JPH0729917U - Primary radiator - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a primary radiator that can select and receive a desired polarization from horizontal polarization, vertical polarization, left-hand circular polarization, and right-hand circular polarization. The purpose is to [Structure] The circular waveguides 2 and 3 are concentrically connected by a ferrite rod 5, a probe 7 is provided as an output means of the radio wave introduced into the circular waveguide 3, and an exciting coil for applying a DC magnetic field to the ferrite rod 6 is provided and the DC magnetic field of the ferrite rod 5 is set to a predetermined value within the Faraday rotation region by controlling the DC magnetic field. Of the waves, the polarization signal desired to be received is selected and output from the probe 7, and the DC magnetic field applied to the ferrite rod is set to a predetermined value within the magnetic resonance region. One of the left-handed circularly polarized wave and the left-handed circularly polarized wave is absorbed by the magnetic resonance phenomenon, and only the circularly polarized wave desired to be received is passed and output from the probe 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention makes it possible to receive both circularly polarized waves using a right-handed and a left-handed circularly transmitted from a satellite and linearly-polarized waves using a horizontally-polarized wave and a vertically-polarized wave. Regarding the primary radiator.

[0002]

[Prior art]

 The conventional circular polarization and linear polarization dual-use antennas are equipped with a primary radiator for circular polarization and a primary radiator for linear polarization side by side on the same reflector, with the reflectors oriented in the direction of each satellite. It was designed to receive polarized waves and linearly polarized waves. With the increase in the number of channels for satellite broadcasting, plans are underway to provide broadcasting services using left-hand circular polarization and right-hand circular polarization in the same area. As a primary radiator for shared reception, there is a primary radiator as shown in FIG. 7 (A), which is rotatable around the tube axis of the circular waveguide 20 according to the circular polarization desired to be received. The circularly polarized wave is converted into a linear polarized wave by the dielectric plate 21 by rotating the dielectric plate 21 and the received signal is extracted by coupling the linear polarized wave with the probe 22. Further, as a primary radiator capable of receiving the horizontally polarized wave and the vertically polarized wave, there is a primary radiator as shown in FIG. 7B, and a probe 24 provided on the terminal surface 25 of the circular waveguide 20 is provided. Rotate so that the direction of the probe 24 is parallel to the direction of the electric field of the desired polarization of horizontal polarization and vertical polarization, and couple the linear polarization of the desired reception to the probe 24. The received signal is taken out through the rectangular waveguide 26.

[0003]

[Problems to be solved by the device]

 Therefore, since two primary radiators are attached to the same reflector, the mounting position of the primary radiator deviates from the focal point of the reflector, so that there is a problem that the gain obtained by the primary radiator decreases, and each primary radiator has a problem. There is also a problem in that the structure is complicated because the radiator is provided with a drive unit to rotate the dielectric plate and the probe. The present invention is a primary radiator with a simple structure and low cost, which can select and receive a desired polarization from horizontal polarization, vertical polarization, left-hand circular polarization, and right-hand circular polarization. The purpose is to provide.

[0004]

[Means for Solving the Problems]

 The first radiator of the first invention of the present application comprises a first circular waveguide having an opening for introducing radio waves at one end and a connecting end at the other end, and a terminal end surface at one end and a connecting end at the other end. The second circular waveguide, the ferrite rod fitted in each of the connection ends of the first and second circular waveguides and connected concentrically, and the direct current magnetic field is applied by winding around the ferrite rod. It is composed of an exciting coil and a rectangular waveguide provided as an output means of the radio wave introduced into the second circular waveguide, and sets the DC magnetic field of the ferrite rod to a predetermined value within the Faraday rotation region. As a result, the desired polarization signal can be selected from the horizontal polarization or the vertical polarization introduced into the first circular waveguide and output from the output means. The primary radiator of the second invention of the present application comprises a first circular waveguide having an opening for introducing radio waves at one end and a connecting end at the other end, and a terminal end surface at one end and a connecting end at the other end. The second circular waveguide, the ferrite rod fitted in each of the connection ends of the first and second circular waveguides and connected concentrically, and the direct current magnetic field is applied by winding around the ferrite rod. It consists of an exciting coil and a probe provided as an output means of the radio wave introduced into the second circular waveguide, and by setting the DC magnetic field of the ferrite rod to a predetermined value within the Faraday rotation region, It is characterized in that a polarization signal desired to be received is selected from the horizontally polarized waves or the vertically polarized waves introduced into the first circular waveguide and is output from the output means.

