Multilayer waveguide with metasurface, arrangement thereof and method of production

Abstract

A multilayer waveguide (1) comprises at least three physical layers (21, 2a, 2b, 2c, ..., 2n, 22) assembled into the multilayer waveguide (1). The layers are a top layer (21), one or more intermediate layers (2a, 2b, ..., 2n) and a bottom layer (22). The multilayer waveguide (1) further comprises a waveguide channel (77), which is an elongated hole (7) in at least one of the intermediate layers (2a, 2b, ..., 2n). At least one layer (21, 2a, 2b, ..., 2n, 22) has a metasurface (3) on a first surface (5a) facing a first adjacent layer, wherein the metasurface (3) surrounds the elongated hole (7) and comprises a thick portion (3a) and a thin portion (3b).

Description

Technical Field

[0001] The present invention generally relates to multilayer waveguide transmission lines having layers including electromagnetic metasurfaces. Background Art

[0002] Waveguides are well known in the art and are common components used to transmit electromagnetic waves from a starting point to a destination. In the most general terms, a waveguide may be a hollow metal tube.

[0003] For waves propagating in open space, energy is lost with distance, reducing the possible transmission distance and the quality of the wave. Therefore, a waveguide is a structure suitable for guiding waves by limiting the direction of their expansion in at least one dimension. The concept is to confine the wave, forcing it to propagate in a specific direction, thereby reducing losses. Under ideal conditions, this would result in a wave that loses no energy at all, however, this is rarely or never the case. According to waveguide transmission lines, there are losses and leakages, and the waves couple to the edges of the waveguide channel, resulting in energy losses. The concept of waveguides has been known for a long time and is used to transmit, for example, signals, sound or light.

[0004] At the same time, the use of wireless communications increases, and there is a market demand for waveguides and antenna arrays based on this technology. The market demand further requires compact and inexpensive waveguides.

[0005] One available solution is substrate integrated waveguide (SIW), which is a compact waveguide based on printed circuit board (PCB) technology that uses via holes to connect the top and bottom layers. A via is a hole that extends between the layers of the waveguide, connecting at least the top and bottom layers. Although cost-effective production methods exist for substrate integrated waveguides, the cost increases with increasing frequency due to the need for high-frequency dielectrics.

[0006] Another available solution is the so-called gap waveguide technology. Gap waveguides are usually made of two parts, one of which has pins that form a barrier that prevents electromagnetic waves from propagating in directions other than the intended waveguide direction, thereby reducing leakage in such structures. Gap waveguides are suitable for some applications, but are limited in size, with the typical height of the pins being the wavelength divided by 2 to 6, i.e. λ / 2 to λ / 6. SUMMARY OF THE INVENTION

[0008] Although the technology for compact waveguides is available, there is a need for compact components, low loss components with good loss and leakage reduction. As an example, SIWs have an inherent insertion loss that is higher than the corresponding loss of, for example, an air-filled hollow waveguide. Therefore, although they provide a cost-effective alternative, other solutions are still needed. Hollow waveguides generally have other disadvantages, for example, the magnetic field can penetrate a short distance into the metal, resulting in leakage, and when the hollow waveguide structure is manufactured in a segmented block, if there is a gap between the two layers, especially if the gap is in the horizontal direction, a large amount of leakage will occur. This is because the electromagnetic waves are severely confined and mean that they can only penetrate a very short distance to enter the metal.

[0009] Dielectric waveguides are another option to reduce leakage, however, the characteristics of the problem are different for such waveguides due to, for example, non-propagating evanescent waves. This is also why such waveguides require high conductivity levels between layers in order to reduce leakage. High conductivity levels significantly increase production costs and require very high precision during manufacturing. In addition, the losses are generally still higher than for air-filled waveguides.

[0010] Gap waveguides have limitations in both the design and size of the pin texture, which makes them a useful solution but not suitable for some applications.

[0011] Another problem associated with the manufacture of waveguides is that the current state of the art in CNC milling and molding generally provides poor tolerances in the production methods compared to other methods such as laser cutting, etching or chemical etching. This makes it difficult and / or expensive to produce the waveguide structure. This problem is more pronounced for certain frequency ranges than for others, for example, both CNC milling and molding are common production methods for waveguides for frequencies below 60 GHz. In the higher E-band and D-band frequency ranges, 71 GHz to 86 GHz and 110 GHz to 170 GHz, CNC milling and molding become very expensive because everything associated with the way the production technology works is very small. Therefore, it is not suitable in some cases, and in some cases it is not even possible to achieve the desired results.

