6-port orthogonal mode junction

Abstract

A six-port orthogonal mode transducer suitable for additive manufacturing and capable of distinguishing between two frequency bands is provided. The present invention relates to a six-port orthomode transducer (1) manufactured by additive manufacturing, the transducer (1) comprising: a dual-polarized input port (10) and a dual-polarized output port (11), the input port and the output port defining a main direction (100) corresponding to the direction of propagation of a signal between the input port (10) and the output port (11); a first single polarization side port (12) extending along a first axis (120) intersecting the main direction (100); a second single-polarization side port (13) extending along a second axis (line 130) intersecting the main direction (100) and facing the first side port (12); a third single polarization side port (14) extending along a third axis (140) intersecting the main direction (100); a fourth single-polarization side port (15) extending along a fourth axis (150) intersecting the main direction (100) and facing the third side port (14); The transducer (1) has its first, second, third and fourth intersecting axes each forming an angle between 15° and 75° with respect to the main direction (100), characterized by a high-pass filter arranged between the side port and the output port and comprising at least two filtering slots (21). The invention also relates to such an orthogonal mode transducer and a transmit / receive antenna comprising a plurality of low-pass filters.

Description

Technical Field

[0001] The present invention relates to a 6-port orthogonal mode converter suitable for additive manufacturing.

Background Art

[0002] In the field of radio frequency transmission, a dual-polarized antenna is an antenna that can emit and receive electromagnetic waves according to two orthogonal polarization waves. These antennas generally consist of a radiating element (usually a horn type) and a feed chain. This feed chain must be able to distinguish particularly two orthogonal polarization waves, combine two signals during transmission, and separate the two signals respectively during reception. This discrimination can be achieved by a dipolar orthogonal mode converter (OMT) such as an input port connected to the horn and a "rotary" junction having two pairs of side ports arranged opposite to each other. Each pair enables one separation of polarization.

[0003] When such an antenna can additionally operate in dual band, that is, in two frequency bands, the feed chain must also be able to distinguish each frequency band. This discrimination is usually performed by a band-pass filter arranged in the feed chain.

[0004] Although the operations of polarization separation and combination and frequency filtering are completely different, certain orthogonal mode converters known in the prior art enable the combination of polarization and frequency discrimination in a single device. Such a device typically includes a total of six ports including an input port and an output port (usually arranged coaxially in dual polarization), and four side ports (usually in single polarization) respectively. Polarization discrimination is performed at the side ports, and frequency band discrimination can be performed using, for example, a high-pass filter connected to the output port and a low-pass filter connected to the side ports.

[0005] However, the recent rapid growth of additive manufacturing in the field of radio frequency transmission has increased the need to improve the design of such antennas so that they can be manufactured by additive manufacturing. In particular, orthogonal polarization antennas and orthogonal mode converters in general have relatively large cantilevered sections, such as parts of lateral waveguides or bandpass filters, making efficient and inexpensive additive manufacturing impossible. This is because the protruding sections must be supported during manufacturing, and then the support materials must be removed manually, resulting in losses of both time and money.

[0006] Patent Document 1 describes a 6-port quadrature mode converter capable of distinguishing two orthogonal polarizations propagating within a dominant wave tube by two pairs of rectangular cross-sectional side ports. The four side ports extend radially with respect to the main propagation direction of the signal within the dominant wave tube, i.e., perpendicular to this main propagation direction. A low-pass filter is connected to the port of the quadrature mode converter parallel to the main propagation direction, and four high-pass filters are connected to the four side ports. In this device, as mentioned above, the four side ports and low-pass filters are not suitable for additive manufacturing.

[0007] Non-patent document 1 describes a 6-port quadrature mode converter suitable for additive manufacturing. Frequency identification is achieved by a virtual filter, which is constructed by gradually narrowing the inner diameter of the lead wave tube, and also by a low-pass filter connected to the side ports. The side ports are oriented so that they form a connection with the input port, i.e., the port to be connected to the horn antenna, and the port with an H-plane divider. In other words, the longest side of the side port opening aligns with the direction of propagation. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] U.S. Patent Application Publication No. 2013 / 0342282 [Non-patent literature]

[0009] [Non-Patent Document 1] G. Addamo et al., “3D Printing of a Monolithic K / Ka-Band Dual-Circular Polarization Antenna-Feeding Network,” IEEE Access, vol. 9, pp. 88243-88255, 2021, DOI:10.1109 / ACCESS.2021.3089826 [Overview of the project] [Problems that the invention aims to solve]

[0010] One of the objectives of the present invention is to provide a 6-port quadrature mode converter that is not limited by the limitations of the prior art.

