JPH05110302A - Primary radiator in common use for circularily polarized wave and linearly polarized wave - Google Patents

Abstract

PURPOSE:To provide the primary radiator able to receive both radio waves from a satellite employing a circularity polarized wave (rightand left-handed circularly polarized waves) and a linearly polarized wave (horizontal and vertical polarized waves). CONSTITUTION:The primary radiator is provided with a ferrite rod 5 arranged in the center of a circular waveguide 2 in a way that its lengthwise direction is in parallel with a guide axis to an opening 1 in the inside of the circular waveguide 2, an exciting coil 4 applying a DC magnetic field to the ferrite rod 5, an output means provided toward a termination face 3 in a way of outputting horizontal and vertical direction components in the TE11 mode of an electromagnetic wave, and square waveguides 6, 7, and a desired reception signal is obtained from one of the output means out of a horizontal polarized wave or a vertical polarized wave by setting a DC magnetic field in the ferrite rod 5 to be a strength in the Farady rotation region, and a desired reception signal is obtained from the other output means by setting a DC magnetic field in the ferrite rod 5 to be a strength in the magnetic resonance region so as to absorb either the right- or the left-handed circularly polarized wave through the magnetic resonance for the circularly polarized wave thereby obtaining the other of the reception desired waves as 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. 8 (A), a conventional BS and CS common antenna is provided with a BS primary radiator 17 and a CS primary radiator 18 mounted side by side on the same reflector 16 so that the reflector 16 has a focal point. 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 is different from that of each satellite. 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 focal points of 6 are deviated, and the structure is 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 radio wave and the CS radio wave can be received by the same primary radiator 20, and 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 circular polarization and linear polarization, 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 in the center of the circular waveguide 2 with its longitudinal direction parallel to the tube axis; an exciting coil 4 wound directly around the ferrite rod 5 to apply a DC magnetic field to the ferrite rod 5; Two output means (in FIG. 1, in FIG. 1) are provided on the end face 3 side of the circular waveguide 2 so as to output the horizontal and vertical components of the TE11 mode of the electromagnetic wave propagating in the circular waveguide 2. Rectangular waveguides 6 and 7), by setting the value of the DC magnetic field of the ferrite rod 5 within the Faraday rotation region, the horizontal polarization or vertical polarization of the circular waveguide 2 Among them, a polarized wave signal desired to be received is selected and output from one of the output means, and the direct current magnetic field of the ferrite rod 5 is set in the magnetic resonance region to be introduced into the circular waveguide 2. Right turn or One of the circularly polarized waves is absorbed by the magnetic resonance phenomenon of the circularly polarized wave, and the other desired reception is made to be the negative circularly polarized wave so that the other one of the output means outputs it. ..

[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 and to introduce a vertical radiator into the same primary radiator. And a desired one from the horizontally polarized waves, and outputs it as a signal from one of the output means provided in the same primary radiator, inputs it to the CS converter, and when receiving BS, directs the reflector toward the broadcasting satellite, A desired one is selected from right-handed and left-handed circularly polarized waves introduced into the same-order radiator, and is output as a signal from the other of the output means provided in the same-order radiator to be input to the BS converter. Then, by changing the local oscillation frequency, the CS converter converts the input signal into a CS-IF signal, the BS converter converts the input signal into a BS-IF signal, and each is converted into a satellite broadcast receiver. By entering, so that it is possible to receive the radio wave of the communication satellite or satellite.

FIG. 3 is an explanatory view of the microwave permeability characteristics of the ferrite rod used in the circular waveguide of the primary radiator of the present invention. The horizontal axis Hdc is the excitation coil 4 shown in FIG. The value of the DC magnetic field applied to the ferrite rod 5 is shown, 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 Further, is the Faraday rotation region, , Μ1 ′
Indicates a region near 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, 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, It is assumed that a DC magnetic field Hdc is applied to the ferrite rod 5 in the electromagnetic wave propagation direction. Linearly polarized light 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,
As shown in FIG. 3, the magnetic permeability of the ferrite rod 5 is different between μ1 ′ and μ2 ′ for the right circular polarization and the right circular polarization.
Therefore, the phase constants for the circularly polarized wave and the negatively polarized wave also have different values, β1 and β2, respectively. Letting the length of the ferrite rod be L, where the linearly polarized wave passes through the ferrite rod, the spatial phase angle of the linearly polarized wave is Θ = L (β2-β1) / 2 ───── (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 distributions of the horizontal polarization and the vertical polarization introduced into the circular waveguide 2 are TE11 mode linear polarizations orthogonal to each other, and the phase angle is relatively rotated by the ferrite rod 5 by the equation (1). Therefore, if one is set to output from the rectangular waveguide 6, the other is output from the rectangular waveguide 7.

