JP2002305408A - Antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna which is compact and can obtain superior radiation characteristics and gain. SOLUTION: A line-type conductor foil, whose one end is open, is disposed on a printed board 11; a loop-type conductor foil, whose one end is connected with ground, is disposed on the opposite surface of the printed board or on a surface which interposes an insulating layer on the line-type conductor foil surface; the other end of the line-type conductor foil is electrically connected with the other end of the loop-type conductor foil; and the antenna is disposed on the printed board, where the end of the electrically connected side is set as a feeding point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna of a wireless communication module which is incorporated in a white goods or the like and constructs a home communication network.

[0002]

2. Description of the Related Art Conventionally, an antenna provided on a printed circuit board has a loop-shaped antenna, a small dipole, or a zigzag pattern as shown in FIG. Was. In FIG. 4, reference numeral 1 denotes a printed board, reference numeral 2 denotes a shield plate, and reference numeral 3 denotes an antenna formed of copper foil on the printed board.

[0003]

However, the antenna of the above-mentioned conventional configuration cannot obtain a sufficient antenna gain when the antenna size is smaller than the wavelength, and when the antenna provided on the printed circuit board is used, the communication becomes difficult. There was a problem that the distance became short.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a structure in which a linear conductive foil having an open end is provided on a printed circuit board, and is opposite to the linear conductive foil surface of the printed circuit board. A loop-shaped conductor foil, one end of which is connected to the ground, is provided on the surface or the surface sandwiching the insulating layer with the linear conductor foil surface, and the other end of the linear conductor foil and the other of the loop-shaped conductor foil are provided. An antenna is provided on a printed circuit board, the end of which is electrically connected to a through hole, and the end on the through hole side is used as a feeding point.

According to the above invention, a good antenna gain can be obtained by a combination of a loop-shaped conductor foil and a linear conductor foil.

[0006]

An antenna according to a first aspect of the present invention is provided with a linear conductive foil having an open end on a printed circuit board, and a surface opposite to the linear conductive foil surface of the printed circuit board. A loop-shaped conductor foil having one end connected to the ground is provided on the surface between the linear conductor foil surface and the insulating layer, and the other end of the linear conductor foil and the other end of the loop-shaped conductor foil are provided. Are electrically connected by a through hole, and the end on the through hole side is used as a feeding point.

[0007] A good antenna gain can be obtained by the synergistic effect of the loop-shaped conductor foil and the linear conductor foil.

[0008] An antenna according to a second aspect of the present invention is characterized in that the linear conductive foil whose one end is open is arranged so as to be bent along the end surface of the printed circuit board. Then, a good antenna gain can be obtained by effectively using the printed circuit board surface.

The antenna according to a third aspect of the present invention is characterized in that a part of the loop-shaped conductor foil whose one end is connected to the ground is arranged in parallel with the linear conductor foil whose one end is open. I have. Then, the shape can be made smaller and a good antenna gain can be obtained.

[0010]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an antenna showing an embodiment of the present invention. In FIG. 1, 11 is a printed circuit board, 12 is a shield plate, and 13 and 14 are antennas made of copper foil on the printed circuit board. 15 is a through hole. The shield plate 12 is fixed on the printed board 11, and is connected to a circuit ground (hereinafter, referred to as GND). On the printed board 11, a GND and a circuit pattern are formed by copper foil, and circuit components are mounted. The shield plate 12 is attached so as to cover the circuit components. The circuit pattern formed on the printed circuit board 11 is a wireless circuit unit and a control unit that controls the wireless circuit. The control unit is constituted by a microcomputer. The antenna 13 is connected to a radio circuit mounted in the shield plate 12 with a copper foil. The antennas 13 and 14 are connected by a copper foil. By connecting the antenna 13 and the antenna 14 with a copper foil, the antenna 1 extends along the end surface of the printed circuit board 11.
The antenna is bent from 3 to the antenna 14.

FIG. 2 is a view of the back surface of the printed circuit board of FIG. However, FIG. 2 is a view in which the back surface is seen through from the front surface. In FIG. 2, reference numeral 21 denotes a printed circuit board, which shows the back surface of the printed circuit board 11. Reference numeral 22 denotes a shield plate disposed on the back surface of the printed circuit board 21. 23 and 2
4 is an antenna. Reference numeral 25 denotes a through hole, which is the same as the through hole 15 shown in FIG. Reference numeral 26 denotes a connection point between the antenna 23 and GND. Reference numeral 27 denotes a through hole, which connects the antenna 14 and the antenna 24 shown in FIG. On the printed circuit board 21, GND and a circuit pattern are formed by copper foil. The circuit components are not mounted on the back surface shown in FIG. The shield plate 22 is attached so as to cover the circuit pattern. Antenna 2
3 is connected to the antenna 13 of FIG. Another end of the antenna 23 is connected to GND at 26.

