JPH06283922A - Plane antenna and radio equipment - Google Patents

Abstract

PURPOSE:To provide a plane antenna which needs no installing space and has the satisfactory characteristic by providing a through hole in an approximate area not on a radiation conductor of the antenna and forming a feeder line between the radiation conductor and the through hole to supply the power to the antenna. CONSTITUTION:A plane antenna consist of a radiation conductor 11, a dielectric 12, a ground conductor 13, and a short circuit pin 14 together with a feeding through hole 21 and a feeding pattern 22 formed nearby the conductor 11. A gap 23 is secured at the side of the conductor 13 of the hole 21 so that an electric short is prevented between the hole 21 and the conductor 13. For instance, a through hole is drilled through a dielectric substrate lined with copper on both sides. Then a pattern is shaped by an etching process. Finally a plating process is carried out together with the through hole machining. In regard of the feeding through hole 21 used for a reverse F antenna of such a constitution, a core wire 31 of a connector 2 is connected to the conductor 13 of the hole 21. Meanwhile an outer conductor 32 is connected to the conductor 13. Thus the antenna can be used for transmission or reception.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna applied to a wireless device such as a portable telephone and a wireless device having the planar antenna attached thereto.

[0002]

2. Description of the Related Art Conventionally, a microstrip antenna shown in FIG. 8 has been developed as a planar antenna. This microstrip antenna includes a radiation conductor 11 and a dielectric 1.
2. The antenna is a three-layer antenna including the ground conductor 13 and its radiation characteristics are determined mainly by the dimensions of the radiation conductor 11, the relative permittivity of the dielectric 12, and the thickness of the dielectric 12.

Electric power is supplied to this antenna by setting a power supply point on the radiation conductor 11 at a position matching the power supply system. Here, the structure of the power feeding portion of the conventional planar antenna is shown in FIGS. 9 and 10 by taking the above-mentioned microstrip antenna as an example. The example shown in FIG. 9 is a method in which the feeder line 31 is routed from the periphery of the antenna without processing the antenna, and is soldered directly onto the radiation conductor 11 with the solder 33. This method does not require drilling in the antenna, and is an effective method at the trial production stage for finding the feeding point position.

In the example shown in FIG. 10, the radiation conductors 11,
This is a method in which a hole penetrating the dielectric 12 and the ground conductor 13 is provided, a power supply line 31 is passed through the hole, and the radiation conductor 11 is soldered with solder 33. However, it is necessary to increase the diameter of the hole on the side of the ground conductor 13 to prevent short-circuiting between the power supply line 31 and the ground conductor 13. This method is used when the connector 2 is directly attached to the ground conductor 13 or the semi-rigid cable 3 is soldered.

[0005]

However, in the above-described conventional antenna, it is difficult to accurately set the feeding point position by the method of FIG. 9, for example, and variations in the feeding position during mass production cause impedance mismatch. Cause.

In the method of FIG. 10, the variation of the feeding point during mass production is smaller than that of the method of FIG. 9, but a high dielectric constant substrate is used, or an inverse F antenna, which is a type of microstrip antenna, is radiated. In an antenna where the impedance changes sharply at the edge of the element,
Variations in the positions of through holes cause impedance mismatch. In addition, both methods require soldering on the surface of the radiation conductor of the antenna. When the radome 4 is mounted on the antenna as shown in FIG. 11 and FIG. 12, the solder 33 leaves a clearance with the radome 4. This hindered the minimization of g ₁ and g ₂ .

A first object of the present invention is to provide a planar antenna which has good characteristics and does not occupy an installation space.

A second object of the present invention is to provide a wireless device which is compact and can incorporate an antenna having good characteristics.

[0009]

In the planar antenna of the present invention, as shown in FIG. 1, for example, the radiation conductor 11 of the planar antenna is fed with a through hole 21 provided in a proximity region not on the radiation conductor 11. Radiating conductor 11 and through hole 2
The power supply line 22 connecting 1 is formed by etching.

Further, in this case, the central portion of the through hole of the antenna is cut and processed together with the dielectric substrate as shown in FIG.

Further, the radio apparatus of the present invention is, for example, as shown in FIG. 6, in a radio apparatus 40 having a plane antenna for transmission or reception, power is supplied to the radiation conductor 11 of the plane antenna on the radiation conductor 11. A through hole 21 is provided in a non-existing vicinity region, a power supply line 22 connecting the radiation conductor 11 and the through hole 21 is formed by etching, and the central portion of the through hole is cut and processed together with the dielectric substrate.