When the BS is received and the desired reception is right-handed circular polarization, the right-handed circular polarization out of the right-handed circular polarization or the left-handed circular polarization introduced into the circular waveguide 2. , The direction of the DC magnetic field applied to the ferrite rod 5 is set so that the circularly polarized wave becomes negative. By doing so, 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 shown in, when the right-handed circularly polarized wave and the left-handed circularly polarized wave pass through the loading portion 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. Therefore, only right-handed circularly polarized waves propagate to the junction of the rectangular waveguides 6 and 7.

When receiving the 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 the 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 applied to the strength of the DC magnetic field at the resonance point of Ho shown in FIG. 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, unlike the above, only left-handed circularly polarized waves propagate to the junction of the rectangular waveguides 6 and 7.

Regarding the circularly polarized wave desired to be received, if one of the linearly polarized waves orthogonal to the circularly polarized wave is set to be output as a signal from the rectangular waveguide 7, the other is output from the rectangular waveguide 6. To be done. For example, if the CS converter is connected to the tip of the rectangular waveguide 6 and the BS converter is connected to the tip of the rectangular waveguide 7, the CS converter and the BS converter are each a local part for converting into an IF signal. Since the oscillation frequencies are different, the CS converter tunes only the input CS signal, and the BS converter tunes only the input BS signal to perform signal processing respectively.
Alternatively, it becomes possible to receive satellite broadcast radio waves.
When receiving satellite broadcasting, only one of the linearly polarized waves that are orthogonal to the circularly polarized wave is received, so the received signal level is attenuated by about 3 db, but the received signal level is B for CS radio waves.
Since the S radio wave is strong, if a large reflector that can receive the CS radio wave is used as an antenna, the BS radio wave can be received.

[0012]

1 is a partially cutaway perspective view of a primary radiator for 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 defined as the Y axis, and the axis extending in the horizontal direction is defined as the X axis [hereinafter, in FIGS. 4, 5, 6, and 7]. the same〕. One end of the circular waveguide 2 is formed as 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 side of the portion 1, a ferrite rod 5 is arranged in 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-current magnetic field can be applied to the ferrite rod 5. The exciting coil 4 uses an adhesive agent or the like to provide a predetermined inside of the circular waveguide 2. I try to keep it in position. Instead of winding the exciting coil 4 directly on the ferrite rod 5, the exciting coil 4 is wound around the outer side surface of the circular waveguide 2 where the ferrite rod 5 is located,
A DC magnetic field may be applied to the ferrite rod 5.
In this case, use a dielectric material to
Can be held at the center of the circular waveguide 2. If the diameter of the ferrite rod 5 is increased, the length for obtaining the required rotation angle of the electromagnetic wave is shortened, and if the diameter is reduced, the length for obtaining the required rotation angle of the electromagnetic wave is increased. An appropriate diameter is selected and used so that it can be placed inside the wave tube 2.

The rectangular waveguides 6 and 7 capable of outputting the horizontal and vertical components of the TE11 mode of the electromagnetic wave propagating in the circular waveguide 2 to the side surface of the circular waveguide 2 on the side of the termination surface 3. Are arranged so that the extension lines of the tube axes of the rectangular waveguides 6 and 7 and the tube axis of the circular waveguide 2 are orthogonal to each other, and the extension line of the tube axis of the rectangular waveguide 6 and the rectangle Waveguide 7
The extension lines of the tube axes are also arranged so as to be orthogonal to each other, the circular waveguide 2 and the rectangular waveguide 6 are connected through the opening 9, and the circular waveguide 2 and the rectangular waveguide 7 are connected through the opening 10. , And the electromagnetic waves can be output from the rectangular waveguide 6 and the rectangular waveguide 7. The lead wire 8 of the exciting coil 4 provided in the circular waveguide 2 is drawn to the outside of the circular waveguide 2 through an opening 11 provided on the side surface of the circular waveguide 2 and connected to a DC power source. , Applying a direct current to the exciting coil 4,
A predetermined DC magnetic field can be applied to the ferrite rod 5.

