A multilayer waveguide assembly and a method of manufacturing the same

Abstract

The present disclosure relates to a multi-layer waveguide device and a method for manufacturing a waveguide device. The waveguide device comprises a first layer (1) and a second layer (2), wherein the first layer (1) and the second layer (2) comprise at least one through opening (11a, 11b, 21a, 21b), and wherein the at least two layers (1, 2) are arranged together such that the through openings (11a, 21a) form respective passages (9a) extending from an outer surface (1a) of the first layer (1) to an outer surface (2a) of the second layer (2). The at least two layers (1, 2) form, when arranged together, a waveguide for an operating wavelength, and the device further comprises an integral holding element (8') extending through the at least one passage (9a).

Description

[0001] Technical Field of the Invention The present invention relates to a method for manufacturing a multilayer waveguide and the multilayer waveguide formed by said method. Background of the Invention Waveguide devices, such as antennas for transmitting and receiving electromagnetic radiation or filters for filtering electromagnetic signals, are crucial in modern society. For example, antennas are essential for wireless communication and are also used in radar applications to transmit and detect radar signals. Therefore, multiple antennas are integrated into most modern cars (and other vehicles) for wireless communication purposes and radar detection of the surrounding environment.

[0003] In many applications, particularly automotive applications, it is important that antennas are cost-effective to manufacture, small and thin for easy integration, and provide excellent radiation performance at high frequencies. These requirements have led to the widespread adoption of waveguide structures that utilize multiple layers forming gapped waveguides.

[0004] However, the problem with multilayer waveguide structures is that the manufacturing process can be expensive and time-consuming, as multiple layers must be riveted or glued together in numerous locations.

[0005] When using rivets, multiple through holes must be formed through each layer, and the rivets must be installed one by one. In some cases, riveting risks damaging fragile layers when the tail deforms. In the applicant's international application WO21151538, a multilayer waveguide device with rivets integrated into a single layer is proposed. According to this embodiment, rivets can be integrated with one of the layers, whereby they can deform or melt to hold all layers together. However, a disadvantage is that the integrated rivets are fragile and must be formed from the same material as the layer to which the rivet is integrated; however, it may be desirable to use different materials. Additionally, the rivets and the necessary surrounding geometry are space-consuming and cannot be placed in all desired locations.

[0006] The disadvantage of using adhesives is that they typically do not provide the same secure mounting as rivets. Additionally, applying adhesive between layers increases the spacing between them, which can be detrimental to waveguide performance in some implementations.

[0007] General disclosure of the invention The purpose of this invention is to overcome at least some of the disadvantages of existing solutions and to provide a method for manufacturing a multilayer waveguide device that is accurate and reliable, thereby obtaining a multilayer waveguide device that is securely assembled.

[0008] According to a first aspect of the invention, a multilayer waveguide assembly is provided, comprising at least two layers, a first layer and a second layer. Each of the first and second layers includes at least one through-hole, wherein the at least two layers are arranged together such that the through-hole in each layer forms a corresponding channel extending from the outer surface of the first layer to the outer surface of the second layer. When arranged together, the at least two layers form a channel for an operating wavelength. The device also includes a waveguide and an integral retaining element extending through at least one channel, wherein the integral retaining element has been formed directly in the channel by a molding process, wherein at least one channel acts as part of a mold.

[0009] The integral retaining element, formed through a molding process using a channel as part of the mold, is a novel type of retaining element used to hold the fragile layers of a multilayer waveguide together. The integral retaining element is formed as a single piece (i.e., as a monolithic component), which enhances its strength. Furthermore, because the integral retaining element is formed, for example, by injection molding directly inside the channel, it typically fills the entire channel, enabling more reliable layer retention. This also allows the channel itself to be designed with bends or kinks, which is impossible with other types of fastening devices.

[0010] In some implementations, each opening that forms a channel together when the layers are held together will act as a mold for the integrally formed retaining element.

