JP2903820B2 - Planar antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna, and more particularly to a planar antenna characterized by the configuration of a matching pin.

[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 an automobile telephone. In particular, a ring patch antenna that responds to an electric field and a notch antenna that responds to a magnetic field are simultaneously configured to enable power density reception, with the aim of exhibiting functions in complex environments such as urban areas and mountainous areas. As shown in FIG. 4 which was announced at the 1990 Fall National Convention of the Institute of Electronics, Information and Communication Engineers.

That is, a double-sided board 11 is arranged at a distance from the ground plane 1 of a conductor, and a copper foil on the lower surface of the double-sided board 11 is used as a patch 3 as an element of a main antenna. The ground plate 1 and the patch 3 are electrically connected by the short pin 4. The short pins 4 constitute matching pins in a ring patch antenna serving as a 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 a feed shaft 2 from a connector attached to the base plate is connected to the bottom of the ring 5. The short pins 4 are provided at four locations around the central power supply shaft 2.

[0004] A notch (not shown) is formed in the patch 3 to form a notch. This notch is a microstrip line 7 formed of copper foil on the upper surface of the double-sided substrate 11.
And a notch antenna as a sub-antenna. The power supply to the sub-antenna is performed by the power supply shaft 8 of the connector 10 which also serves to maintain the interval between the ground plate and the patch. In the figure,
Reference numeral 9 denotes a power supply connector to the main antenna, and reference numeral 31 denotes a power supply cable to the sub-antenna connected to the connector 10.

[0005] The short pin 4 is embodied by using a connector 10.
Numeral 0 has a flange 12 connected to the connection portion with the power supply cable, and a resin outer cylinder 14 extending from the flange, and the power supply shaft 8 extends as a core line at the center of the outer cylinder. Connector 10
Has the flange 12 fixed to the base plate 1 and the outer cylinder 14 is erected toward the patch 3, and the tip of the outer cylinder 14 is in contact with the double-sided board. Only the power supply shaft 8 penetrates the double-sided substrate 11 and is soldered to the microstrip line 7 on the upper surface of the substrate.
On the other hand, since the outer cylinder 14 of the connector 10 is made of a non-conductive resin, a conductive tape 16 is wrapped around the outer cylinder, and one end of the conductive tape is attached to the patch 3 of the double-sided board and the other end is attached to the base plate 1. Are connected to each other with a silver paste to perform a conduction function as the short pin 4.

[0006]

However, in the above planar antenna, the mechanical assembly strength between the base plate 1 and the double-sided substrate 11 is maintained by using the power supply connector 10 for the sub-antenna. Silver paste connection to the patch 3 and the base plate 1 of the conductive tape 16 wound around the cylinder,
Since it is only soldered to the power supply shaft, when it is mounted on a mobile object such as an automobile, which is originally intended, the conductive tape 16 is loosened due to vibration or the silver paste portion is peeled off, resulting in poor conduction and poor structure. There is a risk of the occurrence of rattling.

[0007] Furthermore, the use of the connector itself is extremely expensive at present, and there is a problem that the cost is too high because five connectors including the central connector are used.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a highly reliable planar antenna which is robust in structure, does not cause poor conduction, can be easily assembled, and can be manufactured at a low cost. I do.

[0009]

SUMMARY OF THE INVENTION For this reason, the present invention provides a patch provided with a notch provided above and spaced apart from a ground plate of an electric conductor, in which power is supplied at the center of the patch and the short pin is connected to the ground plate. The sub-antenna element is a microstrip line provided across the notch in an insulated state on the patch, and the short pin has a flange at one end. Abutting the lower surface of the base plate, a metal pipe penetrating a hole formed in the base plate and the other end is soldered to the patch, a power supply cable is introduced from the flange side to the metal pipe,
A core wire of the power supply cable penetrates the patch, is connected to the microstrip line, is supplied to the sub-antenna, and a band fixing the power supply cable is screwed to the lower surface of the main plate together with the flange. did.

[0010]

[Function] Since the short pin is soldered to the patch as a rigid metal pipe and the base plate is fixed by connecting the flange of the metal pipe with a screw, the patch and the base plate are electrically connected and mechanically. They are rigidly connected to form a robust and rigid structure as a whole. Also,
A band for fixing a power supply cable to the sub-antenna to be introduced into the metal pipe is screwed to the ground plate at the same time as the flange, so that the number of parts is small and the structure is simplified.

In addition, it is not necessary to use an expensive connector for a large number of short pins, and it is sufficient to lead the power supply cable into the metal pipe as it is and to penetrate its core wire to the upper surface side of the patch. Created.

[0012]

FIG. 1 shows an embodiment of the present invention. Reference numeral 101 denotes a conductive ground plane, and 111 denotes a double-sided board opposed to the ground plane 101 with a space therebetween. A copper foil as a lower conductive foil of the double-sided board 111 is used as a patch 103 as an element of the main antenna. The ground plate 101 and the patch 103 are electrically connected by the short pin 104. The short pins 104 are provided at four positions and constitute matching pins in a ring patch antenna which is a main antenna. A ring 5 is attached to the center of the patch 103 as a simple taper for expanding the band of the main antenna, and a feed shaft 2 from a connector 9 attached to the main plate 101 is connected to the bottom of the ring 5.

