JP2009260878A - T-branch waveguide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a T-branch waveguide used as a power splitter or a synthesizer, which can attain impedance matching in a wide frequency band. <P>SOLUTION: The T-branch waveguide 9 includes a first waveguide 1 having an input-output port 5 at one end and a connection port 4 at the other end; and a second waveguide 2 having a first input-output port 6 at one end, a second input-output port 7 at the other end, and a connection port 3 at one side surface. The waveguide 9 is used as a splitter or a synthesizer in which the connection port of the first waveguide is connected to the connection port of the second waveguide. At the connection part of the connection port of the first waveguide and the connection port of the second waveguide, there is provided a frame-shaped matching projection 8 which projects inside traversing from the first waveguide to the second waveguide throughout the entire periphery of the tube of the first waveguide. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a T-branch waveguide used for power distribution and synthesis in the microwave and millimeter wave bands.

  Conventionally, one end of the main waveguide (T-shaped vertical bar portion) is used as an input terminal, and the other end is joined to the E-plane (one side surface) of the branching waveguide (T-shaped horizontal bar portion). In a T-branch waveguide having two ends of the tube (both ends of the horizontal bar) as output terminals, impedance matching from the input terminal side of the main waveguide is performed. Impedance from the input terminal side, which is one end of the main waveguide, having an iris that acts as an inductive susceptance perpendicular to the H-plane of the main waveguide at a position moved to the main waveguide side by a suitable distance from the junction In some cases, impedance matching is performed by adjusting the width, length and position of the conductive iris (for example, see Non-Patent Document 1 below).

  Further, as another conventional matching method, there is a method of loading a circular post in a branch waveguide of a main waveguide and a branch waveguide (for example, see Non-Patent Document 2 below).

Fumiichi Oguchi, “Microwave and Millimeter Wave Circuit”, Maruzen Co., Ltd., 1966, p.165 Mitsuyoshi Kishihara et al., “Analysis of Waveguide E-plane Discontinuity Based on Planar Circuit Method”, IEICE Transactions (C), Vol. J83-C, No. 1, pp. 45-52, 2000 January

  However, in the above-described conventional method, since matching is performed by providing a matching element at a position on the main waveguide side away from the junction between the main waveguide and the branch waveguide, the frequency shifts. Since the phase is shifted by the distance, there is a problem that impedance matching cannot be performed in a wide band.

  The present invention has been made to solve the above-described problems. For example, a T-branch waveguide capable of matching the impedance from the input terminal side of the main waveguide in a wide band. An object of the present invention is to provide a T-branch waveguide used as a power distributor or synthesizer capable of impedance matching in a frequency band.

  The present invention has a first waveguide having one end as an input / output terminal and the other end as a connection terminal, one end as a first input / output terminal, and the other end as a second input / output terminal. A T-branch waveguide used as a distributor or synthesizer in which the connection terminal of the first waveguide and the connection port of the second waveguide are connected to each other. The second waveguide is connected to the connection portion between the connection terminal of the first waveguide and the connection port of the second waveguide over the entire circumference of the tube of the first waveguide and from the first waveguide. A T-branch waveguide is characterized by having a frame-like alignment protrusion protruding inward across the wave tube.

  The present invention can provide a T-branch waveguide used as a power distributor or synthesizer capable of impedance matching in a wide frequency band.

The T-branch waveguide according to the present invention can be used as a distributor or a synthesizer by switching the input / output direction. Hereinafter, a case where the T-branch waveguide is applied as a distributor will be described.
Embodiment 1 FIG.
FIG. 1 is a perspective view showing a configuration of a T-branch waveguide according to Embodiment 1 of the present invention, and FIG. 2 is an AA line of the T-branch waveguide of FIG. FIG. 1 and 2, reference numeral 1 denotes a main waveguide having a pair of wide surfaces and a pair of narrow surfaces and having a rectangular cross section orthogonal to the longitudinal direction, and 2 similarly includes a pair of wide surfaces and a pair of narrow surfaces. Branch waveguide having a rectangular cross section perpendicular to the longitudinal direction, 3 is a connection port provided on one wide surface (E surface) of the branch waveguide 2, and 4 is one end of the main waveguide 1. The connection terminal 3 is connected to the connection port 3 provided in the branch waveguide 2, and the connection terminal 4 of the main waveguide 1 and the connection port 3 of the branch waveguide 2 are connected to each other. A wave tube 9 is formed.