[0011] In some embodiments, at least one channel is curved or bent, and the integral retaining element disposed within the channel is also curved or bent. Therefore, the channel can be shaped to prevent rigid, straight rivets from passing through it.

[0012] In some implementations, the integral retaining element completely fills the interior of at least one channel.

[0013] For example, it can be compared to conventional fusible rivets used to hold the layers of a multilayer waveguide together. Fusible rivets can be integral and manufactured in an injection molding process using an external mold. However, fusible rivets must include a tail with a diameter smaller than the channel diameter. In use, the fusible rivet is inserted into the channel formed by the layers, with the tail protruding beyond the channel, whereby the tail can be melted to form a head for holding the layers together. However, with conventional fusible rivets, pressure is primarily applied by the rivet head, which exerts a clamping force on the layers, risking damage or deformation. Furthermore, even after forming the head by melting the end portion of the tail, the tail will still be smaller than the channel, introducing the risk of the layers slipping relative to each other.

[0014] By utilizing the integral retaining element according to this disclosure (which is formed using a channel that is part of the mold), the pressure from the head and from inside the channel on each layer will be more evenly distributed, which achieves more reliable fastening and reduces the risk of damaging the layers or the layers sliding relative to each other.

[0015] While injection molding of moldable material into channels is one example of how integral retaining elements can be formed, other molding techniques such as compression molding or resin transfer molding (e.g., epoxy resin) can also be used to form integral retaining elements. For example, in compression molding, a (e.g., solid) molding material is placed in a channel, where pressure (and optionally heat) is applied to form an integral retaining element that fills the channel.

[0016] In some embodiments, each through opening includes a corresponding throat segment with a minimum opening size, and wherein the integral retaining element includes a first head portion at a first layer and a second head portion at a second layer, whereby the first head portion and the second head portion are connected via a neck portion. The neck portion extends through the throat segment, and wherein the dimensions of the first head portion and the second head portion are larger than the minimum opening size in the corresponding throat segment.

[0017] In other words, by forming a monolithically shaped retaining element with a relatively wide head portion and a relatively narrow neck portion, the layers will be held together in a highly reliable manner, and the risk of layer loosening is very low. Since the monolithic retaining element can be formed by direct injection into the channel or by compression molding, the overall profile of the throat segment and through-hole can be realized to have arbitrary shapes. Especially when using injection molding, the liquid moldable material can creep around the corners and even fill the most complex geometries (unlike fastening with rivets, screws, etc.).

[0018] In some embodiments, the first layer and the second layer each include at least two through openings to form at least two channels when the layers are arranged together, and the integral retaining element includes a first structure extending between the at least two channels on the outer surface of the first layer, wherein the integral retaining element extends through the at least two channels.

[0019] With multiple through openings in each layer, multiple channels are formed when the layers are arranged together, and the integral retaining element can hold the layers together at multiple locations, allowing the clamping pressure on the layers to be distributed more evenly. This ensures, for example, that there is contact between the layers at more locations and reduces the risk of layer deformation caused by unevenly distributed clamping pressure. The first structure of the integral retaining element connects the various parts of the integral retaining element that pass through the channels, thereby further enhancing the structural stability of the multilayer waveguide device.

[0020] When these layers are arranged together, the through openings in the first layer are arranged to match the through openings in the second layer, i.e., to connect them. Similarly, if more than two layers are provided, when these layers are arranged together, the through openings in each layer match the through openings in the other layers to form optional curved or bent channels.

[0021] In some embodiments, the first and second layers each include at least two through openings to form at least two channels when the layers are arranged together. The integral retaining element includes a second structure extending between at least two channels on the outer surface of the second layer.

[0022] Similar to the first structure extending above the first outer surface, the second structure extends above the second outer surface to connect the portion of the integral retaining element that extends through at least two channels. Both the first and second structures are optional, and embodiments with only the first structure, only the second structure, or both are contemplated. The first and / or second structure is formed in which a portion of the outer surface of the first and / or second layer serves as part of the mold.