For example, assume that a CS converter is connected to the tip of the rectangular waveguide 6 and a BS converter is connected to the tip of the rectangular waveguide 7. When receiving horizontal polarization or vertical polarization from the communication satellite, adjust the DC current flowing through the exciting coil 4 and set the value of the DC magnetic field applied to the ferrite rod 5 within the Faraday rotation region to obtain a circular guide. The horizontal polarization or the vertical polarization introduced into the wave tube 2 is input to the CS converter so that the desired polarization signal output from the rectangular waveguide 6 is maximized, and communication is performed. I am trying to receive satellites. When receiving satellite broadcasting, adjust the direct current flowing through the exciting coil 4 to
By setting the value of the DC magnetic field applied to the magnetic resonance region within the magnetic resonance region, one of the right-handed circular polarization or the left-handed circularly polarized wave from the satellite introduced into the circular waveguide 2 is a circularly polarized magnetic resonance. It is absorbed by the phenomenon so that the other desired reception is made into a negative circular polarization, the polarized signal desired to be received is output from the rectangular waveguide 7, and the same output is input to the BS converter. I try to receive the broadcast.

FIG. 5 is a partially cutaway perspective view of a circularly polarized wave and linearly polarized wave primary radiator showing another embodiment of the present invention, and FIG. 6 is a circular waveguide 2 shown in FIG. The cutting line ab
Sectional drawing cut by. Two output means capable of outputting the horizontal direction component and the vertical direction component of the TE11 mode of the electromagnetic wave propagating in the circular waveguide 2 are arranged in order toward the terminal face, and one of the output means is provided. Similar to the embodiment shown in FIG. 1, the rectangular waveguide 7 is used to take out the output, and the other of the output means is attached to the circular waveguide 2 as seen from the opening 1 side of the circular waveguide 2. The angle of the rectangular waveguide 1 is made equal to that of the rectangular waveguide 1.
2 is mounted, and the mounting position when viewed from the side surface of the circular waveguide 2 is between the rectangular waveguide 7 and the end surface 3. In the case of the embodiment shown in FIG. 1, the two output means are attached in a direction intersecting with each other at a position substantially the same distance from the end face 3 of the circular waveguide 2 to shorten the length of the circular waveguide 2. In the case of the embodiment shown in FIG. 5, the two output means are joined to the circular waveguide 2 from the same direction, which makes it easier to handle the primary radiator during processing or mounting on the reflector. ..

The rectangular waveguide 12 and the circular waveguide 2 are connected by using a probe 13, and the mounting position of the probe 13 from the end surface 3 as seen from the side surface of the circular waveguide 2 is as follows.
The length of the electromagnetic wave coupled to the probe 13 is about ¼ wavelength, and the insertion depth of the probe 13 into the circular waveguide 2 is determined by adjusting so that the electromagnetic wave can be efficiently coupled to the probe 13. The probe 13 converts an electromagnetic wave into an electric signal and transmits the electric signal to the inside of the rectangular waveguide 12, and the rectangular waveguide 1
Electromagnetic waves are excited at the bent portion of the tip inserted in 2. The depth of insertion of the probe 13 into the rectangular waveguide 12 is about 1/4 wavelength of the electromagnetic wave excited by the probe 13, and the probe 13 is a fixture using an insulator on the side surface of the circular waveguide 2. Holds at 14.

A substantially rectangular metal plate 15 is provided inside the circular waveguide 2 between the mounting portions of the rectangular waveguide 7 and the probe 13, and the short side of the metal plate 15 is used as the tube axis of the circular waveguide 2. With the rectangular waveguide 7, the long side of the metal plate 15 viewed from the opening 1 of the circular waveguide 2 is arranged in a direction orthogonal to the extension line of the central axis of the probe 13, The horizontal component of the TE11 mode of an electromagnetic wave having an electric field in the direction parallel to the X axis is output, and the horizontal component is reflected by the metal plate 15 so that the horizontal component does not face the probe 13, and Y
The vertical component of the TE11 mode of the electromagnetic wave having the electric field in the direction parallel to the axis is coupled to the probe 13, and only the unnecessary mode for the probe 13 is attenuated by the metal plate 15.

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. The difference from the embodiment shown in FIG. The length of the wave guide 2 is extended, the rectangular waveguide 6 is shifted to the end face 3 side and joined to the side surface of the circular waveguide 2, and the rectangular waveguide 7 and the rectangular waveguide 6 are joined to each other. A substantially rectangular metal plate 15 is provided inside the circular waveguide 2, and the short side of the metal plate 15 is oriented parallel to the tube axis of the circular waveguide 2, and the opening of the circular waveguide 2 is formed. 1
The long side of the metal plate 15 when viewed is arranged in a direction parallel to the extension line of the tube axis of the rectangular waveguide 6, and in the rectangular waveguide 7, the TE11 mode of the electromagnetic wave having the electric field is oriented in the direction parallel to the X axis. The horizontal component is output, the horizontal component is reflected by the metal plate 15 so that the horizontal component does not face the rectangular waveguide 6, and the TE of the electromagnetic wave having the electric field in the direction parallel to the Y axis is output.
The 11-mode vertical component is output by the rectangular waveguide 6, and only the unnecessary mode for the rectangular waveguide 6 is attenuated by the metal plate 15.

[0019]

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 having a simpler structure and lower cost than the one that 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 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. 6 shows a cross-sectional view of FIG. 5 taken along the cutting line ab.

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. 8 is an explanatory view showing the arrangement of a reflector and a primary radiator, (A) showing a conventional example, and (B) showing an embodiment of the present invention.

[Explanation of symbols]

 1 Opening 2 Circular Waveguide 3 End Face 4 Excitation Coil 5 Ferrite Rod 6 Rectangular Waveguide 7 Rectangular Waveguide 8 Leader Line 9 Opening 10 Opening 11 Opening 12 Rectangular Waveguide 13 Probe 14 Fixture 15 Metal Plate 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

Claims (4)

[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 the 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 the horizontal direction component and vertical direction of the TE11 mode of the electromagnetic wave propagating in the circular waveguide on the end face side of the circular waveguide. And a horizontal polarization or a vertical polarization introduced into the circular waveguide by setting the value of the DC magnetic field of the ferrite rod within the Faraday rotation region. Of the desired polarization signal to be received and output from one of the output means, and the direct current magnetic field of the ferrite rod is set to a value within the magnetic resonance region so that it is introduced into the circular waveguide. Right turn One of the left-handed circularly polarized waves is absorbed by the magnetic resonance phenomenon of the right-handed circularly polarized wave, and the other desired reception is made a negative circularly polarized wave, and is output from the other of the output means. Primary radiator for both polarized and linear polarization. 2. The primary radiation for both circularly polarized light and linearly polarized light according to claim 1, wherein the two output means are two rectangular waveguides or probes, or a combination of both. vessel. 3. The two output means are arranged side by side toward the end face of the circular waveguide, and a substantially rectangular metal plate is provided inside the circular waveguide between the mounting portions of the both output means. When the short side of the metal plate is oriented parallel to the tube axis of the circular waveguide, and the output means provided on the end face side is a rectangular waveguide, the opening of the circular waveguide is used. When the long side of the viewed metal plate is arranged in a direction parallel to the extension line of the tube axis of the isotropic waveguide, and the output means provided on the end face side is a probe, a circular waveguide is used. The long side of the metal plate viewed from the opening of the probe is arranged in a direction orthogonal to the extension line of the central axis of the probe, and the unnecessary mode is set to the signal output by the output means provided on the end face side. The primary radiator for dual-use circular polarization and linear polarization according to claim 1, wherein the primary radiator is attenuated by a metal plate. 4. 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 where the ferrite rod is located, instead of directly winding around the ferrite rod. Wave primary radiator.