JPH02246502A - Antenna - Google Patents

Abstract

PURPOSE: To make an electronic device employing the antenna small in size and light in weight by directly metallizing an antenna element and a feeding part onto an antenna support molded from a plastic material. CONSTITUTION: The antenna 10 comprises a truncated conical shaped antenna support 12 molded from a plastic material, an antenna element provided to an outer side of the antenna support 12 and a feeding part 18. The antenna element comprises a conductor spiral wire 70 provided to an outer side wall 14 of the antenna support 12 and a ring shaped ground plane 72 provided to a bottom side of the antenna support 12. One end of the conductor wire 70 and the feeding part 18 are integrally metallized to the antenna support 12 continuously and the ground plane 72 is also metallized. Thus, the antenna element, the feeding part, a balance-unbalance conversion circuit and an amplifier or the like are integrated and the electronic device employing the antenna is made small in size and light in weight.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an antenna molded from a plastic material, in which the antenna element part and the feed part are directly metallized on the plastic material.

~ Conventional technology Various antennas are used to receive radio waves of various wavelengths, but helical antennas and Yagi-Uda are linear antennas suitable for receiving radio waves of frequencies from several hundred megahertz to several tens of gigahertz. Examples of the antenna include a strip antenna, a super pattern style antenna, a notch antenna, etc. as a plate antenna. Broadcasting satellites, Global Positioning System (GPS), and car-mounted phones use radio waves at the frequencies mentioned above, and in order to make antennas smaller and lighter, it is recommended to use helical antennas or strip antennas. Are suitable.

A helical antenna usually has one or more conductor wires wound in a hollow spiral shape or spirally around the outer surface of a circular tube, and is fed with power through a feeding point. A coaxial line is mainly used as the external power supply line. Impedance matching between the helical antenna and the external feed line and balance-unbalance of the circuit can be solved by known methods. The external feed line is further connected to an amplifier or the like.

A patch antenna, which is a type of strip antenna, usually has a rectangular or circular patch pattern on the front surface of an insulating flat plate, has a ground plate on the back surface, and is supplied with power through a power feeding point provided on the patch pattern. For example, when a coaxial line is used as the external power supply line, the center conductor of the coaxial line is connected to a power supply point, and the outer conductor is connected to a ground plate for power supply. The external feed line is further connected to an amplifier or the like. The batch pattern and the ground plate of the batch antenna are usually formed by pasting a punched metal foil coated with adhesive with an insulating plate, or by etching a laminated plate with metal foil pasted together.

Problems to be Solved by the Invention A helical antenna in which a conductor wire is wound in a hollow helical shape has a problem in that the helical shape is easily changed by vibration or external force, and the antenna characteristics are easily changed. A helical antenna, in which a conductor wire is spirally wound around the outer surface of a circular tube, is durable against vibrations and external forces.

However, when the conductor wire is bonded to the outer surface of the circular tube with an adhesive, there is a problem that if the environment in which the antenna is used is harsh, the adhesive deteriorates and the conductor wire peels off from the outer surface of the circular tube. Even when the conductor wire is thermally transferred to the outer surface of the circular tube, the conductor wire may peel off from the outer surface of the circular tube depending on the environment in which the antenna is used. If the outer surface of the circular tube has protrusions, it is difficult to wrap the conductor wire around the outer surface of the circular tube. Furthermore, the winding in the antenna manufacturing process tends to cause variations in antenna characteristics due to variations in pitch and the like.

When the helical antenna is a balanced type and uses a coaxial line for power feeding, a balanced-unbalanced conversion circuit must be inserted between the helical antenna and the coaxial line. Equilibrium -
Examples of unbalanced conversion circuits include Supertop and λ/4
One example is a balun using a branch conductor, but providing such a separate circuit increases the antenna manufacturing cost and complicates the antenna assembly work. Normally, an antenna, an amplifier, etc. are separate, but in order to further reduce the size and weight of electronic equipment, it is desirable to use a helical antenna in which the amplifier, etc. can be integrated into the antenna. However, with conventional combinations of helical antennas and amplifiers, it is difficult to integrate them.

Conventional batch antennas are manufactured by bonding metal foil and insulating plates together or by etching a laminate, so the antenna must have a flat shape. When the antenna shape is flat, the directivity of the antenna becomes narrow.

If the antenna is required to have wide-angle directivity, it is necessary to provide the batch pattern of the batch antenna on a curved surface.

Therefore, it is necessary to form the antenna into a three-dimensional shape having a curved surface, but it is difficult to form a conventional batch antenna into a three-dimensional shape.

When the dielectric constant of the insulator of the batch antenna is C, the resonant frequency λ' of the antenna holds the following relationship: λ'=λ/,rl-. Here, λ is the wavelength of the radio wave. Therefore, the size of the batch pattern of the batch antenna becomes smaller in proportion to 1/FT as ε becomes larger. However, the antenna gain of the batch antenna becomes smaller as the aperture of the batch antenna becomes smaller. Therefore, the smaller the dielectric constant ε of the insulator of the batch antenna,
The aperture of the batch antenna can be increased, and the antenna gain of the batch antenna can be increased.

