Waveguide array having a trapezoidal cross-section
Patent Information
- Application Number
- EP2024712306
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-03-13
- Filing Date
- 2024-03-11
- Publication Date
- 2026-01-21
AI Technical Summary
Existing radio frequency waveguide networks face challenges in compactness, weight reduction, and additive manufacturing feasibility due to limitations in geometry, particularly with rectangular and hexagonal cross-sections, which lead to difficulties in printing and increased assembly steps and costs.
A waveguide network with trapezoidal sections, where each pair of waveguides shares a common wall, optimizing space usage and reducing cantilevered surfaces during printing, allowing for more design freedom and reduced weight, achieved through additive manufacturing.
The trapezoidal waveguide network achieves compactness, reduced weight, and simplified manufacturing by eliminating cantilevered surfaces and shared walls, enabling efficient additive manufacturing and minimizing assembly steps, resulting in a denser and lighter waveguide array.
Smart Images
Figure IB2024052336_19092024_PF_FP_ABST
Abstract
Description
Trapezoidal waveguide array Technical field
[0001] The present invention relates to a trapezoidal cross-section waveguide array and an antenna array comprising such a waveguide array. State of the art
[0002] Radio frequency waveguide arrays are widely used in many areas of telecommunications, particularly in the field of satellite telecommunications.
[0003] Constraints related to the payload of satellites limit the space and weight available for all onboard elements, including the constituent elements of antennas and other passive radio frequency devices.
[0004] Additive manufacturing of such devices offers the advantage of creating complex geometries, optimizing the space occupied by the devices, and employing a manufacturing method requiring very few assembly steps, thus reducing both manufacturing time and cost. However, additive manufacturing also has certain constraints, particularly regarding device geometry, to be feasible.
[0005] There is therefore a need for passive radio frequency devices whose compactness is optimized, whose weight is reduced to a minimum and whose geometry is adapted for additive manufacturing.
[0006] There is also a need for alternative waveguide array geometries, in order to offer the designer greater design freedom.
[0007] Waveguide arrays often consist of matrix arrangements of waveguides with rectangular cross-sections, or honeycomb arrangements of waveguides with hexagonal cross-sections. In these arrangements, each waveguide, except those at the edge of the array, shares all its walls with adjacent waveguides. This sharing of walls reduces the weight and size of the array.
[0008] Additive manufacturing of waveguide arrays with rectangular or hexagonal cross-section is, however, difficult, due to the number of cantilevered walls during printing.
[0009] Arrays of circular waveguides arranged in a matrix have also been conceived. In this arrangement, each waveguide shares only a very limited length of its contour with its neighbors, for example, four points. The ratio between the channel area and the wall area is therefore unfavorable. Brief summary of the invention
[0010] One aim of the present invention is to provide a waveguide network free from the limitations present in the prior art.
[0011] Another aim of the invention is to provide a network of waveguides facilitating its additive manufacturing.
[0012] Another aim of the invention is to provide a network of waveguides that allows for limiting the assembly steps during its manufacture.
[0013] Another aim of the invention is to provide a waveguide network with optimized compactness.
[0014] Another objective of the invention is to provide a waveguide array that is lighter than prior art waveguide arrays.
[0015] According to the invention, these goals are achieved in particular by means of a waveguide network obtained by additive manufacturing comprising waveguides arranged two by two so as to form at least one pair of waveguides, each pair of waveguides comprising: a first waveguide of trapezoidal cross-section of which at least one of the angles is different from 90°, and; a second waveguide of trapezoidal cross-section of which at least one of the angles is different from 90°; characterized in that the first waveguide and the second waveguide have a common wall.
[0016] The trapezoidal shape with at least one angle other than 90° allows for the reduction or elimination of horizontal overhanging surfaces during printing.
[0017] The trapezoidal section is that of the waveguide channel.
[0018] According to one embodiment, the common wall corresponds to a small base of the trapezoidal sections of the first and second waveguides.
[0019] According to one embodiment, the common wall corresponds to a large base of the trapezoidal sections of the first and second waveguides.
[0020] According to one embodiment, the common wall corresponds to a side adjacent to the bases of the trapezoidal sections of the first and second waveguides.
[0021] The first waveguide can be arranged to transmit a first polarization, and the second waveguide can be arranged to transmit a second polarization.
[0022] The first waveguide can be arranged to transmit a first polarization, and the second waveguide can be arranged to transmit the same first polarization.
