JPS62269401A - Suspend line - Google Patents

Abstract

PURPOSE:To obtain low loss and excellent frequency characteristic by providing a slit on dielectric substrate at both sides of a strip conductor in the vicinity of said conductor. CONSTITUTION:Since the dielectric substrate adjacent to both sides of the strip conductor 2 does not exist, an electric field produced from the end of a face opposed to the strip conductor 2 in the electric distribution going to an outer conductor from the strip conductor 2 passes through the dielectric substrate only slightly. Thus, the dielectric loss is reduced. The transmission loss of the suspended line is divided into the copper loss by the strip conductor 2 and the dielectric loss by the dielectric substrate 3, the copper loss is increased in proportion to the 1/2 power of the operating frequency and the dielectric loss is increased proportional to the frequency. Thus, the provision of the slit 4 not only decrease the loss of the transmission line but also improves the frequency characteristic.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a suspended line used in the microwave band.

[Conventional technology]

Figure 8 shows, for example, rMicrowave Anyinee.
r's Handbook VoL IJ (ART
This is a cross-sectional view of a conventional suspended line described in P 15N of MCHHOUI Publishing Co., Ltd. In the figure, fi+ is an outer conductor, 121 is a strip conductor, (3) is a dielectric substrate, and (3) is an IJ tube conductor ( 2) are provided in close contact with both surfaces of the dielectric substrate (3).

Next, the operation will be explained. When electromagnetic waves are excited on the suspended line, the strip conductor (2) and the outer conductor I
An electric field distribution (5) as shown in FIG. 4 occurs between l+ and propagates in the axial direction of the strip conductor, so that it operates as a transmission line.

[Problem that the invention seeks to solve]

In the conventional suspended line, the electric field distribution is as shown in FIG. 4. Since a portion of the electric field passes through the inside of the dielectric substrate (31), the electromagnetic wave causes a loss corresponding to the dielectric loss tangent of the a-electric substrate.

This loss increases in proportion to the frequency of the electromagnetic wave, so
There is a problem in that the amount of attenuation that passes through the transmission line becomes large, and the frequency characteristics of the attenuation amount also deteriorates.

The present invention was made to solve these problems, and aims to provide a suspended line having low loss and good frequency characteristics.

[Means for resolving issues]

The suspended line according to the present invention is a suspended line in which slits are provided in the dielectric substrate on both sides of the strip conductor in the vicinity of the IJ tube conductor.

[Effect]

In the VC of this invention, by providing a slit in the dielectric substrate close to the strip conductor, there is no dielectric loss in the electric field distribution that passes through the dielectric substrate, and the loss and frequency characteristics are improved. be able to.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a suspended line, and FIG. 2 is a diagram showing an electric field distribution in the cross section of FIG. 1.

In FIG. 1, Ill is an outer conductor, (2) is a strip line, (31 is a dielectric substrate, and (41 is a slit. The slit (4) is a111 on both sides of the strip conductor (2).
The strip conductor (2) is provided on the body substrate j31 in close proximity to and parallel to the strip conductor (2).

In the suspended line of this invention, the cross section and electric field distribution are as shown in FIG. Since there are no dielectric substrates (3) adjacent to both sides of the strip conductor (21), in the electric field distribution from the strip conductor (2) toward the outer conductor, the electric field generated from the opposite ends of the strip conductor +21 is due to the dielectric Only a small amount of light passes through the substrate, so loss due to dielectric material can be reduced.

The transmission loss of a suspended line is due to the strip conductor (21
Copper loss is divided into copper loss due to a! The loss increases in proportion to the frequency, and by providing b' (and the slit 14), the loss as a transmission line? Not only can it be made smaller, but its frequency characteristics can also be improved.

In the above embodiment, all rectangular slits 14) were provided, but round holes may also be used as shown in FIG.

Furthermore, although the above embodiments have been described with respect to the line section, the same effects as in the above embodiments can be achieved even when used in suspended line type distributors and combiners.

〔Effect of the invention〕

As described above, according to the present invention, by providing a slit in the dielectric substrate close to the strip conductor, the dielectric loss due to the dielectric substrate is reduced, and a suspended line with low loss and good frequency characteristics can be obtained. It has the effect of being

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a suspended line according to an embodiment of the present invention, Fig. 2 is a diagram showing the electric field distribution in a cross section, Fig. 8 is a diagram showing a conventional suspended line, and Fig. 4 is a diagram of the cross section. FIG. 5, a diagram showing the electric field distribution, is a diagram showing another modification. In the figure... is the outer conductor, (2) is the strip conductor, (3
1 is the dielectric substrate, (4) is Surin), and +51 is the electric field distribution. In addition, the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] In a suspended line consisting of a dielectric substrate, an outer conductor provided parallel to the dielectric substrate at a predetermined distance on both sides of the dielectric substrate, and a pair of strip conductors closely attached to both surfaces of the dielectric substrate. , a suspended line characterized in that a slit is provided in a dielectric substrate close to and parallel to a strip conductor.