[0012] An object is to provide a new realization of an air-filled waveguide transmission line that is easy to produce.

[0013] Another object is to provide a waveguide that is cost-effective to produce.

[0014] Another object is to provide a waveguide that can be conveniently used in and designed for antenna arrays.

[0015] Another object is to provide a waveguide that can be conveniently used to design waveguide filters and duplexers.

[0016] Another object is to provide a waveguide that can be conveniently used for active electronic circuits, ie power amplifiers (PA), packaging, and integration with passive components such as array antennas.

[0017] Another object is to provide a multilayer waveguide of stacked unconnected layers with low leakage.

[0018] Another object is to provide a multilayer waveguide that does not require galvanic contacts between layers to reduce leakage.

[0019] It is another object of the present invention to provide a multilayer waveguide that does not require connectivity between layers to reduce leakage.

[0020] It is a further object of the invention to provide a multilayer waveguide which is compact compared to prior art solutions.

[0021] Therefore, a waveguide that is compact and overcomes at least some of the disadvantages of the prior art would be beneficial.

[0022] Therefore, the present solution relates to a cost-effective and easy-to-produce multilayer waveguide transmission line having an electromagnetic metasurface arranged in a specific configuration. The solution is a compact air-filled waveguide with thin layers that are not connected and stacked together, and overcomes many disadvantages of prior art solutions. The solution can be advantageously used with metal layers with a typical thickness of λ / 10 or λ / 15 and a depth of a leakage suppression structure lower than λ / 20 or even λ / 30. The multilayer waveguide includes at least three physical layers assembled into a multilayer waveguide. These layers are at least one top layer, one or more intermediate layers and a bottom layer. The multilayer waveguide also includes a waveguide channel, which is an elongated aperture in at least one intermediate layer. At least one layer has a metasurface on a first surface facing a first adjacent layer, and the metasurface surrounds the elongated aperture. The metasurface includes a thick portion and a thin portion.

[0023] In different embodiments, the waveguide channels are arranged in layers with elongated holes of different sizes, in some embodiments all layers have elongated holes of different sizes, and in other embodiments some layers have corresponding holes.

[0024] A metasurface is a textured surface with a sub-wavelength thickness, which in this particular case is typically below λ / 10. The textured surface consists of a thin portion where the texture is created and a thick portion.

[0025] One advantage is that the metastructure in a multilayer arrangement creates a leakage-reducing effect through the small gaps between the layers and the metasurface. This effect comes from the electromagnetic bandgap, but compared to previous multilayer waveguides, the metasurface structure has the advantage of being smaller in size and still cheap to produce.

[0026] According to one embodiment, the first surface has a flat portion surrounding the metasurface. The thick portion has a thickness corresponding to the thickness of the layer at the flat portion, and the thin portion has a thickness less than the thickness at the flat portion.

[0027] According to one embodiment, the second surface of the intermediate layer faces the second adjacent layer, which second adjacent layer has a flat surface except for the elongated holes.

[0028] The metasurface is oriented toward the flat surface, creating small air-filled spaces between the surfaces of the layers, resulting in an electromagnetic bandgap structure.

[0029] According to one embodiment, the layers are stacked separate layers with no elements extending between the layers.

[0030] An advantage of this solution is that small gaps between all or some of the layers are acceptable without increasing leakage.

[0031] According to one embodiment, each thick portion has any one of a circular, oval, triangular, square, pentagonal, rectangular, rectangular, square, hexagonal or rectangular shape.

[0032] One advantage is that the shape of the thick portion can vary between different layers or different waveguides.

[0033] According to one embodiment, the thick portions are arranged in rows parallel to the elongated holes.

[0034] According to one embodiment, the thick portion is arranged at irregular distances from the elongated hole.

[0035] According to one embodiment, the thick portions are arranged in a random pattern around the elongated holes.

[0036] According to one embodiment, the metasurface surrounds the elongated hole.

[0037] According to one embodiment, a multilayer waveguide includes a first intermediate layer, a second intermediate layer, and a third intermediate layer, each intermediate layer including an elongated hole, and the second intermediate layer further including a central member disposed within the elongated hole.

[0038] In different embodiments, all or some layers have a metasurface. In one embodiment, only the middle layer has a metasurface, in another embodiment, at least one of the top and bottom layers has a metasurface. In one embodiment, the metasurface is arranged to face the flat surface of the adjacent layer, i.e., in such an embodiment, the two metasurfaces do not face each other.