In the primary radiator of the third invention of the present application, by setting the direct-current magnetic field of the ferrite rod to a predetermined value in the magnetic resonance region, the right-handed rotor introduced in the first circular waveguide. Among the left-handed circularly polarized waves, one is absorbed by a magnetic resonance phenomenon and the other is allowed to pass therethrough, and a circularly polarized wave desired to be received is selected and output from the output means. A primary radiator according to a fourth aspect of the present invention has a substantially rectangular shape that passes through the tube axis of the second circular waveguide between the output means and the terminating surface and is perpendicular to the terminating surface. It is characterized in that a resistance plate is provided, the resistance plate is arranged so as to be parallel to the electric field direction of the cross polarization with respect to the polarization desired to be received, and the cross polarization is attenuated by the same resistance plate. The primary radiator of the fifth invention of the present application passes through the tube axis of the second circular waveguide between the ferrite rod and the output means and is parallel to the tube axis of the second circular waveguide. Provide a substantially rectangular metal plate in the opposite direction, arrange the metal plate so that it is parallel to the direction of the electric field of the cross-polarized wave with respect to the desired polarized wave, and attenuate the cross-polarized wave with the same metal plate. Is a feature.

[0006]

[Action]

 In the primary radiators of the first and second inventions of the present application, the horizontal or vertical polarization introduced into the circular waveguide is set by setting the DC magnetic field applied to the ferrite rod to a predetermined value within the Faraday rotation region. Since the direction of the electric field of can be relatively rotated by the ferrite rod, by controlling the DC magnetic field applied to the ferrite rod, only the signal desired to be received is selected and used as the output means. Or, it can be output from the probe. In the primary radiator of the third invention of the present application, right-handed circular polarization or left-handed circular polarization introduced into the circular waveguide is achieved by setting the DC magnetic field applied to the ferrite rod to a predetermined value within the magnetic resonance region. On the other hand, since one can be absorbed by the magnetic resonance phenomenon and only the other can be passed and output, by controlling the DC magnetic field applied to the ferrite rod, only the desired signal is selected and output from the output means. It is possible to output.

In the primary radiator of the fourth invention of the present application, a substantially rectangular resistance plate is passed through the tube axis of the second circular waveguide between the output means and the above-mentioned termination surface, and is connected to the termination surface. The resistance plate is arranged in a direction perpendicular to the output means so that the arrangement of the resistance plate relative to the output means is parallel to the direction of the cross-polarized electric field with respect to the desired polarization output by the output means. By arranging them, cross-polarized waves are attenuated by the same resistance plate, and it becomes possible to select only the signal desired to be received and output it from the output means. In the primary radiator of the fifth invention of the present application, a substantially rectangular metal plate is passed through the tube axis of the second circular waveguide between the ferrite rod and the output means, and the second circular waveguide is provided. The orientation of the metal plate relative to the output means is parallel to the direction of the cross-polarized electric field with respect to the desired polarized wave output by the output means. By arranging so that the cross-polarized waves are attenuated by the same metal plate, it becomes possible to select only the signal desired to be received and output it from the output means.

[0008]

【Example】

 1A and 1B are explanatory views showing a first embodiment of the primary radiator of the present invention, FIG. 1A is a partially cutaway perspective view, and FIG. 1B is a front view. One end of the circular waveguide 2 is a horn-shaped opening 1 so that radio waves can be efficiently introduced, the other end is a connection end with a narrow inner diameter, and one end of the circular waveguide 3 is a termination surface 4, The ends of the ferrite rods 5 are fitted to the connection ends of the circular waveguides 2 and 3, respectively, with the ends being the connection ends with a thin inner diameter, so that the circular waveguides 2 and 3 and the ferrite rod 5 become concentric. Are connected. The exciting coil 6 is electrically insulated from the circular waveguides 2 and 3 and the ferrite rod 5 and wound around the ferrite rod 5, and a DC voltage is applied to the lead wire 9 of the exciting coil 6 to apply a direct current to the exciting coil 6. A DC magnetic field can be applied to the ferrite rod 5 by passing an electric current.