[0011] Another objective of this invention is to provide a 6-port quadrature mode converter suitable for additive manufacturing.

[0012] Another objective of this invention is to propose a 6-port quadrature mode converter capable of distinguishing between two frequency bands. [Means for solving the problem]

[0013] These objectives are achieved in particular by a 6-port quadrature mode converter manufactured by additive manufacturing. This 6-port quadrature mode converter is Dual-polarization input port, It has a dual-polarization output port, and the input port and output port define a main direction corresponding to the signal propagation direction between the input port and the output port, A first single-polarization side port extending along a first axis intersecting the aforementioned main direction, A second single-polarization side port facing the first side port, the second single-polarization side port extending along a second axis intersecting the main direction, A third single-polarization side port extending along a third axis intersecting the main direction, A fourth single-polarization side port facing the third side port, the fourth single-polarization side port extending along a fourth axis intersecting the main direction, comprising, In the six-port orthogonal mode converter, each of the first intersection axis, the second intersection axis, the third intersection axis, and the fourth intersection axis forms an angle between 15° and 75° with respect to the main direction, characterized by a high-pass filter disposed between the plurality of side ports and the output port and having at least two filtering slots.

[0014] The orthogonal mode converter may be characterized in that the high-pass filter comprises a platform extending radially from the main direction, and the at least two filtering slots may be provided in the platform.

[0015] The platform may comprise at least one support arch extending radially from the main direction.

[0016] To enable additive manufacturing of the converter, at least one support arch may comprise at least one cantilever beam surface forming an angle between 15° and 75° with respect to the main direction.

[0017] In the orthogonal mode converter, the relatively short dimension of each of the four side ports may be parallel to the main direction.

[0018] The output port may comprise at least one raised portion provided on its inner wall.

[0019] The platform may comprise a protruding impedance matching element extending in the main direction. !>

[0020] The diameter of the input port may be longer than the diameter of the output port.

[0021] The orthogonal mode converter may be characterized by the double symmetry along two planes orthogonal to each other, wherein the two orthogonal planes have the main direction.

[0022] The above-described plurality of objects are also achieved by an antenna for transmitting and / or receiving a dual-polarization signal, which includes the above-described orthogonal mode converter. This antenna includes four low-pass filters, and each side port is connected to one of the four low-pass filters.

[0023] Each of the four low-pass filters may include at least one serrated inner surface.

[0024] The antenna may be characterized by the double symmetry along two planes orthogonal to each other, wherein the two orthogonal planes have the main direction.

[0025] The plurality of embodiments of the present invention are represented and described by the following attached drawings.

Brief Description of the Drawings

[0026] [Figure 1] FIG. 1 shows a 3 / 4 perspective view (viewed from the front and obliquely) of a 6-port orthogonal mode converter. [Figure 2] FIG. 2 shows a longitudinal cross-section of a 6-port orthogonal mode converter. [Figure 3] FIG. 3 shows a longitudinal cross-section of a 6-port orthogonal mode converter. [Figure 4] FIG. 4 shows a top view of a 6-port orthogonal mode converter including a filtering platform. [Figure 5a] FIG. 5a shows a filtering platform suitable for additive manufacturing. [Figure 5b] FIG. 5b shows a top view of a filtering platform suitable for additive manufacturing. [Figure 6] FIG. 6 shows a longitudinal cross-section of a filtering platform suitable for additive manufacturing. [Figure 7] Figure 7 shows a side cross-section of a dual-polarization diplexer equipped with a 6-port orthogonal mode converter and a side filter with a notch on one side. [Figure 8] Figure 8 shows a side cross-section of a dual-polarization diplexer comprising a 6-port quadrature mode converter and side filters with notches on both sides. [Modes for carrying out the invention]

[0027] Figure 1 shows an orthogonal mode converter 1 according to the present invention, which has an input port 10 and an output port 11. A main direction 100 corresponding to the signal propagation direction between the input port and the output port is determined. Four side ports (12, 13, 14, 15) are connected to the orthogonal mode converter along four axes intersecting the main direction.