[0012]

According to the planar antenna of the present invention, since the feeding point is set by etching, the variation of the feeding point position during mass production can be made smaller than that of mechanical processing, and at the same time the antenna radiation is performed. It is possible to narrow the gap between the radome and the antenna radiation conductor surface without the need for soldering the conductor surface.

Further, in this case, the workability can be improved by cutting the central portion of the through hole together with the dielectric substrate so that the feeder line can be soldered to the cross section of the through hole.

Further, according to the wireless device of the present invention, it is possible to incorporate a planar antenna having good characteristics in which there is no variation in the position of the feeding point, which leads to improvement in the performance of the wireless device, and at the same time, a feeding line is provided on the surface of the antenna. The antenna can be housed in a narrow space inside the wireless device without any protrusion due to the connection.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
Will be described with reference to. 1 to 3, parts corresponding to those of FIGS. 8 to 12 shown as a conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

1 and 2 are views showing the configuration of the planar antenna of this example, which is an inverted F antenna which is a modification of the microstrip antenna. That is, it has a structure in which a conductor pin 14 (or a through hole or the like) is short-circuited between the edge of the radiation conductor 11 and the ground conductor 13 which form the microstrip antenna. It is an antenna that can be downsized to about 1/4 in the side length and about 1/16 in the area of the radiation conductor compared to the antenna.

In this example, as shown in FIG. 1, the radiation conductor 11, the dielectric 12, the ground conductor 13 and the short-circuit pin 14 are provided, and the power feeding through hole 21 and the power feeding pattern 22 are provided in the vicinity of the radiation conductor 11. Let it form. However, as shown in the cross section of the through hole 21 in FIG. 2, the through hole 21 is provided on the ground conductor 13 side of the power feeding through hole 21.
And the ground conductor 13 do not electrically short-circuit the gap 23
Is provided.

In this case, for example, a hole for a through hole is formed in a dielectric substrate with double-sided copper clad, the pattern is shaped by using an etching technique, and finally a plating process and a through hole process are performed to obtain such a structure. It can be shaped.

Then, as shown in FIG. 2, the true wire 31 of the connector 2 (or the semi-rigid cable 3) is connected to the ground conductor 13 side of the feed-through hole 21 of the inverted F antenna configured as described above, and the outside By connecting the conductor 32 to the ground conductor 13, it operates as an antenna for transmission or reception.

Of course, the surface of the antenna may be covered with the radome 4 as shown in the cross section of FIG. Further, as shown in FIG. 3, it is conceivable that the power supply through hole 21 and the true wire 31 of the semi-rigid cable 3 are connected by soldering inside the through hole 21 with solder 34. With this configuration, solder or the like does not project on the surface of the radiation conductor 11, and the clearance g ₀ with the radome 4 can be narrowed,
The antenna can be made compact.

Next, a second embodiment of the present invention will be described with reference to FIGS. 4 to 6, parts corresponding to those of FIGS. 8 to 12 shown as the conventional example and FIGS. 1 to 3 shown as the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. .

FIGS. 4 and 5 are views showing the structure of the planar antenna of this example. In the case of this example, the inverted F antenna formed in the same manner as in the above-mentioned first embodiment is cut. It is the one. In this case, the cut surface passes through the center of the power supply through hole 21. That is, here, the inverted F antenna formed as shown in FIG. 1 is cut along the line I-I to have a shape as shown in FIG. By doing so, as shown in FIG. 4, the feeding through hole 21 is exposed in the dielectric 12 on the end face of the antenna. In this state, as shown in FIG. 5, the true wire 31 of the connector 2 (or the semi-rigid cable 3) is soldered with the solder 35 in the vicinity of the central portion of the exposed power supply through hole 21, so that the soldering point is Since it is exposed to the outside, it is possible to easily attach the feeding line such as soldering. Note that FIG. 5 is a view showing the end portion of the antenna, in which only the connector 2 is shown in cross section. The other parts are configured similarly to the planar antenna of the first embodiment described above.