Antenna 13, Antenna 14, Antenna 2
3. One antenna is composed of the antenna 24. Here, the antennas 13, 14, and 24 are linear antennas, and the antenna 23 corresponds to a loop antenna. The antenna 13 and the antenna 23 are arranged in parallel on the front and back of the substrate as shown in FIGS.

As described above, the antenna of the present invention is provided with a linear conductor foil having one end open on a printed circuit board, and the surface opposite to the conductor foil of the printed circuit board or the surface of the linear conductor foil and an insulating layer. A loop-shaped conductor foil, one end of which is connected to the ground, is provided on the surface sandwiching it, and the other end of the linear conductor foil and the other end of the loop-shaped conductor foil are connected to each other with a through hole. The configuration is such that the end is a feeding point. And
A good antenna gain can be obtained.

Further, the antenna of the present invention is characterized in that the linear conductor foil having one open end is arranged so as to be bent along the end surface of the printed circuit board. Then, a good antenna gain can be obtained by effectively using the printed circuit board surface.

Further, the antenna of the present invention is characterized in that a part of the loop-shaped conductor foil whose one end is connected to the ground is arranged in parallel with the linear conductor foil whose one end is open. Then, the shape can be made smaller and a good antenna gain can be obtained.

FIG. 3 shows the characteristics of the antenna of this embodiment.
The characteristics shown in FIG. 3 are obtained by actually forming antennas having the shapes shown in FIGS. 1 and 2 on a printed circuit board and actually measuring the antenna characteristics. FIG. 3A shows radiation characteristics on a plane parallel to the ground when the antenna 13 is arranged perpendicular to the ground. In the figure, reference numeral 41 indicates the characteristic of vertical polarization, and reference numeral 42 indicates the characteristic of horizontal polarization. As is apparent from the figure, the antenna shows almost no directivity in vertical polarization, and has an antenna gain of -5d.
A good characteristic of Bd is realized. FIG. 3B shows radiation characteristics on a plane parallel to the ground when the antenna 14 is arranged perpendicular to the ground. In the figure, reference numeral 43 denotes the characteristic of vertical polarization, and reference numeral 44 denotes the characteristic of horizontal polarization. As is clear from the figure, the figure shows a figure-eight characteristic similar to that of a dipole antenna in horizontal polarization. As is clear from FIG. 3, in the antenna of this embodiment, the linear antenna 13 and the loop antenna 23 function as main antennas, and most of the energy is radiated from the antenna 13 and the antenna 23. The linear antenna 14 and the antenna 24 function as sub-antennas for assisting radiation of energy from the antennas 13 and 23.

In the embodiment shown in FIGS. 1 and 2, the antenna 14 and the antenna 24 are connected using the through hole 27.
7 can be abolished.

The antenna 13 and the antenna 23 are connected by a through hole 25, and the antenna 14 and the antenna 24 are connected by a through hole 27.
Instead of the through hole 27, an electrical connection may be made by another method. For example, there is a method of passing a lead wire through a connection hole and soldering at both ends.

Also, instead of arranging the antennas 14 and 24 on the printed circuit board 11, equivalent performance can be obtained by arranging them on the outer periphery of the printed circuit board using metal wires (or metal pieces). In this case, the metal wire (or metal piece) is connected to the antenna 13 by means such as soldering.

[0020]

As described above, when the configuration of the present invention is used, it has the same radiation characteristics as a dipole antenna,
An antenna having good antenna gain can be formed compactly on a printed circuit board.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a surface antenna showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of an antenna on a back surface showing the embodiment of the present invention.

3A is a characteristic diagram of the antenna 13 according to the embodiment of the present invention; FIG. 3B is a characteristic diagram of the antenna 14 according to the embodiment of the present invention;

FIG. 4 is a configuration diagram of a conventional antenna.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Printed circuit board 12 Shield board 13 Antenna 14 Antenna 15 Through hole 21 Printed board 22 Shield board 23 Antenna 24 Antenna 25 Through hole 26 Connection point of antenna 23 and GND 27 Through hole 41, 43 Vertical polarization characteristic diagram 42, 44 Horizontal Polarization characteristics

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masafumi Nakagawa 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 5J046 AA04 AA07 AB11 PA07 5J047 AA04 AA07 AB11 FD01

Claims (3)

[Claims] A linear conductor foil having one end open on a printed circuit board is provided, and an insulating layer is interposed between the surface of the printed circuit board opposite to the surface of the linear conductor foil or the surface of the linear conductor foil. A loop-shaped conductive foil having one end connected to the ground on the outer surface; electrically connecting the other end of the linear conductive foil to the other end of the loop-shaped conductive foil; An antenna provided on a printed circuit board with the end on the side that serves as the feed point. 2. The antenna according to claim 1, wherein the linear conductive foil whose one end is open is disposed so as to be bent along an end surface of the printed circuit board. 3. The antenna according to claim 1, wherein a part of the loop-shaped conductor foil whose one end is connected to the ground is arranged in parallel with the linear conductor foil whose one end is open.