[0028] In this specification, the orthogonal mode converter of the present invention is defined as having a primary propagation direction between the input port 10 and the output port corresponding to the z-direction, and the z-direction coincides with the 3D printing direction. The x-direction and y-direction lie in a plane perpendicular to the z-direction and correspond to the orthogonal directions of each polarization.

[0029] The input port 10 is a standard waveguide with a circular or rectangular cross-section, capable of receiving and transmitting signals with circular, elliptical, or linear polarization. Generally, the cross-section of the input port may be any geometric shape deemed appropriate by those skilled in the art, including, for example, a pentagonal, hexagonal, polygonal cross-section with more than six sides, or a combination of polygonal cross-sections with curved sides. When used in a dual-polarization antenna, the input port 10 is typically connected to a waveguide or directly to an emitting element such as a horn. The output port 11 is positioned coaxially with the input port 10 and is also dual-polarized. Similarly, the output port 11 is a waveguide with any geometric shape deemed appropriate by those skilled in the art, including, for example, a pentagonal, hexagonal, polygonal sections with more than six sides, or a combination of polygonal sections with curved sides.

[0030] Between the input port 10 and the output port 11, there is a first side port 12 extending along a first axis 120 intersecting the main direction 100, and facing a second side port 13 extending along a second axis 130 intersecting the main direction 100. The first and second ports enable signal separation or coupling according to a first polarization P1. The third side port 14 extends along a third axis 140 intersecting the main direction 100 and faces a fourth side port 15 extending along a fourth axis 150 intersecting the main direction 100. The third and fourth ports enable signal separation or coupling according to a second polarization P2. Each of the four side ports is thus single-polarized.

[0031] In one embodiment shown in Figure 1, the side ports (12, 13, 14, 15) have a rectangular cross-section, and the shortest side of the rectangular cross-section is aligned with the main direction 100. As a result, a pair of side ports (i.e., corresponding to the same polarization) opposite the input port 10 form an E-plane divider or combiner. The direction of the electric field of a wave propagating through two side ports corresponding to the same polarization is therefore opposite.

[0032] As shown in Figure 3, the first, second, third, and fourth axes (120, 130, 140, and 150) each form an angle of 15° to 75°, preferably 35° to 55°, with respect to the main direction of 100°. This inclination with respect to the z-direction enables the addition of side ports. In fact, since the z-axis generally coincides with the 3D printing direction, the inclination of the side ports with respect to this direction reduces the physical constraints imposed by gravity on the side ports, thus reducing or even eliminating the need for supports during manufacturing. The inclination of the side ports allows for miniaturization by limiting the external volume of the orthogonal mode converter.

[0033] In one embodiment shown in Figure 4, the arrangement of the side ports (12, 13, 14, 15), and the input port 10 and output port 11, are such that the entire orthogonal mode converter 1 according to the present invention is aligned with two mutually orthogonal planes. One of these two symmetrical planes comprises the first axis and the second axis (120, 130) and the principal direction 100, The other symmetrical plane comprises the third and fourth axes (140, 150) and the principal direction 100. It has become that.

[0034] The orthogonal mode converter 1 according to the present invention includes a high-pass filter provided between the side port and the output port 11. This high-pass filter includes at least two filtering slots 21 for long wave rejection so that only short waves can pass through the output port 11.

[0035] In the context of this invention, the terms “high frequency” (“short wave”) and “low frequency” (“long wave”) may correspond to different ranges of values ​​depending on the embodiment. In fact, the present invention can be implemented in different devices targeting various frequency bands depending on its application. For example, the present invention can typically be used in devices targeting at least one or all of the X, Ku, Ka, QV, Ku / ka, and Ka / QV bands.

[0036] In the X-band, longwave frequencies are typically between 7.25 GHz and 7.75 GHz, while shortwave frequencies are between 7.9 GHz and 8.4 GHz.

