Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
  • H01P1/00—Auxiliary devices
  • H01P1/16—Auxiliary devices for mode selection, e.g. mode suppression or mode promotion; for mode conversion
  • H01P1/161—Auxiliary devices for mode selection, e.g. mode suppression or mode promotion; for mode conversion sustaining two independent orthogonal modes, e.g. orthomode transducer

Definitions

• the present invention relates to a six-port orthomode transducer suitable for additive manufacturing.
• dual polarization antennas are antennas capable of transmitting as well as receiving electromagnetic waves according to two orthogonal polarizations.
• These antennas generally consist of a radiating element (typically horn type) and a feed chain.
• This power supply chain must in particular allow discrimination of the two orthogonal polarizations so as to be able to combine (in transmission), respectively separate in reception, the two signals.
• This discrimination can be carried out via an orthomode transducer with the English acronym "OMT”) with double polarization such as a "turnstile" junction having an input port connected to the horn and two pairs of lateral ports placed there. 'one facing the other, each pair making it possible to isolate one of the polarizations.
• OMT orthomode transducer
• double polarization such as a "turnstile" junction having an input port connected to the horn and two pairs of lateral ports placed there. 'one facing the other, each pair making it possible to isolate one of the polarizations.
• the power supply chain must also be capable of discriminating the respective frequency ranges. This discrimination is usually carried out via band-pass filters placed in the supply chain.
• Document US2013/0342282 A1 describes a six-port orthomode transducer in which two pairs of lateral ports with a rectangular section make it possible to discriminate between the two orthogonal polarizations of a wave propagating in a main waveguide.
• the four lateral ports extend radially relative to the main propagation direction of the signal in the main guide, that is to say perpendicular to this main propagation direction.
• a low-pass filter is connected to one port of the orthomode transducer whose direction is parallel to the main propagation direction, while four high-pass filters are connected to the four side ports.
• the four side ports as well as a low-pass filter as described are not suitable for additive manufacturing for the reasons mentioned above.
• Addamo et al. “3D Printing of a Monolithic K/Ka-Band Dual-Circular Polarization Antenna-Feeding Network,” in IEEE Access, vol. 9, pp. 88243-88255, 2021 describes a six-port orthomode transducer suitable for additive manufacturing.
• Frequency discrimination is carried out on the one hand by a virtual filter consisting of a progressive narrowing of the internal diameter of the main waveguide and on the other hand by low-pass filters connected to the side ports.
• the side ports are oriented so that two pairs of side ports form with the input port, that is to say the port intended to be connected to the antenna horn, a divider in the H plane. In other words, the longer side of the opening of the side ports is aligned with the direction of propagation.
• Another aim of the invention is to propose a six-port orthomode transducer suitable for additive manufacturing.
• Another aim of the invention is to propose a six-port orthomode transducer making it possible to discriminate between two frequency bands.
• a six-port orthomode transducer produced by additive manufacturing, and comprising a dual polarization input port; a dual polarization output port; the input port and the output port defining a main direction corresponding to the direction of propagation of a signal between the input port and the output port; a first side port with single polarization extending along a first axis transverse to the main direction; a second side port with single polarization facing the first side port and extending along a second axis transverse to the main direction; a third side port with single polarization extending along a third axis transverse to the main direction; a fourth side port with single polarization facing the third side port and extending along a fourth axis transverse to the main direction; said first, second, third and fourth transverse axes each forming an angle with the main direction of between 15° and 75°, the six-port orthomode transducer being characterized by a high-pass filter disposed
• the orthomode transducer can be characterized in that said high-pass filter comprises a platform extending radially from the main direction, the at least two filtering slots being arranged on said platform.
• the platform may include at least one support arch extending radially from the main direction.
• the orthomode transducer can be characterized in that a smallest dimension of each of the four side ports is parallel to the main direction.
• the outlet port may comprise at least one groove arranged on an internal wall of the outlet port.
• the platform may include a salient impedance matching element extending in the main direction.
• an antenna for the transmission and/or reception of dual polarization signals comprising an orthomode transducer as described above and comprising four low-pass filters, each port side being connected to one of the four low-pass filters.
• the antenna can be characterized by double symmetry along two mutually orthogonal planes, each of the two orthogonal planes comprising the main direction.
• Figure 3 illustrates a longitudinal section of a six-port orthomode transducer.
• Figure 7 illustrates a side section of a dual polarization diplexer comprising a six-port orthomode transducer and lateral filters crenellated on one face.
• Figure 8 illustrates a side section of a dual polarization diplexer comprising a six-port orthomode transducer and lateral filters crenellated on two faces.
• the orthomode transducer of the present invention is oriented in the following manner: the main direction of propagation between the input port 10 and the output port corresponds to the direction z which coincides with the 3D printing direction.
• the x and y directions lie in a plane orthogonal to the z direction and correspond to the orthogonal directions of the polarizations.
• the input port 10 consists of a standard waveguide whose section can be circular or rectangular so as to receive/transmit signals with circular, elliptical or linear polarization.
