JPS62149201A - Both side metal clad dielectric base for plane antenna - Google Patents

Abstract

PURPOSE:To improve the high frequency characteristic and heat-resistance and to reduce the material and processing cost by using the entire rear face of the titled dielectric base plate as a ground conductor and including a polymethylpentene resin to the dielectric layer. CONSTITUTION:The entire rear face of the dielectric base plate is used as a ground conductor, a circularly polarized wave radiation microstrip element realized by a metallic foil is provided on the surface and a polymethylpentene resin is included for the dielectric layer. The dielectric base plate, in this case, is formed incorporatedly by the combination of a glass cloth, a fluororesin film or a fluororesin-glass composite member is addition to the poly methylpentene resin film or sheet, the lamination and heating/pressing of them. It is preferred to apply corona discharge processing to the film or sheet, in this case, in order to improve the adhesive strength between the polymethylpentene resin and fluororesin film or sheet and the metal or between the resin films or the sheets. Through the constitution above, the high frequency characteristic and the heat resistance are improved and the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a double-sided metal-clad dielectric substrate for a planar antenna with extremely low dielectric loss.

<Prior Art> Planar antennas are being developed for satellite broadcast reception, and are characterized by being less affected by snow accumulation and wind pressure than parabolic antennas. However, at present, it is used with the problem that the gain is slightly low. Such dielectric materials are expensive and have large dielectric losses, and require improvement.

<Objective of the Invention> The present invention has been made based on the discovery that excellent high frequency characteristics, which could not be obtained with conventional dielectric substrates for planar antennas, can be obtained by using polymethylpentene resin, and after conducting various studies, the present invention has been developed. This is what we have come to complete.

<Structure of the Invention> In the present invention, the entire back surface of a dielectric substrate is used as a ground conductor, and a metal foil for forming a circularly polarized radiation microstrip element is provided on the surface, and the dielectric layer is made of polymethylpentene resin. A double-sided metal-clad dielectric substrate for a planar antenna, comprising:

The polymethylpentene used in the present invention is TPXX-22 manufactured by Mitsui Petrochemical Industries.

The above-mentioned TPX■ has a melting point of 240° C. and a dielectric constant of 2.1, and has excellent characteristics as a dielectric material for a planar antenna.

The laminated structure and manufacturing method of a dielectric substrate for a planar antenna will be briefly described. A double-sided metal-clad dielectric substrate for a planar antenna can be made by inserting a 1.0 to 2.0 mm thick plate and integrally molding it using an electric press at a heating platen temperature of 300° C. and a pressure of 40 kg//cd.

It is preferable that the surface of the aluminum plate be roughened by anodizing treatment, physical polishing treatment, etc. to improve adhesion to polymethylpentene resin. Further, as the copper foil, electrolytic copper foil, rolled copper foil, and oxygen-free copper foil can be used, but oxygen-free copper foil is preferable from the point of view of high frequency characteristics of anti-depression. As the dielectric material, in addition to polymethylpentene resin film or sheet, glass cloth, fluororesin (Teflon ■, etc.) film, fluororesin-glass cloth composite material, etc. are combined and laminated and integrated by heating and pressure. Can be molded.

In this case, in order to improve the adhesion between the polymethylpentene resin or fluororesin film or sheet and the metal, or between the resin films or sheets, it is preferable to subject the film or sheet to a corona discharge treatment.

<Effects of the Invention> According to the present invention, it is possible to obtain a double-sided metal-clad dielectric substrate for a planar antenna that is excellent in terms of high frequency characteristics, heat resistance, raw material cost, and processing cost.

Therefore, as part of the future satellite broadcasting reception system,
This will make a major contribution to its spread.

Embodiments The double-sided metal-clad dielectric substrate for a planar antenna according to the present invention will be described below with reference to Examples and Comparative Examples.

Example-1 35pm NML copper-deposited foil/800μm thick TPX film/2. Ommm thick layered aluminum plates were laminated in this order and heated and pressed at a heating platen temperature of 300° C. and a pressure of 40 kg/7 to integrally mold them.

Example-2 35 μm thick oxygen-free steel foil / 800 μm thick TPX film / 2.0 mm thick aluminum plate were laminated in this order,
The plate was heated and pressed at a temperature of 300° C. and a pressure of 40 kg/4 to form an integral mold.

