JP2000151259A - Antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna which is small-sized and has high gain and high reliability. SOLUTION: In a planar antenna which respectively provides both principal planes of a substrate 1 with a radiation electrode 2 and an earth electrode and has a structure provided with a power feeding pin 4a which is electrically connected to the radiation electrode 2 and does not come into contact with the earth electrode, it is possible to efficiently and stably offer an antenna that is small-sized and has high gain and high reliability by optimally designing substrate material for the antenna and various conditions for electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna used for a communication system such as an antenna device for receiving a radio wave from an artificial satellite.

[0002]

2. Description of the Related Art In recent years, for signal reception from a satellite such as a GPS (Global Positioning System), use of a microstrip antenna has been considered, and a planar antenna has been used as one type of the antenna.

As a material for an antenna substrate, a relative dielectric constant of 6
The following resin substrates and ceramic substrates having a relative dielectric constant of 20 or less have been used.

[0004]

However, according to the conventional antenna substrate material, the conductor loss of the silver electrode is large due to the roughness of the substrate surface, and the dielectric loss of the substrate material is low because the density after the substrate sintering is low. Because of the large
It has been difficult to provide an antenna that is small and has a high gain.

[0005] Also, as a GPS application, a car navigation system and a marine GPS were conventionally used, but in the future, the GPS will be applied to mobile terminals such as mobile phones and personal computers.
It is conceivable to have an S function, and miniaturization of the antenna element is desired.

According to the present invention, various conditions (relative permittivity, surface roughness, sintered density, substrate material, substrate shape, electrode material, electrode thickness, etc.) of an antenna substrate body and electrodes are appropriately designed. It is an object of the present invention to provide a small, high-gain antenna efficiently and stably.

[0007]

According to the present invention, there is provided a substrate, a radiation electrode provided on one main surface of the substrate, an earth electrode provided on the other main surface of the substrate, and a radiation electrode. It has a configuration in which the power supply means is electrically connected and provided in a non-contact manner with the ground electrode.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is a substrate, a radiation electrode provided on one main surface of the substrate, a ground electrode provided on the other main surface of the substrate, and a radiation electrode. By providing a power supply unit which is joined and is provided in non-contact with the ground electrode, it becomes possible to transmit and receive radio waves.

According to a second aspect of the present invention, in the first aspect, by setting the relative dielectric constant εr of the substrate to 6 or more and 150 or less, it is possible to promote the miniaturization of the antenna and widen the resonance frequency band. Further, variation in characteristics can be suppressed.

According to a third aspect of the present invention, the material of the substrate according to the second aspect is a forsterite-based ceramic, an alumina-based ceramic, a calcium titanate-based ceramic, a magnesium titanate-based ceramic, a zirconia-tin-tin.
Titanium-based ceramics, barium titanate-based ceramics,
By using one material system or a plurality of material systems such as lead-calcium-zirconia ceramic, lead-calcium-iron-niobium ceramic, lead-calcium-magnesium-niobium ceramic, the sinterability is improved. For the purpose of optimizing the temperature characteristics, an additive such as bismuth, manganese, samarium, niobium, lanthanum, praseo, or neodymium can be added to appropriately select the relative dielectric constant of the substrate.

According to a fourth aspect of the present invention, in the first to third aspects, the surface roughness of the substrate is set to 10 μm or less, whereby a decrease in the Q value can be prevented, and the gain of the antenna can be improved. it can.

According to a fifth aspect of the present invention, in the first to fourth aspects, the substrate is made of ceramic and the sintering density is 92% or more, so that the mechanical strength can be improved and the workability and the like can be improved. In addition, stable characteristics can be obtained, and a decrease in Q value and a variation in relative dielectric constant can be prevented.

According to a sixth aspect of the present invention, according to the first to fifth aspects, by performing at least one of chamfering and tapering on the corner of the substrate, a large chip of the corner of the plate can be prevented. Thus, the characteristics of the antenna are largely changed, and no problem occurs.