[0039] According to one embodiment, a multilayer waveguide includes a first intermediate layer, a second intermediate layer, and a third intermediate layer, wherein the second intermediate layer is a non-textured layer for an integrated electronic chipset.

[0040] One advantage is that non-textured layers, ie layers without a metasurface, can be used to integrate electronic chipsets.

[0041] According to one embodiment, the difference in thickness between the thick and thin portions of the metasurface is less than the wavelength divided by ten.

[0042] According to one embodiment, the difference in thickness between the thick and thin portions of the metasurface is less than the wavelength divided by 20.

[0043] According to one embodiment, the difference in thickness between the thick and thin portions of the metasurface is less than the wavelength divided by 30.

[0044] One advantage of this solution is that the metasurface allows for smaller waveguide dimensions without increasing leakage compared to other available alternatives. Another advantage of combining a multilayer structure with a metasurface is that leakage between layers is significantly reduced. While larger metasurfaces are a possibility, a clear advantage is that smaller metasurfaces are easier to produce than alternatives for the corresponding frequencies.

[0045] According to one aspect, a method for producing a multilayer waveguide as described herein is disclosed.

[0046] According to an embodiment, metasurfaces of different layers in a multilayer waveguide have an asymmetric configuration.

[0047] One advantage of the present solution is that the metasurface of each layer in a multilayer waveguide having a metasurface does not have to be identical. For example, the metasurface can be arranged to have thick and thin portions aligned with each other between layers, or in an asymmetric configuration where the thin and thick portions are not aligned.

[0048] According to an embodiment, the thin portions and the thick portions are periodically arranged along the periphery outside the elongated holes of each layer.

[0049] According to one embodiment, the metasurface on each layer is different.

[0050] According to an embodiment, the central member of the elongated hole is connected to the rest of the layer by a connection tab spanning the hole, wherein the connection tab is an integral part of the layer.

[0051] According to an embodiment, the distance between the layers of the multilayer waveguide is between 0 and 20 microns.

[0052] According to an embodiment, the distance between the layers of the multilayer waveguide is between 0 and 50 micrometers.

[0053] According to an embodiment, the multilayer waveguide is a transmission line implemented as any one of an antenna, an antenna array, and a filter.

[0054] An advantage of the present solution is that the multilayer waveguide can be realized as, for example, a slotted waveguide antenna.

[0055] Another advantage of the present solution is that multilayer waveguides can be implemented for chipset packaging, such as MMIC (Monolithic Microwave Integrated Circuit) packaging.

[0056] According to an embodiment, the waveguide is made of one single material.

[0057] According to an embodiment, the multilayer waveguide is made of layers of a single material coated with metal.

[0058] According to an embodiment, the multilayer waveguide is assembled with a non-conductive adhesive.

[0059] According to an embodiment, the layers are directly stacked.

[0060] According to an embodiment, the layers are stacked thin layers that are not connected.

[0061] One advantage is that multilayer waveguides do not require any galvanic, electrical or physical connections between layers. That is, there can be small gaps between layers. The gaps can be, for example, uncontrolled air gaps from the production of the layers. The gaps can also be micrometer-scale, or even atomic-scale.

[0062] According to an embodiment, the layers are stacked thin metal layers that are not connected.

[0063] According to an embodiment, the layers of the multilayer waveguide are held together using any one of a conductive glue, an isolation glue, and two screws.

[0064] One advantage of the present solution is that any form of bonding or attachment means can be used to hold the layers together. The reason for this is that no conductivity is required between the layers to suppress leakage. However, it should be noted that the conductivity does not negatively affect the performance. That is, the multilayer waveguide according to the solution described herein works well regardless of the conductive properties between the layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0067] Figure 1 One embodiment of a multilayer waveguide having layers including a metasurface is shown, with the top layer presented in an exploded view.

[0068] Figure 2 One embodiment of an equidistant cross section of an intermediate layer is shown.

[0069] Figure 3 An exploded view of one embodiment of a multilayer waveguide having a layer including a metasurface is shown.

[0070] Figure 4 Shown as Figure 3 Cross section of the embodiment shown.

[0071] Figure 5 A cross-section of a portion of the intermediate layer is shown, showing the thin and thick portions of the metasurface in detail.

[0072] Figure 6 A cross section is shown showing one embodiment of a metasurface in multiple layers, where the metasurface is produced using chemical etching as a manufacturing method.

