JPH0522006A - T-branched waveguide - Google Patents

Abstract

PURPOSE:To match an impedance from the input terminal side of the main waveguide of the T-branched waveguide over a wide band, to reduce a power loss as well and to facilitate the manufacture. CONSTITUTION:This T-branched waveguide is composed of a main waveguide 16 and a branched waveguide 20, which cross section is rectangular, coupled to one H plane of this main waveguide 16. This T-branched waveguide is equipped with a conductor plate 26 contacting the wide plane to the E plane of a coupled part between the main waveguide 16 and the branched waveguide 20 and contacting one plane to the H plane opposite to the H plane of this coupled part so as to match the impedance from the side of an input terminal 12 of the main waveguide 16. By adjusting the width, length and thickness of this conductor plate 26, the impedance from the input terminal 12 of the main waveguide 16 is matched over the wide band.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a T-branch waveguide used for power distribution and combination in the microwave and millimeter wave bands.

[0002]

2. Description of the Related Art A T-branch waveguide in which one end of the main waveguide is an input end and a branch waveguide is coupled to the H-plane is used for impedance matching from the input terminal side of one end of the main waveguide. Various means have been implemented and some of these means are shown in FIGS.

The T-branch waveguide shown in FIG. 3 has a conductive metal post 22 perpendicular to the E-plane of the main waveguide near the coupling portion between the main waveguide 16 and the branch waveguide 20. The impedance from the input terminal 12 side, which is one end of 16, was matched by adjusting the diameter, length and position of the conductive metal post 22.

The T-branch waveguide of FIG. 4 has the branch waveguide 20 at the joint surface between the main waveguide 16 and the branch waveguide 20 in addition to the conductive metal post 22 of the T-branch waveguide of FIG. Has a window 24 having a cross section smaller than the cross section, and the window 24 allows impedance matching in a wide band.

[0005]

However, among the T-branch waveguides of the prior art, the T-branch waveguide of FIG. 3 acts only on a part of the coupling portion where the electric field is concentrated for impedance matching. Therefore, the impedance from the input terminal side is
There is a drawback that impedance matching is performed only in a narrow band. In addition, the T-branch waveguide of FIG. 4 can match the impedance from the input terminal side in a wide band, but it is difficult to manufacture because the T-branch waveguide has a window on the joint surface. There is a drawback that the distributed power is reduced to about -10 dB.

An object of the present invention is to avoid the above-mentioned drawbacks, to match the impedance from the input terminal side at one end of the main waveguide in a wide band, and to easily manufacture the T-branch conductor. To provide a wave tube.

[0007]

In order to solve the above problems, the present invention provides a main waveguide of rectangular cross section having one end as an input terminal and the other end as a first output terminal, and a main waveguide of the main waveguide. In a T-branch waveguide, which is composed of a branch waveguide having a rectangular cross-section coupled to one of the H-planes and whose end portion is the second output terminal, the input terminal side of the main waveguide In order to match the impedance from, the wide surface is in contact with the E surface of the coupling portion of the main waveguide and the branch waveguide, and one surface is in contact with the H surface of the coupling portion opposite to the H surface. It is to provide a T-branch waveguide characterized by the above.

[0008]

As described above, in order to match the impedance from the input terminal side of the main waveguide, the wide surface comes into contact with the E surface of the coupling portion between the main waveguide and the branch waveguide, and the H surface of this coupling portion. If a conductor plate whose one surface is in contact with the H surface on the opposite side is used, the impedance from the input terminal of the main waveguide can be matched in a wide band by adjusting the width, length and thickness of this conductor plate. it can. Further, the conductive plate acts on the electromagnetic field over a wide coupling portion between the main waveguide and the branch waveguide, and the electric power is effectively distributed to the branch waveguide.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of the present invention will be described in detail. FIG. 1 shows a T-branch waveguide 10 according to the present invention. And a main waveguide 16 having a rectangular cross section with the other end having the first output terminal 14
And a branch waveguide 20 having a rectangular cross section that is coupled to one H surface of the main waveguide 16.
Is used as the second output terminal 18.

The T-branch waveguide 10 of the present invention is a main waveguide 1.
In order to perform impedance matching from the side of the input terminal 12 of 6, the wide surface comes into contact with the E surface of the coupling portion of the main waveguide 16 and the branch waveguide 20, and the H surface of the coupling portion is opposite to the H surface. A conductor plate 26 is in contact with one surface. This conductor plate 26
May be integrally formed with the main waveguide 16 and the branch waveguide 20, or may be formed separately from these waveguides and fixed with screws or a conductive adhesive.

The width, length and thickness of the conductor plate 26 are adjusted so that impedance matching from the input terminal 12 side is performed in a wide band. In addition, the conductor plate 26
Acts on the electromagnetic field over a wide coupling portion between the main waveguide 16 and the branch waveguide 20, so that impedance matching can be performed in a wide band. FIG. 5 shows the results of the frequency characteristics of the T-branch waveguide 10 of the present invention shown in FIG. 1 and the T-branch waveguide of the prior art shown in the figure as seen from the input terminal. The solid line shows the frequency characteristics of the present invention. The broken line shows the frequency characteristic of the prior art. From FIG. 5, it is understood that the T-branch waveguide of the present invention can perform impedance matching in a wider band than the T-branch waveguide of the prior art. At this time, in the T-branch waveguide 10 of the present invention, the power distribution to the output terminal 14 of the main waveguide 16 and the output terminal 18 of the branch waveguide 20 is about 6: 4, and the distribution of the power of the branch waveguide 20 is about 6. Electric power can be sufficiently output to the output terminal 18.

FIG. 2 shows another embodiment of the present invention, except that in this embodiment the conductor plate 26 has tapers 26a at both ends that reduce in thickness toward the E-plane of the main waveguide 16. It is substantially the same as the T-branch waveguide 10 of FIG. This is preferable because impedance matching from the input terminal 12 is performed in a wider band.

[0013]

According to the present invention, as described above, in order to match the impedance from the input terminal side of the main waveguide, the E-plane of the coupling portion between the main waveguide and the branch waveguide has a wide surface. Of the main waveguide is used in a wide band by adjusting the width, length and thickness of the conductor plate. The impedance from the terminals can be matched, and the conductive plate acts on the electromagnetic field over the wide coupling portion between the main waveguide and the branch waveguide, and the power is effectively distributed to the branch waveguide as well. is there.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a T-branch waveguide according to the present invention.

FIG. 2 is a perspective view of another embodiment of the T-branch waveguide according to the present invention.

FIG. 3 is a perspective view of one example of a prior art T-branch waveguide.

FIG. 4 is a perspective view of another example of a prior art T-branch waveguide.

5 is a diagram showing frequency characteristics of the T-branch waveguide shown in FIGS. 1 and 4. FIG.

[Explanation of symbols]

 10 T branch waveguide 12 input terminal 14 output terminal 16 main waveguide 18 output terminal 20 branch waveguide 26 conductor plate

Claims (1)

Claim: What is claimed is: 1. A main waveguide having a rectangular cross section having one end as an input terminal and the other end as a first output terminal, and a rectangular cross section coupled to one H surface of the main waveguide. And a branch waveguide of
In a T-branch waveguide having an end of the branch waveguide as a second output terminal, the main waveguide and the branch waveguide are coupled so as to perform impedance matching from the input of the main waveguide. A T-branch waveguide comprising a conductor plate having a wide surface in contact with an E surface of the portion and one surface in contact with an H surface of the coupling portion opposite to the H surface.