WO2021024310A1

WO2021024310A1 - Polarization coupler

Info

Publication number: WO2021024310A1
Application number: PCT/JP2019/030527
Authority: WO
Inventors: 秀憲湯川; 優牛嶋; 素実渡辺; 高橋　徹
Original assignee: 三菱電機株式会社
Priority date: 2019-08-02
Filing date: 2019-08-02
Publication date: 2021-02-11
Also published as: JPWO2021024310A1; JP7012910B2

Abstract

A polarization coupler (1) is provided with: a common wave guide tube (10) that has a short-circuited end (10q) and a input/output terminal (10p) and that has a wave guide space (10h) for allowing transmission of a first polarized wave and a second polarized wave orthogonal to each other; a first rectangular wave guide tube (20) that is connected to the lateral wall of the common wave guide tube (10) and that extends in a first direction intersecting with the tube axis (Ax) direction; and a second rectangular wave guide tube (30) that is connected to the lateral wall of the common wave guide tube (10) and that extends in a second direction intersecting with the tube axis (Ax) direction. The short-circuited end (10q) has a base end portion (10qb) that forms a surface orthogonal to the tube axis (Ax) direction. The first rectangular wave guide tube (20) has a pair of wide wall surfaces that are inclined at an angle of 45 degrees with respect to the base end portion (10qb) on a surface perpendicular to the first direction, whereas the second rectangular wave guide tube (30) has a pair of wide wall surfaces that are inclined at an angle of 45 degrees with respect to the base end portion (10qb) on a surface perpendicular to the second direction.

Description

Demultiplexer

The present invention mainly relates to a demultiplexer that separates a plurality of polarized waves in frequency bands such as VHF (Very High Frequency) band, UHF (Ultra High Frequency) band, microwave band and millimeter wave band.

In wireless communication systems such as satellite communication systems, a plurality of polarizations orthogonal to each other are used for the purpose of effective use of frequencies, and an ortho-mode-transducer for separating the plurality of polarizations. , OMT) is required. This type of demultiplexer is disclosed, for example, in Non-Patent Document 1 below.

In Non-Patent Document 1, a circular waveguide having a short-circuit end at one end and an input / output terminal at the other end and a circular waveguide extending in the vicinity of the short-circuit end so as to branch in opposite directions from each other. A T-junction Ortho-Mode-Transducer equipped with two rectangular waveguides is disclosed. The wide wall surface of the first rectangular waveguide among the two rectangular waveguides is arranged so as to be parallel to the tube axis direction of the circular waveguide, and the two rectangular waveguides are arranged. The wide wall surface of the second rectangular waveguide is arranged so as to be orthogonal to the tube axis direction of the circular waveguide. Such a T-branched demultiplexer separates two linearly polarized waves that are orthogonal to each other input from the input / output terminals of a circular waveguide, and one of the two linearly polarized waves is first rectangularly conducted. It is output from the branch terminal of the wave tube, and the other of the two linearly polarized waves is output from the branch terminal of the second rectangular waveguide.

In the conventional T-branch type demultiplexer disclosed in Non-Patent Document 1, the mutual influence between the branch terminals of the first and second rectangular waveguides is reduced to obtain good demultiplexing characteristics. In order to obtain, the wide wall surface of the first rectangular waveguide is arranged so as to be parallel to the tube axis direction of the circular waveguide, and the wide wall surface of the second rectangular waveguide is of the circular waveguide. Arranged so as to be orthogonal to the direction of the waveguide. As described above, the conventional T-branch type deflector has a geometrically asymmetrical configuration with respect to the tube axis of the circular waveguide, and therefore, from the branch terminal of the first and second rectangular waveguides. The frequency characteristics of the output polarization signals will be different. There is a problem that this hinders the improvement of the demultiplexing characteristic.

In view of the above, an object of the present invention is to provide a demultiplexer capable of making the frequency characteristics of the separated polarized signals the same and realizing excellent demultiplexing characteristics.

The deflector according to one aspect of the present invention has a short-circuit end provided at one end in the axial direction of its own tube and an input / output terminal provided at the other end in the axial direction of its own tube. A common waveguide having a waveguide space for propagating a first polarization component and a second polarization component that are orthogonal to each other between the end and the input / output terminal, a pair of wide walls facing each other, and facing each other. A pair of wide waveguides facing each other and a first rectangular waveguide connected to the side wall of the common waveguide and extending in a first direction orthogonal to the direction of the tube axis. It has a wall surface and a pair of narrow wall surfaces facing each other, and includes a second rectangular waveguide connected to the side wall of the common waveguide and extending in a second direction orthogonal to the tube axis direction. The short-circuit end has a base end portion forming a surface orthogonal to the tube axis direction, and the pair of wide wall surfaces of the first rectangular waveguide is on a surface perpendicular to the first direction. The pair of wide walls of the second rectangular waveguide, inclined at an angle of 45 degrees with respect to the proximal end, are 45 relative to the proximal end in a plane perpendicular to the second direction. It is characterized by being tilted at an angle of degrees.

The demultiplexer according to one aspect of the present invention has a configuration capable of making the frequency characteristics of the polarized signals output from the input / output terminals of the first and second rectangular waveguides the same. Therefore, excellent decentralized wave characteristics can be realized.

