JPH0529812A - Large power microstrip electric power synthesizer - Google Patents

Abstract

PURPOSE:To realize the miniaturization and the large power of a microstrip type electric power synthesizer and to improve the degradation of reliability caused by heat generation. CONSTITUTION:An external conductor chassis 1 is defined as an earth part. A planer dielectric substance provided on the inside of the external conductor chassis 1 is constituted of a ceramic board 5 for which a grinding work is facilitated and a transmission line conductor 8 formed on the surface of the planer dielectric substance is constituted of a copper plate machined in a required shape. In this case, this synthesizer is constituted by fixing the transmission line conductor 8 to the planer dielectric substance by a screw 9 and fixing the planer dielectric substance to the external conductor chassis 1 by a screw 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a high power microstrip type power combiner used in a frequency band higher than the VHF band.

[0002]

2. Description of the Related Art Conventionally, a coaxial combiner has been proposed as a high power combiner. This coaxial combiner constitutes an impedance transformer by the permittivity between the outer diameter of the inner conductor and the inner diameter of the outer conductor which are coaxially arranged. Since this coaxial type power combiner can select the outer conductor and the inner conductor according to the transmitted power, a large power combiner can be easily produced, and it is generally used as an impedance transformer type (transformer type) combiner. Has been done. However, this is power combining-out is at frequencies VHF40～60MH _Z also and the length of the impedance transformer unit 3m, it is difficult to implement a power combiner in the apparatus. Therefore, in recent years, a microstrip type power combiner that can be easily miniaturized has been put into practical use.

FIG. 3 is a partially exploded perspective view of an example thereof, and FIG. 4 is a sectional view of the assembled state. In this synthesizer, the double-sided copper foil substrate 20 is fixed in the outer conductor chassis 1, the copper foil on one surface of the substrate 20 is photo-etched, and the copper foil on the other surface is used as a grounding portion to form the microstrip line 21.
And a transmission line and an impedance transformer are formed by this line to form a microstrip type power combiner. As a material of the double-sided copper foil substrate 20, a Teflon substrate is generally used because it has a reduced dielectric loss and a stable dielectric constant in the VHF band. The Teflon substrate is made by impregnating glass fiber with Teflon to harden it, and pasting copper foil with a thickness of 30 μm on both the front and back sides.
In addition, 2 is an input terminal, and the inner conductor 4 is connected to the connecting piece 22.
Is connected to the microstrip line.
Reference numeral 14 is a cover.

[0004]

This conventional microstrip power combiner using a copper foil substrate is easy to miniaturize because it is composed of a planar circuit, and the input / output terminals are arranged in a microstrip line. There is an advantage that you can freely choose by drawing around. However, the transmission line made of copper foil is as thin as 30 μm, and the width of the microstrip line becomes wide in order to reduce heat generation due to resistance loss, making it difficult to increase the power when the space forming the planar circuit is limited. There is a problem of becoming. Further, an epoxy adhesive is used to bond the copper foil and the dielectric substrate, but there is a problem that the adhesive strength is deteriorated by heat generation and the reliability is deteriorated. An object of the present invention is to provide a small-sized microstrip type high power combiner capable of increasing the power and improving the reliability.

[0005]

In the high power microstrip type power combiner of the present invention, a plate-shaped dielectric body provided in an outer conductor chassis is formed of a ceramic plate which can be easily cut, and the plate-shaped dielectric body is formed. The transmission line conductor formed on the surface of the body is composed of a copper plate processed into a required shape. Further, it is preferable that the transmission line conductor is fixed to the plate-shaped dielectric body with a screw and the plate-shaped dielectric body is fixed to the outer conductor chassis with a screw to form a synthesizer.

[0006]

According to the present invention, heat can be dissipated by the plate thickness of the copper plate to reduce the temperature rise, and the structure can be realized without using an adhesive, and the power combiner can be made to have a large power.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a partially exploded perspective view of an embodiment of the high power microstrip power combiner of the present invention, and FIG. 2 is a sectional view of the assembled state thereof. The outer conductor chassis 1 formed of a metal material in the shape of a box having an open top constitutes a grounding portion of the microstrip line, and a pair of input terminals 2 is provided on one side surface.
Are arranged side by side, and one output terminal 3 is arranged on the other side surface. An outer conductor of each of these terminals 2 and 3 is connected to the outer conductor chassis 1, and an inner conductor 4 is projected into the outer conductor chassis 1.

