JPS59191901A - Microwave circuit - Google Patents

Abstract

PURPOSE:To ensure the stable shielding performance by giving individual shielding to each microstrip circuit. CONSTITUTION:The electric shielding is given to a dielectric substrate 2 containing a microstrip MIC circuit with a shielding material 21. This shielding has holes 22 and 23 so that the MIC circuit can be controlled after shielding. This shielded MIC circuit is attached on an earth conductor 3 of another dielectric substrate 1 containing another MIC circuit. These two MIC circuits of both substrates 1 and 2 are electrically connected to each other with a connection pin 13. The substrate 1 is packaged into a chassis 14 and receives the electric shielding with addition of a cover 16. Thus the MIC circuit which has easily characteristic variation is partially shielded by itself. Therefore the characteristic difference is reduced between package of all circuits and that of a single unit of circuit. Thus, the stable MIC circuit is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a microwave circuit using a dielectric substrate, and particularly to a microwave circuit that has a high high frequency shielding effect and can easily attach dielectric substrates to each other.

[Background of the invention]

An example of a conventional microwave circuit shield structure using a dielectric substrate is shown in FIGS. 1 and 2.

FIG. 1 shows a cross-sectional view of a structure in which two microwave circuits each consisting of a microstrip line constructed using a dielectric substrate are mounted in a housing.

In the figure, 1 is a dielectric substrate, 2 is a dielectric substrate, 6 is a ground conductor, 4, 5, 6, 7.8 and 9 are microstrip lines, 10.12 is a microstrip line, 1
1 is a grounding conductor, 13 is a connection bin, 14 is a chassis, 15.
16 is a cover.

Further, FIG. 2 is a plan view taken along the line AA' in FIG. 1. 17 is a connection pin, and 18 and 19 are microstrip lines.

A circuit is configured with microstrip lines on dielectric substrate 1, and a circuit is configured with microstrip lines on dielectric substrate 2, and the back ground conductors 11 and 12 of both substrates are attached so as to be in contact with each other, and signals are input and Connect the output part via the bins 13 and 17 and connect the metal chassis 1
4 shows a shielding structure of a microwave circuit which is electrically connected to 1 and mechanically connected to 1 and shielded by covers 15 and 16. In the figure, if the dielectric constants of dielectric substrates 1 and 2 are not sufficiently high or the thickness of the plates is thick, the degree of concentration of the electric field between the ground conductor of each substrate and the microstrip line pattern decreases, and the radiation increases. 15 and 16
If the distance between each substrate changes by 1.20 mm, the characteristics will change. Furthermore, the characteristics obtained with each substrate alone may not match the characteristics obtained with shielding and fC as shown in FIG. In this way, the characteristics of the shield structure shown in the example tend to change easily, and the design is difficult.

[Purpose of the invention]

An object of the present invention is to provide a microwave circuit consisting of a microstrip line using a dielectric substrate, which has a shield structure that is difficult to change in characteristics and is easy to design. be.

[Summary of the invention]

In the present invention, in a microwave circuit consisting of a microstrip line using a dielectric substrate, a microwave circuit whose characteristics tend to change easily due to changes in the surrounding geometric shape, etc. is partially shielded, and the characteristics obtained by itself can be obtained by partially shielding the microwave circuit. The difference in characteristics obtained when this is implemented is reduced.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 6 to 5.

FIG. 6 is a plan view of the shielded microwave circuit board configured on the dielectric substrate 2 in FIG. This is a hole made for this purpose.

FIG. 4 is a cross-sectional view taken along the line BB' in FIG. 3, and parts having the same functions as those in FIGS. 1 to 6 are given the same numbers, and their explanations will be omitted. The shield body 21 is electrically and mechanically connected to the ground conductor 11 of the substrate 2, and is connected to the microstrip line 19.
17 is electrically shielded.

FIG. 5 shows a structure in which a structure shielded with a shield body 21 as shown in FIGS. 6 and 4 is attached to another board 1, mounted on a chassis 14, and a cover 15, 16 is attached. 2 shows a cross-sectional view corresponding to FIG. 1 in the case of FIG.

〔Effect of the invention〕

According to the present invention, it is possible to stably shield a microwave circuit, and the influence of changes in the surrounding geometric shape is sufficiently reduced, which is effective in terms of characteristic management and design freedom.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the shielding structure of a conventional microwave circuit consisting of a circuit board made up of two microstrip lines, the second is a plan view, and the third is a shielded structure of the microwave board individually. FIG. 4 is a plan view showing an embodiment of the present invention, FIG. 4 is a cross-sectional view of FIG. 6, and FIG. 5 is a cross-sectional view when the board according to the embodiment of the present invention is mounted. 1.2...Dielectric substrate 311...Ground conductor 14...Chassis 1516... Kanoku -21・・・・・・
-... Shield body Figure 1 Figure 3 Figure 22 Figure 4 Figure 5 Procedural amendment (method) Indication of case Patent application No. 65598 of 1982 Name of invention Microwave circuit amendment person 11e1 i order Patent applicant name '5101 p Formula /:
Written by Tate Koashi Kawaguchi Representative: 〒1 (Xl Hitachi Ltd. Shiso Works, 5-1 Marunouchi, Chiyoda-ku, Tokyo Telephone: J
! 1・212-1111 (Input) 2) Subject of amendment Contents of amendment in the brief explanation of drawings section of the specification Section 5 of the specification
Correct "2nd" in the 11th line of the page to "Figure 2".

Claims (1)

[Claims] 1) In a microwave circuit comprising a first dielectric substrate on which a circuit consisting of a microstrip line υ is formed, and a second dielectric substrate on which a circuit consisting of a microstrip line υ is also formed, the first A microwave circuit characterized in that the dielectric substrate is shielded from high frequencies and then attached to the second dielectric substrate, and the whole is further shielded from high frequencies.