JPH0194701A - Transmission line - Google Patents

Abstract

PURPOSE:To reduce a slit width and to decrease the leakage of an electromagnetic wave by sandwiching a thin metallic plate with a thin insulator and inserting it into a slit provided on the H surface center of a rectangular waveguide and directed toward a shaft direction. CONSTITUTION:A metallic plate inner conductor 10 is sandwiched with two insulating sheets 11, a sheet 11 is sandwiched and supported by a stand 8 composed of two blocks. The conductor 10 and the sheet 11 are inserted through a slit 2 into a rectangular waveguide 1, and moved in the shaft direction together with the stand 8 along a slit 2. The electromagnetic wave added to an input edge 3 is introduced from the slit 2 through a coaxial line converting connector 9 to the waveguide 1 by the conductor 10. The conductor 10 is protected from the shorting with the slit 2 by the sheet 11 and can be moved. Thus, since the clearance of the side surface of the sheet 11 and the slit 2 can be made smaller, the slit width can be reduced.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a transmission line that can freely change the distance between input and output terminals, has low transmission loss, and has flat frequency characteristics. [Prior Art] Fig. 3 shows a conventional transmission line as shown in, for example, Japanese Patent Application Laid-Open No. 56-47101. In Fig. 1, (1) is a rectangular waveguide;