Further, in order to further reduce the size and weight of electronic equipment, it is desirable that the batch antenna be able to integrate the batch antenna and an amplifier.

An object of the present invention is to provide an antenna that will not be deformed or damaged even under harsh usage environments.

An object of the present invention is to provide an antenna in which an antenna element and a feed section are provided on an antenna support without using an adhesive.

Another object of the present invention is to provide an antenna with high antenna gain and wideband characteristics.

Furthermore, the present invention provides an antenna in which the antenna support can have any three-dimensional shape.

Furthermore, the object of the present invention is to provide an antenna element, a feed section, a balanced
An object of the present invention is to provide an antenna in which an unbalanced conversion circuit, an amplifier, etc. can be easily integrated.

A further object of the present invention is to provide an antenna that has low manufacturing costs, little variation in characteristics, and can greatly simplify the assembly process.

The antenna of the present invention is an antenna consisting of an antenna support molded from a plastic material, an antenna element provided on the support, and a power feeding part, wherein the antenna element and the power feeding part are provided on the support. It is characterized by being directly metalized.

The antenna can be of various types, such as a helical antenna, a microstrip antenna, a patch antenna, etc.

The shape of the antenna element can be linear or planar.

The feed section consists of a feed point provided on the antenna element, or a feed line connection portion provided on the antenna support, and a conductor that conducts the feed point provided on the antenna element, the feed line connection portion, and the feed point. . The power feeding section can include a balanced-unbalanced conversion circuit and an impedance matching circuit. The antenna element may be provided with one or more feeding points.

The antenna element and the feed section can be provided on the outer surface of the antenna support, or can be provided on the inner surface of the antenna support facing the hollow part if the antenna support is hollow.

Metallization can be performed by metal vapor deposition, conductive paste, electroless plating, or electrolytic plating, and among these, electroless plating or electrolytic plating is preferably used.

A coaxial line, a strip line, a coplanar line, etc. can be used as the external power supply line, and a power supply section suitable for the external power supply line can be provided.

If necessary, an amplifier or the like can be incorporated into the antenna.

When the antenna is a helical type, the shape of the antenna support can be determined depending on the required characteristics of the helical antenna, such as cylindrical, conical, truncated conical, spherical, or hemispherical. The dimensions of the antenna support are determined by the required helical antenna characteristics. The antenna element can be a helical conductor wire or a combination of a helical conductor wire and a ground plane. The number of spiral conductor wires constituting the antenna element, the helical pitch, and the length and width of the conductor wires are determined by the antenna gain, directivity, and other characteristics required of the helical antenna.

When the antenna is a patch antenna, the antenna support can have a first surface made of a curved surface and a second surface made of a curved surface or a flat surface opposite to the first surface. The antenna element consists of a patch pattern provided on the first surface and a ground plane provided on the second surface.

Another shape of the antenna support of the patch antenna includes a first portion having a curved surface or a flat surface, and a curved surface or a flat surface opposite to the curved surface or the flat surface of the first portion! 2, and a support part that connects the first part and the second part, with a space provided between the first part and the second part, and having a shape. I can do it. The antenna element includes a patch pattern provided on the curved surface or plane of the first portion, and a ground plane provided on the curved surface or plane of the second portion. Although it is desirable that the antenna element and the ground portion face the above-mentioned space, they may be provided on a curved surface or a flat surface that does not face the above-mentioned space. The spatial distance between the first part and the second part is determined by the required antenna characteristics.

The curved surface of the antenna support of the batch antenna can be, for example, a spherical surface, an ellipsoid of revolution, a paraboloid of revolution, etc., and this curved surface can be determined depending on the required antenna characteristics. In order to obtain the microstrip effect, the patch pattern and the ground plane need to be opposite. The overall shape and size of the antenna support of the patch antenna can be any shape depending on the location where the antenna is installed and the shape of the device incorporating the antenna.

The shape of the patch pattern is preferably rectangular, circular, or crank type. The size of the patch pattern depends on the required antenna characteristics.

Further, a plurality of patch patterns may be provided on the first surface of the antenna support or the surface of the first portion. The shape and size of the ground plane are arbitrary as long as a microstripe effect can be obtained between the ground plane and the patch pattern.

The antenna of the present invention will be explained below with reference to the drawings.
Like reference numbers in the drawings represent like parts.

First, a case where the antenna of the present invention is a helical antenna will be explained. In the following description, the feed line is assumed to be coaxial, but is not limited to this.

FIG. 1 is a perspective view of a helical type antenna 10 of the present invention. FIG. 2 is a cross-sectional view of the antenna 1O along the line ■-■ in FIG.

The antenna IO consists of a frusto-conical antenna support 12 molded from a plastic material, an antenna element and a feed section 18 provided on the outer surface of the antenna support 12. The antenna element includes one spiral conductor wire 70 provided on the outer side wall 14 of the antenna support 12 and a ring-shaped ground plane 72 provided on the bottom surface of the antenna support 12.
It consists of In FIG. 1, one end of the conductor wire 70 and the power feeding section 18 are continuously metallized as one body (
Below, the metallized parts are illustrated with lattice hatching),
The power feeding unit 18 is a power feeding point. The ground plane 72 is also metallized. The antenna support 12 can be provided with a central hole 20 for inserting a coaxial cable, if desired.

