JP3331852B2 - Method of mounting surface mount antenna on substrate and communication device equipped with this substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication device such as a cellular phone, a method of mounting a surface mount antenna used for a wireless LAN (Local Area Network) on a substrate, and a communication device having the mounting substrate mounted thereon. .

[0002]

Aspects of the Related Art Mounting of a substrate of a conventional surface mount antenna will be described with reference the perspective view of FIG. 10, the enlarged side form view of FIG. 11. In both figures, 2
Reference numeral 0 denotes a board (mounting board) , and a surface mounting antenna 30 is mounted on one end 21 of one main surface of the board 20. The surface mount antenna 30 is shaped as shown in FIG. 12. In the figure, reference numeral 31 denotes a rectangular base, on the surface of which a radiation electrode 32 is formed. One end of the radiation electrode 32 extends to the vicinity of one side to form an open end 32a, and the other end is connected to a ground electrode 35 formed on the back surface via an end surface 31a facing the one side. ing. An excitation electrode 34 is formed on the other end surface 31b on the extension of the open end 32a, and a gap g is provided between the open end 32a and the edge of the excitation electrode 34. The excitation electrode 34 extends to the back surface of the base 31, and is electrically insulated from the ground electrode 35 by the base. Then, the excitation electrode 34 and the radiation electrode 32 are electromagnetically coupled by the capacitance formed in the gap g.

[0003]

However, in the conventional mounting method of the surface-mount antenna on the substrate, the open end 32a of the radiation electrode 32 of the surface-mount antenna 30 is not used.
That is, as excitation electrodes 34 faces the proximal end face 22 toward the substrate 20, since the surface mount antenna 30 is mounted in place on the substrate 20, as indicated by a dotted arrow in FIG. 11,
The excitation electric field of the excitation electrode 34 goes around to the ground electrode 23 via the end face 22 side of the substrate 20, and the radiation electrode 32
The electric field supposed to be transmitted to the antenna was reduced, and the gain was reduced. Also, in a communication device equipped with such a mounting board, the gain is similarly reduced.

Accordingly, an object of the present invention is to provide a method of mounting a surface mount antenna on a substrate capable of effectively supplying an excitation electric field to a radiation electrode, and a communication device equipped with the mount substrate.

[0005]

According to the present invention, in order to achieve the above object, a rectangular substrate and at least a surface of the substrate are provided.
A radiation electrode formed on the surface, and a radiation electrode formed on the back surface of the base.
Ground electrode and at least one end face of the substrate
And an excitation electrode formed continuously on the back
The radiation electrode has an open end at one end and the ground at the other end.
One end of the excitation electrode is connected to the excitation electrode.
Formed opposite to the open end of the radiation electrode with a gap
And a table in which the radiation electrode and the excitation electrode are electromagnetically coupled.
A surface mount antenna that mounts a surface mount antenna on a substrate
A method of mounting on a substrate, wherein the surface-mounted antenna
Together implement until the center from one end portion of one major surface of the substrate to the open end side of the radiation electrode of the surface mount antenna, the one end portion of the one main surface of the substrate A method of mounting a surface-mounted antenna on a substrate, wherein the surface-mounted antenna is mounted on the substrate so as to face the direction of the other end facing the substrate.

Further, the present invention is a communication device comprising a substrate on which a surface mount antenna is mounted by the mounting method.

As described above, according to the present invention, when mounting a surface mount antenna from one end to the center of one main surface of a substrate, the open end side of the surface mount antenna, Since the surface mount antenna is mounted on the substrate such that the electrode side faces the other end opposite to one end of the one main surface of the substrate, the excitation electromagnetic field from the excitation electrode is It does not go around to the ground electrode on the back surface of the substrate via the end surface near the substrate, so that a decrease in gain can be prevented.

[0008] In a communication device equipped with a surface-mounted antenna mounting board mounted as described above, a decrease in gain can be similarly prevented.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view for explaining a method of mounting a surface mount antenna on a substrate, and FIG. 2 is a partially enlarged side view of FIG. In both figures, 10 is the substrate (actual
Board 1 ), one end 1 of one main surface of the board 10
1, a surface-mounted antenna 1 is mounted. This surface-mounted antenna 1 has a shape as shown in FIG. In the figure, reference numeral 2 denotes a rectangular base made of a dielectric or magnetic material such as ceramics or resin, on the surface of which a strip line-shaped radiation electrode 3 having a length of about λ / 4 is formed. One end of the radiation electrode 3 extends to the vicinity of one side to form an open end 3a, and the other end is connected to the ground electrode 5 formed on the back surface via the one end surface 2a facing the one side. Have been. An excitation electrode 4 is formed on the end surface 2b of the base 2 on the extension of the open end 3a of the radiation electrode 3. A gap g is provided between the open end 3a and the edge of the excitation electrode 4.

The excitation electrode 4 extends to the back surface of the base 2 and is electrically insulated from the ground electrode 5 by the base. Then, the excitation electrode 4 and the radiation electrode 3 are electromagnetically coupled by the capacitance formed in the gap g.

As described above, in this embodiment, when mounting the surface-mounted antenna 1 on one end 11 of one main surface of the substrate 10, the open end of the radiation electrode 3 of the surface-mounted antenna 1 is mounted. The 3a side, that is, the excitation electrode 4 side is the substrate 10
Other end 12 opposite one end 11 of one main surface of
Since the surface-mount antenna 1 is mounted on the substrate 10 so as to face the direction, the excitation electromagnetic field from the excitation electrode 4 is applied to the substrate 1.
Thus, it does not go around the ground electrode 14 on the back surface of the substrate 10 via the end surface 13 on the side of the one end portion 11 of 0, thereby preventing a decrease in gain.