  The main waveguide 1 is provided with an input terminal 5 at the end opposite to the connection terminal 4. The branch waveguide 2 has a first output terminal 6 at one end and the other end. A second output terminal 7 is provided. Reference numeral 8 denotes a connecting portion (connecting port 3 and connecting terminal 4) between the main waveguide 1 and the branching waveguide 2 that protrudes toward the inside of the tube and narrows the branching waveguide 2 from a part of the main waveguide 1. This is a frame-shaped alignment protrusion formed over the entire circumference of the pipe of the main waveguide 1 so as to extend over a part (the whole circumference in a plane perpendicular to the longitudinal direction). Provided on the wide surface of the wave tube 2 and on the first output terminal 6 side, on the wide surface of the first projection 8a, the main waveguide 1 and the branch waveguide 2 and on the second output terminal 7 side. The second protrusion 8b and the third protrusions 8c on both sides provided on the narrow surface side of the main waveguide 1 are formed.

  Next, the operation will be described. The millimeter wave or microwave band RF signal input from the input terminal 5 is distributed to the first output terminal 6 and the second output terminal 7 and output. Here, in the T-branch waveguide 9 shown in FIGS. 1 and 2, the length of the alignment protrusion 8 extending toward the main waveguide 1 and the protruding height (along the tube longitudinal direction of the main waveguide 1). By adjusting the length extending to the branching waveguide 2 side and the protruding height thereof (the length and height of the alignment projection 8) The impedance matching from the input terminal 5 side can be performed. In addition, since the matching protrusion 8 is provided in the vicinity of the connection portion between the main waveguide 1 and the branch waveguide 2, impedance matching can be performed in a wide band.

  FIG. 3 shows frequency characteristics (a horizontal axis is a normalized frequency and a vertical axis is a reflection loss (dB)) as viewed from input terminals of the T branch waveguide 9 of the present invention and the conventional T branch waveguide shown in FIG. ) Result. In FIG. 3, the solid line indicates the frequency characteristic of the present invention, and the circle symbol indicates the frequency characteristic of the prior art. FIG. 3 shows that the T-branch waveguide 9 of the present invention can perform impedance matching in a wider band than the conventional T-branch waveguide.

  In the above description, an example in which a T-branch waveguide is used as a distributor has been described. However, a T-branch waveguide may be used as a combiner, and a considerable effect can be obtained regarding impedance matching. In this case, the input terminal 5 is an output terminal, and the first and second output terminals 6 and 7 are first and second input terminals, respectively.

  From the above, the main waveguide 1 is the first waveguide, the input terminal 5 is the input / output terminal of the first waveguide, the branching waveguide 2 is the second waveguide, and the first and second output terminals. Reference numerals 6 and 7 constitute first and second input / output terminals of the second waveguide, respectively.

  Further, in the above example, the alignment projection 8 is formed as a bent convex portion in which the surface of the tube is bent to the inside of the tube. For example, as shown in a sectional view similar to FIG. You may form by providing the projection part 80 so that the shape of the inner side of a pipe | tube may become the same inside (on a pipe wall).