[0023] According to one embodiment, the number of waveguides is greater than or equal to four so as to form at least two pairs of waveguides, the common wall of the waveguides of a first pair corresponds to the small base of the trapezoidal sections and the common wall of the waveguides of a second pair corresponds to the large base of the trapezoidal sections.
[0024] According to one embodiment, the number of waveguides is greater than or equal to four and the pairs of waveguides are arranged contiguously along a first direction such that two successive pairs along the first direction have at least one waveguide wall in common.
[0025] According to one embodiment, the number of waveguides is greater than or equal to four and the pairs of waveguides are arranged contiguously in a first direction and in a second direction, such that two successive pairs in the first direction have at least one waveguide wall in common and such that two successive pairs in the second direction have at least one waveguide wall in common.
[0026] According to one embodiment, at least one wall of waveguides common to successive pairs along the first direction corresponds to a base of the trapezoidal sections of the waveguides and at least one wall of waveguides common to successive pairs along the second direction corresponds to a side adjacent to the bases of the trapezoidal sections of the waveguides.
[0027] According to one embodiment, an inner wall of the first waveguide and an inner wall of the second waveguide comprise a groove.
[0028] According to one embodiment, two internal walls of the first waveguide and two internal walls of the second waveguide comprise a groove.
[0029] According to one embodiment, the two internal walls with grooves correspond to the bases of the trapezoidal section of the first and second waveguides.
[0030] According to one embodiment, each trapezoidal section is an isosceles trapezoid or a parallelogram.
[0031] According to one embodiment, the waveguide network is adapted to function as a combiner network.
[0032] These goals are also achieved by means of a dual-polarization antenna array obtained by additive manufacturing comprising: a waveguide array according to one of the preceding claims, a plurality of radiating elements, each radiating element being coupled to the end of exactly one pair of waveguides of the array.
[0033] According to one embodiment of the antenna array, the waveguide array comprises at least eight waveguides and the pairs of waveguides are arranged contiguously in a first direction and in a second direction, such that two successive pairs in the first direction have at least one waveguide wall in common and such that two successive pairs in the second direction have at least one waveguide wall in common.
[0034] The invention may also relate to a waveguide array for transmitting a single polarization, comprising several lines (or slices) of waveguides, each line including power combiners, angled waveguides, and straight sections, wherein the straight waveguides of each line have trapezoidal cross-sections, the waveguides of each line being alternately in a first orientation and in a second head-to-tail orientation with respect to the first orientation, such that each waveguide within each line shares a side adjacent to the bases of the trapezoid with the neighboring waveguide in the line. The array may comprise several lines, the trapezoidal bases of adjacent lines being shared.
[0035] The invention may also relate to a waveguide array for transmitting two polarizations, comprising at least one line (or slice) of waveguides for transmitting a first-polarization signal and at least one second line (or slice) of waveguides for transmitting a second-polarization signal, each line comprising power combiners, angled waveguides, and straight sections, wherein the straight waveguides of each line have trapezoidal cross-sections, the waveguides of each line being alternately in a first orientation and in a second head-to-tail orientation with respect to the first orientation, such that each waveguide within each line shares a side adjacent to the bases of the trapezoid with the neighboring waveguide in the line. The trapezoidal bases of adjacent lines may be shared. Brief description of the figures
[0036] Examples of implementation of the invention are given in the description illustrated by the accompanying figures, in which: • Figures 1a and 1b schematically illustrate two cross-sectional views of a pair of trapezoidal waveguides. • Figure 2a schematically illustrates two cross-sectional views of waveguide arrays arranged along one direction. • Figure 3 schematically illustrates a cross-sectional view of a waveguide array arranged in two directions. • Figure 4 illustrates a cross-sectional view of an antenna array comprising a trapezoidal waveguide array. • Figure 5 illustrates a perspective cross-section of an antenna array comprising a trapezoidal waveguide array. • Figure 6 illustrates a perspective view of an antenna array comprising a waveguide array according to the present invention. Example(s) of embodiment of the invention
[0037] The present invention relates firstly to a network of waveguides in which the cross-section of each waveguide is trapezoidal, with at least one angle other than 90°. In other words, the geometric profile obtained by intersecting the waveguide with a plane essentially perpendicular to the direction of wave propagation in the waveguide is a trapezoid, that is to say, a quadrilateral having at least one pair of parallel sides, called the bases of the A trapezoid, where at least one of the angles is not 90°. A trapezoid has a smaller base and a larger base.
