JPH0583030A - Plane antenna - Google Patents

Abstract

(57) [Summary] [Purpose] No need to solder the power supply to the patch,
A flat antenna structure that is easy to assemble, has stable characteristics, and can be easily installed even in a narrow space. [Structure] A screw 56 is inserted from the upper side of the double-sided substrate 11 and is screwed into a metal pipe 50 having an internal thread 52 formed therein, and a flange 54 of the metal pipe is abutted and fixed to the patch 3.
The resin pipe 60 is put on the outer circumference of the metal pipe to
The crimp terminal 62 connected to the core wire 68 of the coaxial cable 66 is abutted and fixed to the metal pipe 50 by the nut 64 so that the opening provided in the top portion 34 of the conical portion 32 formed in FIG. The cable can be pulled out along the surface of the main plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna.

[0002]

2. Description of the Related Art A planar antenna of this type is expected to be small in size and good in appearance when used for mobile communication such as a car telephone. In particular, with the aim of exerting its function in complex environments such as urban areas and mountainous areas, a ring patch antenna that is sensitive to electric fields and a notch antenna that is sensitive to magnetic fields are simultaneously configured to enable power density reception. As shown in FIG. 9 and FIG. 10, which are announced at the National Conference of the Institute of Electronics, Information and Communication Autumn 1990.

That is, the double-sided board 11 is arranged at a distance from the conductive base plate 1, and the lower surface copper foil of the double-sided board 11 serves as the patch 3 as an element of the main antenna. The base plate 1 and the patch 3 are electrically connected by a short pin 4. The short pin constitutes a matching pin in the ring patch antenna which is the main antenna. A ring 5 is attached to the center of the patch 3 as a simple taper for expanding the band of the main antenna, and the feed shaft 2 to the main antenna is connected to the bottom of the ring 5.

As shown by a broken line in FIG. 10, the patch 3 has a notch 6 formed by peeling a copper foil to form a notch. This notch forms a pair with the microstrip line 7 formed of the upper surface copper foil of the double-sided substrate 11 to form a notch antenna as a sub-antenna.

[0005]

However, in such a conventional planar antenna as shown in FIG.
The conducting part of the antenna feed shaft 2 and the ring 5 or the conducting part of the ring 5 with the patch 3 was soldered, but since the patch has a large area, the heat of the solder is hard to be transmitted, and fixing for conduction is performed. Since it is difficult to manufacture and assemble, it is not easy to manufacture and assemble, and the antenna characteristics during mass production are likely to vary. Further, when the power supply cable is connected, power is supplied to the patch through the connector 9, and since the connector 9 is oriented in the direction perpendicular to the surface of the patch 3 and the main plate 1, it is suitable for use in a mobile body, particularly an automobile. In this case, it has been difficult to manage the cables in a place where the installation space is small.

Therefore, an object of the present invention is to provide a structure of a planar antenna which is easy to assemble, secures stable characteristics, and can be easily installed even in a narrow space.

[0007]

To this end, the present invention comprises a base plate, a patch provided parallel to the base plate at a predetermined interval and parallel to the base plate, and a short pin for electrically connecting the patch and the base plate. Has a cone-shaped portion whose top portion faces the patch, and the top portion is provided with an opening, and the patch and a conductive pipe covered with an insulating pipe to penetrate the opening, and the conductive pipe and a power supply cable. The crimp terminals connected to the core wires are abutted and coupled by screw tightening to form a power feeding portion to the patch.

[0008]

[Function] Since the power feeding cable can be surely connected by the simple method by tightening the screw, the soldering becomes unnecessary, and the variation in the antenna characteristics during mass production is reduced. Further, since no connector is used, the cost of parts can be reduced, and since the connector or the cable does not vertically project from the bottom surface of the main board, a large installation space is not required and the degree of freedom of arrangement is increased. In addition, since the power feeding portion has a conical shape, it has an effect of widening the bandwidth.

[0009]

1 and 2 show a planar antenna 20 according to an embodiment of the present invention, in which a conductive foil on the lower surface of a double-sided substrate 11 facing a base plate 30 is a patch 3 of a ring patch antenna. 9 shows that a microstrip line 7 is formed on the upper surface of the substrate using a conductive foil on the upper surface, and a notch antenna is formed in cooperation with the notches formed in the patch.
And that of FIG. A cone-shaped portion 32 having a top portion 34 facing the patch 3 is formed in the center portion of the main plate 30, and power is supplied to the patch 3 through a conductive pipe that penetrates the top portion 34 and is fastened to the patch with a screw. It has become. That is, the screws 56 are inserted from the upper side of the double-sided substrate 11 and screwed into the metal pipe 50 as a conductive pipe having the female screw 52 formed inside, and the flange 54 of the metal pipe is brought into contact with the patch 3 to fix the double-sided substrate 11. Insert and fix.