The center conductor of the coaxial cable is inserted into the center hole 20 and electrically connected to the power supply section 18 by brazing or soldering, for example. The outer conductor of the coaxial cable is electrically connected to the ground plane 72 by an appropriate method such as brazing or soldering. This allows the antenna to be powered by the coaxial cable.

FIG. 3 shows another example of a helical type antenna of the present invention, and is a sectional view of the antenna IO.

The antenna 10 consists of a hollow truncated conical antenna support molded from a plastic material, an antenna element, and a feed section. The antenna support includes a first antenna support 12 in which a truncated conical side wall and a top surface are integrally formed.
A and a generally circular second antenna support 12B forming a frustoconical bottom surface. A notch for fitting the second antenna support 12B can be provided in the bottom inner side wall portion of the first antenna support 12A. The antenna element includes one spiral conductor wire 70 provided on the inner side wall surface 14 facing the hollow portion of the first antenna support 12A, and one spiral conductor wire 70 provided on the outer surface of the second antenna support 12B. It consists of a ring-shaped ground plane 72. A power supply section 18 is provided at a lower portion of the inner side wall surface 14. In FIG. 3, one end of the conductor wire 70 and the power supply section 18 are continuously metallized together, and the power supply section 18 is a power supply point. The ground plane 72 is also metallized. A protrusion 2 is formed on the inner side wall surface 14 of the first antenna support 12A.
2, and a hole 24 for inserting and fixing a coaxial cable or a coaxial connector into the protrusion.

A coaxial wire is inserted into the hole 24, and the center conductor of the coaxial wire is electrically connected to the power supply section 18 by, for example, brazing or soldering.

Next, the antenna support 12A is fixed to the antenna support 12B. The fixing method is to use adhesive, a small threaded hole is provided in the bottom of the first antenna support 12A, and a second antenna support 12B is attached opposite to this small hole.
A small through hole is provided in the part, and the first and second
A method for fixing an antenna support, a projection is provided on the outer peripheral edge of the second antenna support 12B, a recess that fits with the projection is provided in the lower part of the inner side wall surface 14 of the first antenna support 12A, Any method may be used to fix the first antenna support 12A and the second antenna support 12B in a snap manner. The coaxial outer conductor and the ground plane 72 are electrically connected by an appropriate method such as brazing or soldering. This allows the antenna to be powered from the coax. FIG. 4 is a bottom view of the antenna support 12A of the antenna shown in FIG.

The antenna element is a linear antenna element composed of a spiral conductor wire, and when there are two or more linear antenna elements, the antenna usually forms a balanced circuit. When connecting such an antenna to an unbalanced coax, it is necessary to provide a balanced-unbalance conversion circuit between the linear antenna element and the coax.

Although there are various types of balanced-unbalanced conversion circuits, an antenna provided with a power feeding section having a balun is illustrated in FIGS. 5 to 7. The balun is provided in the inner wall 26 of the hole 24 for mounting the coax.

FIG. 5 is a perspective view of a helical type antenna IO of the present invention provided with a power feeding section having a balun, and FIG. 6 is a sectional view taken along line Vl-VI in FIG. 5.

The antenna 10 includes a hollow cylindrical antenna support 12 molded from a plastic material;
It consists of two spiral-shaped linear antenna elements 16A and 16B provided on the inner side wall surface 14 facing the hollow part, and power feeding parts 18A and 18B provided on the lower part of the inner side wall surface 14. In FIG. 6, one end of the linear antenna element 16A and the feed section 18A, and the linear antenna 16B and the feed section 18B are continuously metallized as one body. The power feeding unit 18A has a power feeding point. A protrusion 22 is provided on the inner side wall surface 14 of the antenna support 12, and a hole 2 is provided for inserting and fixing a coax into the protrusion 22.
4 are provided.

FIG. 7 shows an enlarged sectional perspective view with a portion of the protrusion 22 cut away. The power supply unit will be described in detail below with reference to FIG.

The power feeding section 18A includes a conductor 30A extending from one end of the antenna element 16A and a conductor 32A provided on the top surface of the protrusion 22.
, a conductor 34A provided on the upper part of the inner wall 26 of the hole 24, and a conductor 36 provided on the lower part of the inner wall 26. These conductors are integrally metallized. Power supply section 18
B is a conductor 30B extending from one end of the antenna element 16B.
, a conductor 32B provided on the top surface of the protrusion 22, and a hole 24.
The conductor 34B provided on the upper part of the inner wall 26 and the inner wall 26
A conductor 36 is provided at the bottom of the conductor 36.

These conductors are integrally metallized. Power supply part 1
The end conductor 36 of 8A and the end conductor 36 of the power feeding section 18B are integrated, and the conductor 36 is a power feeding line connection section.

