Antenna-electrode structure and communication apparatus having the same

• US 6,614,401 B2
• Filed: 03/14/2002
• Issued: 09/02/2003
• Est. Priority Date: 04/02/2001
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Miyata, Akira, Ishihara, Takashi, Kawahata, Kazunari, Sato, Jin, Nagumo, Shoji, Onaka, Kengo
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US10/096,587
• Publication Number:
  US 20020140610A1
• Time in Patent Office: 537 Days
• Field of Search: 343/702, 343/700.MS, 343/846, 455/575
• US Class Current: 343/702
• 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 5/378 Combination of fed elements with parasitic elements
• CPC Class Codes: H01Q 9/0442 with particular tuning means

Abstract

An antenna-electrode structure includes a feeding radiant-electrode and a grounded portion arranged such that an open-end of the feeding radiant-electrode defines a capacitance to the grounded portion therebetween, and a non-feeding radiant-electrode arranged to electromagnetically couple the feeding radiant-electrode. The non-feeding radiant electrode is arranged such that an open-end thereof defines a capacitance to the grounded portion therebetween to produce a dual-frequency resonance state together with the feeding radiant-electrode. In response to a signal supplied from a signal-supply source, the feeding radiant-electrode performs an antenna action and the non-feeding radiant-electrode in turn performs an antenna action by signal transmission from the feeding radiant-electrode, such that by being excited from these actions, the grounded portion also performs an antenna action. Because of the antenna action of the grounded portion, the sizes of the feeding radiant-electrode and the non-feeding radiant electrode are reduced.

Claims

1. An antenna-electrode structure comprising:

a substrate;

a grounded portion provided on the substrate;

a non-grounded portion on which an antenna is mounted;

a feeding radiant-electrode into which a signal is supplied from a signal supply source;

a non-feeding radiant-electrode arranged adjacent to the feeding radiant electrode in a direction separated from the grounded portion via a space therebetween for producing a dual-frequency resonance state by electromagnetic coupling with the feeding radiant-electrode; and

a dielectric base substance surface-mounted on the substrate and having the feeding radiant-electrode mounted thereon;

wherein

one end of the feeding radiant-electrode is open so as to define a capacitance to the grounded portion therebetween; and

wherein the non-feeding radiant-electrode is provided on the dielectric base substance along the feeding radiant-electrode and one end of the non-feeding radiant-electrode is connected to the grounded portion while the other end is open, the open-end of the non-feeding radiant electrode defining a capacity-loaded electrode forming a capacitance to the grounded portion therebetween at a position close to a capacity portion located between the open-end of the feeding radiant-electrode and the grounded portion.

2. An antenna-electrode structure according to claim 1, further comprising an insulating member, wherein the feeding radiant-electrode and the non-feeding radiant-electrode are arranged with the insulating member provided therebetween.

3. An antenna-electrode structure according to claim 1, further comprising a feeding electrode electrically connected to the signal supply source, wherein the feeding radiant-electrode communicates and connects to the feeding electrode so as to define a directly-feeding-type feeding radiant-electrode in which a signal is directly supplied from the signal supply source via the feeding electrode.

4. An antenna-electrode structure according to claim 1, further comprising a feeding electrode electrically connected to the signal supply source, wherein the feeding radiant-electrode is provided in a position spaced from the feeding electrode so as to define a capacity-feeding-type feeding radiant-electrode in which a signal from the signal supply source is supplied by capacity coupling from the feeding electrode.

5. An antenna-electrode structure according to claim 1, wherein the substrate includes an overhang portion and said non-grounded portion is provided on the overhang portion of said substrate.

6. An antenna-electrode structure according to claim 1, wherein said substrate is a chip base-substrate.

7. A communication apparatus according to the present invention comprising an antenna-electrode structure according to claim 1.

8. A communication apparatus according to claim 7, wherein said communication apparatus is a portable telephone.

9. A communication apparatus according to claim 7, wherein said communication apparatus is a notebook personal computer.

10. A communication apparatus according to claim 7, wherein said communication apparatus is a personal digital assistant.

11. An antenna-electrode structure comprising:

a substrate;

a grounded portion provided on the substrate;

a non-grounded portion on which an antenna is mounted;

a feeding radiant-electrode into which a signal is supplied from a signal supply source and having a substantially U-shape;

a non-feeding radiant-electrode arranged adjacent to the feeding radiant electrode in a direction separated from the grounded portion via a space therebetween for producing a dual-frequency resonance state by electromagnetic coupling with the feeding radiant-electrode;

wherein

one end of the feeding radiant-electrode is open so as to define a capacitance to the grounded portion therebetween; and

wherein the non-feeding radiant-electrode is provided on the non-grounded portion along the feeding radiant-electrode and one end of the non-feeding radiant-electrode is connected to the grounded portion while the other end is open, the open-end of the non-feeding radiant electrode defining a capacity-loaded electrode forming a capacitance to the grounded portion therebetween at a position close to a capacity portion located between the open-end of the feeding radiant-electrode and the grounded portion.

12. An antenna-electrode structure according to claim 11, wherein the feeding radiant-electrode and the non-feeding radiant-electrode are directly located and pattern-formed on the non-grounded portion on the substrate.

13. An antenna-electrode structure according to claim 11, further comprising an insulating member, wherein the feeding radiant-electrode and the non-feeding radiant-electrode are arranged with the insulating member provided therebetween.

14. An antenna-electrode structure according to claim 11, further comprising a feeding electrode electrically connected to the signal supply source, wherein the feeding radiant-electrode communicates and connects to the feeding electrode so as to define a directly-feeding-type feeding radiant-electrode in which a signal is directly supplied from the signal supply source via the feeding electrode.

15. An antenna-electrode structure according to claim 11, further comprising a feeding electrode electrically connected to the signal supply source, wherein the feeding radiant-electrode is provided in a position spaced from the feeding electrode so as to define a capacity-feeding-type feeding radiant-electrode in which a signal from the signal supply source is supplied by capacity coupling from the feeding electrode.

16. An antenna-electrode structure according to claim 11, wherein the substrate includes an overhang portion and said non-grounded portion is provided on the overhang portion of said substrate includes.

17. An antenna-electrode structure according to claim 11, wherein said substrate is a chip base-substrate.

18. A communication apparatus according to the present invention comprising an antenna-electrode structure according to claim 11.

19. A communication apparatus according to claim 18, wherein said communication apparatus is a portable telephone.

20. A communication apparatus according to claim 18, wherein said communication apparatus is a notebook personal computer.

21. A communication apparatus according to claim 18, wherein said communication apparatus is a personal digital assistant.