality of conductive members;
a capacitor that defines a looped current path with the plurality of conductive members and the connection conductor, and that defines a resonant circuit with inductance components of the plurality of conductive members including the conductor portion of the casing and the connection conductor; and
a power feed coil that magnetically couples with the connection conductor;

a RFIC is provided inside the casing of the electronic equipment; and
a current of the looped current path flows through at least the plurality of conductive members and the connection conductor.

2. The electronic equipment according to claim 1 , wherein a resonant frequency of the resonant circuit is in a carrier frequency band of communication signals or adjacent to the carrier frequency band.

3. The electronic equipment according to claim 1 , wherein the plurality of conductive members include a ground conductor located on a circuit board.

4. The electronic equipment according to claim 1 , wherein the plurality of conductive members include a plurality of conductor planes.

5. The electronic equipment according to claim 1 , wherein the plurality of conductive members include a metal member disposed inside the casing of the electronic equipment.

6. The electronic equipment according to claim 1 , wherein
the plurality of conductive members include a ground conductor located on a circuit board of the electronic equipment; and
the connection conductor is a ground connection pin connecting the ground conductor and the conductor portion of the casing.

7. The electronic equipment according to claim 1 , wherein
the plurality of conductive members include a first conductor plane and a second conductor plane that face each other; and
the connection conductor includes a first connection conductor directly connecting the first conductor plane and the second conductor plane, and a second connection conductor connecting the first conductor plane and the second conductor plane through the capacitor.

8. The electronic equipment according to claim 4 , wherein
the plurality of conductive members include circuit boards; and
the connection conductor is a connector that connects the circuit boards.

9. The electronic equipment according to claim 1 , wherein
the capacitor is mounted on a circuit board; and
the connection conductor is the capacitor.

10. The electronic equipment according to claim 1 , wherein the power feed coil is mounted on a circuit board.

11. The electronic equipment according to claim 1 , wherein the power feed coil includes a multilayer structure in which a plurality of insulator layers, on which conductors defining an inductor are provided, and a plurality of insulator layers, on which conductors defining the capacitor are provided, are stacked.

12. The electronic equipment according to claim 10 , wherein the power feed coil and at least a portion of the connection conductor are integrated into a single component.

13. The electronic equipment according to claim 12 , wherein the connection conductor is a coil shaped and magnetically couples with the power feed coil.

14. The electronic equipment according to claim 12 , wherein the capacitor is incorporated in the single component.

15. The electronic equipment according to claim 12 , wherein the RFIC is incorporated in the single component and connected to the power feed coil.

16. The electronic equipment according to claim 6 , wherein
the carrier frequency of communication signals is a HF band frequency; and
the capacitor is an element that becomes inductive at a frequency equal to or above a UHF band.

17. A communication terminal device including an antenna device and a power feed circuit connected to the antenna device, the communication terminal device comprising:
a plurality of conductive members; and
a connection conductor that connects the plurality of conductive members; wherein
the plurality of conductive members include the conductor portion of the casing of the electronic equipment;
the antenna device includes:
a capacitor that defines a looped current path with the plurality of conductive members and the connection conductor, and that defines a resonant circuit with inductance components of the plurality of conductive members including the conductor portion of the casing and the connection conductor; and
a power feed coil that magnetically couples with the connection conductor;

a RFIC is provided inside the casing of the communication terminal device; and
a current of the looped current path flows through at least the plurality of conductive members and the connection conductor.

Assignees

• Murata Manufacturing Co

Inventors

• Nakano Shinichi
• Yosui Kuniaki
• Kato Noboru

Classifications

• H01Q9/0407

  Substantially flat resonant element parallel to ground plane, e.g. patch antenna (dipole H01Q9/285; monopole H01Q9/40) · CPC title

• G06K19/07794

  the record carrier comprising a booster or auxiliary antenna in addition to the antenna connected directly to the integrated circuit · CPC title

• H01Q9/045

  with particular feeding means (for circular polarisation H01Q9/0428) · CPC title

• H01Q7/00

  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 title

• H01Q1/521

  reducing the coupling between adjacent antennas · CPC title