A resin pipe 60 as an insulating pipe is covered on the outer circumference of the metal pipe 50 to penetrate an opening provided at the top 34 of the conical portion, and a crimp terminal 62 connected to a core wire 68 of a coaxial cable 66, The nut 64 that is screwed into the screw 56 allows the metal pipe 5 from the lower side in the conical portion 32.
It is fixed by abutting on 0 and joined. The lengths of the metal pipe 50 and the screw 56 are set so that the crimp terminal 62 does not contact the inner wall of the conical portion 32. The outer shield of the coaxial cable 66 is screwed to the inner wall of the conical portion 32 using a metal band 69. The pipe-shaped short pins 40 are provided at four locations around the conical portion 32, and the patch 3
And the ground plate 30 are electrically connected to each other, and power is supplied to the microstrip line 7 through the hollow portion.

With the above construction, it is not necessary to use solder for feeding power to the patch 3, and reliable feeding cable connection can be performed by a simple method by screwing. This reduces variations in antenna characteristics during mass production,
The power feeding part can be easily assembled. Further, since the connector is not vertically projected from the lower surface of the main plate, and thus a large installation space is not required, the degree of freedom of arrangement is increased. Furthermore, by eliminating the connector, the cost of parts was reduced. In addition, since the power feeding portion has a conical shape, it has an effect of widening the bandwidth.

In the above embodiment, if the screw 56 is made of resin instead of metal, the feeding metal does not project above the patch 3 and the characteristics of the notch antenna including the microstrip line 7 on the upper surface of the double-sided substrate 11 are improved. It will have no effect.

Further, a female screw is formed on the metal pipe, and the double-sided substrate 11 is sandwiched and fixed by the metal pipe 50 and the screw 56. Instead of this, a simple through hole is provided in the metal pipe, and the screw 56 and the nut are provided. The patch 3, the metal pipe, and the crimp terminal 62 may be simultaneously tightened and fixed with 64.

Next, an example of mounting the planar antenna 20 on an automobile is shown in FIGS. Shown in the figure is a body trunk lid 70, in which a resin outer panel 71 forming an outer plate is attached to an inner panel 72 having a hat-shaped cross section, and an inner molding 73 is provided inside.
Is attached, and the planar antenna 20 is disposed in a space formed by the skeleton of the outer panel 71 and the inner panel 72.

That is, the planar antenna 20 attached to the antenna fixing base 75 is exposed from the trunk interior side in the space surrounded by the skeleton of the inner panel 72 on the back side of the resin outer panel 71, and then the inner molding 73 is placed.
The antenna fixing base 75 and the inner molding 73 are simultaneously fixed to the inner panel 72 by the inner molding fixing pin 74. Thereby, the planar antenna 20
Are installed parallel to the surface of the trunk lid 70. At this time, the coaxial cable for power feeding is pulled out through between the inner molding and the inner panel. Here, from the viewpoint of the function of the antenna, the inner panel 72 may be made of metal without any problem.

An inner panel 72 surrounding the planar antenna 20.
The skeleton of the hat-shaped cross section cooperates with the outer panel 71 to form a closed cross section and serves as an air passage 78. Further, as shown in FIGS. 5 and 6, the trunk lid 70
A trunk lid arm 80 having a closed cross section is attached to the skeleton of the inner panel located in the left and right portions of the vehicle and communicating with the air passage 78, and air communication holes 79 are provided in the contact surfaces of each other. .. Note that FIG. 5 shows a state in which the inner molding is removed for simplicity.

On the other hand, as shown in FIG. 7, the air conditioning unit 90 mounted in the vehicle typically includes an intake door 9
1, a blower fan motor 92, a heater core 93, an air mix door 94, a defroster door 95, a vent door 96, a foot door 97, and the like, and a trunk heater door 98 are provided. An air duct hose 82 extends from the trunk heater door 98, is connected to the right trunk lid arm 80, and hot air from the air conditioning unit 90 is sent to the air passage 78 of the trunk lid 70. Then, as shown by the arrow in FIG. 5, the hot air passes through the air passage 78 of the skeleton portion surrounding the planar antenna 20 and the like, and then passes through the left trunk lid arm 80 and is connected to the air duct hose 84. Discharged from.

According to the above-described mounting, the planar antenna is detachably mounted in the space between the inner panel and the outer panel of the trunk lid 70 having the resin outer panel 71, so that it is mounted on the roof portion of the vehicle body. In this case, using a resin cover only for the mounting part to transmit radio waves causes a problem of waterproofing and a problem that the color and gloss of the vehicle body surface coating change and the appearance becomes poor. The antenna can be easily attached and removed without worry, and the uniformity of the surface coating is ensured. In addition, the coaxial cable can be pulled out along the ground plane without a connector extending perpendicular to the plane of the antenna ground plane, so it is not necessary to make a large space, or it is necessary to make a hole in the vehicle body for installation. Nor.