[0023] When both the first structure and the second structure are provided, the first structure and the second structure can be integrally attached through at least two channels. That is, the integral retaining element can be formed as a single component that covers a portion of the first outer surface, covers a portion of the second outer surface, and extends through at least two channels.

[0024] In some implementations, the second structure forms a support configured to be mounted against the PCB to hold the second layer of the multilayer waveguide assembly at a distance from the PCB.

[0025] Therefore, the second structure can also function as a mounting device for mounting towards the PCB. Thus, the retaining element, formed integrally, can also include features to facilitate mounting against the PCB. For example, the support can be a pin or a protruding section that can abut against the PCB while allowing sufficient space for placing electronic components of the PCB between the PCB and the second structure.

[0026] According to a second aspect of the invention, a multilayer waveguide system is provided, including a PCB and a multilayer waveguide assembly according to a first aspect, wherein the multilayer waveguide assembly is mounted on the PCB using a support that contacts the PCB.

[0027] Optionally, the second structure may include at least one opening exposing the outer surface of the second layer, thereby allowing electronic components of the PCB to directly contact the second layer in thermal contact. Since the layers may be made of metal (or at least coated with metal), they can serve as heat sinks for components on the PCB.

[0028] In some embodiments, at least one structure forms a substantially flat layer. Depending on the material used for the integral retaining element, when the multilayer waveguide is used as an antenna, the substantially flat layer can, for example, act as an absorbing layer to absorb electromagnetic radiation. As another example, the substantially flat layer can be made of a conductive material (such as a conductive plastic material), wherein the substantially flat layer can be corrugated and act as a corrugated layer, which enhances radiation performance when the multilayer waveguide is used as an antenna.

[0029] In some embodiments, a substantially flat layer covers at least 50%, preferably at least 70%, of the outer surface of the first or second layer.

[0030] In other words, a substantially flat layer can cover most of the outer surface of at least one of the first and second layers.

[0031] In some embodiments, the first layer includes one or more antenna apertures, wherein the first structure forms a substantially flat layer, and wherein the substantially flat layer includes at least one opening surrounding one or more antenna apertures.

[0032] To allow one or more antennas to communicate with the environment, the substantially flat layer may include one or more openings around the antennas. The openings may be formed simultaneously with integrally formed holding elements. Alternatively, one or more openings may be formed within the substantially flat layer after it has already been formed.

[0033] In some embodiments, the substantially flat layer or at least a portion thereof overlapping with one or more antenna openings is made of a radiation-transparent material that allows electromagnetic radiation at the operating frequency to pass through.

[0034] In some implementations, the first and second layers each include at least three through openings to form at least three channels when the layers are arranged together, wherein at least one structure is shaped like a web extending between the at least three channels.

[0035] When three or more channels are provided, the first structure can form a mesh (which may also be called a net or grid) extending above the outer surface of the first layer to connect the portions of the integral retaining element that pass through the at least three channels. Compared to a substantially flat solid layer covering most of the outer surface, the mesh still connects the portions of the integral retaining element that extend through the channels, while still exposing a large portion (e.g., most) of the first outer surface. This reduces the material required to form the integral retaining element and / or enhances heat dissipation of the layer if the integral retaining element is formed of an insulating material.

[0036] In some embodiments, the multilayer waveguide further includes a third layer, wherein the third layer includes at least one through-opening, and wherein the first layer also includes an additional through-opening. The third layer is disposed outside the first layer and opposite the second layer, such that the through-opening of the third layer forms an additional channel extending from the outer surface of the third layer to the inner surface of the first layer. The multilayer waveguide also includes an additional integral retaining element extending through the additional channel, wherein the additional integral retaining element has been directly formed in the second channel by injection molding or compression molding, wherein the additional channel and the second layer serve as part of the mold.

