JPH08195601A - Polarization demultiplexer - Google Patents

Abstract

PURPOSE: To demultiplex two parallel polarized waves, not to mention vertical polarized waves, and to reduce the size of the polarization demultiplexer. CONSTITUTION: This polarization demultiplexer is equipped with a circular waveguide 11, a 1st rectangular waveguide 12 which is connected through a 1st coupling hole 15 provided at one end part of the circular waveguide 11, and a 2nd rectangular waveguide 13 which is connected through a 2nd coupling hole 16 provided at part of the tube wall of the circular waveguide 11. The 1st rectangular waveguide 12 has its tube axis directed at right angles to the tube axis of the circular waveguide 11 and the 2nd rectangular waveguide 13 has its tube axis directed at right angles to the tube axis of the circular waveguide 11 and the tube axis of the 1st rectangular waveguide 12. The tube axis of the 1st rectangular waveguide 12 is directed at right angles to the tube axis of the circular waveguide 11, so the length of the circular waveguide 11 in the tube axis direction be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveguide-type demultiplexer suitable for use as a transmission / reception antenna for satellite communication, and more particularly to a demultiplexer having a reduced length in the axial direction of the waveguide. Regarding vessels.

[0002]

2. Description of the Related Art In an antenna for both transmission and reception of satellite communication, a demultiplexer is used because it is required to separate a transmission wave and a reception wave. In this case, when the two signal waves to be demultiplexed are orthogonally polarized waves, as shown in FIG.
The technique described in Japanese Patent Laid-Open No. 218702 is adopted.
In this technique, a transmission-side rectangular waveguide 42 that transmits a transmission signal is connected to one end of a circular waveguide 41 in a communication state in parallel with the tube axis direction of the circular waveguide 41. In addition, a coupling hole 46 is formed in a part of the wall of the circular waveguide 41, and a receiving side rectangular waveguide 43 for introducing a reception signal is connected to the coupling hole 46 in a direction perpendicular to the tube axis direction.

Therefore, the transmission signal transmitted from the transmission-side rectangular waveguide 42 is propagated in the circular waveguide 41 with the electric field directed vertically, so that the reception-side rectangular waveguide 4 is transmitted.
It is not leaked to 3. On the other hand, since the electric field of the received signal propagating in the circular waveguide 41 is directed horizontally, the signal is propagated to the receiving rectangular waveguide 43, but leaks to the transmitting rectangular waveguide 42. There is no.

However, although such a demultiplexer is effective for orthogonal polarized waves, it can be used for parallel polarized waves whose electric field directions are the same.
It is difficult to split two signal waves. Therefore, as a configuration for demultiplexing two signal waves composed of parallel polarized waves of different frequencies, a demultiplexer as shown in FIG. 5 has been proposed. In this demultiplexer, a transmission side rectangular waveguide 52 is connected to a circular waveguide 51, and a reception side rectangular waveguide 53 is connected via a coupling hole 56. Then, the second circular waveguide 57 and the round-angle conversion waveguide 58 are interposed between the circular waveguide 51 and the transmission-side rectangular waveguide 52.

The diameter of the second circular waveguide 57 is such that the received signal does not propagate and only the transmitted signal can propagate. The round-angle conversion waveguide 58 includes the second circular waveguide 57 and the transmission side rectangle. This is for impedance matching with the waveguide 52. In this case, the transmission signal frequency fH is higher than the reception signal frequency fL, and the tube diameter of the second circular waveguide is made smaller than that of the circular waveguide.

In the demultiplexer of FIG. 5, the received signal is the second signal.
Since it does not propagate through the circular waveguide 57, it does not propagate through the transmission-side rectangular waveguide 52. Further, by designing the coupling hole 56 of the reception side rectangular waveguide 53 in the frequency band of the reception signal, the coupling hole becomes a short surface for the transmission signal, and the transmission signal is transmitted to the reception side rectangular waveguide 53. It will not be propagated.