In this embodiment, a substrate 10 on which the surface mount antenna 1 shown in FIG.
Substrate 20 mounted on the surface actual type antenna 30 shown in 2
FIG. 4 shows the radiation pattern characteristics on the XY plane of FIG.
And FIG. The average gain of the present embodiment shown in FIG.
At B, the average gain of the conventional example shown in FIG. 5 was -10 dB. This embodiment is improved by about 5 dB.

Next, as shown in FIG. 6, the board 10 on which the surface mount antenna 1 is mounted in this embodiment is mounted on the communication device 100. This communication device 100
In this case, the functions and effects of the substrate 10 are similarly exhibited. Next, a modification of the surface mount antenna will be described. The surface-mounted antenna 1a shown in FIG. 7 extends the open end 3a of the radiation electrode 3 of the surface-mounted antenna 1 shown in FIG. 3, extends to the middle of the end surface 2b, and does not have the radiation electrode 6 and the open end 6a. ,And,
Accordingly, the excitation electrode 4 is shortened to form the excitation electrode 4a, and the gap g is formed on the end face 2b. The other parts are the same as those shown in FIG. Surface mount antenna 1a according to this variation has the same function as a surface mount antenna 1 shown in FIG. 3, particularly to form a gap g on the end face of the base body 2, a feeder electrode 4a Radiation of the coupled electromagnetic field can be limited.

[0014] surface-mounted antenna 1b shown in FIG. 8, the feeding electrode 4 a group member 2 of the surface mount antenna 1 shown in FIG. 3
The power supply electrode 4b is extended to the end of one main surface. The other parts are the same as those shown in FIG. Surface mount antenna 1b according to this modification has the same function as a surface mount antenna 1 shown in FIG. 3, particularly to form a gap g on the end portion of the main surface of the base member 2, feeding The radiation of the coupling electromagnetic field from the electrode 4b can be performed at the end of the main surface.

A surface mount antenna 1c shown in FIG. 9 is obtained by bending the radiation electrode 3 of the surface mount antenna 1b shown in FIG. The other parts are the same as those shown in FIG. The surface-mounted antenna 1c according to the present modification is shown in FIG.
Has the same function as that of the surface mount antenna 1b shown in FIG. 1, but the frequency can be reduced especially since the radiation electrode 7 is lengthened.

[0016]

According to the present invention, when a surface mount antenna is mounted from one end to the center of one main surface of a substrate, the open end side of a radiation electrode of the surface mount antenna,
That is, the surface-mount antenna is mounted on the substrate such that the excitation electrode side faces the other end facing one end of the one main surface of the substrate. The field does not go around the ground electrode on the back surface of the substrate via the end face near the substrate, and a decrease in gain can be prevented.

Also, in a communication device having a surface-mounted antenna substrate mounted as described above,
Similarly, a decrease in gain can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a method for mounting a surface-mounted antenna according to the present invention on a substrate.

FIG. 2 is a partially enlarged side view of FIG. 1;

FIG. 3 is an enlarged perspective view of the surface mount antenna shown in FIGS. 1 and 2;

FIG. 4 is a radiation pattern diagram of a mounting substrate formed according to the present invention.

FIG. 5 is a radiation pattern diagram of a mounting board formed according to a conventional example.

FIG. 6 is a perspective view of a communication device according to the present invention.

FIG. 7 is a perspective view of a modification of the surface mount antenna according to the present invention.

FIG. 8 is a perspective view of another modification of the surface mount antenna according to the present invention.

FIG. 9 is a perspective view of another modification of the surface mount antenna according to the present invention.

FIG. 10 shows mounting of a conventional surface mount antenna on a substrate.
Perspective view explaining the method

11 is a partially enlarged side view of FIG . 10;

FIG. 12 is a diagram showing a surface-mount type antenna shown in FIGS. 10 and 11;
Enlarged perspective view of tena

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface mount type antenna 2 Base 2a, 2b End surface 3, 6, 7, 8 Radiation electrode 3a, 6a, 8a Open end 4 Excitation electrode 5 Ground electrode 10 Substrate 11 End

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-127501 (JP, A) JP-A-7-235825 (JP, A) JP-A-7-221537 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H01Q 1/32 H01Q 1/38 H01Q 13/08

Claims (2)

(57) [Claims] 1. A rectangular substrate, and at least a surface of the substrate
A radiation electrode formed on the surface, and a radiation electrode formed on the back surface of the base.
Ground electrode and at least one end face of the substrate
And an excitation electrode formed continuously on the back
The radiation electrode has an open end at one end and the ground at the other end.
One end of the excitation electrode is connected to the excitation electrode.
Formed opposite to the open end of the radiation electrode with a gap
And a table in which the radiation electrode and the excitation electrode are electromagnetically coupled.
A surface mount antenna that mounts a surface mount antenna on a substrate
A method of mounting on a substrate, wherein the surface-mounted antenna
Together implement until the center from one end portion of one major surface of the substrate to the open end side of the radiation electrode of the surface mount antenna, the one end portion of the one main surface of the substrate A method of mounting a surface-mounted antenna on a substrate, wherein the surface-mounted antenna is mounted on the substrate so as to face a direction of the other end facing the substrate. 2. A communication device comprising a substrate on which a surface mount antenna is mounted by the mounting method according to claim 1.