According to a seventh aspect of the present invention, in the sixth aspect, the C-chamfering is adopted as the chamfering, and the R of the C-chamfering is set to 0.1 mm or more, so that the antenna can be produced reliably and with high productivity. can do.

According to an eighth aspect of the present invention, in the first to fifth aspects, a power supply pin is used as the power supply means, a through hole is provided in the substrate, the power supply pin is inserted into the through hole, and the power supply pin and the radiation pin are radiated. The productivity can be improved by joining the electrodes and making the power supply pin and the ground electrode non-contact.

According to a ninth aspect of the present invention, there is provided the low noise amplifier according to any one of the first to eighth aspects, further comprising an antenna, a substrate forming a low noise amplifier circuit on a back surface side while holding the antenna in contact with a ground electrode of the antenna. Power supply to the amplifier board, by having a configuration provided with a coaxial cable for transmission and reception of input and output signals, it is possible to obtain the transmission and reception characteristics of the efficient holding the antenna stably,
Radio waves transmitted and received by the antenna are efficiently amplified, and signals can be reliably exchanged with the signal processing circuit.

According to a tenth aspect of the present invention, in the first to eighth aspects, the antenna, a flat plate for holding the antenna in contact with a ground electrode of the antenna, and a low-noise amplifier substrate on the other back side of the flat plate. By joining and providing a coaxial cable for supplying power to the low-noise amplifier board and transmitting and receiving input / output signals, the antenna can be stably held and efficient transmission / reception characteristics can be obtained. Radio waves transmitted and received can be efficiently amplified, and signals can be reliably exchanged with the signal processing circuit.

According to an eleventh aspect of the present invention, in the ninth aspect, a projection for positioning the antenna according to the first to eighth aspects is provided on one surface of the flat plate, and the other surface on the flat plate is provided. An antenna can be produced with high productivity by providing a positioning projection for fixing the low-noise amplifier board on the surface of the antenna.

According to a twelfth aspect of the present invention, in the tenth aspect, when the antenna according to any one of the first to eighth aspects is fixed on one surface of the flat plate, and the low-noise amplifier substrate is mounted on the other surface of the flat plate. An antenna can be produced with high productivity by using a double-sided tape or an organic adhesive when fixing the antenna.

According to a thirteenth aspect of the present invention, in the tenth aspect, a low-noise amplifier substrate is directly provided on a flat plate.
An opening is provided so as to be fixed to the antenna according to claim 9, and a projection for positioning when fixing the antenna according to any of claims 1 to 9 is provided on one surface of the flat plate, and the flat plate and the flat plate are provided. The antenna can be produced with high productivity by using a double-sided tape or an organic adhesive when fixing the antenna described in any one of Items 9 to 9.

According to a fourteenth aspect of the present invention, the low-noise amplifier is covered with a box-shaped shield case made of a good conductor such as a metal to prevent a malfunction caused by receiving the noise generated from the low-noise amplifier with the antenna. it can. Alternatively, it is possible to prevent a malfunction caused by the low-noise amplifier receiving noise due to radio waves flying from the above-described antenna or the like.

Hereinafter, embodiments of the present invention will be described. 1, 2, and 3 are a front perspective view, a rear perspective view, and a cross-sectional view, respectively, showing an antenna according to an embodiment of the present invention.

1, 2 and 3, reference numeral 1 denotes a substrate, and the substrate 1 is made of a dielectric material. The relative permittivity εr of the substrate 1 is preferably 6 or more and 150 or less. Relative permittivity εr
Is smaller than 6, the substrate 1 becomes too large to reduce the size of the antenna. If the relative dielectric constant εr is greater than 150, the reduction in size can be promoted, but the resonance frequency band becomes too narrow. The resonance frequency band is deviated due to a slight difference in composition, occurrence of chipping and the like, and a change in the environment around the antenna, so that a predetermined characteristic cannot be obtained, and a characteristic variation is increased.