It is a perspective view which shows the schematic structure of the partial duplexer of Embodiment 1 which concerns on this invention. It is a front view of the demultiplexer shown in FIG. It is a bottom view of the demultiplexer shown in FIG. 4A is a right side view of the demultiplexer shown in FIG. 1, and FIG. 4B is a left side view of the demultiplexer shown in FIG. It is explanatory drawing which conceptually shows the electric field of the linearly polarized wave signal input to the rectangular waveguide of Embodiment 1. It is explanatory drawing which shows the polarization signal component propagating in the inside of the demultiplexer of Embodiment 1. It is explanatory drawing which shows the polarization signal component propagating in the inside of the demultiplexer of Embodiment 1. It is explanatory drawing which conceptually shows the polarization signal which is output from the common waveguide of Embodiment 1. It is explanatory drawing which conceptually shows the electric field of the linearly polarized wave signal input to the rectangular waveguide of Embodiment 1. It is explanatory drawing which shows the polarization signal component propagating in the inside of the demultiplexer of Embodiment 1. It is explanatory drawing which shows the polarization signal component propagating in the inside of the demultiplexer of Embodiment 1. It is explanatory drawing which conceptually shows the polarization signal which is output from the common waveguide of Embodiment 1. It is explanatory drawing which conceptually shows two polarization signals output from the common waveguide of Embodiment 1. It is a block diagram which shows the schematic structure of the demultiplexer which is a modification of Embodiment 1. It is a perspective view which shows the schematic structure of the partial duplexer of Embodiment 2 which concerns on this invention. FIG. 15 is a right side view of the demultiplexer shown in FIG. It is a rear view of the demultiplexer shown in FIG. It is a bottom view of the demultiplexer shown in FIG. It is explanatory drawing which conceptually shows two linearly polarized wave signals output from the common waveguide of Embodiment 1. It is a perspective view which shows the schematic structure of the partial demultiplexer of Embodiment 3 which concerns on this invention. 21A is a right side view of the demultiplexer shown in FIG. 20, and FIG. 21B is a left side view of the demultiplexer shown in FIG. 20. 22A and 22B are diagrams schematically showing the configuration of the short-circuit end of the third embodiment. 23A and 23B are diagrams schematically showing the configuration of the short-circuit end in the first modification of the third embodiment. 24A and 24B are diagrams schematically showing the configuration of the short-circuit end in the second modification of the third embodiment. 25A and 25B are diagrams schematically showing the configuration of the short-circuit end in the third modification of the third embodiment. It is a perspective view which shows the schematic structure of the partial duplexer of Embodiment 4 which concerns on this invention. It is a rear view of the demultiplexer shown in FIG. It is a rear view of the demultiplexing device of the 1st modification of Embodiment 4. 29A and 29B are perspective views showing a schematic configuration of a demultiplexer according to a second modification of the fourth embodiment. It is a graph which shows the calculation example of the reflection characteristic about the demultiplexer of the 2nd modification of Embodiment 4. It is a graph which shows the calculation example of the isolation characteristic between polarizations about the demultiplexer of the 2nd modification of Embodiment 4.

Hereinafter, various embodiments according to the present invention will be described in detail with reference to the drawings. It should be noted that the components having the same reference numerals in the entire drawing shall have the same configuration and the same function. Further, the X-axis, Y-axis and Z-axis shown in the drawings shall be orthogonal to each other.

Embodiment 1.
FIG. 1 is a perspective view showing a schematic configuration of a demultiplexer 1 according to a first embodiment of the present invention. 2 is a front view of the demultiplexer shown in FIG. 1, FIG. 3 is a bottom view of the demultiplexer shown in FIG. 1, and FIG. 4A is a bias shown in FIG. It is a right side view of the demultiplexer, and FIG. 4B is a left side view of the demultiplexer shown in FIG.

As shown in FIG. 1, the deflector 1 of the present embodiment is configured to include a common waveguide 10 and

rectangular waveguides

20 and 30 branching from the side wall of the common waveguide 10. There is. The common waveguide 10 is composed of a circular waveguide having a tube axis Ax parallel to the Z-axis direction, and has a short-circuit end 10q provided at one end in the tube axis direction and an open end provided at the other end in the tube axis direction. A waveguide that propagates an electromagnetic wave consisting of two polarization components (first and second polarization components) orthogonal to each other between a certain input / output terminal 10p, a short-circuit end 10q, and the input / output terminal 10p in the tube axis direction. It has a space of 10h. The common waveguide 10 of the present embodiment can mainly propagate the TE ₁₁ mode.

The short-circuit end 10q has an annular base end portion 10qb forming a plane orthogonal to the tube axis Ax, and a protrusion 10qc protruding from the base end portion 10qb toward the input / output terminal 10p. As shown in FIGS. 1 to 4, the protrusion 10qc has a truncated cone shape geometrically symmetrical with respect to the tube axis Ax, and the position of the tip portion of the protrusion 10qc coincides with the tube axis Ax. The protrusion 10qc of the present embodiment has a cross section that continuously changes from the base end portion 10qb toward the input / output terminal 10p, but is not limited thereto. The shape of the protrusion 10qc may be changed so as to have a cross section that gradually changes from the base end portion 10qb toward the input / output terminal 10p.