As shown by a broken line in FIG. 2, the patch 103 is formed by peeling a copper foil and forming notches 106 in four directions to form notches. A notch antenna as a sub-antenna is constituted by a pair of a notch and a microstrip line 107 formed of copper foil on the upper surface of the double-sided board 111 and arranged so as to cross the notch 106.

As shown in FIG. 3, the short pin 104 is formed of a metal pipe 120 having a flange 122, is inserted into a hole provided in the main plate 101 from the lower surface of the main plate, and the tip of the short pin 104 contacts the patch 103. , Flange 1
22 contacts the lower surface of the main plate 101. Metal pipe 120
The coaxial cable 130 is inserted into the metal pipe 120 through a hole 124 formed in the metal pipe 120 as a power supply cable to the sub-antenna through a flange opening at the lower end.
20 and the shield jacket 134 of the coaxial cable 130 are joined by soldering 140.

The coaxial cable 130 is bent at the opening end of the metal pipe in the direction along the main plate 101, and its shield jacket 134 is fixed to the main plate 101 by the metal band 136. At this time, the metal band 136 is superimposed on the flange 122 of the metal pipe, and is fastened together with the flange 122 to the main plate 101 together with the screw 138. The core wire 132 of the coaxial cable 130 passes through the through hole 114 provided concentrically with the metal pipe 120 on the double-sided board 111,
It is soldered 142 to the microstrip line 107 on the upper surface of the double-sided board. The tip of the metal pipe 120 and the patch 103 are soldered 144 at a contact portion.

Thus, in the short pin portion made of the metal pipe 120, the microstrip line 107 of the notch antenna is fed with the core wire 132 of the coaxial cable, and the shield jacket 134 of the coaxial cable passes through the metal band 136 and the hole. Conduction is made to ground plate 101 through metal pipe 120 soldered at 124 parts.

According to the above configuration, since the coaxial cable 130 for feeding power to the sub-antenna is guided directly into the metal pipe 120, it is not necessary to use an expensive connector, and it is possible to manufacture at low cost. Also, since the patch 103 and the base plate 101 are connected by the metal pipe 120, there is no fear of loosening or peeling as in the case of using a conductive tape, and the metal pipe 120 and the shield jacket 134 of the coaxial cable are soldered. There is no burden on the core wire 132, the durability of the antenna is increased, and there is no fear of poor conduction.

In the illustrated embodiment, the patch and the microstrip line are described as being formed of copper foil on a double-sided board. However, the present invention is not limited to this. The mounted microstrip line may be provided on the patch.

[0019]

As described above, according to the present invention, the short pin is soldered to the patch as a metal pipe having a flange, and the flange is screwed to the base plate together with the band for fixing the coaxial cable. The base plate is mechanically and strongly connected together with the electrical conduction, so that a robust and rigid structure as a whole is obtained. In addition,
It is not necessary to use an expensive connector for a large number of short pins, and it is sufficient to lead the power supply cable into the metal pipe as it is, penetrate its core wire to the upper surface side of the patch, and screw the metal pipe and band together. Created at cost. Suitable for mass production due to reliability and low cost.

[Brief description of the drawings]

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

FIG. 2 is a top view of the embodiment.

FIG. 3 is a diagram showing details of a portion A in FIG. 1;

FIG. 4 is a side view showing a conventional example.

FIG. 5 is a diagram showing details of a portion B in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground plate 2, 8 Feeding axis 3 Patch 4 Short pin 5 Ring 7 Microstrip line 9, 10 Connector 11 Double-sided board 12 Flange 14 Outer cylinder 16 Conductive tape 31 Power supply cable 101 Base plate 103 Patch 104 Short pin 106 Notch 107 Microstrip line 111 double-sided board 114 through hole 120 metal pipe 122 flange 124 hole 130 coaxial cable 132 core wire 134 shield jacket 136 metal band 138 screw 140, 142, 144 soldering

Claims (1)

(57) [Claims] 1. A patch provided with a notch and disposed above and spaced apart from a ground plane of a conductor is supplied with power at the center thereof and is electrically connected to the ground plane via short pins to form an element of a main antenna. A microstrip line provided across the notch in an insulated state on the patch as an element of the sub-antenna, the short pin has a flange at one end and abuts the flange against the lower surface of the base plate; The other end is formed of a metal pipe soldered to the patch through the hole formed in the base plate, a power supply cable is introduced into the metal pipe from the flange side, and a core wire of the power supply cable passes through the patch. Is connected to the microstrip line to be fed to the sub-antenna, and a band for fixing the feed cable is connected to the flange. A planar antenna, wherein the planar antenna is screwed to the lower surface of the main plate by fastening together.