• the section of the entry port can be any geometric shape deemed suitable by those skilled in the art, this including for example pentagonal, hexagonal, polygonal sections with more than six sides, but also combinations of sections of polygons with curved sides.
• input port 10 is typically connected to a waveguide or directly to a radiating element such as a horn.
• the output port 11 is, for its part, arranged coaxially with the input port 10 and is also double polarized.
• the side ports (12,13,14,15) are of rectangular section with the smallest side of the rectangular sections aligned with the main direction 100, so that the combination of input port 10 with a pair of opposite side ports (i.e. corresponding to the same polarization) forms a divider/combiner according to plane E.
• the direction of the electric field of a wave propagated in the two ports lateral corresponding to the same polarization is therefore opposite.
• each of the first, second, third and fourth axes forms an angle with the main direction 100 of between 15° and 75°, preferably between 35° and 55°.
• This inclination relative to the z direction makes additive manufacturing of the side ports possible.
• the z axis generally coincides with the 3D printing direction, thus, the inclination of the side ports relative to this direction makes it possible to reduce the physical constraints exerted by the force of gravity on these side ports and therefore makes it possible to reduce or even eliminate the need for supports during manufacturing.
• the inclination of the side ports can also increase the compactness of the orthomode transducer by limiting its external volume.
• the orthomode transducer 1 of the present invention is provided with a high-pass filter disposed between the side ports and the output port 11.
• This high-pass filter comprises at least two filtering slots 21 making it possible to reject the bass frequencies so that only high frequencies can pass through output port 11.
• the terms “high frequency” and “low frequency” can correspond to different ranges of values depending on the embodiment of the invention. Indeed, the present invention can be implemented in different devices intended for various frequency bands depending on their applications. By way of examples, the present invention can typically be used in devices intended for the X, Ku, Ka, QV, Ku/ka, and/or Ka/QV bands.
• low frequencies are typically between 7.25GHz and 7.75GHz and high frequencies between 7.9GHz and 8.4GHz.
• low frequencies are typically between 10.7GHz and 12.75GHz and high frequencies between 13.25GHz and 4.5GHz, or subportions of these particular bands.
• low frequencies are typically between 17.3 GHz and 21.2 GHz and high frequencies between 27 GHz and 31 GHz, or subportions of these particular bands.
• the low frequencies are typically between 37.5 GHz and 42.5 GHz and the high frequencies between 42.5 GHz and 52.5 GHz, or sub-portions of these particular bands.
• low frequencies are typically between 10.7GHz and 12.75GHz and high frequencies between 13.25GHz and 21GHz, or sub-portions of these particular bands; alternatively, or additionally, low frequencies are typically between 13.25GHz and 21.2GHz and high frequencies between 13.25GHz and 21.2GHz and high frequencies between 27GHz and 31GHz or subportions of these particular bands.
• FIG. 4 In the embodiment illustrated in Figure 4, four triangular filtering slots 21 are formed by the platform 20 on the one hand and the internal walls 110 of the outlet port 11.
• the platform comprises four arms extending from the main direction 100 towards the internal walls 110 of the outlet port 11.
• the platform 20 may include at least one support arch 22 so as to reinforce the stability of the platform during additive manufacturing and/or during use of the orthomode transducer. As illustrated in Figure 5a, the platform 20 can include several support arches 22 meeting in the center of the platform at the level of the main direction.
• the overhanging faces 220 of the support arches with respect to the z direction form an angle REF with the axis (z). advantageously between 15° and 75°, preferably between 35° and 55°.
• Figure 6 illustrates a sectional view of the platform in which two support arches 220 form an angle p with the main direction 100.
• the optimal inclination in terms of additive manufacturing is around 45°.
• inclinations of the cantilever faces of between 15° and 75° may also be relevant.
• streaks 23 parallel to the main direction can be arranged on the internal surface of the output port 11.
• the coupling slots of the high pass filter can divide the output port into a plurality of waveguides on an inner wall of which a streak 23 can be arranged.
• the platform 20 can for example divide the output port 11 into four waveguides of triangular sections, one side of each section corresponding to the side determined by an internal wall 110 of the output port being provided with a groove 23.
• the platform 20 can also include a projecting impedance matching element 24. As illustrated in Figure 5a, this projecting element can extend in the main direction 100 from the platform 20, the platform can thus serve as a support of the protruding element during additive manufacturing.
• the orthomode transducer 1 is typically used in the power supply chain of a radio frequency antenna further comprising an antenna horn connected to the input port 11.
• a radio frequency antenna further comprising an antenna horn connected to the input port 11.
• Such an antenna also generally includes low pass filters 30 connected to the side ports (12,13,14,15).

Landscapes

• Waveguide Aerials (AREA)
• Control Of Motors That Do Not Use Commutators (AREA)
• Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=84819848

Family Applications (1)

Country Status (8)

Family Cites Families (9)

• 2022
  • 2022-09-01 FR FR2208770A patent/FR3139418B1/fr active Active
• 2023
  • 2023-08-31 WO PCT/IB2023/058616 patent/WO2024047573A1/fr not_active Ceased
  • 2023-08-31 JP JP2025507551A patent/JP2025526083A/ja active Pending
  • 2023-08-31 CN CN202380062811.1A patent/CN119790544A/zh active Pending
  • 2023-08-31 CA CA3262566A patent/CA3262566A1/en active Pending
  • 2023-08-31 KR KR1020257010282A patent/KR20250056264A/ko active Pending
  • 2023-08-31 IL IL318726A patent/IL318726A/en unknown
  • 2023-08-31 EP EP23765322.5A patent/EP4581702A1/de active Pending

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