A ceramic plate 5 having a thickness of 5 to 10 mm is fixed as a dielectric to the inner bottom surface of the outer conductor chassis 1 with screws 6. For this ceramic plate 5, a machinable ceramic material having excellent machinability and machinability is used. As such a ceramic material, for example, one commercially available under the trade name of "macerite" can be used. The screw 6 is screwed into the outer conductor chassis 1 through an insertion hole 7 formed by cutting the ceramic plate 5.

A transmission line conductor 8 made of a copper plate having a thickness of 2 mm is fixed to the upper surface of the ceramic plate 5 with a screw 9. The screw 9 is a screw hole 10 formed by cutting the ceramic plate 5 through an insertion hole 13 formed in the transmission line conductor 8.
Is screwed onto. The transmission line conductor 8 has the output terminal 3
It is composed of one impedance transformer 11 arranged on the side and a transmission line 12 formed in a bifurcated shape. The impedance transforming portion 11 and the end portions 11a and 12a of the transmission line 12 are folded up in an L shape and connected to the inner conductor 4 of the terminals 2 and 3 by screws (not shown).
14 is a cover.

According to this structure, the microstrip line is composed of the outer conductor shear 1, the transmission line conductor 8 made of a copper plate having a required thickness, and the ceramic plate 5, so that the resistance of the transmission line conductor 8 is increased. It is possible to disperse the heat generated by the loss by the copper plate and reduce the temperature rise of the transmission line conductor 8 by the heat radiation effect of the ceramic plate 5. Further, by using a material having a high withstand voltage and a high dielectric constant for the ceramic plate 5, the ceramic plate 5 can be made thin and the size can be reduced by the wavelength shortening effect. Further, since the ceramic plate 5 is easily cut, screws 6 and 9 are used when fixing the ceramic plate 5 to the outer conductor chassis 1 and when fixing the transmission line conductor 8 on the ceramic plate 5, respectively. A fixed structure can be adopted, and manufacturing and assembling can be easily performed.

[0011]

As described above, according to the present invention, the plate-shaped dielectric is made of a ceramic plate which can be easily cut, and the transmission line conductor is made of a copper plate. And effectively dissipate through the ceramic plate to reduce the temperature rise of the power combiner.
In addition, the high withstand voltage and high dielectric constant of the ceramic plate can be used to make the ceramic plate thin, and the wavelength can be shortened to achieve miniaturization. Furthermore, since the screw is used for assembling the transmission line conductor and the plate-shaped dielectric without using an adhesive,
The reliability does not deteriorate due to temperature.

[Brief description of drawings]

FIG. 1 is a partially exploded perspective view of an embodiment of a power combiner of the present invention.

FIG. 2 is a cross-sectional view of the assembled state of FIG.

FIG. 3 is a partially exploded perspective view of an example of a conventional power combiner.

4 is a cross-sectional view of the assembled state of FIG.

[Explanation of symbols]

1 outer conductor chassis 2 input terminals 3 output terminals 5 Ceramic plate 6 screws 8 Transmission line conductor 9 screws 11 Impedance transformer 12 transmission lines

Claims (2)

[Claims] 1. A microstrip transmission line is composed of an outer conductor chassis, a plate-shaped dielectric fixed in the outer conductor chassis, and a transmission line conductor formed on the surface of the plate-shaped dielectric. In the power combiner, the high-power microstrip power combiner is characterized in that the plate-shaped dielectric is made of a ceramic plate that can be easily cut, and the transmission line conductor is made of a copper plate processed into a required shape. 2. The high power microstrip power combiner according to claim 1, wherein the transmission line conductor is fixed to the plate-shaped dielectric with screws, and the plate-shaped dielectric is fixed to the outer conductor chassis with screws.