[0073] Figure 7 An embodiment is shown showing a coaxial multilayer waveguide with a metasurface in multiple layers.

[0074] Figure 8 A cross section of one embodiment of a coaxial multilayer waveguide having a planar layer between layers having a metasurface is shown.

[0075] Fig. 9 A cross section of one embodiment of a rectangular multilayer waveguide with a metasurface in the bottom layer is shown.

[0076] Fig.10 An embodiment is shown in which the metasurface portion has a circular shape.

[0077] Fig.11 An embodiment is shown in which thick portions and / or thin portions are arranged unevenly in the metasurface.

[0078] Fig.12 An embodiment is shown in which multiple waveguides are arranged into a slotted waveguide antenna in a unit.

[0079] Fig.13 It shows that according to Fig.12 Bottom view of the top layer of the illustrated embodiment.

[0080] Fig.14 One embodiment of a multilayer waveguide arranged as a slotted waveguide antenna is shown.

[0081] Fig.15 An embodiment of a multilayer waveguide arranged as a slotted waveguide antenna is shown, wherein corrugations for reducing unwanted signal propagation are arranged in the extension direction of the waveguide channel.

[0082] Description of Embodiments

[0083] In the following, a detailed description of different embodiments of the invention is disclosed with reference to the accompanying drawings. All examples herein should be considered as part of the general description and can therefore be combined in any way in general terms. Individual features of the various embodiments and aspects can be combined or exchanged, unless such combination or exchange is clearly inconsistent with the overall function of the multilayer waveguide, its arrangement or production method.

[0084] Briefly described, the solution involves a compact multilayer waveguide without any electrical and galvanic contact between the layers. The multilayer waveguide has a metasurface in the layers arranged as a leakage suppression structure for reducing energy leakage between the layers of the waveguide. The metasurface includes multiple thick and thin sections surrounding the waveguide channel.

[0085] Figure 1 An embodiment of a multilayer waveguide 1 having a plurality of layers 21, 2a, 2b, 2c, 22 of the multilayer waveguide is shown. The intermediate layers 2a, 2b, 2c, 2d, 2e each have an elongated hole 7 which, alone or together with the elongated holes of other layers, forms a waveguide channel 77. The elongated holes 7 are in some or all of the intermediate layers surrounded by the metasurface.

[0086] Figure 2 A cross section of a portion of the intermediate layer 2b is shown. This layer comprises elongated holes 7, in Figure 2 In the illustration of FIG. 7 , only a portion of the elongated hole 7 is visible. The elongated hole 7 is surrounded by a metasurface 3 comprising a thick portion 3a and a thin portion 3b. The thick portion 3a and the thin portion 3b together form a metasurface, wherein the metasurface suppresses leakage in a manner that helps guide the waves and keeps the waves within a waveguide channel 77 of which the elongated hole 7 is a part.

[0087] Figure 2 Also shown is a flat portion 4 surrounding the metasurface 3. In one embodiment, the flat portion 4 has the same thickness as the thick portion 3a. Figure 2 In the embodiment shown, the thick portions 3a are arranged in straight rows 6a, 6b, 6c. In one embodiment, the number of straight rows 6a, 6b, 6c may be one, two, three or more at any or all sides of the elongated hole 7.

[0088] Figure 3 An embodiment of a multilayer waveguide 1 is shown in which the layers are spaced apart. This exploded view shows an important feature of the multilayer waveguide 1, namely that no galvanic, electrical or physical connection is required between the layers. That is, there can be a small gap between the layers. The gap can be, for example, an uncontrolled air gap resulting from the production of the layers. The gap can also be micrometer-sized, or even atomic-sized. However, it should be noted that as Figure 3 The sizes of the gaps shown are for illustration only, and the gaps between layers can typically be anywhere between 0 and 15 microns.

[0089] Figure 4 A cross section of an embodiment of a multilayer waveguide 1 is shown, wherein an inlet opening 30 and an outlet opening 31 are visible. These openings 30, 31 are the openings wherein waves enter and leave the waveguide channel 77. Figure 4 Also shown are the first surface 5a and the second surface 5b identified for one intermediate layer 2b. It should be noted that each layer comprises a first surface 5a and a second surface 5b. The inlet opening 30 and the outlet opening 31 are not necessarily arranged in the bottom layer 22. In another embodiment, the inlet opening 30 and the outlet opening 31 are arranged in the top layer 21 instead. In yet another embodiment, the inlet opening 30 and the outlet opening 31 are arranged in different layers, for example, the inlet opening 30 can be arranged in the top layer 21, and the outlet opening 31 can be arranged in the bottom layer 22, or vice versa.