On the other hand, the rectangular waveguide (first rectangular waveguide) 20 is composed of a pair of wide wall surfaces facing each other and a pair of narrow walls facing each other, as shown in FIGS. 1 to 3 and 4B. It has an inner wall surface. Here, the wide wall surface means an inner wall surface forming the long side of the rectangular cross section of the rectangular waveguide 20 as shown in FIG. 4B, and the narrow wall surface forms the short side of the rectangular cross section. It means the inner wall surface. Further, the rectangular waveguide 20 is arranged so as to extend from the side wall of the common waveguide 10 in the negative direction of the Y axis (first direction) in the vicinity of the short-circuit end 10q of the common waveguide 10. The waveguide space 20h inside the rectangular waveguide 20 communicates with the waveguide space 10h of the common waveguide 10 via a coupling hole. An input / output terminal (branch terminal) 20p is provided at one end of the rectangular waveguide 20.

The rectangular waveguide (second rectangular waveguide) 30 has the same waveguide structure as the rectangular waveguide 20. As shown in FIGS. 1 to 3 and 4A, the rectangular waveguide 30 has an inner wall surface composed of a pair of wide wall surfaces facing each other and a pair of narrow wall surfaces facing each other. Here, the wide wall surface means an inner wall surface forming the long side of the rectangular cross section of the rectangular waveguide 30 as shown in FIG. 4A, and the narrow wall surface forms the short side of the rectangular cross section. It means the inner wall surface. Further, the rectangular waveguide 30 is arranged so as to extend in the Y-axis positive direction (second direction) from the side wall of the common waveguide 10 in the vicinity of the short-circuit end 10q of the common waveguide 10. The waveguide space 30h inside the rectangular waveguide 30 communicates with the waveguide space 10h of the common waveguide 10 via a coupling hole. An input / output terminal (branch terminal) 30p is provided at one end of the rectangular waveguide 30.

As shown in FIGS. 2, 4A and 4B, the protrusion 10qc at the short-circuit end 10q faces the coupling hole formed between the rectangular waveguide 20 and the common waveguide 10, and is a rectangular waveguide. It also faces the coupling hole formed between 30 and the common waveguide 10. Such a protrusion 10qc can serve a function of blocking signal propagation between the

rectangular waveguides

20 and 30.

The

rectangular waveguides

20 and 30 described above extend in opposite directions (Y-axis negative direction and Y-axis positive direction) on a plane perpendicular to the tube axis direction of the common waveguide 10, respectively, and the tube axis Ax. They are arranged so that they are geometrically symmetrical with respect to each other. As shown in FIG. 4A, the wide wall surface of the rectangular waveguide 30 is inclined counterclockwise at an angle of θ1 = 45 ° with respect to the base end portion 10qb of the short-circuit end 10q in the XX plane. On the other hand, as shown in FIG. 4B, the wide wall surface of the rectangular waveguide 20 is inclined clockwise at an angle of θ2 = 45 ° with respect to the base end portion 10qb of the short-circuit end 10q in the XX plane. ..

Such a demultiplexer 1 may be manufactured by processing and welding a metal alloy material. Alternatively, the demultiplexer 1 integrally forms the common waveguide 10 and the

rectangular waveguides

20 and 30 by laminating and molding a metal powder such as an aluminum alloy (AlSi ₁₀ Mg) using a metal 3D printer. It may be produced by the above. For example, as a method of a metal 3D printer, a laser sintering method (Selective Laser Sintering, SLS), a direct metal laser sintering method (DMLS), a laser melting method (Selective Laser Melting, SLM), and an electron beam are used. A melting method (Electron Beam Melting, EBM) or a laser direct laminating method (Laser Engineering Net Shipping, LENS) can be used. It should be noted that the second to fourth embodiments described later and modified examples thereof can also be produced by the same method as that of the demultiplexer 1.

When using a metal 3D printer, it is difficult to form a flat plate perpendicular to the stacking direction because the demultiplexer 1 is formed by laminating metal alloy materials one layer at a time according to the design data. As described above, the conventional T-branch waveguide disclosed in Non-Patent Document 1 has two rectangular waveguides extending from the side wall of the circular waveguide so as to branch in opposite directions. Both of these two rectangular waveguides have a wall surface perpendicular to the tube axis direction of the circular waveguide. Therefore, when the wall surfaces of these rectangular waveguides are laminated and modeled using a metal 3D printer, the axial direction of the circular waveguide must be tilted by a predetermined angle (for example, 45 degrees) from the stacking direction. This may reduce the molding accuracy of the circular waveguide or increase the cost due to the increase in the laminated area. On the other hand, in the case of the demultiplexer 1 of the present embodiment, as shown in FIGS. 4A and 4B, the wide wall surfaces of the

rectangular waveguides

20 and 30 are oriented with respect to the tube axis direction of the common waveguide 10. Since it is tilted at 45 degrees, the metal 3D printer can laminate and model the metal alloy material along the tube axis direction of the common waveguide 10. As a result, it is possible to improve the modeling accuracy of the common waveguide 10 and reduce the cost of the demultiplexer 1.

Next, the operation of the demultiplexer 1 of the first embodiment will be described with reference to FIGS. 5 to 13.