[0037] In other words, when using three or more layers, it is not necessary for each monolithic retaining element to pass through all the layers. In addition to using a monolithic retaining element that secures the first layer to the second, it is still possible to achieve a multilayer waveguide assembly in which all layers are directly or indirectly attached to each other by using an additional monolithic retaining element that extends through the third layer to the first layer (and secures the third layer to the first layer). The advantage of this arrangement is that it provides more space for wiring between layers when using many layers, because the same channel does not need to pass through all (at least three) layers.

[0038] In some embodiments, at least one intermediate layer is disposed between the first layer and the second layer, wherein the at least one intermediate layer includes a through opening that together with the through openings in the first layer and the second layer forms a channel.

[0039] Typically, any number of layers can be used, and it is envisioned that one or more, two or more, three or more, or even four or more intermediate layers can be added between the first and second layers to form a multilayer waveguide with a total of at least three, at least four, at least five, or even at least six layers.

[0040] In some implementations, the first and second layers each include at least two through openings to form at least two channels when the layers are arranged together, and the multilayer waveguide assembly includes at least two separate monolithic retaining elements, each monolithic retaining element extending through the respective channel.

[0041] Therefore, as an alternative to or supplement to one or more integral retaining elements extending through multiple channels, multiple individual integral retaining elements can be provided. That is, it is envisioned that the integral retaining element can be a single-channel integral retaining element (which extends through only one channel) or a multi-channel integral retaining element (which extends through at least two channels and includes a structure on a first or second outer surface that extends between at least two channels). The advantage of multiple single-channel integral retaining elements is that the amount of material used is very small and / or very little of the outer surface will be covered by the integral retaining element.

[0042] In some implementations, the space density of channels filled with the same or different integral retaining elements is less than that per 6 channels, preferably less than each Three channels, preferably less than each Two channels, and preferably less than each One channel.

[0043] Multiple integrally formed holding elements are effective in reliably holding layers together, allowing channels to be arranged at a relatively low density relative to wavelength. This ensures ample space between layers for wiring without being obstructed by channels.

[0044] In some embodiments, at least one through opening has an opening size that increases in the direction toward the corresponding outer surface.

[0045] Preferably, this applies to at least one through-hole in the outermost layer (i.e., at least the first and second layers if one or more intermediate layers are arranged between the first and second layers, and / or at least the first and third layers if a third layer exists and is adjacent to the second layer and opposite the first layer). With this type of through-hole, the monolithic retaining element does not need to protrude outwards beyond the outer surface to secure these layers. In practice, the monolithic retaining element can terminate flush with the outer surface, or even at a distance inside the through-hole. Therefore, it is envisioned that the retaining element does not increase the total thickness of the stack of layers forming the multilayer waveguide.

[0046] In some embodiments, at least one of the layers includes a metasurface (4) disposed on a surface facing another layer, wherein the metasurface defines the waveguide and prohibits the operation of wavelengths. The electromagnetic radiation propagates between the layers in directions other than along the waveguide.

[0047] Metasurfaces are configured to contain electromagnetic signals in order to confine them between layers and along a waveguide. In some embodiments, the metasurface is a textured surface comprising multiple thick segments and multiple thin segments. Specifically, the height difference between the thick and thin segments can be very small, for example, less than [missing information]. Divide by 5, or less than Divide by 6, or less than Divide by 8, or even less Divide by 10.

[0048] In some embodiments, the integral retaining element is made of a plastic material, such as polypropylene, polybutylene terephthalate, polycarbonate, conductive plastic material, mixtures thereof, or blends thereof.

[0049] Other suitable materials may also be used. The integral retaining element can be implemented using conductive and / or thermally conductive or insulating materials. For example, the integral retaining element can be made of a plastic material with metallic additives that make it conductive and / or thermally conductive.