Conductors 32A and 32B are separated by two diametrically opposed slits 38A and 38B of hole 24 (slit 38B is not shown in FIG. 7). Slits 38A and 38B further extend parallel to the axial direction of hole 24 into inner wall 26 of hole 24, separating conductors 34A and 34B. The length of the slits 38A and 385B in the inner wall 26 portion is approximately λ/4 (1/4 wavelength).

By providing such a slit with a length of approximately λ/4 in the inner wall 26 of the hole 24, a balun, which is a balanced-unbalanced conversion circuit, is formed in the power feeding sections 18A and 18B. The widths of slits 38A and 38B can be determined by impedance matching conditions between the antenna element and the feed line.

The coaxial cable or coaxial connector is the coaxial hole 24
You can fix the coax by inserting it into the The coaxial center conductor is electrically connected to the conductor 32A of the power supply section 18A by brazing or soldering, for example. To facilitate this task, a cutout 28 can be provided in the antenna support 12 diametrically opposed to the feed section 18A.

By inserting the coax into the hole 24, the outer conductor of the coax is inserted into the hole 24! ! It is electrically connected to a conductor 36 provided at the bottom of 26. This allows the antenna to be powered from the coax.

FIG. 8 is a cross-sectional view of the helical type antenna IO of the present invention, which is provided with a feeding section having a balanced-unbalanced conversion circuit of a different type from the balanced-unbalanced conversion circuit shown in FIGS. 5 to 7. It is. In FIG. 8, the protrusion 22 is also shown in cross section.

The antenna 10 includes a hollow cylindrical antenna support 12 molded from a plastic material;
Three spiral-shaped linear antenna elements 16A, 116B and 16 provided on the inner side wall surface 14 facing the hollow part
8 (linear antenna elements 16B and 16c are not shown in FIG. 8), and feeding portions 18A, 18B, and 18G provided at the lower part of the inner side wall surface 14.

In FIG. 8, one end of the linear antenna element 16A, a feeding section 18A, one end of the linear antenna element 16B, and the feeding section 1 are shown.
8B, one end of the linear antenna element 16G and the feed section 18G are continuously metallized as one body. The power feeding unit 18A has a power feeding point. The inner side wall surface 14 of the antenna support 12 is provided with a protrusion 22 and a hole 24 for inserting and securing the coax within the protrusion.

The power feeding section 18A includes a band-shaped conductor 40A and a conductor 30A that connects the band-shaped conductor 40A and the antenna element 16A. These conductors are integrally metallized. The power feeding section 18B includes a rectangular conductor 40B provided in parallel to the strip conductor 40A, a conductor 32 provided on the top surface of the protrusion 22, a conductor 36 provided on the inner wall 26 of the hole 24, an antenna element 16B, and a rectangular conductor 40B. It consists of a conductor 30B that connects the conductor 40B, and a conductor 30B' that connects the rectangular conductor 40B and the conductor 32. These conductors are integrally metallized. The power feeding part 18c includes a rectangular conductor 40G provided in parallel to the strip conductor 40A, and a conductor 32 (provided on the top surface of the protrusion 22).
This is common to the conductor 32 of the power supply part 18B) and the hole 2
4 (this is a conductor 36 provided on the inner wall 26 of power supply section 1
(It is common to the conductor 36 of 8B and is the feed line connection part)
, a conductor 30C connecting the antenna element 16c and the rectangular conductor 40C, and a conductor 30C'' connecting the rectangular conductor 40G and the conductor 32. These conductors are integrally metallized.

Strip conductor 40A, rectangular conductor 40B1, and strip conductor 4O
A and rectangular conductor 40C are slits 38A and 38B.
separated by. Slits 38A and 38B are generally parallel to the axial direction of hole 24. The length of slits 38A and 38B is approximately λ/4 (1/4 wavelength).

By providing such a slit with a length of approximately λ/4 on the inner surface 14 of the antenna support 12, a balanced-unbalanced conversion circuit is formed in the feed portions 18A, 18B, and 18c. The widths of slits 38A and 38B can be determined by impedance matching conditions between the antenna element and the feed line.

The coaxial cable or coaxial connector is the coaxial hole 24
You can fix the coax by inserting it into the The coaxial center conductor is electrically connected to the strip conductor 40A by, for example, brazing or soldering. Insertion into the coaxial hole 24 electrically connects the coaxial outer conductor to a conductor 36 provided at the bottom of the inner wall 26 of the hole 24 . This allows the antenna to be powered from the coax.

FIG. 9 shows a cross-sectional view of the antenna IO shown in FIG. 8 in which the amplifier 60 is incorporated. In FIG. 9, an amplifier 60 is secured in any suitable manner on the inner side wall surface 14 of the hollow cylindrical antenna support 12 above the protrusion 22. In FIG.

The inner side wall surface 14 has three spiral linear antenna elements 16A, 16B, 16C (16B, 16c in FIG. 9).
(not shown), three power supply parts 18A, 18B,
18G is provided.

The signal input terminal of the amplifier 60 and the strip conductor 4 of the power feeding section 18A
0A can be connected using, for example, a gold wire. Conductors 30B' and 30C' are provided to generally surround amplifier 60.