[0038] A trapezoidal section with at least one angle other than 90° excludes all rectangular and square sections. However, a parallelogram-shaped section with at least one angle other than 90° is covered by this definition. For the remainder of this text, it will be understood that the term "trapezoidal section" means "a trapezoidal section with at least one angle other than 90°."
[0039] The waveguide array preferably comprises an even number of waveguides. The waveguides in the array can be arranged in pairs to form pairs of 12 waveguides. Each pair 12 of waveguides comprises a first waveguide 10 for propagating an electromagnetic wave with a first polarization P1 and a second waveguide 11 for propagating an electromagnetic wave with a second polarization P2. Thus, each pair of waveguides can support two polarizations. These pairs are characterized in that the waveguides that form them share a wall 100. This shared wall corresponds to a base of the trapezoidal sections of each waveguide, or to a side adjacent to the bases.
[0040] It is also possible to provide a network of the type described in this description, but in which each waveguide transmits the same polarization.
[0041] As illustrated in Figures 1a and 1b, the common wall 100 of the first waveguide 10 and the second waveguide 11 can correspond to the larger base of the trapezoidal section or to the smaller base of the trapezoidal section. The common wall can also correspond to a side adjacent to the bases of the trapezoidal sections.
[0042] In an embodiment illustrated in Figures 2a and 2b, the waveguide array 1 comprises a plurality of pairs 12 of trapezoidal waveguides arranged in one direction. Two successive pairs share at least one waveguide wall. In other words, a waveguide of a first pair shares a wall with a waveguide of a second pair.
[0043] In an embodiment illustrated in Figure 2a, a plurality of pairs 12 consisting of pairs of waveguides sharing a large base of the trapezoidal section can be arranged along a direction X. Two successive pairs can share a wall of waveguides corresponding to a small base of the trapezoidal section as illustrated in Figure 2a or corresponding to a large base (not shown).
[0044] In an embodiment illustrated in Figure 2b, a plurality of pairs 12 consisting of pairs of waveguides sharing between them a small or a large base of the trapezoidal section can be arranged along a direction Y. Two successive pairs share two waveguide walls corresponding to sides adjacent to the bases of the trapezoidal sections.
[0045] In an embodiment illustrated in Figure 3, a plurality of pairs 12 consisting of pairs of waveguides (10,11) sharing between them a small or a large base of their trapezoidal section can be arranged along a first direction X and a second direction Y. The resulting network 1 consists of a matrix of waveguides with a trapezoidal section.
[0046] These arrangements make it possible to obtain dense and compact waveguide arrays. Indeed, the trapezoidal shape of the cross-sections allows for optimal use of space by eliminating any gaps between adjacent waveguides. Furthermore, the sharing of walls between some adjacent waveguides allows for This reduces the overall weight of the network since some walls are shared. The shared walls therefore serve two waveguides simultaneously.
[0047] In one embodiment, at least one internal wall of the waveguides is provided with a groove. The groove(s) allow, in particular, for the miniaturization of the array and / or promote the transmission of certain modes by limiting higher-order modes. The groove(s) can be located on any internal wall of the waveguides. Grooves within the same waveguide can be identical or have different geometries.
[0048] The trapezoidal waveguides described can be straight or angled. It is also possible to incorporate combiners, such as Y-shaped or H-shaped combiners, with multiple branches of the same trapezoidal cross-section.
[0049] In an embodiment illustrated in Figure 4, the waveguides of the array are provided with several grooves. In particular, the waveguides include a groove on the small base of the trapezoidal section and a groove on the large base of the trapezoidal section.
[0050] The groove walls can be adapted to facilitate additive manufacturing. For example, the angles between the groove walls and the printing direction can be adjusted to minimize overhanging sections. Alternatively, or additionally, the grooves can include rounded sections to further facilitate additive printing.
[0051] The present invention also relates to a dual-polarization antenna array 2 obtained by additive manufacturing and including a waveguide array 1 as described above and a plurality of radiating elements coupled to the pairs 12 of waveguides.
[0052] In an embodiment illustrated in Figure 5, each radiating element is connected to a pair 12 of waveguides so as to emit or receive a dual-polarization signal (P1,P2), the first waveguide 10 of the pair 12 propagating the first polarization P1 and the second waveguide 11 of the pair 12 propagating the second polarization P2.
