JPS5856282B2 - Multi-terminal directional coupler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compact multi-terminal directional coupler having coupling between all input and output terminals.

An example of the structure of a conventional multi-terminal directional coupler using twisted waveguides is shown in FIG.

Further, FIG. 2 is a diagram showing a state of connection in the apparatus of FIG. 1.

1-1 to 1-8 are signal input terminals, 2-1 to 2-8 are signal output terminals, 3-1 to 3-12 are short slot couplers, and 4-1.4-2 is a twisted waveguide. It is.

The input signal from 1-1 is split into two by the coupler 3-1, and each split passes through a twisted waveguide to 3-6 and 3.
It is further divided into two parts by the coupler numbered -8, passed through the twisted waveguide again, and further divided into two parts by the number couplers numbered 3-9 to 3-12. 1 input power each -
is output.

This device is constructed by combining a directional coupler and a twisted waveguide as described above, but the twisted waveguide has a twist angle of 90' with respect to the wavelength in the tube, and the twisted waveguide has a twist angle of about several wavelengths. length is required.

Therefore, the entire device becomes large and heavy, has a complicated structure, tends to have uneven electrical length between input and output, and has the disadvantages that it is difficult to connect with other devices.

Therefore, the present invention aims to improve the above-mentioned drawbacks of the prior art, and its object is to provide a small and lightweight multi-terminal directional coupler.

A feature of the present invention to achieve this object is to connect a plurality of rectangular waveguides in which the tube axes are parallel and eight opposing surfaces are arranged at a predetermined interval, and each of the eight opposing surfaces is coupled. , an E-plane long slot directional coupler with an elongated and wide slot tapered at both ends, and an H-plane long slot directional coupler with the tube axis parallel to the waveguide.
This multi-terminal directional coupler is characterized by having another rectangular waveguide placed close to each other with their surfaces facing each other, and an H-plane directional coupler coupling between opposing H[1ilfi.

Embodiments will be described in detail below with reference to the drawings.

FIG. 3 is an embodiment of an E-plane long slot coupler,
1-Ll-2 is a signal input terminal, 2-1゜2-2 is a signal output terminal, 5-1.5-2 is a rectangular waveguide arranged in parallel, 6 is a coupling slot, , H2D are the length, height, and width of the coupling slot, respectively, and T is the length of the tapered portion of the coupling slot.

As shown in Figure 3, the E-plane long slot coupler is
It has a simple structure in which a coupling slot is simply provided between the parallel E planes of two waveguides, and has the characteristic that good coupling can be achieved even if the width is about the same as the long side of the waveguide.

As for the design method, first decide on the width, then select V, S, W, and R at an appropriate height H.

(Standing wave ratio) and the length L that gives the best directionality are determined.

The degree of bonding can be made variable by changing the height H.

As experimental data, using waveguide WRJ-180, 17
．． In the 0 to 22.0 GHz band, the length of the coupling slot L =
65mm, taper length T=15mm, height H=-1,5
mm, width D = 4. When Omyn, degree of coupling is 3 d
B.

The VSWRl was less than 1 and the directionality was less than 25 dB.

In addition, the coupling slot has the same characteristics in any part of the Effi wall as long as it is parallel to the axis, and even when two waveguides are arranged in parallel with their axes shifted in different stages as shown in Figure 4. Same characteristics.

5A, B, C, D, E, and F are respectively a perspective view of an embodiment of the multi-terminal directional coupler of the present invention, and a sectional view of AA/;
FIG. 6 is a diagram of the bonding state, and is a cross-sectional view along B-B', c-c', D-D', and E-E'. 8 is a signal input terminal, 2-1 to 2-8 are signal output terminals, 5-1 to 5-8 are rectangular waveguides arranged in parallel, and 7-1 to 7-4 are branch couplers (H-plane coupler), 8
-1 to 8-8 are E-plane long slot couplers.