First, the operation when a linearly polarized wave signal is input to the input / output terminal 30p of the rectangular waveguide 30 will be described below. FIG. 5 is a diagram conceptually showing the electric field E1 of the linearly polarized wave signal input to the input / output terminal 30p of the rectangular waveguide 30. This electric field E1 can be considered as the vector sum of two electric field components E1x and E1z that are orthogonal to each other. At this time, the electric field component E1x is converted into the electric field component E2x when propagating from the input / output terminal 30p of the rectangular waveguide 30 to the input / output terminal 10p of the common waveguide 10 as shown in FIG. Since the protrusion 10qc blocks the propagation of the electric field component E1x between the

rectangular waveguides

20 and 30, the amount of the electric field component leaking from the rectangular waveguide 30 to the rectangular waveguide 20 can be made very small. it can.

On the other hand, the electric field component E1z is converted into the electric field component E2y when propagating from the input / output terminal 30p of the rectangular waveguide 30 to the input / output terminal 10p of the common waveguide 10 as shown in FIG. Since the protrusion 10qc blocks the propagation of the electric field component E1z between the

rectangular waveguides

20 and 30, the amount of the electric field component leaking from the rectangular waveguide 30 to the rectangular waveguide 20 can be made very small. it can. As shown in FIG. 8, the signal output from the input / output terminal 10p of the common waveguide 10 is a polarization signal having an electric field E2 which is a vector sum of the electric field components E2x and E2y.

Next, the operation when a linearly polarized wave signal is input to the input / output terminal 20p of the rectangular waveguide 20 will be described below. FIG. 9 is a diagram conceptually showing the electric field E3 of the linearly polarized wave signal input to the input / output terminal 20p of the rectangular waveguide 20. This electric field E3 can be considered as the vector sum of two electric field components E3x and E3z that are orthogonal to each other. At this time, the electric field component E3x is converted into the electric field component E4x when propagating from the input / output terminal 20p of the rectangular waveguide 20 to the input / output terminal 10p of the common waveguide 10 as shown in FIG. Since the protrusion 10qc blocks the propagation of the electric field component E4x between the

rectangular waveguides

20 and 30, the amount of the electric field component leaking from the rectangular waveguide 20 to the rectangular waveguide 30 can be made very small. it can.

On the other hand, the electric field component E3z is converted into the electric field component E4y when propagating from the input / output terminal 20p of the rectangular waveguide 20 to the input / output terminal 10p of the common waveguide 10 as shown in FIG. Since the protrusion 10qc blocks the propagation of the electric field component E4y between the

rectangular waveguides

20 and 30, the amount of the electric field component leaking from the rectangular waveguide 20 to the rectangular waveguide 30 can be made very small. it can. As shown in FIG. 12, the signal output from the input / output terminal 10p of the common waveguide 10 is a polarization signal having an electric field E4 which is a vector sum of the electric field components E4x and E4y.

Therefore, when linearly polarized signals are input to the input /

output terminals

20p and 30p, respectively, the input / output terminals 10p of the common waveguide 10 have the electric field E2 shown in FIG. 8 as shown in FIG. The polarization signal and the polarization signal having the electric field E4 shown in FIG. 12 can be output. These linearly polarized signals are orthogonal to each other. In other words, when electromagnetic waves including polarization signals that are orthogonal to each other are input from the input / output terminals 10p of the common waveguide 10, the polarization demultiplexer 1 separates these polarization signals and performs the polarization. One of the signals can be output from the input / output terminal 20p of the rectangular waveguide 20, and the other of the polarized signals can be output from the input / output terminal 30p of the rectangular waveguide 30.

As described above, unlike the conventional T-branch type demultiplexer disclosed in Non-Patent Document 1, the demultiplexer 1 of the first embodiment is input / output of the

rectangular waveguides

20 and 30. It has a configuration in which the frequency characteristics of the polarization signals output from the

terminals

20p and 30p can be made the same. Therefore, excellent demultiplexing characteristics (for example, isolation characteristics between input / output terminals, isolation characteristics between polarizations, and reflection characteristics) can be realized.

The conventional T-branched waveguide disclosed in Non-Patent Document 1 has two rectangular waveguides branched from the side wall of the circular waveguide, but has an asymmetric structure. Therefore, if the frequency characteristics of the polarization signal output from one of the two rectangular waveguides are optimized, the frequency characteristics of the polarization signal output from the other rectangular waveguide can be optimized. Will deteriorate. Further, if the matching between one rectangular waveguide and the circular waveguide is improved, there is a problem that the matching between the other rectangular waveguide and the circular waveguide is deviated. On the other hand, in the case of the present embodiment, as shown in FIGS. 1 to 3 and 4A and 4B, the

rectangular waveguides

20 and 30 are on a plane perpendicular to the tube axis direction of the common waveguide 10. Since they extend in opposite directions and are arranged so as to be geometrically symmetrical with respect to the tube axis Ax, the deflector 1 is geometrically arranged with respect to the XZ plane including the tube axis direction. It has a symmetrical structure. Therefore, as compared with the conventional T-branch type demultiplexer, the matching between the

rectangular waveguides

20 and 30 and the common waveguide 10 can be easily adjusted.