[2] is a slit placed along the axial direction in the center of the waveguide. (3) is the input end, (4) is the output end, and C5) is the coaxial line, the inner conductor of which is a rectangular waveguide (
1) is inserted into the waveguide through the slit (2). (6) is a non-reflection terminator connected to one end of the waveguide tube. (7) is inserted between the input end (3) and the coaxial line [5] and is a nine-wire array, and electromagnetic waves are transmitted only from the input end to the coaxial line. (8) is the coaxial line (
5) This is a supporting stand for the outer conductor of the coaxial line, and this stand holds the inner conductor of the coaxial line in the slit while keeping the length of insertion into the waveguide constant through the slit (2) of the rectangular waveguide. It allows you to move along. Next, the operation will be explained. The electromagnetic wave applied to the input end (3) is transmitted to the coaxial line 151 through the input terminal (7), passes through the slit (2) of the rectangular waveguide (1), protrudes into the rectangular waveguide, and is transmitted to the coaxial line 151. The line's inner conductor transfers some of that energy into the rectangular waveguide. Electromagnetic waves that are not transmitted from the coaxial line to the rectangular waveguide but are transmitted in the opposite direction along the coaxial line as reflected waves enter the isolator (7).
Its energy is absorbed by Ain V-Yu t'L,
It is not output to the input terminal (3). The nine electromagnetic waves transmitted within the rectangular waveguide travel in both axial directions of the waveguide from the inner conductor of the coaxial line. One goes in the direction of the output end (4) and reaches the output end (4),
The other is absorbed by the non-reflection terminator (6). Non-reflection terminator (6) r! In the absence of this, an unnecessary reflected wave at the other end of the output end (4) of the waveguide will be generated and travel in the direction of the output end (4), directly from the inner conductor of the coaxial line +15) to the output end (4).
) to prevent interference with electromagnetic waves directed towards the earth. The support base (8) for the outer conductor of the coaxial line (5) is connected to the input end (3)
It is possible to move along the slit from the coaxial line [5] to the isolator (7) and further to the inner conductor of the coaxial line, which is inserted completely through the slit [2] into the waveguide. The distance between the input end (3) and the output end (4) of the transmission line #'i obtained by can. [Problems to be solved by the invention] Since the conventional transmission line is constructed as described above, it is necessary to provide a slit with a sufficient width so that the inner conductor of the coaxial line and the slit (2) do not come into contact with each other. However, waveguides for high frequency bands such as millimeter wave bands have small cross-sectional dimensions. There is a problem that the width of the slit cannot be ignored compared to the width of the waveguide, and the leakage of electromagnetic waves from the slit increases. The purpose is to reduce the degree of electromagnetic wave leakage from the @1 slit by narrowing the slit width in the waveguide for the frequency band or higher, thereby obtaining a transparent transmission line. [Means for Solving the Problems] In the transmission line according to the present invention, in place of the inner conductor of the conventional coaxial line, a thin metal plate t is provided with a thin insulator for the purpose of supporting the thin metal plate and insulating it from the slit of the waveguide. Things held between body sheets ft
It is inserted into the waveguide through 2 slin h2. [Function] The thin metal plate inserted into the waveguide in this invention is
The thickness of the part inserted into the waveguide is reduced, and the insulating sheet prevents short circuits due to contact with the slit. Embodiment of the Invention An embodiment of the invention will be described below with reference to the drawings. 1st
In the figure, C1) is a rectangular waveguide, (2) is a friend slit provided in the rectangular waveguide (1), (3) is the input end, and (9) is the input end of the coaxial line of αQ. This is a coaxial line conversion connector that converts to a conductor inside a metal plate. Conductor α in metal plate
Qri is sandwiched between two insulating sheets (11) and supported by a stand (8) consisting of two blocks.Conductor α0 in the metal plate, and the insulating sheet (B) is inserted into the rectangular waveguide (11 through 211 and can be moved in the axial direction of the waveguide along the slit with the stand (8)). Figure 2 shows a stand (8
), which is a cross-sectional view of unit 0 (8), is divided into two blocks on the left and right in Fig. 2, and is supported by sandwiching an insulating sheet, and is also a transmission line constructed with a conductor αq in a metal plate. It serves as an outer conductor. The nine electromagnetic waves applied to the input end (3) pass through the coaxial line conversion connector (9) and are transferred to the metal plate conductor αat holder (8) e
The energy is transmitted through the transmission line which is the outer conductor, and is transmitted into the waveguide through the metal plate conductor αO inserted into the waveguide through nine slits (2) provided in the rectangular waveguide (1). As with the conventional device, the rectangular waveguide (1) has one end serving as an output end, and the other end connected to a non-reflection termination to prevent generation of unnecessary reflected waves. The conductor GO inside the metal plate is lined with an insulating sheet 0υ)
It is possible to reduce the gap between the conductor αq in this friend metal plate and the side surface of the slit (21) and the insulating sheet aυ, which can move in the slit while being protected from short circuits due to contact with t2). The slit width can be reduced by making the thickness of the conductor OI in the metal plate and the insulating sheet 0υ as thin as possible.In the above embodiment, the waveguide is a rectangular waveguide (1). The same effect can be obtained when the waveguide is a single ridge waveguide. In Fig. 4, (2) is a single ridge waveguide with a slit (21 [Effects of the Invention] As described above, according to the present invention, the inner conductor portion inserted into the waveguide through the two slits of the rectangular waveguide is covered with two insulating sheets. Since it is made of sandwiched metal plates, the slit width can be made smaller, thereby reducing the leakage of electromagnetic waves from the slit.
As a device to change. Advantages of using a waveguide as a low-loss transmission line t-<! It can be used in high frequency bands such as the J-wave band.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a transmission line device according to an embodiment of the present invention, FIG. 2 is a sectional view showing conductor support in a metal plate, and FIG.
The figure is a configuration diagram showing another embodiment of the present invention, and FIG. 4 is a configuration diagram of a conventional system. In the figure, (1)... rectangular waveguide, (2)... slit. +3)...Input end, (4)...Output end, (5).
... Coaxial line, (6) ... Reflection-free terminator, (7) ...
・Isolator, (8)...stand* (9)...coaxial line conversion connector, (10...conductor in metal plate, alpha loop...insulating sheet, (2)...single ridge waveguide Pipe, aAI...Ridge 0 Note that the same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Claims] A slit is provided in the center of the H-plane of the rectangular waveguide in the axial direction of the waveguide, and the inner conductor of the coaxial line is converted into a metal plate inner conductor sandwiched between two insulating sheets, and the rectangular waveguide is passed through the slit. By inserting the coaxial line into the wave tube, electromagnetic fields are coupled between the coaxial line and the rectangular waveguide. A transmission line characterized in that the line is an input end, and the distance between the input and output ends can be changed by moving the conductor in the metal plate along the slit.