[0090] Figure 5 A portion of an intermediate layer 2a, 2b, ..., 2n or a portion of a top layer 21 or a portion of a bottom layer 22 having a metasurface 3 is shown. Figure 5 The thickness difference between the thick and thin parts 3a, 3b and the flat parts 4 is shown. The difference may for example be between 50-70%, 50-60%, 55-65% or 60-70% of the total thickness of the layer, however the thickness difference may also vary outside said ranges.

[0091] Figure 6 An embodiment of a metasurface 3 is shown, wherein the metasurface 3 is produced by metal chemical etching, which produces a characteristic shape of the edge in the metasurface, and the shape of the edge in the metasurface becomes rounded. It should be noted that other production methods such as CNC, laser cutting, etc. are also possible.

[0092] Figure 7 A coaxial multilayer waveguide 1 is shown in which a waveguide channel 77 comprises a central member 8 arranged within an elongated hole 7 of one of the intermediate layers 2a, 2b, 2c, ..., 2n. The central member 8 is attached to the rest of the layer at one or more locations which connect the central member to the layer and hold it in place.

[0093] Figure 8 An embodiment of a coaxial multilayer waveguide 1 is shown, in which the top layer 21 and the bottom layer 22 have a metasurface 3. It should be noted that in some embodiments, the top layer 21 and the bottom layer 22 have a metasurface 3, while in some embodiments, they do not have a metasurface 3. Furthermore, in some embodiments, such as Figure 8 As shown, one or more intermediate layers do not have a metasurface 3.

[0094] Fig. 9 Another embodiment of a multilayer waveguide 1 is shown, wherein the top layer 21 does not have any metasurface, but the middle layers 2a, 2b, 2c and the bottom layer 22 have metasurfaces.

[0095] Fig.10 An embodiment of the intermediate layers 2a, 2b, 2c, ..., 2n is shown, wherein the thick portion 3a has a circular shape. It should be noted that the shape is not important for functionality, and the metasurface 3 may have many different shapes of thick portions 3a in the same and different metasurfaces 3.

[0096] Fig.11 Another embodiment is shown, in which the thick portions 3a of the metasurface 3 are randomly placed around the elongated holes 7. Fig.11 is a representation of how the thick portion 3a may be arranged, but it should be noted that only different possible embodiments are described herein and other arrangements of the thick portion 3a are possible within the scope of the claims. The small gap between the layer and the metasurface provides an electromagnetic bandgap (EBG) structure.

[0097] Fig.12 An exploded isometric view of a multi-layer slotted waveguide antenna 40 is shown as one implementation of the waveguide 1 described herein. Fig.12 The illustrated embodiment shows a top layer 21, an intermediate layer 2a and a bottom layer 22. The top layer 21 comprises an antenna slot 41 and a groove 42 arranged at one end of the waveguide 1. The intermediate layer 2a comprises an elongated hole 7 providing wiring in each waveguide 1. The bottom layer 22 and the top layer 21 comprise a metasurface 3 arranged to surround the elongated hole 7 of the intermediate layer 2a.

[0098] like Fig.12 The elongated holes 7 shown include a support structure for mechanical support of the reinforcement layer. The support structure is arranged in the elongated holes 7, which provides an embodiment in which a plurality of elongated holes 7 are arranged instead of a single hole extending the entire length. In one embodiment, this is only used for structural support.

[0099] Fig.13 Shown as Fig.122a. As shown, in one embodiment, the top layer 21 includes a metasurface 3 arranged to surround the elongated holes 7 of the middle layer 2a. As will be appreciated, Fig.12 and Fig.13 The illustrated embodiment is merely an example of how the solutions described herein may be implemented as a slotted waveguide antenna 40 . Fig.12 and Fig.13 It is also shown how the routing of the waveguide 1 may differ depending on the implementation. For example, in one embodiment the routing may be straight, while in another embodiment the routing may include one or more turns.