As the inner diameters of the circular waveguides 2 and 3, for example, those capable of propagating TE11 mode radio waves are selected, and similarly, the diameter of the ferrite rod 5 also propagates TE11 mode radio waves. The inner diameter of the connection end of the circular waveguides 2 and 3 is set to a diameter capable of holding the ferrite rod 5 from the outside. The probe 7 is inserted in a direction toward the axis of the circular waveguide 3 through a through hole 8 provided on the side surface of the circular waveguide 3, and couples the radio wave introduced into the circular waveguide 3 to the probe 7. I am able to do that. The probe 7 forms a coaxial line by insulating the wall surface of the through hole 8 with a dielectric, transmits the radio wave coupled to the probe 7 in the coaxial mode, inputs it to the converter, and receives the radio wave from the satellite. I am able to do it.

FIG. 2 is an explanatory diagram of the microwave permeability characteristics of the ferrite rod 5 used in the primary radiator of the present invention. The horizontal axis Hdc is the ferrite rod 5 using the exciting coil 6 shown in FIG. The value of the DC magnetic field applied to 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 In addition, is the Faraday rotation region, and is , Μ1 ′ in the vicinity of the zero magnetic permeability, represents the resonance phenomenon region of circularly polarized wave, and Ho represents the strength of the DC magnetic field at the resonance point.

FIG. 3 is an explanatory diagram of Faraday rotation of the ferrite rod 5, in which linearly polarized light is incident from the opening 1 of the circular waveguide 2 in the direction of the electric field directed in the vertical direction, and is propagated in the propagation direction of the radio wave. It is assumed that a DC magnetic field Hdc is applied to the ferrite rod 5 toward the front. 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, as shown in FIG. The magnetic permeability of the rod 5 has different values of μ1 ′ and μ2 ′ for the normal circular polarization and the negative circular polarization, respectively, so that the phase constants for the right circular polarization and the negative circular polarization also have different values, β1 and β2. Assuming that the length of the ferrite rod 5 is L, when the linearly polarized wave passes through the ferrite rod 5, the spatial phase angle of the linearly polarized wave is Θ = L (β2 -Β1) / 2 ────── Rotate by (1).

When receiving the linearly polarized wave, the desired one is selected for the horizontal polarized wave or the vertical polarized wave introduced into the circular waveguide 2 shown in FIG. 1, and the selection output from the probe 7 is selected. The current flowing through the exciting coil 6 is controlled so that the polarized wave obtained is maximized, 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 in the circular waveguide 2 is linear polarization orthogonal to each other, and the phase angle is relatively rotated by the ferrite rod 5 according to the equation (1). However, if one is set to be output from the probe 7, the other is not output. Therefore, only the signal desired to be received can be taken out from the probe 7 and input to the converter.

When receiving circularly polarized waves and the desired reception is right-handed circularly polarized waves, right-handed circularly polarized waves out of right-handed circularly polarized waves or left-handed circularly polarized waves introduced in the circular waveguide 2 are received. The direction of the DC magnetic field applied to the ferrite rod 5 is set so that the polarized wave becomes a negative circular polarized wave. In this way, the unwanted left-handed circularly polarized wave becomes a positive circularly polarized wave. By setting the DC magnetic field applied to the ferrite rod 5 to the strength of the DC magnetic field at the Ho resonance point shown in Fig. 2, when right-handed circular polarization and left-handed circular polarization pass through the ferrite rod 5, unnecessary left-handed The circularly polarized wave is absorbed by the magnetic resonance phenomenon, and only the right-handed circularly polarized wave desired to be received passes through the ferrite rod 5 and is output. The right-handed circularly polarized wave desired to be received is designed so that only one of the linearly polarized components orthogonal to the circularly polarized wave is coupled to the probe 7 and extracted as a signal to be input to the converter. However, if a large reflector antenna is used, circularly polarized radio waves can be received.

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. In this way, the unnecessary right-handed circularly polarized wave becomes positive circularly polarized wave. By setting the DC magnetic field applied to the ferrite rod 5 to the strength of the DC magnetic field at the Ho resonance point shown in Fig. 2, when right-handed circular polarization and left-handed circular polarization pass through the ferrite rod 5, unnecessary right The circularly polarized wave is absorbed by the magnetic resonance phenomenon, and only the left-handed circularly polarized wave desired to be received passes through the ferrite rod 5 and is output. Therefore, it is possible to combine only one of the orthogonal linearly polarized components of the left-handed circularly polarized wave with the probe 7, extract the signal as a signal, and input it to the converter.

Therefore, one primary radiator located at the focal point of the reflector is used to direct the reflector towards each satellite and to obtain the desired polarization from the vertically polarized and horizontally polarized waves introduced in the same primary radiator. Whichever is desired to output as a signal and input to the converter, or the desired one from right-handed and left-handed circularly polarized waves introduced in the same primary radiator, and output as a signal and input to the converter. By selecting the local oscillation frequency with the same converter to select a desired polarization from horizontal polarization, vertical polarization, left-hand circular polarization, and right-hand circular polarization, and receiving. Is possible. Therefore, since only one primary radiator needs to be attached to the reflector, the mounting structure is simple, and since the driving unit is not used as the primary radiator, the structure is simple and the price can be reduced.

FIG. 4 is an explanatory view showing a second embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view. The same parts as those shown in FIGS. 1A and 1B are designated by the same reference numerals and the description thereof will be omitted. The difference from the embodiment of FIGS. 1A and 1B is that a substantially rectangular resistance plate 10 is provided in a direction perpendicular to the end surface 4 of the circular waveguide 3. The resistance plate 10 has a length substantially equal to the diameter of the circular waveguide 3 so as to pass through the tube axis of the circular waveguide 3, and both ends are clamped and fixed by the inner wall of the circular waveguide 3, for example. (B) When viewed from the front as shown in the figure, the probe 7 is arranged so as to be orthogonal to the probe 7. With this arrangement, the resistance plate 10 becomes parallel to the direction of the electric field of the cross polarization with respect to the polarization of the reception desired, so that the cross polarization can be attenuated by the resistance plate 10 and the reception desired. The polarized wave can be coupled to the probe 7 and output.

FIG. 5 is an explanatory view showing a third embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view. The same parts as those shown in FIGS. 4A and 4B are designated by the same reference numerals and the description thereof will be omitted. 4A and 4B is different from the embodiment shown in FIGS. 4A and 4B in that a substantially rectangular metal plate is used instead of the resistance plate 10 used for attenuating an unwanted mode with respect to a desired signal. 11 is used and is arranged between the ferrite rod 5 and the probe 7. The metal plate 11 has a length substantially equal to the diameter of the circular waveguide 3 so as to pass through the tube axis of the circular waveguide 3, and both ends are clamped and fixed by the inner wall of the circular waveguide 3, for example. (B) When viewed from the front as shown in the figure, the probe 7 is arranged so as to be orthogonal to it. With such an arrangement, the metal plate 11 becomes parallel to the electric field direction of the cross polarization with respect to the polarization desired to be received, so that the cross polarization can be reflected by the metal plate 11 and the desired reception can be obtained. The polarized wave can be coupled to the probe 7 and output.

FIG. 6 is an explanatory view showing a fourth embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view. The same parts as those shown in FIGS. 1A and 1B are designated by the same reference numerals and the description thereof will be omitted. The difference from the embodiment of FIGS. 1A and 1B is that instead of using the probe 7 as the output means from the circular waveguide 3, a rectangular waveguide 13 is provided on the side surface of the circular waveguide 3. It is the point of joining. A rectangular waveguide 13 is joined to the side surface of the circular waveguide 3 on the side of the termination surface 4 as an output means of the radio wave introduced into the circular waveguide 3, and the tube axis of the rectangular waveguide 13 is extended. The line and the tube axis of the circular waveguide 3 are orthogonal to each other, the circular waveguide 3 and the rectangular waveguide 13 are connected via the opening 12, and the opening 12 is a substantially rectangular slit. Arranged so that the direction is parallel to the tube axis of the circular waveguide 3, the length is set to about half the wavelength of the radio wave to be output, and the radio wave can be output from the rectangular waveguide 13.

[0019]

[Effect of device]

 As described above, according to the present invention, by controlling the DC magnetic field applied to the ferrite rod, the direction of the electric field of horizontal polarization or vertical polarization is relatively adjusted by the ferrite rod with respect to linear polarization. Since it can be rotated, it becomes possible to select the desired linearly polarized wave and output it from the output means. For circularly polarized wave, one is absorbed by the magnetic resonance phenomenon and only the other is passed and output. Since it is possible to select a desired circularly polarized wave and output it from the output means, therefore, among the horizontally polarized wave, the vertically polarized wave, the left-handed circular polarization, and the right-handed circular polarization, It is possible to provide a primary radiator that can select and receive a desired polarized wave and that has a simple structure and is inexpensive.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a first embodiment of a primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view.

FIG. 2 is an explanatory diagram of microwave magnetic permeability characteristics of a ferrite rod.

FIG. 3 is an explanatory diagram of Faraday rotation of a circular waveguide loaded with a ferrite rod.

FIG. 4 is an explanatory view showing a second embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view.

FIG. 5 is an explanatory view showing a third embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view.

FIG. 6 is an explanatory view showing a fourth embodiment of the primary radiator of the present invention, (A) is a partially cutaway perspective view, and (B) is a front view.

FIG. 7 is an explanatory view showing a conventional example, (A) is a partially cutaway perspective view of a primary radiator for receiving circularly polarized waves, and (B) is a primary radiator for receiving linearly polarized waves. It is a partially notched perspective view.

[Explanation of symbols]

 1 Aperture 2 Circular Waveguide 3 Circular Waveguide 4 End Surface 5 Ferrite Rod 6 Excitation Coil 7 Probe 8 Through Hole 9 Leader Line 10 Resistor Plate 11 Metal Plate 12 Slit 13 Square Waveguide 20 Circular Waveguide 21 Dielectric Body plate 22 Probe 23 Drive part 24 Probe 25 End surface 26 Rectangular waveguide

Claims (5)

[Scope of utility model registration request] 1. A first circular waveguide whose one end is provided with an opening for introducing a radio wave and whose other end is a connection end, and a second circular waveguide whose one end is provided with a termination surface and whose other end is a connection end. A tube; a ferrite rod concentrically connected to each of the connecting ends of the first and second circular waveguides; an exciting coil wound around the ferrite rod to apply a DC magnetic field; And a rectangular waveguide provided as a means for outputting a radio wave introduced into the circular waveguide, and the first circular conductor is set by setting the DC magnetic field of the ferrite rod to a predetermined value within the Faraday rotation region. A primary radiator characterized by selecting a polarized wave signal desired to be received from the horizontally polarized wave or the vertically polarized wave introduced into the wave tube and outputting it from the output means. 2. A first circular waveguide having an opening for introducing a radio wave at one end and having the other end as a connection end, and a second circular waveguide having an end surface at one end and the other end as a connection end. A tube; a ferrite rod concentrically connected to each of the connecting ends of the first and second circular waveguides; an exciting coil wound around the ferrite rod to apply a DC magnetic field; And a probe provided as a means for outputting a radio wave introduced into the circular waveguide, and by setting the DC magnetic field of the ferrite rod to a predetermined value within the Faraday rotation region, A primary radiator characterized in that a polarized signal desired to be received is selected from the introduced horizontally polarized waves or vertically polarized waves and is outputted from said output means. 3. One of the right-handed or left-handed circularly polarized waves introduced into the first circular waveguide is magnetized by setting the DC magnetic field of the ferrite rod to a predetermined value within the magnetic resonance region. 3. The primary radiator according to claim 1, wherein a circular polarized wave desired to be received is selected by the resonance phenomenon and passed through the other, and is output from the output means. 4. A substantially rectangular resistance plate is provided between the output means and the terminal surface so as to pass through the tube axis of the second circular waveguide and to be perpendicular to the terminal surface. 4. The resistance plate is arranged so as to be parallel to the direction of the electric field of the cross polarization with respect to the desired polarization, and the cross polarization is attenuated by the resistance plate. Primary radiator. 5. A substantially rectangular shape that passes through the tube axis of the second circular waveguide between the ferrite rod and the output means, and is oriented parallel to the tube axis of the second circular waveguide. A metal plate is provided, the metal plate is arranged so as to be parallel to the direction of the electric field of the cross polarization with respect to the desired polarization, and the cross polarization is attenuated by the metal plate. The primary radiator according to 2 or 3.