[0053] In an embodiment not shown, each radiating element is connected to a single waveguide.
[0054] The connection between a radiating element and a waveguide, or a pair of waveguides, may include one or more section adapters, for example if the section of the radiating elements is circular, rectangular or more generally non-trapezoidal.
[0055] The antenna array shown in Figure 5 can be combined with a plurality of identical arrays to form a matrix array. The trapezoidal shape of the waveguide cross-sections allows for a dense and compact array by minimizing the free space between the antenna arrays. Such a matrix array is illustrated in Figure 6.
[0056] Additive manufacturing is particularly well-suited for producing such waveguide and antenna arrays. It allows for optimized density of the various waveguide arrays. Furthermore, it drastically reduces manufacturing time and cost. Indeed, producing monolithic parts using additive manufacturing minimizes the number of parts that need to be assembled to obtain the final device. In some cases, this number is as low as one, requiring no assembly at all.
[0057] In one embodiment, the waveguide array 1 operates as a combiner / splitter and / or as a beamforming array. Reference numbers for figures: Waveguide array, First waveguide, Second waveguide, Waveguide pair, Groove, Common wall, Antenna array
Claims
Claims 1. Waveguide network (1) obtained by additive manufacturing comprising waveguides arranged two by two so as to form at least one pair of waveguides (12), each pair of waveguides comprising: a first waveguide (10) of trapezoidal section, and a second waveguide (11) of trapezoidal section; characterized in that the first waveguide and the second waveguide have a common wall (100).
2. Network according to claim 1, in which the common wall corresponds to a small base of the trapezoidal sections of the first and second waveguides.
3. Network according to claim 1, in which the common wall corresponds to a large base of the trapezoidal sections of the first and second waveguides.
4. Network according to claim 1, in which the common wall corresponds to a side adjacent to the bases of the trapezoidal sections of the first and second waveguides.
5. Network according to one of the preceding claims, the first waveguide being intended to propagate a first polarization (P1) and the second waveguide being intended to propagate a second polarization (P2).
6. Network according to one of the preceding claims, the number of waveguides being greater than or equal to four so as to form at least two pairs of waveguides (12), the common wall of the waveguides of a first pair corresponding to the small base of the sections trapezoidal and the common wall of the waveguides of a second pair corresponding to the large base of the trapezoidal sections.
7. Network according to one of the preceding claims, the number of waveguides being greater than or equal to four and the pairs of waveguides being arranged contiguously in a first direction so that two successive pairs in the first direction have at least one waveguide wall in common.
8. Network according to one of the preceding claims, the number of waveguides being greater than or equal to four and the pairs of waveguides being arranged contiguously in a first direction and in a second direction, such that two successive pairs in the first direction have at least one waveguide wall in common and such that two successive pairs in the second direction have at least one waveguide wall in common.
9. Network according to the preceding claim, the at least one waveguide wall in common of the successive pairs in the first direction corresponding to a base of the trapezoidal sections of the waveguides and the at least one waveguide wall in common of the successive pairs in the second direction corresponding to a side adjacent to the bases of the trapezoidal sections of the waveguides.
10. Network according to one of the preceding claims, in which an inner wall of the first waveguide (10) and an inner wall of the second waveguide (11) comprise a groove (14).
11. Network according to one of the preceding claims, in which two internal walls of the first waveguide (10) and two internal walls of the second waveguide (11) comprise a groove (14).
12. Network according to the preceding claim, in which the two internal walls correspond to bases of the trapezoidal section of the first and second waveguides.
13. Network according to one of the preceding claims, in which each trapezoidal section is an isosceles trapezoid or a parallelogram.
14. Waveguide network according to one of the preceding claims adapted to operate as a combiner network.
15. Dual polarization antenna array (2) obtained by additive manufacturing comprising: a waveguide array (1) according to one of the preceding claims, a plurality of radiating elements (20), each radiating element being coupled to the end of exactly one pair (12) of waveguides of the array.
16. Antenna array (2) according to the preceding claim, the waveguide array (1) comprising at least eight waveguides and the pairs of waveguides being arranged contiguously in a first direction and in a second direction, such that two successive pairs in the first direction have at least one waveguide wall in common and such that two successive pairs in the second direction have at least one waveguide wall in common.