The specific constituent materials of the substrate 1 are resins,
Examples include liquid crystal polymers and ceramics. Among these constituent materials, it is preferable to use ceramics in consideration of good weather resistance, high mechanical strength, and low cost. When ceramic is used as a constituent material of the substrate, the sintering density is 9
It is preferably at least 2% (more preferably at least 95%). If the sintering density is 92% or less, the dielectric loss may increase and the variation in the relative permittivity εr may increase, causing a problem.

The surface roughness of the substrate 1 is preferably 10 μm or less (especially preferably 7 μm or less, more preferably 5 μm or less) in order to form an electrode described later with good quality. When the surface roughness is 10 μm or more, the conductor loss increases, and the antenna gain decreases.

When the substrate 1 is made of ceramic, it is necessary to appropriately select a material according to the relative dielectric constant. Specifically, when the relative dielectric constant is 10 or less, forsterite-based ceramics, alumina-based ceramics, and the like are used. When the relative dielectric constant is 10 to 30, examples thereof include a calcium titanate-based ceramic and a magnesium titanate-based ceramic. When the relative dielectric constant is 30 to 60, a zirconia-tin-titanium-based material or the like has a relative dielectric constant of 6
In the case of 0 to 150, barium titanate-based ceramic, lead-calcium-zirconia-based ceramic, lead-calcium-iron-niobium-based ceramic, lead-calcium-magnesium-niobium-based ceramic and the like can be mentioned.

In order to obtain a predetermined relative permittivity within the above range of the relative permittivity, these materials are composed of a single material or a plurality of material systems, and are used for improving sinterability, optimizing temperature characteristics, and the like. In some cases, additives such as samarium, bismuth, manganese, niobium, lanthanum, praseo, and neodymium may be added.

Particularly, by using a material having an εr of 10 or less, the antenna gain and the frequency bandwidth can be increased. It can be.

Further, by using a material having an εr of 10 to 30, the size of the substrate 1 can be reduced to about half as compared with a material having a εr of 10 or less. Can be downsized.

Further, by using a material having an εr of 30 to 60, the size of the substrate 1 can be reduced to about half of that of a material having an εr of 30 or less. Further miniaturization can be realized.

By using a material having an εr of 60 to 90, the size of the substrate 1 can be reduced by about 20% compared to a material having a εr of 60 or less.

Further, by using a material having an εr of 90 to 120, the size of the substrate 1 can be reduced by about 25% as compared with a material having a εr of 90 or less.

Also, by using a material having an εr of 120 to 150, the size of the substrate 1 can be reduced by about 25% as compared with a material having a εr of 120 or less.

Further, since the thickness of the substrate 1 can be reduced to 5 mm or less using any material, the size and thickness of the substrate 1 can be reduced. A product with a built-in antenna that is easy to use and has no projection or the like can be obtained.

Next, the shape of the substrate 1 is a square plate as shown in FIGS. 1, 2 and 3, or an elliptical plate or a polygonal plate (the cross section is triangular, square, pentagon...). It can be.

In this embodiment, the characteristics can be made uniform or the characteristics can be stabilized by making the thickness of the substrate 1 uniform (the thickness of the center portion and the thickness of the end portion are substantially the same). Board 1 depending on the use situation, the type of machine used, etc.
May be varied between predetermined portions. That is, for example, a plurality of concave portions can be formed in the substrate 1, or the thickness of one end of the substrate 1 can be made thicker or thinner than the thickness of the opposite end.

Further, the corner 1c of the substrate 1 is chamfered, tapered, stepped, and the like, so that the corner 1c of the substrate 1 can be prevented from being greatly chipped or changing its characteristics.

Therefore, as described above, if the corner 1c is previously subjected to chamfering, taper processing, step processing, or the like, the transmission or reception characteristics may be largely chipped in the corner 1c of the substrate 1 in the middle. Will hardly change.