FIG. 6 shows an example in which the planar antenna thus constructed is arranged in a radio device. In FIG. 6, reference numeral 40 denotes an entire radio device, and the radio device 40 is configured as a mobile phone having a reception section 41 and a transmission section 42 on the front side, and by disposing this planar antenna at a predetermined position on the upper side, The antenna does not protrude from the device 40 and the radio 4
It is efficiently stored in 0. In the case of the second embodiment as well, it goes without saying that the surface of the antenna may be covered with the radome 4.

Next, a third embodiment of the present invention will be described with reference to FIG. In FIG. 7, parts corresponding to FIGS. 8 to 12 shown as a conventional example and FIGS. 1 to 6 shown as the first and second embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted. .

In this example, as shown in a sectional view in FIG. 7, the feed through hole 21 of the planar antenna shown in the first embodiment is connected to the through hole 2 from the ground conductor 13 side.
A hole 24 having a diameter larger than 1 is drilled to the vicinity of the central portion, and the power feed through hole 21 and the true wire 31 of the semi-rigid cable 3 are soldered with the solder 36 in the hole 24. This is to avoid a short circuit of 13. The other parts are configured similarly to the planar antenna of the first embodiment described above.

With this configuration, even when the antenna is installed in, for example, a metal housing, it is not necessary to perform additional work such as making a relief on the metal housing side to avoid a short circuit. In the case of the example shown in FIG.
Similar to the case of the second embodiment, it may be cut so as to pass through the center of the power supply through hole 21. By doing so, workability such as soldering can be improved as in the case of the second embodiment. Also, this third
In the case of the above embodiment as well, it goes without saying that the surface of the antenna may be covered with the radome 4.

[0027]

According to the planar antenna of the present invention, the following effects can be obtained. 1. The positional accuracy of the feeding point is improved, and the occurrence of impedance mismatch can be suppressed. 2. Since the feeding point is set by etching, it is possible to suppress variations during mass production. 3. Since the feeding point is set by etching, the connection portion to the radiation conductor can be made extremely thin, which enables more accurate control of the feeding point position. 4. It is not necessary to solder the surface of the radiation conductor, and the clearance with the radome can be minimized.

Further, by cutting so as to pass through the power supply through hole, it becomes possible to solder the power supply line to the side surface of the antenna, thus improving workability.

Further, according to the wireless device having the planar antenna built in as described above, since the above-described effects can be obtained, the antenna which has a good characteristic and can be formed in a small size is built in, and the transmission / reception performance of the wireless device is improved. It can be improved and leads to miniaturization of the wireless device.

[Brief description of drawings]

FIG. 1 is a perspective view showing a planar antenna according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II of FIG.

FIG. 3 is a cross-sectional view showing a state in which a radome is attached to the planar antenna of the first embodiment.

FIG. 4 is a perspective view showing a planar antenna according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a feeder mounting portion of a planar antenna according to a second embodiment.

FIG. 6 is a perspective view showing a state in which the planar antenna of the second embodiment is attached to a wireless device.

FIG. 7 is a sectional view showing a planar antenna according to a third embodiment of the present invention.

FIG. 8 is a perspective view showing an example of a conventional planar antenna.

FIG. 9 is a cross-sectional view showing an example of a feeder attachment portion of a conventional planar antenna.

FIG. 10 is a cross-sectional view showing another example of a feeder attachment portion of a conventional planar antenna.

FIG. 11 is a cross-sectional view showing an example of a conventional flat antenna mounted on a radome.

FIG. 12 is a cross-sectional view showing another example of a conventional planar antenna mounted on a radome.

[Explanation of symbols]

 2 connector 3 semi-rigid cable 4 radome 11 radiation conductor 12 dielectric 13 ground conductor 14 short-circuit pin 21 power feed through hole 22 power feed pattern 23 gap between through hole and ground conductor 24 hole 31 power feed line (true line) 32 outer conductor 34, 35, 36 Solder 40 Radio

Claims (3)

[Claims] 1. A planar antenna for feeding power to a radiation conductor of a planar antenna, wherein a through hole is provided in a region not on the radiation conductor and a feeding line connecting the radiation conductor and the through hole is formed by etching. 2. The planar antenna according to claim 1, wherein the central portion of the through hole is cut and processed together with the dielectric substrate. 3. A radio device having a plane antenna for transmission or reception, wherein the radiation conductor of the plane antenna is fed with a through hole provided in a region not on the radiation conductor and connecting the radiation conductor with the through hole. A wireless device in which an electric wire is formed by etching and the central portion of the through hole is cut and processed together with a dielectric substrate.