[0037] In the Ku band, longwave typically ranges from 10.7 GHz to 12.75 GHz, and shortwave from 13.25 GHz to 4.5 GHz, or encompasses a partial range (segment) of these specific bands.

[0038] In the Ka band, longwave typically ranges from 17.3 GHz to 21.2 GHz, and shortwave from 27 GHz to 31 GHz, or encompasses a partial range of these specific bands.

[0039] In the QV band, longwave typically ranges from 37.5 GHz to 42.5 GHz, and shortwave ranges from 42.5 GHz to 52.5 GHz, or partial ranges of these specific bands.

[0040] In the Ku / Ka band, longwave typically spans between 10.7 GHz and 12.75 GHz, and shortwave between 13.25 GHz and 21 GHz, or partial ranges of these specific bands. Alternatively or complementaryly, longwave typically spans from 13.25 GHz to 21.2 GHz, shortwave from 13.25 GHz to 21.2 GHz, and very high frequency (VHF) from 27 GHz to 31 GHz, or partial ranges of these specific bands.

[0041] In the Ka / QV band, longwave typically ranges from 27 GHz to 42.5 GHz, and shortwave from 42.5 GHz to 52.5 GHz, or encompasses a partial range of these specific bands.

[0042] In one embodiment, the output port 11 has a cross-section with a smaller diameter than the cross-sectional diameter of the input port 10. This allows a portion of the input port's frequency band to correspond to a range below the output port's cutoff frequency. Therefore, this reduction in diameter allows for the addition of "virtual" filtering in addition to the high-pass filter.

[0043] For long waves, propagation occurs via the side ports (12, 13, 14, 15), which themselves can be connected to a low-pass filter to reject high frequencies.

[0044] In one preferred embodiment, the high-pass filter comprises a platform 20 on which filtering slots 21 are provided. The platform 20 extends radially around the principal direction. This platform is shown in Figure 3 and includes an upper surface facing the input port 10 and a lower surface facing the output port 11. Preferably, the upper surface of the platform is perpendicular to the principal direction 100.

[0045] The filtering slot 21 is formed on the one hand by the platform 20 and on the other hand by the inner wall of the output port 11. Alternatively or complementaryly, the filtering slot 21 is formed as a whole by the platform 20 in the sense that the sides of each slot are formed by a part of the platform.

[0046] In the embodiment shown in Figure 4, the platform 20 and the internal wall 110 of the output port 11 form four triangular filtering slots 21. The platform has four arms that extend from the main direction 100 toward the internal wall 110 of the output port 11.

[0047] The platform 20 may be provided with at least one support arch 22 to enhance the stability of the platform during additive manufacturing and / or while using the orthogonal mode converter. As shown in Figure 5a, the platform 20 may be provided with multiple support arches 22 that converge at the center of the platform in the principal direction.

[0048] To facilitate the additional manufacturing of the platform 20 and the support arch 22, the cantilever surface 220 of the support arch relative to the z-direction is axial Line Conversely, angles between 15° and 75° are advantageous, preferably between 35° and 55°. β Figure 6 shows a cross-sectional view of the platform in which the two support arches 220 form an angle β with respect to the principal direction 100. As with the side ports, from an additive manufacturing perspective, the optimal incline is approximately 45°. However, cantilevered surfaces with inclinations ranging from 15° to 75° are also possible, for reasons related to the internal geometry of the orthogonal mode converter, for example.

[0049] In one embodiment, a raised portion 23 parallel to the main direction may be provided on the inner surface of the output port 11. These raised portions allow, for example, an expansion of the frequency bandwidth and / or matching of the impedance of the output port 11. As shown in Figure 4, the coupling slot of the high-pass filter can divide the output port into a plurality of waveguides, and the raised portions 23 may be provided on the inner walls of these waveguides. The platform 20 can, for example, divide the output port 11 into four triangular waveguide portions, with one side of each portion corresponding to a side determined by the inner wall 110 of the output port, and the raised portion 23 is provided on that side.

[0050] The platform 20 may include a protruding impedance matching element 24. As shown in Figure 5a, this protruding element may extend from the platform 20 in the principal direction 100, so that the platform can function as a support for this protruding element during additive manufacturing.