At this time, it is preferable to perform C-chamfering in consideration of productivity and the ability to perform reliable corner processing.
At this time, the radius of the C chamfer is set to 0.1 mm or more (preferably 0.2 mm or more), so that even if a slight impact or the like is applied to the substrate 1, the corner 1 c of the substrate 1 is hardly chipped. However, even if a large shock or the like is applied so that the substrate 1 is chipped, only slight chipping occurs, and no significant change in transmission or reception characteristics occurs. The chamfering and tapering of the substrate 1
Whatever material the substrate 1 is made of, it is necessary. However, it is particularly effective when a ceramic which is relatively easily chipped as described above is used. Further, as another embodiment, an organic resin or the like for preventing chipping is provided on the corner 1c of the substrate 1 without performing the C-chamfering or tapering on the corner 1c of the substrate 1, thereby providing the corner 1c. Large chipping of 1c can be prevented.

In order to more surely improve the productivity, step machining is effective. Providing a stepped step at one or both of the corners 1c between the main surfaces 1a and 1b of the substrate 1 and the side surface of the substrate 1 is effective in preventing chipping at the corners of the substrate, and increases the burden on the molding die. Since it is difficult to improve the durability of the mold, the strength of the molded body is improved, and the sinterability is improved, the productivity can be improved. When performing the step processing, a more remarkable effect can be obtained by setting the following conditions.

0.1 mm ≦ A ≦ 1.5 mm 0.1 mm ≦ B ≦ 1.5 mm where A represents the width of the step with the main surface of the substrate, and B represents the width of the step with the side surface of the substrate.

When the width of the substrate 1 is L1 (cm), the length is L2 (cm), and the thickness is L3 (cm), the antenna satisfies the following conditions, so that the antenna is built in the transmitting / receiving device or the circuit is The antenna portion can be attached to a substrate or the like, so that the antenna portion does not protrude greatly or is exposed to the outside.

Λ / (3 × εr ^1/2 ) ≦ L1, L2 ≦ λ /
(1.3 × εr ^1/2 ) λ / (30 × εr ^1/2 ) ≦ L3 ≦ λ / (4 × εr ^1/2 ) where λ is the free space wavelength at the center frequency when operating the antenna ( cm) and εr represent the relative dielectric constant of the substrate material.

In FIGS. 1, 2, and 3, reference numeral 2 denotes a rectangular radiation electrode formed on the main surface 1a of the substrate 1, and reference numeral 3 denotes a ground electrode formed on the main surface 1b of the substrate 1.

The radiation electrode 2 and the ground electrode 3 (hereinafter, abbreviated as respective electrodes) have a resistivity of 1 such as Ag, Au, Cu, and Pd.
× 10 ⁻⁴ Ωcm or less of a metal material alone, an alloy thereof, or another metal (Ti, Ni
Etc.) are used. Among these materials,
In particular, Ag or an alloy of Ag and another metal material is preferably used because it is very excellent in characteristics and workability when forming each electrode. Further, each electrode may be formed of one layer, or may be formed of two or more layers. That is, a film of another metal material is formed as a buffer layer between the substrate 1 and each electrode for the purpose of improving adhesion strength or the like, or for the purpose of protecting each electrode on each electrode. Alternatively, a metal material or a protective film having good corrosion resistance may be formed. Further, each electrode may contain at least one of oxygen, nitrogen and carbon as an impurity to such an extent that characteristics are not affected.

The electrodes and the like are formed by a printing method, a plating method, a sputtering method, or the like. In particular, when each electrode is formed to be relatively thin, it is preferable to use a sputtering method or a plating method, and when it is formed to be relatively thick, it is preferable to use a printing method. In the case of the present embodiment, the printing method is used because the productivity is good. Specifically, a paste in which metal particles such as Ag, a glass frit, a solvent, and the like were mixed was applied on the substrate 1 in a predetermined shape, and heat treatment was applied to form each electrode.

The thickness of each electrode is 0.01 μm to 50 μm.
μm (preferably 1 μm to 40 μm). When the film thickness of each electrode is 0.01 μm or less, the gain of the antenna may be reduced because it is thinner than the skin depth, and when the film thickness of each electrode is 50 μm or more, the electrode is easily peeled, In addition, problems such as an increase in cost occur. Furthermore, in the case of antennas for vehicles,
Preferably, the electrodes are formed in a range of preferably 1 μm to 40 μm so as to withstand use in a poor environment where vibration and impact always exist. By forming the electrode under such conditions, it is possible to reliably prevent the occurrence of peeling of the electrode and the like.