Each of the ground terminals on the signal input side of the amplifier 60 is connected to the conductor 30
Gold wire can be used to connect B' and 30C'. Each of the ground terminals on the signal output side of amplifier 60 may also be connected to conductors 30B' and 30C' using gold wire. The output terminal of the amplifier 60 can be connected to the strip conductor 40A' provided above the top surface of the hole 22 by a gold wire. The coaxial center conductor is a strip conductor 40A'
For example, connect electrically by brazing or soldering.

By inserting the coax into the hole 24, the outer conductor of the coax is electrically connected to the conductor 36 on the inner wall 26 of the hole 24. Since the conductor 36 of the inner wall 26 and the conductor 30B''3QC' are integrally metallized, the coaxial outer conductor and the conductor 30B
'30C'' is electrically connected.

The amplifier 60 can be driven by, for example, providing a through hole in the antenna support portion where the amplifier 60 is installed and pulling out a lead wire through the through hole from a terminal provided on the bottom surface of the amplifier facing the antenna support, or By forming a through-hole circuit on the body by metallization and soldering the through-hole circuit to a terminal provided on the bottom of the amplifier 60, it is possible to connect to an external electronic device.

FIG. 9A shows a modification of the antenna shown in FIG. An amplifier 60 is mounted on the inner sidewall surface 14 of the antenna support and below the protrusion 22 . amplifier 60
Another protrusion 22' having a hole 24' is provided on the lower inner side wall surface 14 of. Inner wall 2 of hole 24 of protrusion 22
6 is provided with the balanced-unbalanced conversion circuit explained based on FIG. Insert the coaxial connector into hole 24,
One of the center conductors of the coaxial connector is connected to conductor 30A. The outer conductor of the coaxial connector is connected to a conductor 36 provided on the inner wall 26 of the hole 24. The other center conductor of the coaxial connector and the signal input terminal of the amplifier 60 are connected using a gold wire or the like. Coaxial connector outer conductor and amplifier 60
Connect the ground terminal on the signal input side of the terminal using a gold wire, etc.

Insert another coaxial connector into hole 24' of protrusion 22',
The center conductor of this coaxial connector and the signal output terminal of the amplifier 60, and the outer conductor of the coaxial connector and the ground terminal on the signal output side of the amplifier 60 are connected using a gold wire or the like.

As an alternative to this, conductors 36 of power feeds 18B and 18G
may extend further down from the inner wall 26 of the hole 24 and over the inner sidewall surface 14 to generally surround the amplifier 60 and even to the inner wall of the hole 24''.

In the antenna shown in FIG. 8, the coaxial attachment protrusion 22 and the feeding point are located at the lower part of the inner side wall surface of the antenna support. FIG. 1O illustrates another example of the helical type antenna of the present invention. FIG. 1O is a cross-sectional view of the antenna 10 taken along the line X--X in FIG. 11, in which the coaxial mounting protrusion 22 is provided on the upper end surface 44 inside the antenna support. FIG. 11 is a bottom view of the antenna of FIG. 1O (antenna element not shown).

The antenna IO includes a hollow cylindrical antenna support 12 molded from a plastic material;
Three spiral-shaped linear antenna elements 16AS 16B and 1 provided on the inner side wall surface 14 facing the hollow part.
6c (16c is not shown in FIG. 1O) and a power supply section 18A provided at the upper part of the inner side wall surface 14.
% 18B and 18C. In FIG. 1O, one end of the linear antenna element 16A, the feeding section 18A, the linear antenna 16B, the feeding section 18B, and the linear antenna element 1 are shown.
6c and the power feeding section 18G are continuously metallized and integrated. The power feeding unit 18A has a power feeding point. A cylindrical projection 2 is provided at the center of the inner upper end surface of the antenna support 12.
2 is provided, and a hole 24 for inserting and fixing the coax into the protrusion 22 is provided. Preferably, the hole 24 is concentric with the antenna support. A small hole 42 into which a coaxial center conductor is inserted is provided at the center of the upper end surface 44 of the antenna support 12.

The power feeding section 18A is a conductor 42A provided on the inner wall of the hole 42.
and a conductor 30A provided on the inner side surface 14 and the upper end surface 44 to connect one end of the antenna element 16A and the conductor 42A.

A hole 46A is provided in the protrusion 22, and the inner wall of the hole 46'A, the conductor 30A, and the conductor 42A are integrally metallized.

The power feeding section 18B includes a conductor 34B provided at the upper part of the inner wall 26 of the hole 24 of the protrusion 22, a conductor 36 provided at the lower part of the inner wall 26, and a conductor 30B connecting one end of the antenna element 16B and the conductor 34B. Consisting of The protrusion 22 has a hole 46
B is provided, the inner wall of the hole 46B, the conductor 30B1 the conductor 34
The B1 conductor 36 is integrally metallized.

The power feeding part 18c includes a conductor 34C provided at the upper part of the inner wall 26 of the hole 24 of the protrusion 22, and a conductor 36 provided at the lower part of the inner wall 26 (this is common to the conductor 36 of the power feeding part 18B, and is connected to the power supply line). ), the antenna element 16c
The conductor 30C connects one end of the conductor 34C to the conductor 34C. The protrusion 22 is provided with a hole 46C, and the inner wall of the hole 46C,
Conductor 30C1 Conductor 34C1 Conductor 36 is integrally metallized (the conductor on inner wall 26 of hole 24 is not shown in FIG. 11).

