JP3040916B2 - Antenna for small radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna for a portable radio, and more particularly to an antenna for a small radio receiver.

[0002]

2. Description of the Related Art Conventionally, loop antennas are often used as antennas for small radio receivers such as pagers, and high sensitivity characteristics have been obtained. FIG. 1 is a partial perspective view of a receiver equipped with a conventional antenna. In the figure, 1 is a circuit board of a receiver, 2 is a loop antenna, and 3 is a battery.
In the conventional loop antenna 2, half of the loop antenna 2 is provided on the upper and lower surfaces of the circuit board 1 so that the circuit board 1
Are mounted such that the loop surface is at right angles to the. The assembly work of the loop antenna 2 on the substrate 1 is performed in a process after the circuit components are mounted on the substrate. Printed wiring conductors are provided on both sides of the circuit board 1, and circuit components of the receiver are mounted on both front and back sides, but are not shown.
The antenna element 2-1 on the upper part of the circuit board 1 and the antenna element 2-2 on the lower part are integrally formed.
FIGS. 1B and 1C are partial perspective views showing details of a structure for attaching the antenna 2 to the circuit board 1. FIG. Parts A and C
Each of the lands of the wiring conductor having a slight gap from the top and bottom of the circuit board 1 is soldered to an excitation portion (feed point). Part B is soldered to the printed conductor so as to sandwich the edge of the circuit board 1 as shown in FIG.

[0003]

This antenna mounting operation is difficult to mechanize and is performed almost manually, so that it has been extremely difficult to reduce the assembly cost. It is necessary to reduce the number of assembling steps and to mechanize the assembling work in order to supply radio equipment with excellent economy, but this is very difficult with the conventional loop antenna.

[0004] An object of the present invention is to solve the above-mentioned problem, and it is an object of the present invention to provide a loop antenna with good assemblability without impairing conventional electric characteristics.

[0005]

An antenna for a small radio receiver according to the present invention is formed on a circuit board by printed wiring conductors.
Printed antenna element portion, and the printed antenna element portion
To form a loop antenna, one
One end is fixed to one end of the printed antenna element and the other end is the mark.
On the land at a predetermined distance from the other end of the antenna element
With the fixed conductive member half-loop antenna element
An antenna for small radio receiver configured I, before
The printed antenna element is formed in a U-shape on the circuit board.
Formed and the mounting position of the antenna element portion is shifted
Features configured to reduce the effects of circuit components
It is assumed that.

[0006]

[0007]

[0008]

FIG. 2 is a perspective view showing a first embodiment of the present invention. As in the case of FIG. 1, illustration of the printed wiring conductors of the circuit board 1 and other circuit components is omitted. In the drawing, reference numeral 4 denotes a half-loop antenna element portion which is made of a metal plate having good conductivity or a plate plated with metal having good conductivity such as silver or gold, and forms a part of a loop antenna. Reference numeral 5 denotes a printed antenna element formed in the same step as the wiring conductor forming step for mounting other circuit components on the circuit board 1.
One A end of the half-loop antenna element portion 4 is connected to the circuit board 1
And the other B end is placed on the end of the printed antenna element portion 5 and fixed by reflow soldering in the same manner as other electric components. A loop antenna is formed by the antenna element section 4 and the printed antenna element section 5. The AC end is the excitation end (power supply end). A receiver input circuit such as a tuning circuit and a matching circuit may be formed in a part of the printed antenna element unit 5, and the printed antenna element unit 5 may be subjected to a resist process.

FIG. 3 is a perspective view for explaining a second embodiment of the present invention. The printed antenna element 6 is formed in a U-shape, and the mounting position of the antenna element 4 is shifted. This is effective in improving the radiation directivity of an antenna that is distorted by the influence of circuit components.

FIG. 4 is a perspective view for explaining a third embodiment of the present invention. The printed antenna element 7 is formed on the surface opposite to the mounting surface of the half-loop antenna element 4, and the effective area of the loop antenna is reduced. This is an example in which the radiation efficiency is increased. Reference numeral 8 denotes a through hole for electrically connecting the printed antenna element 7 and the half-loop antenna element 4.

[0011]

By implementing the present invention, the following effects can be obtained. (1) By using a conductor formed by printing a part of the loop antenna on a circuit board, mechanization of mounting the loop antenna is facilitated and the assembly cost can be significantly reduced. (2) By shifting the positions of the printed antenna element and the half-loop antenna element, the radiation characteristics of the antenna can be improved. (3) By forming the printed antenna element on the surface opposite to the mounting surface of the half-loop antenna element, the loop area can be increased and the radiation efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a conventional antenna configuration example.

FIG. 2 is a perspective view illustrating a first embodiment of the present invention.

FIG. 3 is a perspective view illustrating a second embodiment of the present invention.

FIG. 4 is a perspective view illustrating a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Circuit board 2 Loop antenna 3 Battery 4 Half loop antenna element part 5, 6, 7 Printed antenna element part 8 Through hole

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoshikuni Makino 3-14-20 Higashinakano, Nakano-ku, Tokyo International Electric Company (72) Inventor Hiroshi Noguchi 3-14-20 Higashinakano, Nakano-ku, Tokyo Kokusai Denki Co., Ltd. (56) References JP-A 61-61212 (JP, U) JP-A 61-29508 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) H01Q 1/24

Claims (1)

(57) [Claims] 1. Formed on a circuit board by printed wiring conductors
Printed antenna element portion, and the printed antenna element portion
To form a loop antenna, one
One end is fixed to one end of the printed antenna element and the other end is the mark.
On the land at a predetermined distance from the other end of the antenna element
With the fixed conductive member half-loop antenna element
In the antenna for a small radio receiver configured as described above, the printed antenna element portion is formed in a U-shape on the circuit board.
And the mounting position of the antenna element portion is shifted.
To reduce the effects of circuit components.
An antenna for a small radio receiver.