Antenna device and communication terminal apparatus

• US 9,166,291 B2
• Filed: 02/07/2013
• Issued: 10/20/2015
• Est. Priority Date: 10/12/2010
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kato, Noboru, Sasaki, Jun, Ishino, Satoshi
• Primary Examiner(s): Karacsony, Robert
• Application Number:
  US13/761,195
• Publication Number:
  US 20130147675A1
• Time in Patent Office: 985 Days
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H01L 2924/19106 in a mirrored arrangement on two different side of a common die mounting substrate
• CPC Class Codes: H01Q 1/243 with built-in antennas
• 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 1/40 Radiating elements coated with or embedded in protective material
• CPC Class Codes: H01Q 7/06 with core of ferromagnetic material H01Q7/02 takes precedence
• CPC Class Codes: H01Q 9/27 Spiral antennas

Abstract

An antenna device includes an antenna coil including a first conductive pattern disposed on a first major surface of a magnetic sheet, a second conductive pattern disposed on a first major surface of a non-magnetic sheet, and an interlayer conductor connecting the first conductive pattern and second conductive pattern. The antenna coil including the first conductive pattern and second conductive pattern defines a spiral or substantially spiral pattern. The antenna device is a resin multilayer structure in which its base body is a laminate of the magnetic layer and non-magnetic layer and the predetermined patterns are disposed inside and outside the laminate.

Claims

1. An antenna device comprising:

a plurality of layers including at least a magnetic layer;

at least one first conductive pattern having a half-loop shape or a linear shape, including one or more layers, and being adjacent to a first major surface of the magnetic layer;

at least one second conductive pattern having a half-loop shape or a linear shape, including one or more layers, and being adjacent to a second major surface of the magnetic layer;

an interlayer conductor included in the plurality of layers and connecting the first conductive pattern and the second conductive pattern; and

an antenna coil including one turn or a plurality of turns, and including the at least one first conductive pattern, the at least one second conductive pattern, and the interlayer conductor, wherein

the plurality of layers includes one or more non-magnetic layers adjacent to the first major surface of the magnetic layer and a plurality of non-magnetic layers adjacent to the second major surface of the magnetic layer, the first conductive pattern is disposed on the magnetic layer and the non-magnetic layer adjacent to the first major surface of the magnetic layer, and the second conductive pattern is disposed on the non-magnetic layer adjacent to the second major surface of the magnetic layer.

2. The antenna device according to claim 1, wherein at least a portion of the at least one first conductive pattern is disposed on the first major surface of the magnetic layer, at least a portion of the second conductive pattern is disposed on a first major surface of a non-magnetic layer, and the first major surface of the non-magnetic layer is in contact with the second major surface of the magnetic layer.

3. The antenna device according to claim 1, wherein each of the at least one first conductive pattern and the at least one second conductive pattern includes a plurality of half-loop or linear conductive patterns being parallel or substantially parallel with each other, each of the conductive patterns is disposed on a plane, and the antenna coil defines a spiral when seen from a winding axis direction thereof.

4. The antenna device according to claim 1, wherein the plurality of layers includes a plurality of magnetic layers, and at least one of the at least one first conductive pattern and the at least one second conductive pattern is disposed on the plurality of magnetic layers.

5. The antenna device according to claim 1, further comprising a coupling conductor disposed within a loop defined by the at least one first conductive pattern and the at least one second conductive pattern when seen in plan view on any one of the plurality of layers, the coupling conductor being electrically coupled to an external ground terminal and isolated from the antenna coil.

6. The antenna device according to claim 1, wherein the first conductive pattern and the second conductive pattern have different line lengths.

7. The antenna device according to claim 1, wherein the antenna coil defines a spiral or substantially spiral pattern including a plurality of turns.

8. The antenna device according to claim 7, wherein the spiral or substantially spiral pattern of the antenna coil is a rectangular or substantially rectangular spiral pattern.

9. The antenna device according to claim 1, further comprising an additional magnetic layer stacked on the at least one first conductive pattern on the first major surface of the magnetic layer so as to cover a portion of the at least one first conductive pattern.

10. The antenna device according to claim 9, further comprising a first input/output terminal located at one end of the antenna coil and a second input/output terminal located at another end of the antenna coil, wherein the first and second input/output terminals are exposed from the antenna device.

11. The antenna device according to claim 1, wherein the at least one first and second conductive patterns define a helical or substantially helical antenna coil.