[0007]

However, in such a demultiplexer shown in FIG. 5, the second circular waveguide 57 and the round-angle conversion waveguide 58 are arranged in the tube axis direction of the circular waveguide 51. connection,
Furthermore, since the transmission side rectangular waveguide 52 is connected, the dimension in the tube axis direction becomes extremely long, and there is a problem that it is difficult to apply it to a satellite communication antenna or the like.

Regarding the point of reducing the length in the tube axis direction, one technique is proposed in Japanese Patent Application Laid-Open No. 5-206702, but this technique is for demultiplexing orthogonal polarized waves. When demultiplexing such parallel polarized waves, it cannot be applied as it is. Further, even in the case of demultiplexing the orthogonal polarized waves, the structure becomes complicated because components such as a dual coaxial line and a probe are required.

[0009]

It is an object of the present invention to provide a demultiplexer capable of demultiplexing two signal waves of parallel polarization while reducing the length in the tube axis direction. is there. Also,
Another object of the present invention is to provide a demultiplexer that demultiplexes a signal wave of orthogonal polarization while reducing the length in the tube axis direction and simplifying the configuration. .

[0010]

A polarization splitter of the present invention comprises a circular waveguide and a first waveguide provided at one end of the circular waveguide.
A first rectangular waveguide connected through a coupling hole, and a second rectangular waveguide connected through a second coupling hole provided in a part of the wall of the circular waveguide The first rectangular waveguide has its tube axis oriented perpendicular to the tube axis of the circular waveguide, and
Of the rectangular waveguide is oriented such that its tube axis is perpendicular to the tube axis of the circular waveguide and the tube axis of the first rectangular waveguide.

In another polarization splitter of the present invention, the tube axis of the first rectangular waveguide is oriented perpendicular to the tube axis of the circular waveguide, and the second rectangular waveguide thereof is The tube axis is oriented parallel to the tube axis of the first rectangular waveguide.

Further, in another polarization splitter of the present invention, the first rectangular waveguide has its tube axis oriented perpendicular to the tube axis of the circular waveguide, and the second rectangular waveguide has The first coupling hole and the second coupling hole, each having a tube axis oriented parallel to the tube axis of the first rectangular waveguide and connecting each rectangular waveguide and the circular waveguide, are formed in the circular waveguide. Opened on a vertical surface.

[0013]

Since the tube axis of the first rectangular waveguide is oriented in the direction perpendicular to the tube axis of the circular waveguide, it is possible to reduce the length of the circular waveguide in the tube axis direction. Moreover, since the tube axis of the second rectangular waveguide is oriented in the direction parallel to the tube axis of the first rectangular waveguide, the rectangular waveguide is guided only in one direction perpendicular to the tube axis of the circular waveguide. The tube is present and the length in the other direction is reduced. Further, by providing the first and second coupling holes on the vertical surface of the circular waveguide, it is possible to split vertically polarized waves without using other components.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of the present invention,
(A) is a perspective view, (b) is a side view seen from the right side. In this embodiment, the transmission signal of high frequency fH and the reception signal of low frequency fL are parallel polarized waves, and an example of a demultiplexer that demultiplexes these signals is shown. A horizontally long first coupling hole 15 is opened at one end of the circular waveguide 11, and the transmission side rectangular waveguide 12 is connected through the first coupling hole 15. The transmission side rectangular waveguide 12 is connected so that its tube axis is perpendicular to the tube axis of the circular waveguide 11, and the electric field direction of the transmission signal fH in the transmission side rectangular waveguide 12 is circular waveguide. It is set so as to be oriented in the tube axis direction of the tube 11. Further, the first coupling hole 15 is opened in the horizontal direction.

Further, a part of the tube wall of the circular waveguide 11,
Here, a horizontally-long second coupling hole 16 is opened at the side position,
The receiving side waveguide 13 is connected through the second coupling hole 16. The receiving side waveguide 13 has its tube axis oriented in the horizontal direction, and is set so that the electric field direction of the received signal fL is oriented in the vertical direction. Further, the second coupling hole 16 is opened in the horizontal direction. Further, a receiving filter 14 capable of passing the received signal fL band is connected to the receiving side waveguide 13.