The shape of a general radiating electrode differs depending on the type of radio wave to be transmitted and received. In the case of a right-turn circularly polarized antenna, a degenerate separation element (triangular cutout) as shown in FIG. In addition to the rectangular shape having the shape, a rectangular shape as shown in FIGS. 4 to 6, an elliptical shape, a circular shape with a degenerate separation element, and a polygonal shape (a cross section of a triangle, a square, a pentagon,...・ ・)

Reference numeral 4a denotes a power supply pin, and the power supply pin 4a constitutes power supply means for transmitting and receiving right-handed circularly polarized waves.
Further, the power supply pin 4a is formed of a conductive material such as Fe or Cu, and further has a conductive metal film such as solder formed on the surface thereof in order to improve the bonding property with the radiation electrode 2 and the like. May be. Further, in order to improve the corrosion resistance and the like of the power supply pin 4a, a material having high corrosion resistance made of Au, Ni, Ti or the like may be coated.

The power supply pin 4 a is inserted into a through hole 1 d provided in the substrate 1, one end of which is electrically connected to the radiation electrode 2 and does not contact the ground electrode 3. Earth electrode 3
In order to reduce the probability of contact between the ground electrode 3 and the power supply pin 4a, a cutout portion 3a is provided in a portion of the ground electrode 3 around the through hole 1d. The power supply pin 4a and the radiation electrode 2 are fixed to the substrate 1 by bonding to each other with a conductive bonding material such as solder or a conductive organic bonding material.

Further, by adjusting the position at which the power supply pin 4a is provided (the center of the power supply pin 4a or the center of the through hole 1d), it is possible to prevent impedance mismatching of the antenna and prevent deterioration of characteristics. . That is,
Assuming that the center of the radiation electrode is the origin, the distance Z0 of the position of the feed pin to the origin preferably satisfies the following condition.

In the case of a rectangular radiation electrode with a degenerate separation element (notch) (FIG. 1), when the side length of the radiation electrode is Z1, Z0 ≦ 0.25 × Z1 In the case of a rectangular radiation electrode (FIG. 4) When the diagonal length of the radiation electrode is Z2, Z0 ≦ 0.30 × Z2 In the case of an elliptical radiation electrode (FIG. 5), the average value of the axial length Z31 in the elliptical direction and the axial length Z32 in the short circular direction of the radiation electrode Z0 ≦ 0.30 × Z3 In the case of a circular radiating electrode (FIG. 6) with a degenerate separation element (notch), when the side length of the radiating electrode is Z4, Z0 ≦ 0.25 × Z4 And so on. Since the shape of the radiation electrode is not limited to the above four types, it is not possible to cover all the shapes. However, by the above-described impedance adjustment, impedance matching at 50Ω normally designed in a high-frequency circuit can be performed. As a result, it is possible to prevent the loss due to the impedance mismatch of the antenna and prevent the deterioration of the transmission / reception characteristics.

Next, a method of adjusting the resonance frequency f0 will be described. The resonance frequency is determined by the dimensions of the radiation electrode, the thickness of the substrate, the relative dielectric constant, and the like, and generally follows the following equation.

In the case of a square L = C / (2 × F × √εr) In the case of a circle R = 1.841 × C / (2 × π × F × √)
εr) L is the side length of the rectangular radiation electrode, R is the radius of the circular radiation electrode, C
Is the speed of light, F is the resonance frequency, and εr is the relative dielectric constant of the substrate.

The above equation represents a rough dimension, and in practice, an optimum dimension can be obtained in consideration of effects such as the thickness of the substrate and the material characteristics of the dielectric.