FIG. 14 is a block diagram showing a schematic configuration of a demultiplexer 1A, which is a modification of the first embodiment. As shown in FIG. 14, the demultiplexer 1A has a configuration in which the 90-degree hybrid coupler 9 is connected to the input /

output terminals

20p and 30p of the demultiplexer 1 of the first embodiment. The 90-degree hybrid coupler 9 has four input /

output terminals

9a, 9b, 9c, and 9d, and the input /

output terminals

9a and 9b are coupled to the input /

output terminals

20p and 30p of the demultiplexer 1, respectively. When a polarization signal (for example, TE ₁₀ mode) is input to either one of the input /

output terminals

9c and 9d, the 90-degree hybrid coupler 9 transmits a polarization signal having a phase difference of 90 degrees to the input / output terminals 9a, Output from 9b to input /

output terminals

30p and 20p. When a polarization signal is input to the input / output terminal 9c, the demultiplexer 1 can output right-handed circularly polarized light from the input / output terminal 10p, and the polarization signal is input to the input / output terminal 9d. In this case, the demultiplexer 1 can output left-handed circularly polarized light from the input / output terminal 10p. Therefore, the demultiplexer 1A can operate as a circularly polarized wave separator. For example, the input / output terminal 9c of the 90-degree hybrid coupler 9 can be used as a terminal for signal transmission, and the input / output terminal 9d of the 90-degree hybrid coupler 9 can be used as a terminal for signal reception.

Since the 90-degree hybrid coupler 9 can be configured to have a geometrically symmetrical structure, the demultiplexer 1A can be configured to have a geometrically symmetrical structure as a whole. Therefore, the demultiplexer 1A can have excellent demultiplexing characteristics.

Embodiment 2.
Next, the second embodiment according to the present invention will be described. FIG. 15 is a perspective view showing a schematic configuration of a demultiplexer 2 according to a second embodiment of the present invention. 16 is a right side view of the demultiplexer 2 shown in FIG. 15, FIG. 17 is a rear view of the demultiplexer 2 shown in FIG. 15, and FIG. 18 is a rear view of FIG. It is a bottom view of the demultiplexer 2 shown.

As shown in FIG. 15, the demultiplexer 2 of the second embodiment branches from the common waveguide 10 and the side wall of the common waveguide 10, similarly to the demultiplexer 1 of the first embodiment. It is configured to include

rectangular waveguides

20 and 30. The configuration of the demultiplexer 2 is the same as the configuration of the demultiplexer 1 of the first embodiment except for the connection form between the common waveguide 10 and the rectangular waveguide 20.

In the present embodiment, the rectangular waveguide 20 extends in the negative X-axis direction (first direction) from the side wall of the common waveguide 10 in the vicinity of the short-circuit end 10q of the common waveguide 10. The rectangular waveguide 30 is arranged so as to extend in the Y-axis positive direction (second direction) from the side wall of the common waveguide 10 in the vicinity of the short-circuit end 10q. The waveguide space 20h inside the rectangular waveguide 20 communicates with the waveguide space 10h of the common waveguide 10 via a coupling hole.

Further, as shown in FIGS. 16 and 17, the protruding portion 10qc of the short-circuit end 10q faces the coupling hole formed between the rectangular waveguide 20 and the common waveguide 10, and is opposed to the rectangular waveguide 30. It also faces the coupling hole formed between the common waveguide 10. Such a protrusion 10qc can serve a function of blocking signal propagation between the

rectangular waveguides

20 and 30.

As shown in FIG. 18, the

rectangular waveguides

20 and 30 extend in directions orthogonal to each other (X-axis negative direction and Y-axis positive direction) on the plane orthogonal to the tube axis direction of the common waveguide 10. doing. The cross-sectional shape of the rectangular waveguide 20 shown in FIG. 16 matches the cross-sectional shape of the rectangular waveguide 30 shown in FIG. As shown in FIG. 16, the wide wall surface of the rectangular waveguide 30 is inclined counterclockwise at an angle of θ1 = 45 ° with respect to the base end portion 10qb of the short-circuit end 10q in the XX plane. On the other hand, as shown in FIG. 17, the wide wall surface of the rectangular waveguide 20 is inclined counterclockwise at an angle of θ3 = 45 ° with respect to the base end portion 10qb of the short-circuit end 10q in the YY plane. There is.

When linearly polarized signals are input to the input /

output terminals

20p and 30p of the

rectangular waveguides

20 and 30 of the demultiplexer 2 as in the case of the first embodiment, as shown in FIG. The input / output terminal 10p of the common waveguide 10 can output a polarization signal having an electric field E2 and a polarization signal having an electric field E5. These polarized signals are orthogonal to each other. In other words, when electromagnetic waves including polarization signals that are orthogonal to each other are input from the input / output terminals 10p of the common waveguide 10, the polarization demultiplexer 2 separates these polarization signals and performs the polarization. One of the signals can be output from the input / output terminal 20p of the rectangular waveguide 20, and the other of the polarized signals can be output from the input / output terminal 30p of the rectangular waveguide 30.

As described above, similarly to the demultiplexer 1 of the first embodiment, the demultiplexer 2 of the second embodiment is also output from the input /

output terminals

20p and 30p of the

rectangular waveguides

20 and 30, respectively. It has a configuration in which the frequency characteristics of the polarized signals can be made the same. Therefore, excellent demultiplexing characteristics can be realized. Further, as compared with the first embodiment, since the

rectangular waveguides

20 and 30 are arranged at positions closer to each other, the size of the demultiplexer 2 can be reduced.

Embodiment 3.
Next, the third embodiment according to the present invention will be described. FIG. 20 is a perspective view showing a schematic configuration of a demultiplexer 3 according to a third embodiment of the present invention. 21A is a right side view of the demultiplexer 3 shown in FIG. 20, and FIG. 21B is a left side view of the demultiplexer 3 shown in FIG. 20.