Further, since the skeleton of the trunk lid serves as a hot air passage, the antenna characteristics can be kept stable regardless of changes in the weather. That is, FIG. 8 shows the antenna return loss characteristics when a resin plate is provided on the upper part of the ring antenna and 15 cm of snow is piled up. You can see that it is gone. The radio waves are reflected by the accumulation of snow and moisture, the characteristics of the antenna are changed, and the sensitivity is deteriorated. In such a case, the trunk heater door 98 shown in FIG. 7 is opened and the heater core 9 is opened.
The hot air generated from 3 can be guided to the air duct hose 82 by rotating the blower fan motor 92. This hot air is guided to the trunk lid arm 80 and removes snow and the like around the antenna through the air passage that surrounds the planar antenna 20, so that the antenna characteristics do not deteriorate.

[0020]

As described above, according to the inventions of claims 1 to 3, in common, it is not necessary to use solder for feeding power to the patch, and reliable feeding cable connection can be made by a simple method by screwing. It became so. As a result, it is possible to easily assemble the power feeding portion while reducing variations in antenna characteristics during mass production. Further, since the connector is not vertically projected from the lower surface of the main plate, and thus a large installation space is not required, the degree of freedom of arrangement is increased. Further, by eliminating the connector, the cost of parts can be reduced. In addition, since the power feeding portion has a conical shape, it has an effect of further widening the bandwidth.

Further, according to the second aspect of the invention, since the conductive pipe is formed with the internal thread, the conductive pipe is first fixed to the patch by cooperation with the screw penetrating the patch at the time of assembly. Has the effect of facilitating.

According to the third aspect of the present invention, since the screw is made of resin, the feeding metal does not project above the patch 3, so that the notch antenna in which the microstrip line is formed on the upper surface of the double-sided board is used. , And has the effect of not affecting the antenna characteristics.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a detailed view of part A of FIG.

FIG. 3 is a sectional view showing an example of mounting the planar antenna according to the present invention.

4 is a sectional view taken along line BB of FIG.

FIG. 5 is a perspective view of the back surface of the trunk lid.

6 is an enlarged view of a C portion of FIG.

FIG. 7 is a diagram showing an air conditioning unit.

FIG. 8 is a diagram showing changes in antenna characteristics due to snow.

FIG. 9 is a diagram showing a conventional example.

FIG. 10 is a plan view of FIG.

FIG. 11 is a diagram showing details of a D section in FIG. 9.

[Explanation of symbols]

 1, 30 Base plate 2 Feeding shaft 3 Patch 4, 40 Short pin 5 Ring 6 Notch 7 Microstrip line 9 Connector 11 Double-sided substrate 20 Planar antenna 32 Conical portion 34 Top 50 Metal pipe 52 Female screw 54 Flange 56 Screw 60 Resin pipe 62 Crimp terminal 64 Nut 66 Coaxial cable 68 Core wire 69 Metal band 70 Trunk lid 71 Outer panel 72 Inner panel 73 Inner molding 74 Pin 75 Antenna fixing base 78 Air passage 79 Air communication hole 80 Trunk lid arm 82, 84 Air duct hose 90 Air conditioning unit 91 Intake door 92 Blower fan motor 93 Heater core 94 Air mix door 95 Defroster door 96 Vent door 97 Foot door 98 Trunk heater door

Claims (3)

[Claims] 1. A base plate, a patch provided parallel to the base plate at a predetermined distance from the base plate, and a short pin for electrically connecting the patch and the base plate. The base plate has a conical shape with a top portion facing the patch. A portion is formed, an opening is provided in the top portion, the patch and a conductive pipe that covers the outer circumference and penetrates the opening, and the conductive pipe and a crimp terminal connected to the core wire of the power supply cable are formed. , A planar antenna characterized in that a power feeding portion to the patch is constituted by abutting and coupling by screw tightening. 2. A female screw is formed on the conductive pipe,
2. The patch is screwed with a screw penetrating from above to be abuttingly coupled with the patch, and the crimp terminal is abuttingly coupled with a conductive pipe by a nut screwed with the screw. Planar antenna. 3. A base plate, a double-sided substrate which is provided in parallel upward with a predetermined distance from the base plate, and which uses the lower surface conductive foil as a patch to form a microstrip line of a notch antenna with the upper surface conductive foil, the patch and the ground plate. And a conical portion with a top facing the patch is formed on the main plate, an opening is provided at the top, a female screw is formed, and an outer circumference is covered with an insulating pipe to cover the opening. The conductive pipe that penetrates is threadedly engaged with a resin screw that penetrates the double-sided board from above, abuttingly coupled to the patch, and the crimp terminal connected to the core wire of the power supply cable by the nut that is screwed with the resin screw is the conductive pipe. A planar antenna characterized in that it is abutted and coupled to a power feeding portion to the patch.