For example, the resonance frequency f0 can be increased by shortening Z1 shown in FIG. 1. By increasing Z1, the resonance frequency f0 can be lowered. In order to increase the frequency bandwidth, the area of the degenerate separation element (notch) may be increased. However, if the degenerate separation element is too large, impedance matching cannot be achieved. Therefore, it is desirable that the size of the degenerate separation element be 20% or less, preferably 1% or more and 10% or less with respect to the area of all the radiation electrodes.

The same applies to the radiation electrodes of other shapes shown in FIGS. FIG. 4 is a front perspective view showing an antenna according to one embodiment of the present invention, FIG. 5 is a front perspective view showing an antenna according to one embodiment of the present invention, and FIG. 6 shows an antenna according to one embodiment of the present invention. It is a surface perspective view.

The case of the rectangular radiation electrode of FIG. 4 is as follows. That is, a square having a short side of the rectangle as one side is considered as a main radiation electrode, the other part is considered as a degenerate separation element, and a combination of the main radiation electrode and the degenerate separation element is considered as a total radiation electrode. At this time, the area of the degenerate separation element is not more than 20%, preferably 1% with respect to the area of all the radiation electrodes.
It is desirable to set it to 10% or more.

As described above, the degenerate separation element can be formed by notching as shown in FIG. 1 or by adding it as shown in FIG. For example, a degenerate separation element such as a rectangle or a triangle may be added to a square or circular main radiation electrode. At this time, the area of the degenerate separation element is 20% or less of all the radiation electrodes, preferably 1% or more and 10% or less, as in the above case.

In the case of the elliptical radiating electrode shown in FIG. 5, a circle having the short axis of the ellipse as one side is considered as the main radiating electrode, and the other parts are degenerated separation elements. The combination may be considered as a total radiation electrode. At this time, the area of the degenerate separation element with respect to the area of all the radiation electrodes is
It is desirable to set it to 20% or less, preferably 1% to 10% as in the case of a rectangular shape.

The case of the circular radiating electrode with the degenerate separation element (notch portion) shown in FIG. 6 is the same as that of FIG. 1, and the area of the degenerate separation element is 20% or less of the area of all the radiation electrodes. Preferably, it is desirable to be 1% or more and 10% or less.

The above description is an example of a right-handed circularly polarized antenna. In the case of a left-handed circularly polarized antenna, the insertion through-hole 1d for inserting the feed pin 4a is set to 90 around the center of the radiation electrode. It is provided at a position rotated by ゜ (or -90 °).
Others are the same as the right-handed circularly polarized waves.

In the case of linear polarization, there is provided a square, circular, elliptical, polygonal (triangular, quadrangular, pentagonal, etc.) electrode without a degenerate separation element for right-handed circularly polarized wave. Others are the same as the right-handed circularly polarized antenna.

Next, an example of attaching an antenna to a circuit board in this embodiment will be described with reference to FIG. FIG. 7 is a perspective view showing an antenna according to another embodiment of the present invention.

First, a feeder pin 4a is provided in a conductive flat plate 5 such as an iron plate, a copper plate, an aluminum plate or the like with a through hole sufficient for the power supply pin 4a to be electrically insulated therethrough.
is provided in the insertion hole of the circuit board 6 so that the conductive plate 5 is sandwiched therebetween.
Insert That is, the antenna is placed so that the ground electrode 3 and the circuit board 6 of the antenna face the conductive flat plate 5, respectively. Then, the power supply wiring formed on the surface of the circuit board 6 opposite to the side on which the antenna and the conductive flat plate are mounted and the power supply pin 4a are respectively bonded using a bonding material such as solder. At this time, in order to improve the mounting strength,
A double-sided tape or an organic adhesive may be provided between the antenna and the conductive flat plate and between the conductive flat plate and the circuit board. Also,
When the antenna and the circuit board are fixed to the conductive flat plate, a convex portion may be provided on the flat plate so that positioning can be performed easily and accurately. It is desirable that the convex portion is formed by half blanking, cutting and bending as shown in FIG. 8 in consideration of simplicity in manufacturing. The conductive flat plate can be omitted for the purpose of miniaturization. At this time, the directional characteristics of the antenna are close to non-directionality. For example, when incorporated in a mobile phone, omnidirectionality is often preferred, and it is more suitably used in combination with the small size. In addition, it is desirable that the circuit board be covered and shielded in a box shape using such a conductive flat plate, a magnetic flat plate, a composite flat plate, or the like so as not to be affected by external radio waves or radiation.