In this embodiment, the lower end 12a of the transmission side rectangular waveguide 12 is connected to a transmitter (not shown),
The tip portion 13a of the receiving side rectangular waveguide 13 including the receiving filter 14 is connected to a receiver (not shown), and the circular waveguide 11
It is assumed that the other end 11a of is connected to the antenna for both transmission and reception. Further, it is assumed that the transmission signal and the reception signal are propagated in the circular waveguide 11 with the electric field direction thereof being oriented in the vertical direction.

According to the demultiplexer having this structure, the transmission signal from the transmitter (not shown) is propagated in the transmission side rectangular waveguide 12 and then is transmitted from the first coupling hole 15 into the circular waveguide 11. Propagated to. At this time, by appropriately setting the distance between the first coupling hole 15 and the short-circuited side of the upper end of the transmission-side rectangular waveguide 12 based on the frequency of the transmission signal fH, a characteristic with less standing waves is obtained, and the transmission signal is reduced. Is the circular waveguide 11 through the first coupling hole 15.
Will be excited by. Then, the transmission signal fH propagates through the circular waveguide 11 and is fed to the transmission / reception shared antenna.

On the other hand, for the received signal fL propagated from the transmitting / receiving antenna, the dimensions of the second coupling hole 16 are designed in the frequency band of the received signal, and the second coupling hole 16 and the circular waveguide 11 are arranged.
By properly setting the distance from one end of the circular waveguide 11 based on the frequency of the received signal, the characteristic that the standing wave of the received signal in the circular waveguide 11 is small is obtained, and the received signal is the second coupling hole. It is excited by the receiving side rectangular waveguide 13 via 16, propagates in the receiving side rectangular waveguide 13 and is input to the receiver.

Here, since the second coupling hole 16 is designed in the frequency band of the received signal, theoretically the circular waveguide 1
Although the transmission signal propagated through 1 does not leak to the receiving side rectangular waveguide, in reality, a part thereof may leak. However, since the reception filter 14 is connected to the reception side rectangular waveguide 13, the transmission signal is blocked by the reception filter 14 and does not reach the receiver.

Since the first coupling hole 15 is designed based on the frequency of the transmission signal, the reception signal does not leak to the transmission side rectangular waveguide 12. Further, even if a part is leaked, it is attenuated at the time of leaking into the transmission side rectangular waveguide 12 and is hardly propagated to the transmitter.

Therefore, in the demultiplexer of the first embodiment, the second circular waveguide, the round-angle conversion waveguide, etc. are not connected to the end of the circular waveguide 11, and Since the transmitting rectangular waveguide 12 has a tube axis perpendicular to the circular waveguide 11, the length of the circular waveguide 11 in the tube axis direction can be extremely short. As a result, the demultiplexer of this embodiment can be applied to a small transmitting / receiving antenna.

2A and 2B are views showing a second embodiment of the present invention, in which FIG. 2A is a perspective view and FIG. 2B is a side view from the right direction. Also in this embodiment, the high frequency transmission signal fH
2 shows an example of a demultiplexer when both the low frequency reception signal fL and the low frequency reception signal are parallel polarized waves. In this embodiment, the circular waveguide 21
To the transmission side rectangular waveguide 2 connected to the first coupling hole 15 through
The structure of 2 is the same as that of the first embodiment, but the receiving side rectangular waveguide 23 has its tube axis perpendicular to the tube axis of the circular waveguide 21 and parallel to the tube axis of the transmitting side rectangular waveguide 22. Is configured to be. The structure of the second coupling hole 26 is the same as that of the first embodiment. However, the distance between the short-circuit side of the reception-side rectangular waveguide 23 and the second coupling hole 26 is appropriately designed based on the frequency of the reception signal fL. A reception filter 24 is connected to the reception-side rectangular waveguide 23.

In this configuration, the propagation of the transmission signal from the transmission side rectangular waveguide 22 to the circular waveguide 21 is the same as that of the first embodiment. The same applies when the reception signal is leaked to the transmission-side rectangular waveguide 22. On the other hand, the received signal is substantially the same as that of the first embodiment, but here, by appropriately setting the distance between the short-circuit side of the receiving-side rectangular waveguide 23 and the second coupling hole 26, the transmitted signal is Even if part of fH leaks to the receiving side rectangular waveguide 23, the transmission signal is attenuated at the time of leaking. Further, even when the attenuation is not sufficient, it is blocked by the reception filter 24 connected to the reception side rectangular waveguide 23 and is prevented from being input to the receiver.

In the second embodiment, the transmission side rectangular waveguide 2 is used.
2 is parallel to the receiving side rectangular waveguide 23, the length of the circular waveguide 21 in the tube axis direction can be reduced.
The same as the embodiment, but in addition to this, the length of the circular waveguide 21 in the direction perpendicular to the tube axis can be limited to one direction. As compared with the configuration in which the rectangular waveguide is extended in two directions with respect to the tube axis, it is possible to further reduce the external dimensions of the demultiplexer.

3A and 3B are views showing a third embodiment of the present invention. FIG. 3A is a perspective view and FIG. 3B is a right side view.
In this embodiment, the transmission signal fH and the reception signal fL show an example of orthogonal polarization, and the electric field direction of the transmission signal fH is the vertical direction in the circular waveguide 31, and the reception signal fL.
Shows an example in which the electric field direction is horizontal. In FIG. 3, the configuration of the transmission side rectangular waveguide 32 connected to the circular waveguide 31 through the first coupling hole 35 is the same as in the first and second embodiments, but the second coupling hole 36 is circular. It is provided on the lower tube wall of the waveguide 31, and is provided on a surface different from the first coupling hole 35 in the vertical direction. In addition, the receiving side rectangular waveguide 33 connected through the second coupling hole 36 has a tube axis direction perpendicular to the tube axis of the circular waveguide 31 as in the second embodiment and a transmitting side rectangular waveguide. It is configured to be parallel to the tube axis of the wave tube 32.

In this structure, the propagation of the transmission signal from the transmission side rectangular waveguide 32 to the circular waveguide 31 is the same as that of the first embodiment. Further, the received signal in the circular waveguide 31 has the second coupling hole 36 formed in the lower tube wall of the circular waveguide 31, so that the received signal is the received rectangular waveguide 3.
3 is propagated. At this time, the first and second coupling holes 3
Since 5 and 36 are oriented in the vertical direction, the transmission signal and the reception signal are prevented from leaking to the reception side rectangular waveguide 33 and the transmission side rectangular waveguide 32, respectively.

Also in the third embodiment, as in the second embodiment, since the tube axes of the transmitting side rectangular waveguide 32 and the receiving side rectangular waveguide 33 are parallel, the tube axis of the circular waveguide 31 is the same. The length in the direction can be reduced, and the length of the circular waveguide 31 in the direction perpendicular to the tube axis can be limited to one direction, and the outer size of the demultiplexer can be further reduced. . Further, unlike the prior art, it is not necessary to dispose a double coaxial line, a probe, or the like on the circular waveguide, so that the configuration can be simplified.

Here, in the above embodiment, the case where the transmission signal has a higher frequency than the reception signal has been described as an example, but conversely, the present invention can be similarly applied even when the reception signal has a higher frequency than the transmission signal. it can. Further, in the above embodiment, an example of demultiplexing the transmission signal and the reception signal is shown, but if the purpose is to demultiplex two signal waves having different frequencies or two orthogonally polarized signal waves, Needless to say, the use of the signal wave is not limited.

Further, the directions of the rectangular waveguides in each of the above embodiments are merely examples, and the rectangular waveguide is integrated with the circular waveguide or the rectangular waveguide is circular waveguide. However, it goes without saying that the configuration may be such that the circular waveguide is rotated around the tube axis.

[0030]

As described above, according to the present invention, the first rectangular waveguide connected through the first coupling hole provided at one end of the circular waveguide has a circular tube axis. A second rectangular waveguide, which is oriented perpendicular to the waveguide axis and is connected through a second coupling hole provided in a part of the circular waveguide wall, has a circular guide axis. Since it is oriented perpendicular to the tube axis of the wave guide and the tube axis of the first rectangular wave guide, respectively, parallel polarization can be demultiplexed, and in particular, the circular guide of the first rectangular wave guide is provided. The length of the wave tube in the tube axis direction can be reduced, and the demultiplexer can be downsized.

In the other demultiplexer of the present invention, the first rectangular waveguide has its tube axis oriented perpendicularly to the tube axis of the circular waveguide, and the second rectangular waveguide has the same tube axis. Since the tube axis is oriented parallel to the tube axis of the first rectangular waveguide, the first and second rectangular waveguides are present only in one direction perpendicular to the tube axis of the circular waveguide. Therefore, the length of the circular waveguide in the other direction perpendicular to the tube axis can be reduced, and the size of the demultiplexer can be reduced.

Furthermore, in another polarization splitter of the present invention, the first rectangular waveguide has its tube axis oriented perpendicularly to the tube axis of the circular waveguide, and the second rectangular waveguide has The first coupling hole and the second coupling hole, each having a tube axis oriented parallel to the tube axis of the first rectangular waveguide and connecting each rectangular waveguide and the circular waveguide, are formed in the circular waveguide. By opening on a vertical surface, demultiplexing of vertically polarized waves becomes possible without using other components, and simplification of the configuration of the polarization demultiplexer can be realized.

[Brief description of drawings]

FIG. 1 is a perspective view and a right side view of a first embodiment of a demultiplexer of the present invention.

FIG. 2 is a perspective view and a right side view of a second embodiment of the demultiplexer of the present invention.

FIG. 3 is a perspective view and a right side view of a third embodiment of the demultiplexer of the present invention.

FIG. 4 is a perspective view of an example of a conventional polarization demultiplexer and a right side view thereof.

FIG. 5 is a perspective view and another right side view of another example of the conventional polarization demultiplexer.

[Explanation of symbols]

 11, 21, 31 circular waveguide 12, 22, 32 transmitting side rectangular waveguide 13, 23, 33 receiving side rectangular waveguide 14, 24 receiving filter 15, 25, 35 first coupling hole 16, 26, 36 Second coupling hole

Claims (5)

[Claims] 1. A circular waveguide, a first rectangular waveguide connected through a first coupling hole provided at one end of the circular waveguide, and a tube of the circular waveguide. A second rectangular waveguide connected through a second coupling hole provided in a part of the wall, and the tube axis of the first rectangular waveguide is perpendicular to the tube axis of the circular waveguide. And the second rectangular waveguide has its tube axis oriented perpendicular to the tube axis of the circular waveguide and the tube axis of the first rectangular waveguide, respectively. Wave instrument. 2. A circular waveguide, a first rectangular waveguide connected through a first coupling hole provided at one end of the circular waveguide, and a tube of the circular waveguide. A second rectangular waveguide connected through a second coupling hole provided in a part of the wall, and the tube axis of the first rectangular waveguide is perpendicular to the tube axis of the circular waveguide. And the second rectangular waveguide has its tube axis oriented parallel to the tube axis of the first rectangular waveguide. 3. The demultiplexer according to claim 1, wherein the first coupling hole and the second coupling hole are formed at positions on the same plane of the circular waveguide. 4. A demultiplexer according to claim 3, wherein a filter for cutting off a signal wave propagating through the first rectangular waveguide is connected to the second rectangular waveguide. 5. A circular waveguide, a first rectangular waveguide connected through a first coupling hole provided at one end of the circular waveguide, and a tube of the circular waveguide. A second rectangular waveguide connected through a second coupling hole provided in a part of the wall, and the tube axis of the first rectangular waveguide is perpendicular to the tube axis of the circular waveguide. The second rectangular waveguide is oriented with its tube axis parallel to the tube axis of the first rectangular waveguide, and the first coupling hole and the second coupling hole are each in a circular waveguide. A demultiplexer characterized by being opened on a vertical surface.