12. The antenna device according to claim 1, wherein:

the at least one first conductive pattern and the at least one second conductive pattern define a helical or substantially helical antenna coil, and

each of the at least one first conductive pattern and the at least one second conductive pattern includes a plurality of half-loop conductive patterns disposed on respective ones of the plurality of magnetic layers.

13. The antenna device according to claim 12, wherein the at least one first conductive pattern is disposed on one of the plurality of magnetic layers, and the at least one second conductive pattern is disposed on another of the plurality of magnetic layers.

14. The antenna device according to claim 12, wherein one of the plurality of non-magnetic layers is arranged at a lowermost position of the plurality of layers, a coupling conductor is disposed on a first major surface of the one of the plurality of non-magnetic layers disposed at the lowermost position, and input/output terminals and ground terminals are disposed on a second major surface of the one of the plurality of non-magnetic layers disposed at the lowermost position.

15. The antenna device according to claim 12, wherein at least two first conductive patterns and at least two second conductive patterns are provided and arranged to define a spiral or substantially spiral antenna coil including at least two turns between input/output terminals.

16. A communication terminal apparatus comprising:

an antenna device;

a communication circuit connected to the antenna device; and

a casing that houses the antenna device and the communication circuit;

the antenna device including;

a plurality of layers including at least a magnetic layer;

at least one first conductive pattern having a half-loop shape and being adjacent to a first major surface of the magnetic layer;

at least one second conductive pattern having a half-loop shape and being adjacent to a second major surface of the magnetic layer;

an interlayer conductor disposed in the plurality of layers and connecting the at least one first conductive pattern and the at least one second conductive pattern; and

an antenna coil including one turn or a plurality of turns, the antenna coil including the at least one first conductive pattern, the at least one second conductive pattern, and the interlayer conductor, wherein

the plurality of layers includes one or more non-magnetic layers adjacent to the first major surface of the magnetic layer and a plurality of non-magnetic layers adjacent to the second major surface of the magnetic layer, the first conductive pattern is disposed on the magnetic layer and the non-magnetic layer adjacent to the first major surface of the magnetic layer, and the second conductive pattern is disposed on the non-magnetic layer adjacent to the second major surface of the magnetic layer.

17. The communication terminal apparatus according to claim 16, wherein the casing includes an end portion directed toward a communication partner, and the antenna device is located in an area of the end portion of the casing.

18. The communication terminal apparatus according to claim 16, wherein a path length of the first conductive pattern is longer than a path length of the second conductive pattern, and the antenna device is arranged such that a side adjacent to the first conductive pattern is directed toward an antenna of a communication partner.

19. The communication terminal apparatus according to claim 16, wherein the communication terminal apparatus is a cellular telephone.

20. An antenna device comprising:

a plurality of layers including at least a magnetic layer;

at least one first conductive pattern having a half-loop shape or a linear shape, including one or more layers, and being adjacent to a first major surface of the magnetic layer;

at least one second conductive pattern having a half-loop shape or a linear shape, including one or more layers, and being adjacent to a second major surface of the magnetic layer;

an interlayer conductor included in the plurality of layers and connecting the first conductive pattern and the second conductive pattern;

an antenna coil including one turn or a plurality of turns, and including the at least one first conductive pattern, the at least one second conductive pattern, and the interlayer conductor; and

a coupling conductor disposed within a loop defined by the at least one first conductive pattern and the at least one second conductive pattern when seen in plan view on any one of the plurality of layers, the coupling conductor being electrically coupled to an external ground terminal and isolated from the antenna coil.

21. A communication terminal apparatus comprising:

an antenna device;

a communication circuit connected to the antenna device; and

a casing that houses the antenna device and the communication circuit;

the antenna device including;

a plurality of layers including at least a magnetic layer;

at least one first conductive pattern having a half-loop shape and being adjacent to a first major surface of the magnetic layer;

at least one second conductive pattern having a half-loop shape and being adjacent to a second major surface of the magnetic layer;

an interlayer conductor disposed in the plurality of layers and connecting the at least one first conductive pattern and the at least one second conductive pattern;

an antenna coil including one turn or a plurality of turns, the antenna coil including the at least one first conductive pattern, the at least one second conductive pattern, and the interlayer conductor; and

a coupling conductor disposed within a loop defined by the at least one first conductive pattern and the at least one second conductive pattern when seen in plan view on any one of the plurality of layers, the coupling conductor being electrically coupled to an external ground terminal and isolated from the antenna coil.