The branch coupler is no different from the conventional one.

The branch couplers 7-1 to 7-4 include waveguides 5-1, 5-2, 5-3, 5-4, 5-5, 5-6° 5-7 and 5, respectively.
-8 and E[1iffi long slot coupler 8
-1 to 8-4 are waveguides 5-1, 5-3, and 5-, respectively.
2 and 5-4. 5-5 and 5-7. waveguides 5-1 and 5-5, 5-2 and 5-6, 5-3 and 5-7, respectively.
, 5-4 and 5-8 are combined.

The reason why twisted waveguides are not needed in the present invention is that while conventional E-plane couplers were only capable of coupling very close waveguides, E-plane long slot couplers 5
This is because, as shown in Figure F, it is possible to couple waveguides that are arranged with a slight deviation.

Next, the operation will be explained.

The input signal incident from 1-1 is split into waveguides 5-1 and 5-2 by branch coupler 7-1, and then split into waveguides by E-plane long slot couplers 8-1 and 8-2. Tubes 5-1, 5-2
, 5-3° and 5-4, and further divided by E-plane long slot couplers 8-5 to 8-8, and the signal output terminal 2
-1 to 2-8.

The same operation occurs when inputting from other input terminals.

FIG. 6 shows the coupling relationship between each waveguide.

It should be noted that as a modification of the present invention, it is possible to create a multi-terminal directional coupler in which rectangular waveguides are coupled only by an Effi long slot directional coupler without using a conventional H-plane directional coupler. Not even.

As explained above, since the present invention is constructed using an E-plane long slot coupler without using a twisted waveguide, the structure is simplified, and the entire device can be made smaller and lighter.
Furthermore, since the surfaces of the input and output terminals are aligned parallel to each other, the electrical lengths between the input and output terminals are all the same, and there is an advantage that connection with other devices is easy.

[Brief explanation of drawings]

FIG. 1 is an example of the structure of a conventional multi-terminal directional coupler, FIG. 2 is a diagram of the connection state of the device shown in FIG. 1, and FIGS. Structure example, 5th
Figure A is a fifth example of the structure of a multi-terminal directional coupler according to the present invention.
Figure B, Figure 5 C1, Figure 5 D, Figure 5 E, and Figure 5 F are cross-sectional views of various parts of the device in Figure 5 A, and Figure 6 is a diagram of the combined state of the device in Figure 5 A. . 1-1, 1-2, 1-3, 1-4, 1-5,
1-6, 1-7, 1-8...signal input terminal, 2-1゜2-2, 2-3, 2-4, 2-5,
2-6, 2-7.2-8...Signal output terminal,
3-1, 3-2゜3-3, 3-4, 3-5, 3-
6, 3-7, 3-8, 3-9, 3-10, 3
-11, 3-12...Short slot coupler, 4-1.4-2...Twisted waveguide, 5-1
, 5-2 , 5-3 , 5-4 . 5-5, 5-6, 5-7, 5-8... Rectangular waveguide, 6... Coupling slot, L...
・Length of the coupling slot, H... Height of the coupling slot, D... Width of the coupling slot, T...
・Length of tapered part of coupling slot, 7-1, 7-2
, 7-3, 7-4...branch coupler, 8-1
, 8-2 , 8-3 , 8-4 , 8-5 , 8-6
．． 8-7.8-8...E [i long slot coupler.

Claims (1)

[Claims] 1 A plurality of rectangular waveguides arranged at a predetermined interval with their tube axes parallel and eight opposing sides, and a long and wide slot tapered at both ends that connects each of the eight opposing sides. an E-plane long slot directional coupler having an E-plane long slot directional coupler, another rectangular waveguide arranged in close proximity to the waveguide with its tube axis parallel to the waveguide and its H-planes facing each other, and an H-plane coupling between the opposing H-planes. A multi-terminal directional coupler, characterized in that it has a directional coupler.