Example-3 35 μm thick oxygen-free steel foil 150 μm thick Teflon film / 800 μm thick TPX film / 2.0 mm
Layer thick aluminum plates in this order and heat platen temperature to 350°.
It was integrally molded by heating and pressing at a C pressure of 40 g/c and 1.

Example-4 35 μm thick electrolytic copper electrolytic 50 μm thick Teflon film/
200μm thick Teflon glass cloth prepreg/6
ooμm thickness TPX■ film/2. Laminate the aluminum plates in this order and heat the plate at a temperature of 350°C and a pressure of 40°C.
It was integrally molded by heating and pressing at a pressure of 1 kg/kg.

Example-5 vμμm thick plain steel copper foil/thickness 200μm 'rpx ■ film/thickness 100/1m glass cloth/thickness 500μ
mTPX film/thickness 2.0 mm Aluminum plates were laminated in this order, heating plate temperature 300°C, pressure 40
kg/'', and was integrally molded by heating and pressing.

Example-6 35μm thick oxygen-free steel foil/thickness 200μm 'rpx ■ film/thickness 100μm glass cloth/thickness 500μm
TPX ■ Film / 35 μm thick oxygen-free copper foil / 50 μm thick
m Epoxy resin rigid film/2. Ommm thick layered aluminum plates were laminated in this order and integrally formed by heating and pressing at a heating platen temperature of 300'C and a pressure of 40g/cm.

Comparative Example-1 35 μm thick electrolytic copper electrolytic copper foil 0 μm thick crosslinked polyethylene sheet/2. Omm thick aluminum plates were laminated in this order, heating plate temperature 350°C, press pressure 40 kg/, (
It was heated and pressurized and molded into one piece.

Comparative Example-2 35 μm thick electrolytic copper electrolytic 50 μm thick Teflon film/
200μm thick Teflon・Glass cloth prepreg 4
A 150 μm thick Teflon film/2.0 mm mm sheet was laminated in this order and integrally formed by heating and pressing at a heating platen temperature of 350° C. and a press pressure of 40 kg/cd.

The materials used in the Examples and Comparative Examples will be explained below.

TPX■: Manufactured by Mitsui Petrochemical Industries■ TPX■X-442
, 0mm thick aluminum plate: The adhesive surface is anodized,
We aimed to improve adhesive strength.

Oxygen-free copper foil: Hitachi Cable ■ OFC foil Teflon ■ film: Mitsui 70 Rochemical ■ PFA film Teflon/glass cloth prepreg: Toppan Printing ■ Chemfaap ■ T, C, G, F No. 1008 Epoxy resin adhesive film: (Manufactured by Bunshishi ■) / Isol 0X-072F cross-linked polyethylene sheet: Noridur Jano-kun's Noridur ■ TPX ■ and Teflon ■ films were used after improving their wettability by corona discharge treatment.

In order to evaluate the characteristics of the double-sided metal-clad dielectric substrates obtained in Examples 1 to 6 and Comparative Examples 1 and 2, a strip line was formed by etching the copper foil surface, and a strip line was formed at a frequency of 12 GHz.
The dielectric constant (6) and dielectric loss tangent (tan δ゛) at (=12×100 Hz) were measured. The results are shown in Table-1.

As can be seen from Table 1, the double-sided metal-clad dielectric substrates obtained in Examples 1 to 6 are not only less expensive than conventional products, but also have a lower dielectric constant and a lower dielectric loss tangent. Yes, it is an excellent material for planar antennas.

In addition, regarding the differences between electrolytic copper foil and oxygen-free copper foil, Table 1
Although it is not clear, as a result of evaluating the gain as an actual planar antenna, the oxygen-free copper foil was 1 dB better, and its effect became clear.

In addition, by using the configuration of Example-6, Example-5
The gain was as high as 0.5 dB because radio waves could be radiated from the oxygen-free copper foil surface, which had a relatively smooth surface, rather than from the roughened aluminum plate.

Claims (2)

[Claims] (1) The entire back surface of the dielectric substrate is a ground conductor, and the surface is provided with metal foil for forming a circularly polarized radiation microstrip element, and the dielectric layer contains polymethylpentene resin. Double-sided metal-clad dielectric substrate for planar antennas. (2) The double-sided metal-clad dielectric substrate according to claim (1), wherein the surface of the dielectric substrate is an oxygen-free copper foil.