The conductors 34B and 34C are arranged in two slits 38A and 3, which are opposite to each other in the diameter direction of the hole 24 and parallel to the axial direction of the hole 24.
8B (slit 38B not shown in FIG. 1O). The length of slits 38A and 38B is approximately λ/4 (1/4 wavelength).

By providing such a slit with a length of approximately λ/4 in the inner wall 26 of the hole 24, a balanced-unbalanced conversion circuit is formed in the power feeding portions 18AX 18B and 18G. The widths of slits 38A and 38B can be determined by impedance matching conditions between the antenna element and the feed line.

The coaxial cable or coaxial connector is the coaxial hole 24
You can fix the coax by inserting it into the The coaxial center conductor is inserted into the small hole 42 of the power supply section 18A, and electrically connected by brazing or soldering, for example. Insertion into the coaxial hole 24 electrically connects the coaxial outer conductor to a conductor 36 provided at the bottom of the inner wall 26 of the hole 24 . This allows the antenna to be powered from the coax.

Next, a case where the antenna of the present invention is a patch antenna will be explained.

FIG. 12 is a perspective view of the antenna 100 of the present invention.

FIG. 13 is a sectional view taken along line xm-xm in FIG. 12. The antenna support 112 has a shape obtained by cutting a solid sphere molded from a plastic material with a plane, and has a first surface 114 made of a spherical surface and a second surface 116 made of a plane.
has. The first surface 114 and the second surface 116 face each other with the antenna support 112 in between. First surface 11
A through hole 118 is provided in the antenna support 112 perpendicularly to the second surface 116 from the top of the antenna support 112 .

The antenna element comprises a circular patch pattern 130 provided on the first surface 114 and a circular ground plane 140 provided on the second surface 116 . The ground plane 140 extends to the lower inner wall 120 of the through hole l18. In the antenna shown in FIG. 12, the feed section 150 has patch pattern 1.
30, and serves as a power feeding point. The power feeding section 130 and the ground plane 140 are metallized.

The center conductor of the coaxial cable, which is the power supply line, is inserted into the through hole 118.
It is electrically connected to the power supply unit 150 by brazing or soldering, for example. The outer conductor of the coaxial cable is passed through the hole 11.
8 on the lower inner wall 120 of the ground plane 1 in an appropriate manner.
electrically connected to 40. Thereby, the antenna is fed with power from the feed line.

14 is a sectional view showing a modification of the antenna shown in FIG. 12, and FIG. 15 is a bottom view of the antenna shown in FIG. 14.

A hole 12 is provided on the second surface 116 of the antenna support 112.
A protrusion 122 having a diameter of 4 is provided.

The power feeding unit 150 includes a conductor 1 provided on the second surface 116.
52, and a conductor 154 that is provided on the inner wall of the through hole 118 and connects the patch pattern 130 and the conductor 152. The inner wall 126 of the hole 124 of the protrusion 122 is the ground plane 140
It is integrally metallized. Conductor 152 and ground plane 1
40 is insulated.

Insert the coax into hole 124 and secure the coax. The coaxial center conductor and the conductor 152 are connected by brazing or soldering.

The coaxial outer conductor is electrically connected to the ground plane 140 by contacting the inner wall 126 of the hole 124 . In this way, the antenna is fed from the feed line.

FIG. 16 is a sectional view of an antenna that is a modification of the antenna 100 of the present invention shown in FIG. 12. The antenna support is
It has a first surface made of a spherical surface and a second surface made of a spherical surface.

FIG. 17 is a perspective view of a patch antenna having a different shape from the antennas of the present invention illustrated in FIGS. 12 to 16. FIG. 18 is a sectional view taken along line X--X in FIG. 17.

The antenna support 212 of the antenna 200 includes a first portion 214 having a rectangular flat plate shape and a second portion 216 having a rectangular flat plate shape.
and a support portion 218 that connects the first portion 214 and the second portion 216.

There is a space 2 between the first part 214 and the second part 216.
24 are provided, a first portion 214 and a second portion 216
and is opposite to each other with a space 224 in between.

The antenna element is provided on a patch pattern 230 of a crank tube provided on a surface of the first portion 214 that does not face the space 224 and on a surface of the second portion 216 that does not face the space 224. It consists of a rectangular ground plane 240. The support portion 218 includes a portion from the first portion 214 to the second portion 2.
1.6 is provided with a through hole 220 passing through it. The ground plane 240 extends to the lower inner wall 222 of the through hole 220 .

In the patch antenna shown in FIG. 17, the power feeding section 250 is formed in a part of the patch pattern 230. Batch pattern 230 and ground plane 240 are metallized.