[0100] Fig.14 One embodiment of a multilayer waveguide 1 implemented as a slotted waveguide antenna 40 is shown. Fig.15 A slightly more complex multilayer waveguide 1 implemented as a slotted waveguide antenna 40 is shown, in which the grooves 42 are arranged to reduce ripples in the transmission pattern. The grooves 42 reduce surface currents in the top layer and thus enhance the propagation pattern. Fig.14 As shown, the groove 42 extends through the top layer 21 and the middle layer 2a. In another embodiment, where the multilayer waveguide implemented as a slotted waveguide antenna 40 includes additional middle layers 2b, 2c, ..., 2n, the groove 42 extends through the top layer 21 and the middle layers 2a, 2b, 2c, ..., 2n. In yet another embodiment, the groove 42 extends through at least the top layer 21 and at least some of the middle layers 2a, 2b, 2c, ..., 2n.

Claims

1. A multilayer waveguide (1), comprising at least three physical layers (21, 2a, 2b, 2c, ..., 2n, 22) assembled into the multilayer waveguide (1), in, The layers are a top layer (21), one or more intermediate layers (2a, 2b, ..., 2n) and a bottom layer (22), the multilayer waveguide (1) comprises a waveguide channel (77), the waveguide channel (77) being an elongated hole (7) in at least one of the intermediate layers (2a, 2b, ..., 2n), the multilayer waveguide (1) being characterized in that at least one layer (21, 2a, 2b, ..., 2n, 22) has a metasurface (3) on a first surface (5a) facing a first adjacent layer, wherein the metasurface (3) surrounds the elongated hole (7), and The metasurface (3) is a textured surface having a sub-wavelength thickness less than the wavelength divided by 10, the textured surface being produced by a thick portion (3a) and a thin portion (3b), wherein the top layer (21) has a metasurface on a surface facing a first side of the one or more intermediate layers (2a, 2b, ..., 2n), and the bottom layer has a metasurface (3) on a surface facing a second side of the one or more intermediate layers, and wherein the one or more intermediate layers have a flat surface on the first side or the second side except for the elongated hole.

2. The multilayer waveguide (1) according to claim 1, in, The first surface (5a) has a flat portion (4) surrounding the metasurface (3), and wherein the thick portion (3a) has a thickness corresponding to a layer thickness (L1) at the flat portion (4), and the thin portion (3b) has a thickness (L2) smaller than the thickness at the flat portion (4).

3. The multilayer waveguide (1) according to claim 1, in, The second surface (5b) of the layer (21, 2a, 2b, ..., 2n, 22) facing the second adjacent layer is a flat surface except for the elongated holes (7).

4. The multilayer waveguide (1) according to claim 2, in, The second surface (5b) of the layer (21, 2a, 2b, ..., 2n, 22) facing the second adjacent layer is a flat surface except for the elongated holes (7).

5. The multilayer waveguide (1) according to any one of claims 1 to 4, wherein the layers (21, 2a, 2b, 2c, ..., 2n, 22) are stacked separate layers with no elements extending between the layers (21, 2a, 2b, 2c, ..., 2n, 22).

6. The multilayer waveguide (1) according to any one of claims 1 to 4, in, Each thick portion (3a) has any one of a circular, elliptical, triangular, pentagonal, rectangular, or hexagonal shape.

7. The multilayer waveguide (1) according to any one of claims 1 to 4, in, Each thick portion (3a) has a square shape.

8. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The thick portions (3a) are arranged in rows (6a, 6b, 6c, ..., 6n) parallel to the elongated holes (7).

9. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The thick portion (3a) is arranged at an irregular distance from the elongated hole (7).

10. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The super surface (3) surrounds the elongated hole (7).

11. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The multilayer waveguide comprises a first intermediate layer (2a), a second intermediate layer (2b) and a third intermediate layer (2c), each intermediate layer comprising an elongated hole (7), and wherein the second intermediate layer (2b) further comprises a central member (8) arranged within the elongated hole (7).

12. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The multilayer waveguide comprises a first intermediate layer (2a), a second intermediate layer (2b) and a third intermediate layer (2c), wherein the second intermediate layer (2b) is a non-textured layer for an integrated electronic chipset.

13. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The thickness difference (L3) between the thick portion (3a) and the thin portion (3b) of the metasurface (3) is less than the wavelength divided by 20.

14. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The thickness difference (L3) between the thick portion (3a) and the thin portion (3b) of the metasurface (3) is less than the wavelength divided by 25.

15. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The multilayer waveguide (1) is implemented as a slotted waveguide antenna (40).

16. The multilayer waveguide (1) according to any one of claims 1 to 4, in, The top layer (21) comprises an antenna slot (41).

17. A method for producing a multilayer waveguide (1) according to any one of claims 1 to 16.

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