Embodiment 2. FIG.
FIG. 5 is a perspective view showing a configuration of a T-branch waveguide according to Embodiment 2 of the present invention, and FIG. 6 is a cross-sectional view taken along line AA of the T-branch waveguide of FIG. 5 and 6, the same or corresponding parts as those in the above embodiment are denoted by the same reference numerals, and description thereof is omitted. As shown in FIGS. 5 and 6, in this embodiment, the protruding amount of the first protrusion 8a on the first output terminal 6 side of the branching waveguide 2 is the second output terminal 7 side. The alignment protrusion 8 is formed so as to be larger than the protrusion amount of the protrusion 8b. Here, the height of the main waveguide 1 and the length of the branching waveguide 2 are larger in the first protrusion 8a on the first output terminal 6 side.

  With such a configuration, when viewed from the input terminal 5, the barrier on the first output terminal 6 side and the barrier on the second output terminal 7 side are asymmetrical, so that the output to the first output terminal 6 is performed. The T-branch waveguide 9 is characterized in that the power to be output and the power output to the second output terminal 7 are different.

  Further, in this embodiment, the height of the first projection 8a and the second projection 8b in the main waveguide 1 and the length in the branch waveguide 2 are changed to realize the asymmetry of the barrier. However, the same effect can be obtained by changing the length in the main waveguide 1 and the height in the branching waveguide 2.

  Further, as in the above embodiment, the above description describes an example in which a T-branch waveguide is used as a distributor. However, a T-branch waveguide may be used as a synthesizer. The protruding portion 8 is formed as a bent convex portion where the surface of the tube is bent to the inside of the tube. However, as shown in FIG. 4, the protruding portion is provided on the inside of the tube so that the inner shape of the tube is the same. May be formed.

It is a perspective view which shows the structure of the T branch waveguide by Embodiment 1 of this invention. It is sectional drawing along the AA line of the T branching waveguide of FIG. It is a figure which shows an example of the reflective characteristic of the T branch waveguide by Embodiment 1 of this invention. It is sectional drawing for demonstrating another example of formation of the protrusion part for a matching of the T branch waveguide by this invention. It is a perspective view which shows the structure of the T branch waveguide by Embodiment 2 of this invention. It is sectional drawing along the AA line of the T branch waveguide of FIG.

Explanation of symbols

  1 main waveguide (first waveguide), 2 branch waveguide (second waveguide), 3 connection port, 4 connection terminal, 5 input terminal (input / output terminal), 6 first output terminal (first 1 input / output terminal), 7 second output terminal (second input / output terminal), 8 alignment projection, 8a first projection, 8b second projection, 8c third projection, 9 T branching conductor Wave tube, 80 protrusions.

Claims (6)

A first waveguide having one end as an input / output terminal and the other end as a connection terminal;
A first input / output terminal at one end, a second input / output terminal at the other end, and a second waveguide having a connection port on one side surface;
In a T-branch waveguide used as a distributor or a combiner in which the connection terminal of the first waveguide and the connection port of the second waveguide are connected,
The second waveguide is connected to the connection portion between the connection terminal of the first waveguide and the connection port of the second waveguide over the entire circumference of the tube of the first waveguide and from the first waveguide. Providing a frame-shaped alignment protrusion that protrudes inward across the wave tube,
A T-branch waveguide characterized by that.   The amount of protrusion of the matching protrusion into the first waveguide and the second waveguide differs between the first input / output terminal side and the second input / output terminal side of the second waveguide, The T-branch waveguide according to claim 1.   3. A distributor having input / output terminals of the first waveguide as input terminals and first and second input / output terminals of the second waveguide as output terminals, respectively. A T-branch waveguide described in 1.   3. A synthesizer having the first and second input / output terminals of the second waveguide as input terminals and the input / output terminal of the first waveguide as output terminals, respectively. A T-branch waveguide described in 1.   5. The T-branch waveguide according to claim 1, wherein the alignment protrusion includes a bent convex portion obtained by bending the surface of the tube toward the inside of the tube.   5. The T-branch waveguide according to claim 1, wherein the alignment protrusion is a protrusion provided inside the tube. 6.

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