The center conductor of the coaxial cable, which is the power supply line, is inserted into the through hole 220.
It is electrically connected to the power supply section 250 by brazing or soldering, for example. The outer conductor of the coaxial cable is inserted into the through hole 22.
0 on the lower inner wall 222 of the ground plane 2 in an appropriate manner.
electrically connected to 40. Thereby, the antenna is fed with power from the feed line.

The antenna shown in FIGS. 19 and 20 is
, 18 is a modification of the antenna illustrated in FIG.

FIG. 19 shows a cross-sectional view of the antenna, and FIG.
FIG. 9 is a bottom view of the antenna of FIG. 9;

The antenna support 212 of the antenna 200 includes a first portion 214 having a spherical surface, a second portion 216 having a disk shape,
It consists of a support part 218 that connects the first part 214 and the second part 216. First part 214 and second part 2
A space 224 is provided between the first portion 21 and the first portion 21 .
4 and the second portion 216 are opposed to each other with a space 224 in between.

The second portion 216 has a surface 216A facing the space 224.
Two through holes 242 and 2 are provided on the surface 216B not facing from the
52 are provided. A protrusion 226 with a hole 228 for fixing the coax is provided on the surface 216B.

The antenna element includes a circular patch pattern 23 provided on a surface 214A of the first portion 214 facing the space 224.
0 and the surface 216 of the second portion 216 facing the space 224
It consists of a circular ground plane 240 provided on A. 1st
The power feeding section 250A includes a conductor 254 provided on the surface 216B of the second portion not facing the space 224, and a conductor 256 connecting the patch pattern 230 and the conductor 254. The conductor 256 is provided on the support portion 218 and further extends along the inner wall of the through hole 252 . Conductor 254 and conductor 25
6 and is integrally metalized. batch pattern 2
30 and the power feeding section 250A are integrally metallized. The second power feeding section 250B includes a conductor 246 provided on the inner wall of the hole 228 and a conductor 244 connecting the conductor 246 and the ground plane 240 through the through hole 242. conductor 2
44 and the conductor 246 are integrally metallized. The second power feeding section 250B and the ground plane 240 are integrally metallized.

A hole 228 provided in the protrusion 226 connects the coaxial feed line.
The coaxial center conductor is electrically connected to the conductor 254 of the first power feeding section 250A by, for example, brazing or soldering. The coaxial outer conductor communicates with the inner wall of hole 228. Thereby, the antenna is fed with power from the feed line. If the impedances of the antenna and the coax are mismatched, impedance matching can be achieved by, for example, making part of the conductor 244 and the conductor 254 on the surface 216B parallel to provide an appropriate distance between the conductors. I can do it.

FIG. 21 is a bottom view of antenna 200 with amplifier 260 on surface 216B of the second portion of the antenna of FIG. 19.20.

Amplifier 260 is attached to surface 216B in any suitable manner. The conductor 254 of the first power feeding section 250A and the signal input terminal of the amplifier 260 are connected using, for example, a gold wire.

The conductor 244 of the second power feeding section 250B and the ground terminals on the signal input side and the signal output side of the amplifier 260 are similarly connected using a gold wire or the like. The coax is inserted into the hole 228 provided in the projection 226 and the center conductor of the coax is connected in a suitable manner to the signal output terminal of the amplifier 260.

It is possible to form a circuit for driving the amplifier 260 by metallization on the surface 216B of the second portion 216. A terminal portion is provided at the bottom of the amplifier 260, and the terminal portion can be electrically connected to the drive circuit by soldering.

A package for an integrated circuit may be provided on the surface 216B of the second portion 216 integrally with the antenna support 212. Conductors such as the internal conductor of the package, a conductor connecting the internal conductor of the package to a power supply section, a conductor connecting the internal conductor of the package and a coax, or a circuit can be formed by metallization.

Hereinafter, as an example, the principle of a method for manufacturing the antenna of the present invention by molding the antenna support, which is an integral molded product, by injection molding and metallizing it by electroless plating will be explained in Figures 22A to 22A. This will be explained based on Fig. 22C.

An integrally molded product made of a plastic material is manufactured by first performing primary injection molding (as shown in a cross-sectional view in FIG. 22A) using a plastic material, and then chemically roughening the surface of this primary injection molded product 300. A catalyst is applied, and a second injection molding (shown in cross-section in FIG. 22B) is performed with a plastic material so as to cover parts other than the part 302 to be metalized in the next step. The molded product 310 after the second injection molding, which is the antenna support obtained in this way, is
When the metal is then electroless plated, the exposed areas that were not covered with plastic material during the second injection molding (
Plating 312 is done only on the catalyst adhering part) 302, and no plating is done on the second injection molded part (22C
(shown in cross-section in the figure). In this way, metallization is selectively applied to the molded article.

For example, in the antenna support 12'' of an antenna as shown in FIG. 1 after the secondary injection molding before electroless plating is made based on this principle, as shown in FIG. , portions 70'18' are not coated with plastic material from the secondary injection molding and the catalyst is exposed (illustrated by the fish), so they are simultaneously metallized by one electroless plating. As a result, the conductor wire 70 and the power feeding section 18 are integrally metalized.

