JPH03243002A - Circular polarization/linear polarization converter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a circular polarization/linear polarization converter, and in particular to a circular polarization converter for electromagnetic waves used to reduce interference between two satellite broadcasting systems. This invention relates to a circular polarization/linear polarization converter used on the reception side and the transmission side for polarization. Here, the circularly polarized wave/linearly polarized wave converter includes a linearly polarized wave to circularly polarized wave converter and a circularly polarized wave to linearly polarized wave converter.

Broadcasting satellites in Japan emit right-handed circularly polarized electromagnetic waves as broadcast signals, and in order to create right-handed circularly polarized waves, a circular polarization converter is used to convert the linearly polarized waves into circularly polarized waves at the power feeding section of the antenna of the equipment onboard the satellite. In addition, right-handed circularly polarized electromagnetic waves from a broadcasting satellite are received by a reflector of a receiving BS antenna on the ground as shown in Figure 5, and the electromagnetic waves reflected by the reflector are reflected by the reflector. The electromagnetic waves are incident on the aperture of the primary radiator installed at the focal point of the wave, and then the electromagnetic waves are incident on the structural part that converts the circularly polarized waves into linearly polarized waves. It is converted into a linearly polarized wave and inputted to the low noise amplifier LNB of the BS converter, where it is converted into an electrical signal and signal processing is performed.

In principle, the linear polarization/circular polarization converter used in satellite equipment and the circular polarization/linear polarization converter used in ground receiving equipment are based on the same principle. can.

[Prior Art] FIG. 6 shows a conceptual diagram of a circularly polarized wave/linearly polarized wave converter used in conventional terrestrial receiving equipment, viewed from the side. The primary radiator has a horn-shaped shape to efficiently collect the electromagnetic waves reflected by the reflector of the BS antenna and guide them to the waveguide. Part A of the waveguide receives the broadcast waves generated in part B. It is a circular waveguide section provided to attenuate higher-order modes other than the fundamental mode of electromagnetic waves necessary for The input circularly polarized electromagnetic wave is converted into a linearly polarized wave in the phase circuit structure that converts the circularly polarized wave/linearly polarized wave. guided by the parts. Section C is a circular waveguide section, which is provided to attenuate higher-order modes generated at the junction between the phase circuit structure section and the circular waveguide section. Part D is for coupling the linearly polarized NWa wave using an excitation probe made of metal poles to match the impedance of the waveguide and excitation probe in order to efficiently extract the signal to the outside of the waveguide. The signal extracted by the excitation probe was input to a low-noise amplifier LNB attached to the side of the waveguide, where signal processing was performed.

Circularly polarized waves are two orthogonal linearly polarized waves whose amplitude and frequency are equal and whose phases are shifted by 90 degrees.If a phase circuit is installed to bring the phases of both linearly polarized waves into the same phase, it can be converted into a linearly polarized signal. However, examples of phase circuit structures conventionally used for converting circularly polarized waves/linearly polarized waves are shown in FIG. 7(a), [present]) and FIG. 8(a), et al.). In the figure, (a) is a front view seen from the opening of the waveguide, and (b) is a side view of the phase circuit section of the waveguide.

FIG. 7 shows a dielectric plate 22 that is tilted at 45 degrees to the direction of the linearly polarized wave extracted as a signal by the coupling means and parallel to the vertical electric field component Y of one of the two linearly polarized waves orthogonal to each other. is attached inside the waveguide 21. By attaching the dielectric plate 22 inside the waveguide 21 in this way, the phase of the linearly polarized wave of the electric field component parallel to the dielectric plate 22 can be delayed, and therefore the phase of the linearly polarized wave of the other horizontal direction of the linearly polarized wave can be delayed. If the longitudinal dimensions of the dielectric plate 22 are selected to such a length that the component Y lags the electric field component Become. In addition to this, the following are used as examples of phase circuit structures with such an effect. 8th
Figures (a) and (b) show a phase circuit structure in which two metal plates 23 are installed at the centers of opposing circular arcs on the inner surface of the waveguide 21, so that the short side direction of each metal plate 23 is the waveguide. A metal plate 23 is attached so as to be directed toward the center of the pipe 21 and further extended in the longitudinal direction of the waveguide 21.

[Problem to be solved by the invention]

Therefore, it is necessary to secure a predetermined distance between the phase circuit shown in FIG. 7 or FIG. In the LNB type with an integrated feedphone, in which the LNB is attached to the side of the LNB, when checking the electrical performance of the LNB section, it is necessary to input a circularly polarized wave signal from the primary radiator section, making the measurement difficult. There were problems in that it was difficult to remove and accurate measurements could not be made.

An object of the present invention is to provide an opening for positioning on the side surface of a waveguide to facilitate the assembly work and measurement work described above.

[Means to solve the problem]

As shown in Fig. 1 (a), (b) and Fig. 2 (a), (b), the primary radiator 1 has a horn-shaped shape, and the smaller opening surface of the primary radiator l. A phase circuit B part for converting between circularly polarized waves and linearly polarized waves is provided inside the waveguide 5 by joining the opening surface of one end of the waveguide 5, and a predetermined distance C is provided from the phase circuit. A coupling means 2 for transmitting signals between an electromagnetic wave in a pipe and an external circuit of a waveguide, and a circularly polarized/linearly polarized wave having a termination surface 6 at a predetermined distance @D from the coupling means. In the converter, when assembling the circularly polarized wave/linearly polarized wave converter, an opening 9 for inserting the guide is provided on the side surface of the waveguide 5, the guide is inserted into the waveguide, and the phase circuit structure 3 and 11
is inserted into the waveguide 5 so as to butt against the guide, and a predetermined distance C is secured between the coupling means 2 and the structures 3 and 11 so that the circularly polarized wave/linearly polarized wave When confirming the characteristics of the circularly polarized wave/linearly polarized wave converter during assembly of the wave converter, the structures 3 and 11 of the phase circuit are installed on the side surface of the waveguide 5 before facing the waveguide. The guide 10 is inserted into the waveguide 5 through the guide insertion opening 8, and the shorting plate 21 is inserted into the waveguide 5 from the primary radiator 1 side so as to abut against the guide 10. A performance evaluation test can be performed by removing the termination surface 6 and inputting a test signal into the waveguide 5 from the side from which the termination surface 6 has been removed.

[Effect]

In the present invention, as described above, the side wall of the waveguide is provided with an opening for assembly work, an opening for measurement work, or both of the openings, and the opening is used to attach the structure of the phase circuit. By locating the short-circuit plate for measurement, or by locating the short-circuit plate for measurement, assembly work and characteristic confirmation work can be easily performed.

〔Example〕

FIGS. 1(a), 2) to 2(a), (b) show a circularly polarized wave/linearly polarized wave converter showing an embodiment of the present invention,
In the figure, (a) is a front view of the circularly polarized wave/linear polarized wave converter seen from the aperture surface of the primary radiator, and (b) is the same as the above figure (a) at 42-f.
Figure 1 is an example in which a dielectric plate is used as a phase circuit, and Figure 2 is an example in which a metal plate is used as a phase circuit. This is an example.

As shown in Fig. 1 (a), (b) and Fig. 2 (a), (b), the primary radiator 1 has a horn-shaped shape, and the smaller aperture of the primary radiator 1 One end of the opening surface of the waveguide 5 is joined, a phase circuit B section for converting between circularly polarized waves and linearly polarized waves is provided inside the waveguide 5, and a predetermined distance C is established from the same phase circuit B section. A coupling means for transmitting a signal between the electromagnetic waves in the pipe and the LNBd is provided, and an excitation probe 2 shown in the figure is provided, and a termination surface 6 is provided with a predetermined distance 1i11D from the excitation probe 2.
is fixed to the other end of the opening surface of the waveguide 5 by a screw 7 or the like.

In FIGS. 1 and 2 (a), if the vertical center line of the circular waveguide 5 is the Y axis, the excitation probe 2
The excitation probe 2 is attached so that an extension of the center of the waveguide and the Y-axis form an angle of 45 degrees, and an opening 9 is provided on the side surface of the waveguide 5 so that the center of the opening coincides with the Y-axis. A guide pin is inserted into the waveguide 5 through the opening 9, and the short side of the dielectric plate 3 or metal plate 10 used as a structure of the phase circuit is parallel to the Y axis. The excitation probe 2 is inserted into the tube 5 and butts against the guide pin, thereby securing a predetermined distance C from the excitation probe 2 and facing the dielectric plate 3 or the metal plate 10.

When the dielectric plate 3 is to be surfaced, the opening 9 is provided on at least one of the upper and lower sides of the side wall of the waveguide, and when the metal plate 10 is to be surfaced, the opening 9 is provided on the upper and lower sides of the side wall of the waveguide. The two metal plates 10 are surfaced using guide pins provided on both sides and passed through the respective openings.

In Figure 3, a guide pin 11 is passed through an opening 9 provided at both the upper and lower sides of the side wall of the waveguide, and two metal plates 10 are attached. The guide pin 11 may be left attached using a material. It is desirable to seal the opening 9 or to use a waterproof cover over the entire circularly polarized/linearly polarized wave converter to prevent rainwater etc. from entering the inside of the waveguide.

Further, when implementing the present invention by providing only an opening for surface determination of a phase circuit in the side wall of the waveguide, the termination surface 6 does not necessarily have to be structured to be removable.

When checking the characteristics of a circularly polarized wave/linearly polarized wave converter of a manufactured product for quality control reasons, the terminal surface 6 of the waveguide 5 is used.
The excitation probe 2 is attached to the waveguide 5 using a mounting bracket, and the excitation probe 2 is attached to the side surface of the waveguide 5 so that the center of the opening 8 and the Y axis coincide with the opening 9. A guide insertion opening 8 for measurement is provided at a distance horizontally from the waveguide, and a guide pin 12 is inserted into the waveguide 5 as shown in FIG. Insert the shorting plate 13 into the tube 5 so that it abuts against the guide pin 12, remove the terminal surface 6, and attach the waveguide adapter 14 to the terminal surface 6. Regarding the LNB type integrated feed phone in which the test signal is input into the waveguide 5 through the opening of the side waveguide adapter 14 and the LNB is attached to the side of the waveguide, the waveguide section This allows testing to confirm the electrical performance of the LNB including its gain, NF, input VSWR, etc.

〔Effect of the invention〕

As explained above, according to the present invention, an opening for positioning is provided in the wall surface of the waveguide, and the position of the short circuit plate for measuring the characteristics of the structure of the phase circuit or the circularly polarized wave/linearly polarized wave converter is installed. By using it for loading, assembly and measurement work can be easily done.

[Brief explanation of drawings]

Figures 1 (a) and (b) show a circularly polarized wave/linearly polarized wave converter using a dielectric plate as a phase circuit according to an embodiment of the present invention, in which (a) shows the primary radiation A front view of the circularly polarized wave/linearly polarized wave converter as seen from the aperture of the device, (b) is a cross-sectional view of the side of the circularly polarized wave/linearly polarized wave converter, and Figure 2 (a), This figure shows a circularly polarized wave/linearly polarized wave converter using a metal plate as a phase circuit showing an embodiment of the invention, and (a) in the figure shows the circularly polarized wave/linearly polarized wave as seen from the aperture surface of the primary radiator. FIG. 3 is a front view of the polarization converter, (b) is a side sectional view of the circularly polarized/linearly polarized converter, and FIG. FIG. 4 is a cross-sectional view of the side surface of the circularly polarized wave/linearly polarized wave converter, showing a state in which a guide pin is inserted into the measurement opening according to one embodiment of the present invention. 5 is a schematic side view of a receiving BS antenna, FIG. 6 is a conceptual diagram of a circularly polarized wave/linear polarized wave converter showing a conventional example, and FIGS. 7 (a), (b) to 8 Figures (a), (b)
1 is a diagram showing a phase circuit structure of a conventional example. 1-Primary radiator, 2-・-excitation probe, 3゜22-
Dielectric plate, 4- LNB, 5, 21 waveguide, 6- termination surface, 7---- screw, 8, 9---- opening, 1
0.23- Metal plate, 11.12-・Guide pin, l
3- shorting plate, 14- waveguide adapter. Figure 1 (al ρ4 et al.) Figure 2 (a) (I)) Figure 3

Claims (2)

[Claims] (1) A horn-shaped primary radiator and circularly polarized and linearly polarized waves provided inside the waveguide by joining the opening at one end of the waveguide to the smaller opening of the primary radiator. A circularly polarized wave/linearly polarized wave converter comprising: a phase circuit that performs conversion between waves; a coupling means provided at a predetermined distance from the phase circuit; and a termination surface provided at a predetermined distance from the coupling means. A structure in which a first opening for inserting a guide is provided on a side surface of the waveguide, the first guide is inserted into the waveguide through the opening, and the phase circuit converts between circularly polarized wave and linearly polarized wave. A circularly polarized wave/linearly polarized wave converter, characterized in that an object is inserted into the waveguide from the primary radiator side so as to abut against the first guide, and surface measurement is performed. (2) A horn-shaped primary radiator and circularly polarized and linearly polarized waves created inside the waveguide by joining the opening at one end of the waveguide to the smaller opening of the primary radiator. A circularly polarized wave/linearly polarized wave converter comprising: a phase circuit that performs conversion between waves; a coupling means provided at a predetermined distance from the phase circuit; and a termination surface provided at a predetermined distance from the coupling means. A second opening for inserting a guide is provided in the side surface of the waveguide, the second guide is inserted into the waveguide through the opening, and the guide is brought into contact with the guide from the primary radiator side. A circularly polarized wave/linearly polarized wave conversion characterized in that it is possible to perform a performance evaluation test by inserting a shorting plate in this way and inputting a test signal into the waveguide from the side with the terminal surface open. vessel.