Next, another embodiment will be described with reference to FIG. First, a conductive plate 7 such as an iron plate, a copper plate, or an aluminum plate is provided with a through hole sufficient to accommodate the circuit board 6, and an insertion hole for inserting the power supply pin 4 a is provided in the circuit board 6. 7, the power supply pin 4 a of the antenna is inserted into the insertion hole of the circuit board 6 so as to face the ground electrode 3 of the antenna. That is, the antenna is placed so that the ground electrode 3 of the antenna and the circuit board 6 face each other inside the conductive flat plate 7. At this time, the circuit board must be sufficiently smaller than the antenna board 1 so that the circuit board and the conductive flat plate can be sufficiently fixed on the ground electrode surface of the antenna board. Then, the power supply wiring formed on the surface of the circuit board 6 opposite to the side on which the antenna is mounted is connected to the power supply pin 4a using a bonding material such as solder. At this time, a double-sided tape, an organic adhesive, or the like may be provided between the antenna and the conductive flat plate and between the antenna and the circuit board in order to improve the mounting strength. Further, providing a convex portion for fixing the antenna on the conductive flat plate is the same as in the above embodiment.

The antenna configured as described above is extremely small and high-performance, and has a performance suitable for transmitting and receiving wireless data by an artificial satellite capable of covering a wide transmitting and receiving area. Such a situation is shown in FIGS. Figures 10 and 1
FIG. 1 is a diagram showing transmission / reception characteristics of the antenna of the present invention.
It can be seen that the antenna has hemispherical directivity and high transmission / reception gain in a wide band. As described above, since the transmission / reception characteristics are very good, it is possible to perform good data exchange and the like, and it is extremely unlikely that a data transfer error occurs.

Next, an application example using the above-described antenna will be described. FIG. 12 is a diagram showing a radio receiving apparatus using an antenna according to an embodiment of the present invention.
In the figure, reference numeral 8 denotes an artificial satellite for transmitting data wirelessly, a wireless receiving device 9 having the above-mentioned antenna, a signal processing unit for processing received data to convert the data into audio and video signals, This is a wireless receiving device including a speaker, a display, and the like that output images.

In the radio receiving apparatus 9 configured as described above, the antenna can be made very small and the radio wave coming from the artificial satellite 8 can be efficiently received. Wireless receiver 9 in such a place
, Data communication can be reliably performed.

[0070]

According to the present invention, a ground electrode and a radiation electrode are provided on both surfaces of a substrate, respectively, and are electrically connected to the radiation electrode.
Power supply means is provided in non-contact with the ground electrode, and the power supply means transmits and receives radio waves composed of any one of right-handed circularly polarized light, left-handed circularly polarized light, and linearly polarized light (horizontally polarized light, vertically polarizedly polarized light). The size and performance of the antenna can be improved by appropriately selecting the conditions for forming the substrate element and the electrode within the range of the relative dielectric constant of 6 to 150 as the antenna substrate.

[Brief description of the drawings]

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

FIG. 2 is a rear perspective view showing the antenna according to the embodiment of the present invention;

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

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

FIG. 5 is a front perspective view showing an antenna according to an embodiment of the present invention.

FIG. 6 is a front perspective view showing an antenna according to an embodiment of the present invention.

FIG. 7 is a perspective view showing an antenna according to another embodiment of the present invention.

FIG. 8 is a perspective view showing an antenna according to another embodiment of the present invention.

FIG. 9 is a perspective view showing an antenna according to another embodiment of the present invention.

FIG. 10 is a diagram showing transmission / reception characteristics of the antenna according to the present invention;

FIG. 11 is a diagram showing transmission / reception characteristics of the antenna of the present invention.