[0051] A typical orthogonal mode converter 1 is used in a radio frequency antenna supply chain further comprising an antenna horn connected to the input port 11. Such an antenna also typically includes a low-pass filter 30 connected to the side ports (12, 13, 14, 15).

[0052] Figure 7 shows a cross-sectional view of one embodiment in which each side port is connected to a low-pass filter 30. The low-pass filter is, for example, a low-pass filter with a sawtooth pattern on its side walls. Each low-pass filter extends along the principal direction 100. These filters are advantageously symmetrical along the two symmetrical planes described above, namely, along the plane comprising the principal direction 100 and the first and second intersecting axes (120, 130), and also along the plane comprising the principal direction 100 and the third and fourth intersecting axes (140, 150). In this way, the orthogonal mode converter and low-pass filter assembly maintains double-plane symmetry.

[0053] Figure 8 shows one embodiment in which a low-pass filter 30 connected to a side port has two sawtooth-shaped internal walls. These filters 30 also extend along the principal direction 100. In this case as well, the double symmetry of the assembly of the orthogonal mode converter and the low-pass filter can be achieved.

[0054] In a supply chain comprising the low-pass filters and the orthogonal mode converter according to the present invention, the two pairs of low-pass filters corresponding to the first and second polarizations can then be recombined using two single-band combiners. In such a supply chain, the output port may be connected to a single-band orthogonal mode converter. Advantageously, the single-band combiners and the single-band orthogonal mode converter are also arranged to maintain the double symmetry of the supply chain. This application offers, for example, the following perspectives. [Perspective 1] A 6-port quadrature mode converter (1) manufactured by additive manufacturing, Dual polarization input port (10), The device comprises a dual-polarization output port (11), and the input port and the output port define a main direction (100) corresponding to the signal propagation direction between the input port (10) and the output port (11). A first single-polarization side port (12) extends along a first axis (120) that intersects the main direction (100), A second single-polarization side port (13) opposite the first side port (12), the second single-polarization side port (13) extending along a second axis (130) intersecting the main direction (100), A third single-polarization side port (14) extends along a third axis (140) that intersects the main direction (100), A fourth single-polarization side port (15) opposite the third side port (14), the fourth single-polarization side port (15) extending along a fourth axis (150) intersecting the main direction (100), In the 6-port orthogonal mode converter (1), each of the first, second, third, and fourth intersecting axes forms an angle between 15° and 75° with respect to the main direction (100), A 6-port orthogonal mode converter (1) characterized by a high-pass filter positioned between a plurality of side ports and the output port and having at least two filtering slots (21). [Perspective 2] The orthogonal mode converter (1) according to viewpoint 1, characterized in that the high-pass filter comprises a platform (20) extending radially from the principal direction (100), and the platform has at least two filtering slots (21). [Perspective 3] The orthogonal mode converter (1) according to viewpoint 2, wherein the platform (20) comprises at least one support arch (22) extending radially from the principal direction (100). [Perspective 4] The orthogonal mode converter (1) according to viewpoint 3, wherein the at least one support arch (22) comprises at least one cantilever beam (220) that forms an angle (β) between 15° and 75° with respect to the principal direction (100). [Perspective 5] An orthogonal mode converter (1) according to any one of viewpoints 1 to 4, characterized in that the relatively shorter dimension of each of the four side ports (12, 13, 14, 15) is parallel to the principal direction (100). [Perspective 6] The orthogonal mode converter (1) according to any one of views 1 to 5, wherein the output port (11) comprises at least one protrusion (23) provided on the inner wall (110) of the output port (11). [perspective 7] An orthogonal mode converter (1) according to any one of views 2 to 5 and view 6, which references view 2, wherein the platform (20) comprises a protruding impedance matching element (24). [Perspective 8] The orthogonal mode converter (1) according to any one of viewpoints 1 to 7, wherein the diameter of the input port (10) is longer than the diameter of the output port (11). [Perspective 9] An orthogonal mode converter (1) according to any one of viewpoints 1 to 8, characterized by a double symmetry along two mutually orthogonal planes, wherein the two orthogonal planes comprise the principal direction (100). [Perspective 10] An antenna for both or one of the transmission and reception of dual-polarized signals, comprising an orthogonal mode converter (1) as described in any one of viewpoints 1 to 9, The antenna comprises four low-pass filters (30), with each side port (12, 13, 14, 15) connected to one of the four low-pass filters (30). [Perspective 11] The antenna according to viewpoint 10, wherein each of the four low-pass filters (30) has at least one inner surface with multiple jagged edges. [Perspective 12] An antenna according to viewpoint 10 or 11, characterized by a double symmetry along two mutually orthogonal planes, wherein the two orthogonal planes comprise the principal direction (100). [Explanation of symbols]

