JPS58119204A - Waveguide coupling device - Google Patents

Abstract

PURPOSE:To attain excellent directive coupling over a wide band, by combining an E plane bent waveguide connected to a narrow waveguide wall of a waveguide and an H plane bent waveguide connected to a wider waveguide wall, as a branching waveguide connecting the parallel waveguide. CONSTITUTION:A main waveguide 1 having terminalsI, II and a subwaveguide 2 having terminals III, IV are placed in parallel by opposing broad planes and the waveguides are connected with branching waveguides 4, 5 having about 1/4 or 3/4 guide wavelength. The waveguide 4 is an E-plane bent waveguide and connected to the narrow guide wall of the waveguidesI, II, and te waveguide 5 is an H-plane bent waveguide and connected to a broader waveguide wall. Waves incident from the terminalIand coupled via the waveguide 4 are outputted to terminals III, IV as the electric fields in the same direction. On the other hand, waves coupled with the waveguide 5 are outputted to the terminals III, IV as the electric fields in the opposite direction. The waves at the terminal III are cancelled and the coupled waves are outputted only at the terminal IV. Thus, excellent directional coupling is attained over a wide band.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a 4tf
This article, which concerns improvement of the L-tube coupler, will be explained assuming that the design center frequency of the waveguide coupler is fo.

First, the conventional waveguide type coupler shown in FIG. 1 will be briefly explained.

In Figure 1, (1) is the main waveguide, (2) is the sub-waveguide, (3) is the branch waveguide, ■ and ■ are the terminals of the main waveguide (1), and ■ and W are the sub-waveguides. This is the terminal of the wave tube (2).

The main waveguide (1) and the sub-waveguide (2) are placed in parallel with their wide surfaces facing each other, and are connected by a branching pipe tLf t3) having a length of about % of the wavelength in the pipe at one frequency 10. The branch waveguide (3) has main and open fields ti, f(1), (2)
The main waveguide (1) (
2) There are many arrays in the longitudinal direction.

Next, the operation of the waveguide type coupler is, for example, mainly 4t.
Frequency/of input from terminal ■ of L tube (1).

waves are coupled to the sub-waveguide (2) via the branch waveguide (3). At this time, since the single-branch waveguides (3) are arranged at a pitch interval of approximately % of the internal wavelength of the frequency t31A, this waveguide type coupler has a function as a directional coupler, and the sub-guide The wave coupled to the wave tube (2) comes out at terminal W.

In addition, a branch waveguide (3
), a large amount of coupling can be obtained even with a small number of branched waveguides (3), and the tube axis length is shorter than that of the porous type.

However, in this waveguide type coupler, the pitch interval of the branch JFF tube (3) deviates from the wavelength within the tube at frequencies other than e10, so the directivity deteriorates. For this reason, there was a drawback that the directional frequency characteristic was a narrow band.

This invention aims to eliminate such drawbacks.

A combination of an E white waveguide and an H white waveguide is used as a branch waveguide, and the drawings will be described in detail below.

FIG. 2 shows one embodiment of this invention, (1).

(21, I~y are the same as in Figure 1, C4)e (5
) is a branch waveguide. Figure (a) is a perspective view, figure (b)
) is a side view, and (C) is a front view.

The branch waveguides (4) and (5) are B multi-polar waveguides and H multi-polar waveguides, and the length of the center line is selected to be about or about % of the wavelength in the pipe at frequency j. ing.

In the waveguide type coupling of the present invention, the characteristics of a directional coupler are obtained by utilizing the difference in coupling characteristics between the single branch waveguide (4) and the branch waveguide (5). The waves that are incident from the terminal ■ of the main waveguide (1) and coupled through the nine-branch waveguide (4) come out from the terminals 'rx and wK with an electric field in the same direction. On the other hand, the waves coupled via the branch waveguide (5) emerge at the terminals m and F/ with an electric field in the opposite direction.

Therefore, if the single-branch waveguide (4) and the branch waveguide (5) are designed to have the same amount of coupling, the waves coming out to the terminal I will be canceled out, and the waves coupled only to the ys child W will come out. come.

In this way, this waveguide coupler has a function as a directional coupler.

The waveguide type coupler of this invention has two branched four-way tubes (four branches).
) and (5) are provided at the same position in the tube axis direction of the main and sub-waveguides +1) and (2), so the directivity does not deteriorate even at frequencies other than +10.

In addition, since the nine-branch waveguides (4) and (5) have a length of about or about % of the wavelength in the tube, a large amount of coupling can be obtained with a short tube axis length, similar to the conventional waveguide type coupler. be able to.

Although the main and sub-waveguides have been described as rectangular waveguides in the above description, the present invention is not limited thereto, and may be used in the case of a circular four-waveguide or a semicircular waveguide.

As described above, in the waveguide type coupler according to the present invention, by using two ridge waveguides combined in a T-shape as a single-branch waveguide, good directivity can be obtained over a wide band. It has the advantage of being able to

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional waveguide coupler. FIG. 2 is a schematic configuration diagram showing an embodiment of a waveguide coupler according to the present invention. In the figure, (b) is a side view and (C) is a front view, (l) is the main waveguide, (2) is the sub waveguide, (3)
, (4) and (5) are branch waveguides. In FIG. 1, the same or corresponding parts are designated by the same reference numerals. 2nd (b) (C)

Claims (1)

[Claims] In a branch waveguide type coupler in which two parallel waveguides are connected by a branch waveguide of about % or about % of the wavelength in the tube, the narrower one of the parallel waveguides is used as the branch waveguide. A waveguide characterized by using a combination of an E white waveguide connected to the tube wall of the parallel waveguide and an H white waveguide connected to the wider tube wall of the parallel waveguides. Tubular coupler.