FIG. 12 is a diagram showing a wireless reception device using an antenna according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 1a, 1b Main surface 1c Corner 1d Through-hole 2 Radiation electrode 3 Ground electrode 3a Notch 4a, 4b Feeding pin 5,7 Conductive flat plate 6 Circuit board 8 Artificial satellite 9 Radio receiver

 ──────────────────────────────────────────────────の Continued on the front page (72) Atsushi Yoshinomoto, Inventor 1006 Kadoma, Kazuma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Yoshio Onaka 1006, Kadoma, Kazuma, Kadoma, Osaka Pref. In-company (72) Inventor Takuya Fujimaru 1006 Kadoma, Kadoma, Osaka Pref.F-term (reference) in Matsushita Electric Industrial Co., Ltd. NA06 5J046 AA03 AA05 AA07 AA19 AB03 AB13 PA07 TA05 UA08

Claims (14)

[Claims] A substrate, a radiating electrode provided on one main surface of the substrate, a ground electrode provided on the other main surface of the substrate, and an earth electrode electrically connected to the radiating electrode. Is an antenna provided with a power supply means provided in a non-contact manner. 2. The antenna according to claim 1, wherein the relative permittivity εr of the substrate is 6 or more and 150 or less. 3. The substrate material is forsterite ceramic, alumina ceramic, calcium titanate ceramic, magnesium titanate ceramic, zirconia-tin-titanium ceramic, barium titanate ceramic, lead-calcium-zirconia ceramic. ceramic,
3. The antenna according to claim 1, wherein the antenna is made of at least one material selected from the group consisting of a lead-calcium-iron-niobium ceramic and a lead-calcium-magnesium-niobium ceramic. 4. The antenna according to claim 1, wherein the surface roughness of the substrate is 10 μm or less. 5. The method according to claim 1, wherein the substrate is made of ceramic and has a sintered density of 92% or more.
4. The antenna according to any one of 4. 6. A chamfering process, a tapering process, and the like at a corner of a substrate.
The antenna according to claim 1, wherein at least one of step processing is performed. 7. The antenna according to claim 6, wherein the C chamfering is adopted as the chamfering, and R of the C chamfering is set to 0.1 mm or more. 8. A power supply pin is used as a power supply means, a through hole is provided in a substrate, the power supply pin is inserted into the through hole, the power supply pin and the radiation electrode are joined, and the power supply pin and the ground electrode are not in contact with each other. The antenna according to any one of claims 1 to 7, wherein: 9. The low-noise amplifier substrate, comprising: the antenna according to claim 1; and a substrate that contacts the ground electrode of the antenna to hold the antenna and that forms a low-noise amplifier circuit on the back side. An antenna characterized by comprising a coaxial cable for supplying power to and supplying input / output signals to and from the antenna. 10. The antenna according to claim 1, further comprising: a flat plate for holding said antenna in contact with a ground electrode of said antenna; and a low-noise amplifier substrate on the other back side of said flat plate. And a coaxial cable for supplying power to the low-noise amplifier board and transmitting and receiving input / output signals. 11. A positioning projection for fixing the antenna according to claim 1 is provided on one surface of said flat plate, and said low noise amplifier board is fixed on the other surface of said flat plate. The antenna according to claim 9, further comprising a positioning protrusion. 12. A double-sided tape when fixing the antenna according to claim 1 on one surface on the flat plate and fixing the low-noise amplifier board on the other surface on the flat plate. The antenna according to any one of claims 9 to 11, wherein an organic adhesive is used. 13. An opening is provided on the flat plate so that the low-noise amplifier board can be directly fixed to the antenna according to any one of claims 1 to 8, and further, on one surface of the flat plate.
A projection for positioning when fixing the antenna according to claim 8 is provided, and a double-sided tape or an organic adhesive is used when fixing the flat plate and the antenna according to claim 1 to 8. An antenna according to claim 9. 14. The antenna according to claim 9, wherein said low-noise amplifier board is covered with a box-shaped shield case made of a good conductor such as metal.