As shown in FIG. 20, the deflector 3 of the third embodiment includes a common waveguide 11 and

rectangular waveguides

20 and 30 branching from the side wall of the common waveguide 11. There is. The configuration of the demultiplexer 3 is the same as that of the demultiplexer 1 of the first embodiment, except that the common waveguide 11 of FIG. 20 is provided instead of the common waveguide 10 of the first embodiment. It is the same.

The common waveguide 11 is composed of a circular waveguide having a tube axis Ax parallel to the Z-axis direction, and has a short-circuit end 11q provided at one end in the tube axis direction and an open end provided at the other end in the tube axis direction. A waveguide that propagates an electromagnetic wave consisting of two polarization components (first and second polarization components) orthogonal to each other between a certain input / output terminal 11p, a short-circuit end 11q, and the input / output terminal 11p in the tube axis direction. It has a space of 11h. The common waveguide 11 of the present embodiment can mainly propagate the TE ₁₁ mode.

The short-circuit end 11q has an annular base end 11qb forming a plane orthogonal to the tube axis Ax, and a protrusion 11qc protruding from the base end 11qb toward the input / output terminal 11p. The protrusion 11qc has an elliptical frustum shape eccentric from the tube axis Ax. As shown in FIGS. 21A and 21B, the protrusion 11qc faces the coupling hole formed between the rectangular waveguide 20 and the common waveguide 11, and the rectangular waveguide 30 and the common waveguide 11 face each other. It also faces the coupling hole formed between and.

As shown in FIGS. 22A and 22B, the protrusion 11qc has an elliptical columnar tip portion 11qt on its own body portion, and the tip portion 11qt is offset (eccentric) from the tube axis Ax of the common waveguide 11. ) Is placed at the position. Since the effect of blocking signal propagation between the

rectangular waveguides

20 and 30 is improved by such a tip portion 11qt, it is possible to improve the partial wave separation characteristic. A columnar tip portion may be provided instead of the elliptical columnar tip portion 11qt.

As shown in FIG. 22A, the protrusion 11qc of the present embodiment has an inclined portion that changes linearly from the base end portion 11qb toward the input / output terminal 11p, but is limited to this. is not it. The shape of the protrusion 11qc may be changed so as to have an inclined portion that changes in a curved shape from the base end portion 11qb toward the input / output terminal 11p. 23A and 23B are diagrams schematically showing the configuration of the short-circuit end 11u in the common waveguide 11A of the first modification of the third embodiment. As shown in FIGS. 23A and 23B, the short-circuit end 11u is an annular base end portion 11ub forming a plane orthogonal to the tube axis Ax, and the base end portion 11ub to the input / output terminal of the common waveguide 11A. It has a protrusion 11 uc that projects toward it. The protrusion 11 uc has an elliptical columnar tip portion 11 ut on its own main body portion, and has an inclined portion that changes in a curved shape from the base end portion 11 ub toward the input / output terminal of the common waveguide 11 A. ing.

Further, as shown in FIG. 22A, the protrusion 11qc of the present embodiment has a cross section that continuously changes from the base end portion 11qb toward the input / output terminal 11p, but is limited to this. It's not a thing. The shape of the protrusion 11qc may be changed so as to have a cross section that gradually changes from the base end portion 11qb toward the input / output terminal 11p. 24A and 24B are diagrams schematically showing the configuration of the short-circuit end 11s in the common waveguide 11B of the second modification of the third embodiment. As shown in FIGS. 24A and 24B, the short-circuit end 11s is an annular base end portion 11sb forming a plane orthogonal to the tube axis Ax, and the base end portion 11sb to the input / output terminal of the common waveguide 11B. It has a protrusion 11 sc that projects toward it. The protruding portion 11sc has an elliptical columnar tip portion 11st on its own main body portion, and has a cross section that gradually changes from the base end portion 11sb toward the input / output terminal of the common waveguide 11B. There is.

25A and 25B are diagrams schematically showing the configuration of the short-circuit end 11v in the common waveguide 11C of the third modification of the third embodiment. As shown in FIGS. 25A and 25B, the short-circuit end 11v is an annular base end portion 11vb forming a plane orthogonal to the tube axis Ax, and the base end portion 11vb to the input / output terminal of the common waveguide 11C. It has a quadrangular pyramid-shaped protrusion 11 vc that protrudes toward it. The protrusion 11vc has a square columnar tip portion 11vt on its own main body portion. Note that the example of FIG. 25A has a cross section that continuously changes from the base end portion 11vb toward the input / output terminal of the common waveguide 11C, but is not limited to this. The shape of the protrusion 11vc may be changed so as to have a cross section that changes stepwise from the base end portion 11vb toward the input / output terminal of the common waveguide 11C.

As described above, in the third embodiment, the protrusion 11qc of the demultiplexer 3 has a tip portion 11qt, and the tip portion 11qt is a position offset (eccentric) from the tube axis Ax of the common waveguide 11. It is located in. Since the effect of blocking signal propagation between the

rectangular waveguides

20 and 30 is improved by such a tip portion 11qt, it is possible to improve the partial wave separation characteristic.

Embodiment 4.
Next, the fourth embodiment according to the present invention will be described. FIG. 26 is a perspective view showing a schematic configuration of a demultiplexer 4 according to a fourth embodiment of the present invention. FIG. 27 is a rear view of the demultiplexer 4 shown in FIG. 26.

As shown in FIG. 26, the deflector 4 of the present embodiment is configured to include a common waveguide 12 and

rectangular waveguides

21 and 31 branching from the side wall of the common waveguide 12. There is. The common waveguide 112 includes a waveguide portion 13 composed of a circular waveguide having a tube axis Ax parallel to the Z-axis direction, and a coupling guide that is longitudinally connected to the waveguide portion 13 and functions as an impedance transformer. It includes a waveguide 14. An input / output terminal 13p is provided at one end of the waveguide portion 13. For example, as the coupled waveguide section 14, a circular waveguide having a cross-sectional dimension different from that of the waveguide section 13 can be used. As shown in FIGS. 26 and 27, one end of the coupled waveguide section 14 is provided with a short-circuit end 14q having a structure similar to that of any of the short-circuit ends of the first to third embodiments.

The rectangular waveguide (first rectangular waveguide) 21 is connected to a rectangular waveguide portion 22 having an input / output terminal 22p and a coupling guide that is vertically connected to the rectangular waveguide portion 22 and functions as an impedance modifier. It includes a waveguide 23. As the coupled waveguide section 23, a rectangular waveguide having a cross-sectional dimension different from that of the rectangular waveguide section 22 can be used.

The rectangular waveguide (second rectangular waveguide) 31 is connected to a rectangular waveguide portion 32 having an input / output terminal 32p and a coupling guide that is longitudinally connected to the rectangular waveguide portion 32 and functions as an impedance modifier. It includes a waveguide 33. As the coupled waveguide section 33, a rectangular waveguide having a cross-sectional shape different from that of the rectangular waveguide section 32 can be used.

By using the coupled

waveguides

14, 23, 33 that function as an impedance transformer in this way, impedance matching can be easily achieved, and even better decentralized wave characteristics can be realized.

Instead of the form shown in FIG. 27, there may be a demultiplexer 4A having a form in which the coupled

waveguides

23 and 33 straddle the short-circuit end 14q as shown in FIG. 28. Further, in the present embodiment, each of the coupled

waveguide portions

14, 23, and 33 is provided in only one stage, but the present invention is not limited to this, and two or more stages of coupled waveguide portions are provided. You may.

29A and 29B are diagrams showing a schematic configuration of a demultiplexer 4B of the second modification of the fourth embodiment. The configuration of the demultiplexer 4B is as shown in FIG. 26, except that the short-circuited ends 14q and the coupled

waveguides

23 and 33 form a continuous outer wall surface (cut plane). This is the same as the configuration of the deflector 4 of Form 4. The short-circuit end 14q has the same structure as the short-circuit end 11q shown in FIG.

FIG. 30 is a graph showing a calculation example of the reflection characteristic of the demultiplexer 4B of the second modification, and FIG. 31 is a graph showing a calculation example of the interpolar isolation characteristic of the demultiplexer 4B. is there. The horizontal axis of the graphs of FIGS. 30 and 31 indicates the normalized frequency. The vertical axis of the graph of FIG. 30 shows the amount of reflection (unit: dB) of the input /

output terminals

22p and 32p of the

rectangular waveguides

21 and 31. In FIG. 30, the solid line represents the reflection amount of the input / output terminal 22p of the rectangular waveguide 21, and the dotted line represents the reflection amount of the input / output terminal 32p of the rectangular waveguide 31. Further, the vertical axis of the graph of FIG. 31 is the amount (isolation between polarizations) that one linearly polarized wave input from the input / output terminal 13p of the common waveguide 12 is output to the input / output terminal (branch terminal) that is not originally output. The ratio: XPD) (unit: dB) is shown. In FIG. 31, the solid line represents the amount output to the input / output terminal 22p of the rectangular waveguide 21, and the dotted line represents the amount output to the input / output terminal 32p of the rectangular waveguide 31. As shown in FIGS. 30 and 31, both the solid line and the dotted line almost overlap and show the same decentralized wave characteristics, and the reflection amount is 25 dB and the isolation between polarizations is 25 dB or more in a specific band of 15% or more. It was confirmed that good partial isolation characteristics can be obtained.

Embodiments 1 to 4 and modified examples thereof according to the present invention have been described above with reference to the drawings, but embodiments 1 to 4 and modified examples thereof are examples of the present invention, and various other examples. There may also be embodiments. Within the scope of the present invention, it is possible to freely combine the above embodiments 1 to 4, modify any component of each embodiment, or omit any component of each embodiment.

For example, the above-mentioned

common waveguides

10, 11, 11A to 11C, 12 are all circular waveguides, but the present invention is not limited thereto. A square waveguide may be used instead of the circular waveguide. When a square waveguide is used, it has the effect of facilitating manufacturing by cutting.

Further, as in the case of the first embodiment, the 90-degree hybrid coupler 9 of FIG. 14 may be connected to the demultiplexers 2 to 4 of the second to fourth embodiments.

The demultiplexer according to the present invention is suitable for use in, for example, a radio telescope for astronomical observation, a satellite communication system, and an antenna device in a satellite broadcasting system.

1,1A, 2-4, 4A, 4B demultiplexer, 9 90 degree hybrid coupler, 9a-9d terminal, 10 common waveguide, 10p input / output terminal, 10q short-circuit end, 10qc protrusion, 10qb base end 10h waveguide space, 11, 11A-11C common waveguide, 11p input / output terminal, 11q, 11u, 11s, 11v short-circuit end, 11qb, 11ub, 11sb, 11vb base end, 11qc, 11uc, 11sc, 11vc protrusion Part, 11qt, 11ut, 11st, 11vt tip part, 12 common waveguide, 13 waveguide, 14 coupled waveguide, 20 rectangular waveguide, 20p input / output terminal, 20h waveguide space, 21 rectangular guide Waveguide, 22 rectangular waveguide, 23 coupled waveguide, 30 rectangular waveguide, 30p input / output terminal, 30h waveguide space, 31 rectangular waveguide, 32 rectangular waveguide, 33 coupled waveguide Pipe section.

Claims

It has a short-circuit end provided at one end in its own tube axis direction and an input / output terminal provided at the other end in its own tube axis direction, and is orthogonal to each other between the short-circuit end and the input / output terminal. A common waveguide having a waveguide space for propagating the first polarization component and the second polarization component.
A first rectangular guide having a pair of wide walls facing each other and a pair of narrow walls facing each other, connected to the side wall of the common waveguide and extending in a first direction orthogonal to the axial direction of the tube. Waveguide and
A second rectangular guide having a pair of wide walls facing each other and a pair of narrow walls facing each other, connected to the side wall of the common waveguide and extending in a second direction orthogonal to the axial direction of the tube. Equipped with a waveguide,
The short-circuit end has a base end portion that forms a surface orthogonal to the pipe axis direction.
The pair of wide walls of the first rectangular waveguide are tilted at an angle of 45 degrees with respect to the proximal end in a plane perpendicular to the first direction.
The pair of wide walls of the second rectangular waveguide are inclined at an angle of 45 degrees with respect to the proximal end in a plane perpendicular to the second direction.
A demultiplexer characterized by that.
The demultiplexer according to claim 1, wherein the first rectangular waveguide and the second rectangular waveguide have the same waveguide structure.
The deflector according to claim 1 or 2, wherein the first rectangular waveguide and the second rectangular waveguide are opposite to each other in a plane perpendicular to the tube axis direction. A demultiplexer characterized in that it extends to each of the common waveguides and is arranged so as to be geometrically symmetrical with respect to the tube axis of the common waveguide.
The demultiplexer according to claim 1 or 2.
The first rectangular waveguide and the second rectangular waveguide extend in directions orthogonal to each other on a plane orthogonal to the tube axis direction, respectively.
The cross-sectional shape of the first rectangular waveguide in a plane perpendicular to the first direction coincides with the cross-sectional shape of the second rectangular waveguide in a plane perpendicular to the second direction.
A demultiplexer characterized by that.
The demultiplexer according to any one of claims 1 to 4.
The short-circuit end has a protrusion that protrudes from the base end toward the input / output terminal.
The protrusion faces the coupling hole formed between the first rectangular waveguide and the common waveguide, and is between the second rectangular waveguide and the common waveguide. A waveguide characterized in that it faces a coupling hole formed in.
The truncated cone shape or an elliptical truncated cone shape according to claim 5, wherein the protrusion has a cross section that changes continuously or stepwise from the base end portion toward the input / output terminal. A demultiplexer characterized by having.
The quadrangular pyramid shape according to claim 5, wherein the protrusion has a cross section that changes continuously or stepwise from the base end portion toward the input / output terminal. Characteristic demultiplexer.
The demultiplexing device according to any one of claims 5 to 7, wherein the protrusion has a cylindrical or elliptical columnar tip portion.
The demultiplexer according to claim 8, wherein the tip portion of the protrusion is arranged at a position offset from the tube axis of the common waveguide.
The demultiplexing device according to claim 9, wherein the tip portion thereof is a columnar or elliptical columnar shape.
The demultiplexer according to any one of claims 1 to 10.
The common waveguide
The waveguide having the input / output end and
A demultiplexer having the short-circuited end and having a coupled waveguide section that is longitudinally connected to the waveguide section and functions as an impedance transformer.
The demultiplexer according to any one of claims 1 to 11.
The first rectangular waveguide
The first rectangular waveguide
It has a first coupled waveguide section that is connected to the side wall of the common waveguide and is longitudinally connected to the first rectangular waveguide section to function as an impedance transformer.
The second rectangular waveguide
The second rectangular waveguide and
It has a second coupled waveguide section that is connected to the side wall of the common waveguide and is longitudinally connected to the second rectangular waveguide section to function as an impedance transformer.
A demultiplexer characterized by that.
The deflecting wave device according to claim 12, wherein the base end portion, the first coupled waveguide portion, and the second coupling waveguide portion form a continuous outer wall surface. A deflector that features.
The demultiplexer according to any one of claims 1 to 13, wherein the input / output terminal of the first rectangular waveguide and the input of the second rectangular waveguide. A deflector characterized by further comprising a 90 degree hybrid coupler connected to an output terminal.
The demultiplexer according to any one of claims 1 to 14, wherein the common waveguide, the first rectangular waveguide, and the second rectangular waveguide are A demultiplexing director, characterized in that it is a modeled object integrally formed by laminating and modeling metal powder using a metal 3D printer.