[0055] 1. Orthogonal mode converter 10 input ports 100 Main direction 11 output ports 110 Inner wall of output port 12. First side port 13. Second side port 14 Third side port 15. Fourth side port 120 First Intersecting Axis 130 Second Intersecting Axis 140 Third Intersecting Axis 150 Fourth Intersecting Axis 20 platforms 21 filter grooves 22 Support arch 220 Cantilevered surface 23 Ridge 24 Protruding impedance matching element 30 Low-pass filters

Claims

1. A six-port quadrature mode converter (1) manufactured by additive manufacturing, Dual polarization input port (10), The device comprises a dual-polarization output port (11), and the input port and the output port define a main direction (100) corresponding to the signal propagation direction between the input port (10) and the output port (11). A first single-polarization side port (12) extends along a first intersecting axis (120) that intersects the main direction (100), A second single-polarization sideport (13) opposite to the first single-polarization sideport (12), the second single-polarization sideport (13) extending along a second intersecting axis (130) that intersects the main direction (100), A third single-polarization side port (14) extends along a third intersecting axis (140) that intersects the main direction (100), A fourth single-polarization sideport (15) opposite to the third single-polarization sideport (14), the fourth single-polarization sideport (15) extending along a fourth intersecting axis (150) that intersects the main direction (100), In the six-port orthogonal mode converter (1), each of the first, second, third, and fourth intersecting axes forms an angle between 15° and 75° with respect to the main direction (100), A high-pass filter is disposed between all of the first single-polarization sideport, the second single-polarization sideport, the third single-polarization sideport, and the fourth single-polarization sideport and the output port, At least two filtering slots (21), A platform (20) is provided with at least two filtering slots (21) and extends radially from the main direction (100). It features a high-pass filter equipped with, The platform (20) further comprises an impedance matching element (24) that extends and protrudes along the main direction (100). A 6-port orthogonal mode converter (1).

2. The orthogonal mode converter (1) according to claim 1, wherein the platform (20) comprises at least one support arch (22) extending radially from the principal direction (100).

3. The orthogonal mode converter (1) according to claim 2, wherein the at least one support arch (22) comprises at least one cantilever beam (220) that forms an angle (β) between 15° and 75° with respect to the principal direction (100).

4. The orthogonal mode converter (1) according to claim 1, characterized in that each of the first single-polarization sideport (12), the second single-polarization sideport (13), the third single-polarization sideport (14), and the fourth single-polarization sideport (15) has a rectangular cross-section, and the short side of the rectangular cross-section is aligned with the principal direction.

5. The orthogonal mode converter (1) according to claim 1, wherein the output port (11) comprises at least one raised portion (23) provided on the inner wall (110) of the output port (11).

6. The orthogonal mode converter (1) according to claim 1, wherein the diameter of the input port (10) is longer than the diameter of the output port (11).

7. The orthogonal mode converter (1) according to claim 1, characterized by a double symmetry along two mutually orthogonal planes, wherein the two orthogonal planes comprise the principal direction (100).

8. An antenna for both or one of the transmission and reception of a dual-polarization signal, comprising the quadrature mode converter (1) described in claim 1, The antenna comprises four low-pass filters (30), with each side port (12, 13, 14, 15) connected to one of the four low-pass filters (30).

9. The antenna according to claim 8, wherein each of the four low-pass filters (30) comprises at least one of a plurality of jagged inner surfaces.

10. The antenna according to claim 8, characterized by a double symmetry along two mutually orthogonal planes, wherein the two orthogonal planes include the principal direction (100).

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