The plastic material for primary molding suitable for the antenna support of the antenna of the present invention may be any plastic material that can be injection molded and that can be metallized by roughening the surface of the molded product after molding and adding a catalyst. For example, the plastic material for the secondary molding may be any plastic material that can be injection molded and is not metalized after molding, such as polyimide, liquid crystal polymer ABS, polyether sulfone, etc. , polyether sulfone. 1st
The plastic materials for the subsequent and secondary moldings may be of the same type as long as they meet the above conditions. Furthermore, the plastic material is not limited to a single synthetic material, but may also contain various fillers in the form of fibers or powder.

The roughening of the surface of the primary molded product improves the adhesion of the plating and also aims at the integration of the primary molded plastic material and the secondary molded plastic material after the secondary molding. It is done. Surface roughening can be done using various etching solutions such as chromic acid/sulfuric acid, acidic ammonium heptatide/nitric acid,
Hydrochloric acid/nitric acid can be used.

Examples of methods for applying a catalyst required for electroless plating the surface of the primary molded article include a catalyst/accelerator method and a sensitizing/activating method. The former method is a method in which a molded article is immersed in a mixed catalyst solution containing tin and palladium, and then activated with an acid such as hydrochloric acid or sulfuric acid to deposit palladium on the surface of the molded article.

In the latter method, a relatively strong reducing agent such as tin chloride, hypophosphorous acid, or hydrazine chloride is first adsorbed onto the surface of the molded product, and then the molded product is immersed in a catalyst solution containing noble metal ions such as gold or palladium. This is a method in which precious metals are deposited on the surface of the molded product by immersion.

In the electroless plating process, chemical steel plating, chemical nickel plating, and electroless gold plating are usually used.

Effects As explained above, in the antenna of the present invention, since the antenna support body is molded from a plastic material, it can be formed into a three-dimensional shape that matches the characteristics required of the antenna. Since the antenna can have a three-dimensional shape, it is possible to easily design an antenna with high antenna gain and wide-angle directivity. Since the antenna element and the feed section are directly metallized on the antenna support, the antenna element and the feed section do not peel off from the antenna support, and the antenna can withstand use in harsh environments. Since the antenna element and the feeding section including various circuits can be metalized at the same time, complex antenna element shapes and circuits can be easily formed, and variations in the characteristics of the resulting antenna can be reduced. I can do it. Additionally, the antenna assembly process can be greatly simplified and manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the antenna of the present invention, and FIG. 2 is a perspective view of the antenna of the present invention.
Figure 3 is a cross-sectional view of the antenna in Figure 1 modified from the antenna in Figure 1, Figure 4 is a bottom view of the antenna in Figure 3, Figure 5 is balanced-unbalanced conversion. 6 is a sectional view of the antenna in FIG. 5, and FIG. 7 is a perspective view of an antenna in a shape different from that in FIG.
FIGS. 8 and 5 are enlarged sectional views of the antenna of the present invention, FIGS. 11 is a bottom view of the antenna of FIG. 10; FIG. 12 is a perspective view of the antenna of the present invention having a different shape; FIG. 12 is a sectional view of the antenna shown in FIG. 12, FIG. 14 is a sectional view showing a modified version of the antenna shown in FIG. 12, FIG. 15 is a bottom view of the antenna shown in FIG. 14, and FIG. 16 is a sectional view of the antenna shown in FIG. FIG. 17 is a perspective view of the antenna of the present invention having a further different shape; FIG. 18 is a cross-sectional view of the antenna of FIG. 17; FIG. 19 is a cross-sectional view of the antenna of FIG. , FIG. 20 is a bottom view of the antenna in FIG. 19, and FIG. 21 is a cross-sectional view of the antenna in FIG. 19, which is a modified version of the antenna in FIG. 17, in which an amplifier can be incorporated. The bottom view and FIGS. 22A to 22C are cross-sectional views of a molded product in each manufacturing process, showing the principle of an example of the method for manufacturing an antenna of the present invention. FIG. 23 is a perspective view showing the molded product before electroless plating. 1O1lOO1200...Helical antenna, 12.
12A, 12B, 112.212... Antenna support, 16A, 16B, 16c... Antenna element, 18.1
8A, 18B, 18c, 150.250.250A12
50B...Power supply part, 20...Central hole, 22.122.226...Protrusion, 24.42.46A, 46B, 46C, 124, 128
...hole, 30A, 30B, 30B' 30C, 30C'3
2, 32A, 32B, 34A134B, 34C. 36, 42A% 152, 154.244, 246.2
54.256...Conductor, 38A, 38B...Slit 40A, 40A'...Strip conductor, 40B, 40C
...Rectangular conductor, 60.260...Amplifier, 70...Conductor wire, 114...First surface, 116...Second surface, l18.220.242.252...Penetration Hole, 130
．． 230...Patch pattern, 72.140.240
... ground plane, 214 ... first part, 216 ... second part, 218 ... support part, 224 ... space. 300... Molded product after primary molding, - Molded product after secondary molding.

Claims (1)

[Claims] An antenna consisting of an antenna support molded from a plastic material, an antenna element provided on the support, and a feeding section, the antenna element and the feeding section being metallized directly on the support. An antenna featuring: