JPH0261162B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an antenna feeding system used in a communication system in which two frequency signals are used and each signal is orthogonally polarized. Concerning a waveguide type orthogonal polarization splitter.

[Conventional technology]

In general, circular main waveguides are widely used as waveguides that transmit signals in two frequency bands with two polarized waves orthogonal to each other and with each polarized wave.
The diameter of the circular waveguide used to demultiplex each signal is selected so that only the TE ₁₁ mode, which is the fundamental mode of the circular waveguide, propagates in the frequency band to be demultiplexed. Conventionally, when the difference between two frequencies is large, it is possible to select the optimum waveguide diameter for demultiplexing in each band. It was installed by taking advantage of the blocking characteristics due to the difference in wave tube diameter. on the other hand,
When the frequency difference between two frequency bands is small, a waveguide with sufficient blocking characteristics for demultiplexing cannot be used, so a polarization demultiplexer as shown in FIG. 2 is used. In this method, a part of the circular main wave tube 3 has a filter 15 structure, and the cutoff characteristics of the filter 15 are used to branch out. As another example, as shown in Fig. 3, vertical polarization 1, horizontal polarization 2
is split across two frequency bands at once, and then frequency splitting is performed for each polarization using another splitter 17, 17 to obtain the desired horizontal and vertical polarizations 7, 10, Some get 11 or 12.

[Problem that the invention seeks to solve]

As mentioned above, in the case where the frequency difference between two frequency bands is small, the orthogonal polarization branching filter shown in FIG. The composition circuit 14 must be used for the rectangular sub-waveguide, which not only complicates the structure, but also
It is difficult to manufacture the filter 15 having a circular waveguide section.

On the other hand, in the branching filter shown in FIG. It is necessary to separate the signals in the frequency band, which makes the configuration complicated.

[Means for solving problems]

As a means for solving the above-mentioned problems, the orthogonal polarization splitter of the present invention includes a circular main waveguide that transmits signals in two frequency bands, first and second, into two mutually orthogonal polarized waves, respectively. , two sets of orthogonal conductor thin plates (or a plurality of conductor bars) are placed apart in the tube axis direction, and are perpendicular to the conductor thin plate surface in the circular main wave tube that is approximately λg _1/4 away from the end of each conductor thin plate. A first coupling hole for the first frequency band is provided on one wall surface on a plane, and a coupling hole for the second frequency band is provided on the circular main waveguide wall surface facing the first coupling hole at a distance of about λg ₂ /4. A total of four second coupling holes are provided, a filter for reflecting a signal in a second frequency band is provided in the sub waveguide connected to the first coupling hole, and a filter for reflecting a signal in a second frequency band is provided in the second coupling hole. A filter for reflecting signals in the first frequency band is provided in the connected sub-waveguide.

Here, λg ₁ and λg ₂ indicate the wavelengths within the circular main waveguide of the signals in the first and second frequency bands, respectively.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows one embodiment of the present invention. The configuration includes two orthogonal conductor thin plates (or a plurality of conductor bars) 4, 4 provided as electrically equivalent blocking surfaces on the circular main wave pipe 3, and two conductor thin plates 4, 4 provided on the wall surface of the circular main wave pipe 3. It consists of four coupling holes 5, 8, and four filters 6, 9 provided in each sub-waveguide connected to the respective coupling holes, for blocking unnecessary waves.

Here, if the channel wavelengths of the signals in the first frequency band and the second frequency band are λg ₁ and λg ₂ , respectively,
As shown in the figure, the coupling holes 5 and 8 are provided at positions λg ₁ /4 and λg ₁ /4 from the ends of the thin conductor plates 4 and 4, respectively.

The vertically polarized wave 1 and the horizontally polarized wave 2 are guided to the rectangular sub-waveguide through coupling holes 5 and 8 by thin conductor plates 4 and 4 which are electrically equivalent blocking surfaces. Unnecessary waves are blocked by filters 6 and 9, and desired horizontal and vertical polarized waves 7, 10, 11, and 12 can be separated independently.

In addition, when providing conductor rods in place of the thin conductor plate 4 inside the circular main waveguide 3, four to five or more conductor rods may be provided so as to be on the same plane or more as the thin conductor plate 4 and extend in the diametrical direction. good.

〔Effect of the invention〕

As explained above, the present invention provides a circular main waveguide with two orthogonal conductor thin plates (or a plurality of conductor bars).
By providing four coupling holes on the wall of the circular main waveguide and installing a filter in each coupling hole to cut out unnecessary waves, the structure is simple without the need for a combining circuit or separate splitter. This has the effect of being able to separate signals in two frequency bands at once, each of which has orthogonal polarization.

[Brief explanation of drawings]

FIG. 1 shows a perspective view of an embodiment of an orthogonal polarization splitter according to the present invention, and FIGS. 2 and 3 each show a perspective view of a conventional orthogonal polarization splitter. In the figure, 3...Circular main wave tube, 4...Thin conductor plate, 6...Second frequency band blocking rectangular filter, 9
...First frequency band blocking rectangular filter.

Claims (1)

[Claims] 1. A circular main wave tube that simultaneously transmits signals in two frequency bands, first and second, in two linearly polarized waves orthogonal to each other, and the circular main wave tube via a coupling hole. In an orthogonally polarized waveguide consisting of four rectangular sub-waveguides connected to the circular main waveguide, two sets of orthogonal conductor thin plates (or a plurality of conductor bars) are spaced apart in the tube axis direction. approximately 1/4 from the end of each thin conductor plate. λg ₁ (where λg ₁ is the internal wavelength of the circular waveguide of the signal in the first frequency band) A first A first coupling hole dedicated to the frequency band is provided, and the diameter is approximately 1/4. λg ₂ (where λg ₂ is the internal wavelength of the circular waveguide of the second frequency band signal) a second coupling hole is provided in the wall surface of the circular main waveguide facing away from the first coupling hole; A filter for reflecting the second frequency band signal is provided in the sub waveguide connected to the first coupling hole, and a filter for reflecting the second frequency band signal is provided in the sub waveguide connected to the second coupling hole. An orthogonal polarization splitter characterized by being provided with a filter that reflects.