JPH0715203A - Primary radiator for common use of circularly polarized wave and linearly polarized wave - Google Patents

Abstract

PURPOSE:To output a signal from one rectangular waveguide joined to a circular waveguide by selecting any desired wave out of a circularly polarized wave (right turning and left turning circularly polarized waves) introduced to the circular waveguide and a linearly polarized wave (horizontally and vertically polarized waves). CONSTITUTION:This device is composed of a ferrite bar 5 arranged at the center of a circular waveguide 2 on the side of an opening part 1 inside the circular waveguide 1 so that the lengthwise direction can be parallel to the axis of the tube, excited coil 4 for impressing a DC magnetic field to the ferrite bar 5, and rectangular waveguide 6 provided as the output means and electromagnetic waves on the side of a terminal end face 3. A desired signal to be received is provided from an output means by selecting either the horizontally polarized wave or the vertically polarized wave while setting a value within a Faraday rotating area for the DC magnetic field of the ferrite bar, either the right turning circularly polarized wave or the left turning circularly polarized wave is absorbed by the magnetic resonance phenomenon of the positive circularly polarized wave while setting a value within a magnetic resonance area for the DC magnetic field of the ferrite bar 5, and the desired signal to be received is provided from the output means so that the other wave desired to be received can be a negative circularly polarized wave.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a satellite broadcasting (BS) using circular polarization and a communication satellite (CS) using linear polarization (horizontal polarization and vertical polarization). , For both circularly polarized and linearly polarized primary radiators capable of receiving both.

[0002]

2. Description of the Related Art As shown in FIG. 9 (A), a conventional BS and CS common antenna has a BS primary radiator 17 and a CS primary radiator 18 mounted side by side on the same reflector 16 and a focal point of the reflector 16. Slide the reflector 1
The primary radiator 17 for BS is positioned at the focal point of one end of the reflector 6, and the primary radiator 18 for CS is positioned at the focal point of the other end of the reflector 16 so that the orientation of the reflector 16 of each satellite is changed. It was oriented so that it could receive BS radio waves and CS radio waves.

[0003]

Therefore, the reflector 1
There is a problem that the gain obtained by each primary radiator is reduced because the focus of 6 is deviated, and the structure becomes complicated because two primary radiators are attached to the same reflector 16. There were also problems. The present invention provides a primary radiator that can be commonly used for BS and CS.
The primary radiator 20 is arranged at the focal point of the reflector 19 as shown in FIG.
9 is directed toward the broadcasting satellite, and when receiving CS, the reflector 19 is directed toward the communication satellite so that the BS and CS radio waves can be received by the same primary radiator 20. The structure is simple and the price is low. The aim is to provide a cheap, economical receiving system for.

[0004]

FIG. 1 is a partially cutaway perspective view of a primary radiator for both circularly polarized waves and linearly polarized waves, showing an embodiment of the present invention. As shown in FIG. A circular waveguide 2 having an opening 1 for introducing an electromagnetic wave at one end and a terminating surface 3 at the other end, and an opening 1 side inside the circular waveguide 2,
A ferrite rod 5 arranged at the center of the circular waveguide 2 with its longitudinal direction parallel to the tube axis; an exciting coil 4 wound directly on the ferrite rod 5 to apply a DC magnetic field to the ferrite rod 5; On the end face 3 side of the circular waveguide 2, a rectangular waveguide or probe (in FIG. 1, rectangular waveguide 6) provided as an output means of the electromagnetic wave introduced into the circular waveguide 2 is formed. By setting the value of the DC magnetic field of the ferrite rod 5 within the Faraday rotation region, the horizontal polarized wave or the vertical polarized wave introduced into the circular waveguide 2,
By selecting the polarization signal desired to be received and outputting it from the output means (the rectangular waveguide 6 in FIG. 1), and setting the value of the DC magnetic field of the ferrite rod 5 within the magnetic resonance region, One of the right-handed or left-handed circularly polarized waves introduced into the circular waveguide 2 is absorbed by the magnetic resonance phenomenon of the right-handed circularly polarized wave, and the other one desired to be received becomes the negatively circularly polarized wave. The output means (the rectangular waveguide 6 in FIG. 1) is used for output.

[0005]

According to the invention, one primary radiator located at the focal point of the reflector is used to direct the reflector towards the communication satellite when receiving the CS, with the vertical radiator introduced in the same primary radiator. And select the desired one from the horizontal polarization, output it as a signal and input it to the converter, when receiving the BS, turn the reflector toward the broadcasting satellite,
The satellite is selected by selecting the desired one from the right-handed and left-handed circularly polarized waves introduced in the same primary radiator, outputting it as a signal, inputting it to the converter, and changing the local oscillation frequency with this converter to select the satellite. It is possible to receive broadcast or radio waves from communication satellites. FIG. 3 is an explanatory view of the microwave permeability characteristics of the ferrite rod 5 used in the circular waveguide of the primary radiator of the present invention, and the horizontal axis Hdc is the ferrite rod using the exciting coil 4 shown in FIG. 5 shows the value of the DC magnetic field applied to No. 5, and the vertical axis shows the following magnitude. μ1 ′ is the real part of the permeability of the right circular polarization μ2 ′ is the real part of the permeability of the negative circular polarization μ1 ″ is the imaginary part of the permeability of the right circular polarization In addition, is the Faraday rotation region, and is , Μ1 ′
Indicates a region in the vicinity of zero magnetic permeability, indicates a resonance phenomenon region of circularly polarized wave, and Ho indicates the strength of the DC magnetic field at the resonance point.

FIG. 4 is an explanatory view of the Faraday rotation of a circular waveguide loaded with a ferrite rod 5, in which linearly polarized light is incident from the opening 1 of the circular waveguide 2 in the direction of an electric field directed in the vertical direction. , The ferrite rod 5 in the direction of electromagnetic wave propagation
It is assumed that a DC magnetic field Hdc is applied to. The linearly polarized wave can be decomposed into two circularly polarized waves, clockwise and counterclockwise. If the clockwise direction is positive and the counterclockwise direction is negative with respect to the propagation direction of the radio wave, the ferrite is as shown in FIG. The magnetic permeability of the rod 5 is different between μ1 'and μ for circularly polarized waves and negatively polarized waves.
2 ', and the phase constants for the circularly polarized wave and the negatively polarized wave also have different values of β1 and β2. Ferrite rod 5
Is L, the spatial phase angle of the linearly polarized wave at the place where the linearly polarized wave passes through the ferrite rod 5 is Θ = L (β2-β1) / 2 with respect to the incident state. ───── (1) Rotate only.

When receiving CS, a desired one is selected for the horizontal polarization or the vertical polarization introduced into the circular waveguide 2 shown in FIG. 1, and the selected polarization is selected from the rectangular waveguide 6. The current flowing through the exciting coil 4 is controlled so that the wave becomes maximum, and the DC magnetic field applied to the ferrite rod 5 is adjusted within the Faraday rotation region shown in FIG. The electric field distribution of horizontal polarization or vertical polarization introduced into the circular waveguide 2 is
Since the TE11 mode linearly polarized waves are orthogonal to each other and the phase angle is relatively rotated by the ferrite rod 5 by the equation (1), if one is set to be output from the rectangular waveguide 6, the other is No output. Therefore, only the signal desired to be received can be taken out from the rectangular waveguide 6 and input to the converter.

When the BS is received and the desired reception is a right-handed circularly polarized wave, a right-handed circularly polarized wave out of the right-handed circularly polarized wave or the left-handed circularly polarized wave introduced into the circular waveguide 2. However, the direction of the DC magnetic field applied to the ferrite rod 5 is set so that a negative circular polarization is obtained. By doing this, the unnecessary left-handed circularly polarized wave becomes a positive circularly polarized wave. The DC magnetic field applied to the ferrite rod 5 is shown in FIG.
By setting the strength of the DC magnetic field at the resonance point of Ho as shown by, when the right-handed circularly polarized wave and the left-handed circularly polarized wave pass through the loading part of the ferrite rod 5, unnecessary left-handed circularly polarized waves are absorbed by the magnetic resonance phenomenon. Then, only the right-handed circularly polarized wave desired to be received passes through the loaded portion of the ferrite rod 5. Regarding the right-handed circularly polarized wave desired to be received, only one of the linearly polarized waves orthogonal to the circularly polarized wave is taken out as a signal from the rectangular waveguide 6 and input to the converter. About 3db
However, since the BS radio waves are stronger than the CS radio waves, the BS radio waves can be received by using a large reflector that can receive the CS radio waves as an antenna.

When receiving a left-handed circularly polarized wave, the direction of the DC magnetic field applied to the ferrite rod 5 is set so that the desired left-handed circularly polarized wave becomes a negative circularly polarized wave. If you do this,
Unnecessary right-handed circular polarization becomes positive circular polarization. Ferrite rod 5
By setting the DC magnetic field to be added to the strength of the DC magnetic field at the resonance point of Ho shown in FIG. 3, when the right-handed circular polarization and the left-handed circular polarization pass through the loading portion of the ferrite rod 5, unnecessary right-handed circular The polarized wave is absorbed by the magnetic resonance phenomenon, and only the left-handed circularly polarized wave desired to be received passes through the loaded portion of the ferrite rod 5. Therefore, it becomes possible to extract only one of the left-handed circularly polarized linearly polarized waves as a signal from the rectangular waveguide 6 and input it to the converter.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization showing an embodiment of the present invention, and FIG. 2 is a front view of FIG. In the figure, the axis extending in the direction perpendicular to the tube axis of the circular waveguide 2 is the Y axis, and the axis extending in the horizontal direction is the X axis [hereinafter, FIG. 4, FIG. 5 (A) and (B)]. , FIG. 6 (A) and (B), FIG. 7, FIG. 8 (A) and (B)]. One end of the circular waveguide 2 has a horn-shaped opening 1 so that electromagnetic waves can be efficiently introduced, and a terminal surface 3 for reflecting the introduced electromagnetic waves is provided at the other end. On the part 1 side, a ferrite rod 5 is arranged at the center of the circular waveguide 2 so that the longitudinal direction is parallel to the tube axis. The exciting coil 4 is directly wound around the ferrite rod 5 so that a direct magnetic field can be applied to the ferrite rod 5.
The exciting coil 4 is held inside the circular waveguide 2 by using an adhesive or the like. The exciting coil 4 may be wound around the outer side surface of the circular waveguide 2 in which the ferrite rod 5 is located and used to apply a DC magnetic field to the ferrite rod 5, instead of being wound directly around the ferrite rod 5. In this case, a dielectric material is used so that the ferrite rod 5 can be held at the center of the circular waveguide 2.

If the diameter of the ferrite rod 5 is increased,
The length to obtain the required rotation angle of the electromagnetic wave becomes shorter,
If the diameter is made smaller, the length for obtaining the necessary rotation angle of the electromagnetic wave becomes longer, but the one having an appropriate diameter is selected and used so that it can be arranged inside the circular waveguide 2. A rectangular waveguide 6 is joined to the side surface of the circular waveguide 2 on the side of the end surface 3 as an output means of the electromagnetic wave introduced into the circular waveguide 2, and the tube axis of the rectangular waveguide 6 is extended. The line and the tube axis of the circular waveguide 2 are arranged to be orthogonal to each other, and the circular waveguide 2 and the rectangular waveguide 6 are connected through an opening 7 so that electromagnetic waves can be output from the rectangular waveguide 6. ing. The lead wire 8 of the exciting coil 4 provided in the circular waveguide 2 is drawn out of the circular waveguide 2 through an opening 9 provided on the side surface of the circular waveguide 2 and connected to a DC power source. A direct current is passed through the exciting coil 4 so that a predetermined DC magnetic field can be applied to the ferrite rod 5.

When receiving the horizontal polarization or the vertical polarization from the communication satellite, by adjusting the direct current flowing through the exciting coil 4 and setting the value of the direct magnetic field applied to the ferrite rod 5 within the Faraday rotation region. Of the horizontal polarization or the vertical polarization introduced in the circular waveguide 2, the rectangular waveguide 6
The polarization signal desired to be received from the receiver is maximized so that the same output is input to the converter to receive the communication satellite. When receiving satellite broadcasting, by adjusting the DC current flowing through the exciting coil 4 and setting the value of the DC magnetic field applied to the ferrite rod 5 within the magnetic resonance region,
The right-handed or left-handed circularly polarized wave from the satellite introduced into the circular waveguide 2 is absorbed by the magnetic resonance phenomenon of the circularly polarized wave, and the other desired reception becomes the circularly polarized wave. Thus, the polarized wave signal desired to be received is output from the rectangular waveguide 6, and the output is input to the converter to receive the satellite broadcast.

FIG. 5A is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization showing another embodiment of the present invention, and FIG. 5B is a front view of the same. . A rectangular waveguide 6 is joined to the side surface of the circular waveguide 2 on the side of the end surface 3 as an output means of the electromagnetic wave introduced into the circular waveguide 2, and the tube axis of the rectangular waveguide 6 is extended. The line and the tube axis of the circular waveguide 2 are arranged to be orthogonal to each other, and the circular waveguide 2 and the rectangular waveguide 6 are connected through an opening 7 so that electromagnetic waves can be output from the rectangular waveguide 6. ing. A substantially rectangular resistance plate 10 is provided between the junction of the rectangular waveguide 6 and the end surface 3 of the circular waveguide 2, and the short side of the resistance plate 10 is oriented perpendicular to the end surface 3 to form a square shape. The resistance plate 10 is arranged in a direction in which the long side direction of the waveguide 6 is parallel to the extension line of the waveguide axis so that the unwanted mode is attenuated by the resistance plate 10 with respect to a signal desired to be received. .

FIG. 6 (A) is a partially cutaway perspective view of a circularly-polarized and linearly-polarized primary radiator showing another embodiment of the present invention, and FIG. 6 (B) is a front view of the same. . Figure 5
The difference from the embodiments shown in (A) and (B) is that a substantially rectangular metal plate 11 is used in place of the resistance plate 10 used for attenuating unnecessary modes for a signal desired to be received. That is, it is arranged between the junction of the rectangular waveguide 6 and the ferrite rod 5. In the metal plate 11, the short side of the metal plate 11 is oriented parallel to the tube axis of the circular waveguide 2, and the long side of the metal plate 11 is an extension line of the tube axis of the rectangular waveguide 6. They are arranged in parallel to each other so that electromagnetic waves in unnecessary modes are reflected and only signals desired to be received are output from the rectangular waveguide 6.

FIG. 7 shows another embodiment of the present invention,
FIG. 2 is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization, which is different from the embodiment of FIG. 1 in that a rectangular waveguide is used as an output means of an electromagnetic wave introduced into a circular waveguide 2. Instead of joining the tube 6 to the side of the circular waveguide 2, a rectangular waveguide 13
Is joined to the outside of the end surface 3 of the circular waveguide 2, and is arranged so that the tube axis of the rectangular waveguide 13 and the extension line of the tube axis of the circular waveguide 2 overlap. The rectangular waveguide 13 and the circular waveguide 2 are connected via the slit 12. The shape of the slit 12 is a length of about a half wavelength of the electromagnetic wave output in the longitudinal direction, and the width of the slit 12 is such that the electric field of the electromagnetic wave in the unnecessary mode orthogonal to the desired signal does not pass through the slit 12. I am trying. Slit 1 so that the longitudinal direction of slit 12 is parallel to the Y axis
When 2 is arranged, the rectangular waveguide 13 is joined to the circular waveguide 2 such that the longitudinal direction of the cross section of the rectangular waveguide 13 is parallel to the Y axis. If the longitudinal direction of the slit 12 and the longitudinal direction of the cross section of the rectangular waveguide 13 are parallel to each other, the longitudinal direction of the slit 12 may be provided in another direction.

FIG. 8 (A) is a partially cutaway perspective view of a circularly-polarized and linearly-polarized primary radiator showing another embodiment of the present invention, and FIG. 8 (B) is a front view of the same. The difference from the embodiment of FIG. 1 is that instead of joining the rectangular waveguide 6 to the side surface of the circular waveguide 2, the probe 14 is used as an output means of the electromagnetic wave introduced into the circular waveguide 2. The extension line of the central axis of the probe 14 and the tube axis of the circular waveguide 2 are orthogonal to each other, and the probe 14 is inserted into the circular waveguide 2 from the outer side surface. The probe 14 is fixed to the side surface of the circular waveguide 2 by using the fixture 15, and the electromagnetic wave desired to be received introduced into the circular waveguide 2 is introduced into the portion of the probe 14 inserted into the circular waveguide 2. The probes 14 are coupled to each other and are output to the outside of the circular waveguide 2 by the probe 14 as an electric signal. The insertion depth of the probe 14 into the circular waveguide 2 is adjusted so that the signal extracted by the probe 14 becomes maximum. When the resistance plate 10 and the metal plate 11 shown in FIGS. 5 and 6 are used, the resistance plate 10 is extended with respect to the extension line of the central axis of the probe 14 as viewed from the opening 1 of the circular waveguide 2.
Is arranged such that the long sides of the resistance plate 10 are orthogonal to each other, or when the metal plate 11 is used, the long sides of the metal plate 11 are arranged to be orthogonal to each other, and the signal desired to be received is received. The unwanted mode signal may not be coupled to the probe 14.

[0017]

As described above, according to the present invention, B
The primary radiators for both circular polarization and linear polarization that are shared for S and CS are used, and the same primary radiator is placed at the focal point of the reflector, and the direction of the reflector is the direction of the broadcasting satellite when receiving BS. In the case of CS reception, BS and CS can be received in the direction of the communication satellite. As in the conventional case, the BS primary radiator and the CS primary radiator are mounted side by side on the same reflector, It is possible to provide an economical receiving system which has a simple structure and is cheaper than the one which receives radio waves and CS radio waves.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization, showing an embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is an explanatory diagram of microwave magnetic permeability characteristics of a ferrite rod.

FIG. 4 is an explanatory diagram of Faraday rotation of a circular waveguide loaded with a ferrite rod.

FIG. 5 (A) is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization showing another embodiment of the present invention, and FIG. 5 (B) is a front view of the same.

FIG. 6 (A) is a partially cutaway perspective view of a circularly-polarized and linearly-polarized primary radiator showing another embodiment of the present invention, and FIG. 6 (B) is a front view of the same.

FIG. 7 is a partially cutaway perspective view of a primary radiator for both circular polarization and linear polarization, showing another embodiment of the present invention.

FIG. 8A is a partially cutaway perspective view of a primary radiator for both circularly polarized waves and linearly polarized waves showing another embodiment of the present invention, and FIG. 8B is a front view of the same.

9A and 9B are explanatory views showing the arrangement of a reflector and a primary radiator, FIG. 9A showing a conventional example, and FIG. 9B showing an embodiment of the present invention.

[Explanation of symbols]

 1 Opening 2 Circular Waveguide 3 End Surface 4 Excitation Coil 5 Ferrite Rod 6 Rectangular Waveguide 7 Opening 8 Leader Line 9 Opening 10 Resistor Plate 11 Metal Plate 12 Slit 13 Square Waveguide 14 Probe 15 Fixture 16 Reflector 17 Primary radiator 18 Primary radiator 19 Reflector 20 Primary radiator 25 Notched line 26 Notched line 27 Notched line 28 Notched line 29 Notched line 30 Notched line 31 Notched line 31

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[Procedure amendment]

[Submission date] April 27, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

5A and 5B are explanatory views according to the present invention, in which FIG. 5A is a partially cutaway perspective view of a circularly-polarized and linearly-polarized primary radiator showing another embodiment of the present invention, and FIG. Is a front view of the above.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 6

[Correction method] Change

[Correction content]

6A and 6B are explanatory views according to the present invention, in which FIG. 6A is a partially cutaway perspective view of a primary radiator for circular polarization and linear polarization, showing another embodiment of the present invention; Is a front view of the above.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] Figure 8

[Correction method] Change

[Correction content]

8A and 8B are explanatory views according to the present invention, in which FIG. 8A is a partially cutaway perspective view of a circularly-polarized and linearly-polarized primary radiator showing another embodiment of the present invention; Is a front view of the above.

[Procedure amendment 4]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 6

[Correction method] Change

[Correction content]

[Figure 6]

[Procedure correction 6]

[Document name to be corrected] Drawing

[Correction target item name] Figure 8

[Correction method] Change

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[Figure 8]

Claims (7)

[Claims] 1. An opening for introducing an electromagnetic wave is provided at one end,
A circular waveguide with a terminating surface at the other end, and a ferrite rod placed at the center of the circular waveguide on the opening side inside the circular waveguide with its longitudinal direction parallel to the tube axis. And an exciting coil that is wound directly around the ferrite rod to apply a DC magnetic field to the ferrite rod, and a rectangular waveguide provided on the end face side of the circular waveguide as an output means of electromagnetic waves introduced into the circular waveguide. It consists of a tube or a probe, and by setting the value of the DC magnetic field of the ferrite rod within the Faraday rotation region, the desired polarization signal of the horizontal polarization or the vertical polarization introduced into the circular waveguide is obtained. To output from the output means, by setting the value of the DC magnetic field of the ferrite rod in the magnetic resonance region, of the right-handed or left-handed circularly polarized wave introduced into the circular waveguide, one of Is a circularly polarized magnetic Absorbed by phenomenon, circular polarization and linear polarization shared primary radiators, characterized in that allowed to output from said output means as the other desired received a negative circularly polarized wave. 2. The rectangular waveguide is joined to the side surface of the circular waveguide so that the extension line of the tubular axis of the rectangular waveguide and the tube axis of the circular waveguide are orthogonal to each other, and A substantially rectangular resistance plate is provided between the junction part of the waveguide and the end face of the circular waveguide, and the short side of the resistance plate is oriented perpendicular to the end face, and the rectangular waveguide 2. The resistor plate is arranged in a direction in which a long side direction of the resistor plate is parallel to an extension line of the tube axis, and an unnecessary mode is attenuated by the resistor plate with respect to a signal desired to be received. Primary radiator for both circular and linear polarization. 3. The probe is provided on the side surface of the circular waveguide so that the extension line of the central axis of the probe and the tube axis of the circular waveguide are orthogonal to each other, and the circular guide and the circular guide are provided. A substantially rectangular resistance plate is provided between the end faces of the wave tube, the short side of the resistance plate is oriented perpendicular to the end face, and the length of the resistance plate is long with respect to the extension line of the central axis of the probe. The primary radiator for both circularly polarized waves and linearly polarized waves according to claim 1, characterized in that the resistance plates attenuate the unwanted modes with respect to a signal desired to be received by arranging the sides in directions orthogonal to each other. 4. The rectangular waveguide is joined to the side surface of the circular waveguide so that the extension line of the tubular axis of the rectangular waveguide is orthogonal to the tube axis of the circular waveguide, and the rectangular waveguide is bonded to the side surface of the circular waveguide. A substantially rectangular metal plate is provided between the waveguide joint and the ferrite rod, the short side of the metal plate is oriented parallel to the tube axis of the circular waveguide, and the long side of the metal plate is 2. The circle according to claim 1, wherein the rectangular waveguide is arranged in a direction parallel to the extension line of the tube axis, and an unwanted mode is attenuated by the metal plate with respect to a signal desired to be received. Primary radiator for both polarized and linear polarization. 5. The probe is provided on a side surface of the circular waveguide so that an extension line of a central axis of the probe and a tube axis of the circular waveguide are orthogonal to each other, and a mounting portion of the probe and the ferrite rod are provided. A substantially rectangular metal plate is provided between them, and the short side of the metal plate is oriented parallel to the tube axis of the circular waveguide,
The long side of the metal plate viewed from the opening of the circular waveguide is arranged in a direction orthogonal to the extension line of the central axis of the probe, and an unnecessary mode is received by the metal plate for a signal desired to be received. The primary radiator for dual use of circular polarization and linear polarization according to claim 1, which is attenuated. 6. The rectangular waveguide is joined to the outside of the end surface of the circular waveguide, and is arranged so that the tube axis of the rectangular waveguide and the tube axis of the circular waveguide overlap each other. The primary radiator for dual-purpose circular polarization and linear polarization according to claim 1, wherein the rectangular waveguide and the circular waveguide are coupled by a slit. 7. The circularly polarized wave and linear polarization according to claim 1, wherein the exciting coil is wound around an outer side surface of the circular waveguide in which the ferrite rod is located, instead of directly winding around the ferrite rod. Wave primary radiator.