[0050] According to a third aspect of the invention, a method for manufacturing a multilayer waveguide assembly is provided. The method includes providing at least two layers comprising a first layer and a second layer, wherein each of the first and second layers includes at least one through-hole. The method further includes holding the at least two layers together such that the through-hole forms a corresponding channel extending from a first aperture in the outer surface of the first layer to a second aperture in the outer surface of the second layer, wherein the at least two layers, when arranged together, form a channel for an operating wavelength. The method also includes forming an integral retaining element extending through at least one channel, wherein the integral retaining element has been directly formed in the channel by a molding process, wherein the at least one channel acts as part of the mold.

[0051] For injection molding processes, forming an integral retaining element may include positioning a first nozzle in communication with a first aperture of at least one channel. The method also includes injecting a fluid moldable material through the first nozzle, such that the fluid moldable material fills the channel, and curing or solidifying the moldable material. For example, the moldable material may solidify by cooling to change it from a liquid phase to a solid phase, or the moldable material may be cured by heat or light (e.g., UV light).

[0052] In other words, the layers of a multilayer waveguide device can be fixed together by directly injecting a liquid moldable material into the channel. The steps of curing and solidifying the moldable material can involve actively or passively cooling the layers to allow the moldable material to solidify.

[0053] The invention according to the third aspect has the same or equivalent benefits as the invention according to the first or second aspect. Any function described with respect to the method can have corresponding features in a multilayer waveguide, and vice versa. Brief description of the attached diagram Various aspects of the invention will be described in more detail with reference to the accompanying drawings, which illustrate currently preferred embodiments.

[0055] Figures 1a-1d A cross-section of a multilayer waveguide device with two layers is shown according to some embodiments.

[0056] Figure 2 This is a flowchart illustrating a method for manufacturing a multilayer waveguide according to some embodiments.

[0057] Figures 3a-3d A cross-sectional view of a multilayer waveguide device having holding elements of different integral formations according to some embodiments is shown.

[0058] Figures 4a-4b Different views of an assembled multilayer waveguide assembly according to some embodiments are shown. The multilayer waveguide assembly has an integrally formed retaining element having a first structure covering most of the first layer.

[0059] Figure 5 An example of a mesh structure of retaining elements integrally formed according to some embodiments is shown.

[0060] Figure 6a and Figure 6b An enlarged cross-sectional view of the retaining element integrally formed according to some embodiments is shown.

[0061] Figures 7a-7c A cross-sectional view of a three-layer multilayer waveguide device according to some embodiments is shown.

[0062] Figures 8a-8b A cross-sectional view of a three-layer multilayer waveguide device held together by integrally formed retaining elements of different types, according to some embodiments, is shown. These integrally formed retaining elements do not extend completely through more than two layers.

[0063] Figure 9 This is a cross-sectional view of a multilayer device with five layers according to some embodiments.

[0064] Detailed description of the present preferred embodiments Figure 1a A cross-sectional side view of two layers 1 and 2 is depicted, which can be held together to form a multilayer waveguide 10 for guiding electromagnetic signals. The multilayer waveguide 10 is configured to operate with a wavelength... The associated operating frequency. The multilayer waveguides presented in this paper are particularly suitable for high frequencies above 10 GHz, above 50 GHz, or even above 60 GHz. However, the same general structure of the multilayer waveguide 10 can also be used for lower frequencies.

[0065] Figure 1a The multilayer waveguide 10 shown includes two layers 1, 2. However, as described below, this is merely an exemplary embodiment, and this disclosure generally covers many types of multilayer waveguides 10 having two, three, four or more layers 1, 2.

[0066] Each layer 1, 2 may be made of metal, such as copper, aluminum, brass, or alloys thereof. Alternatively, one or more layers 1, 2 may be made of non-metallic materials (such as plastic materials) and coated with metal on at least one side or completely covered by metal. It is contemplated that different types of layers 1, 2 may be combined, for example, at least one layer 1 made of metal may be combined with at least one layer 2 made of non-metallic materials and coated with metal.

[0067] Figure 1a The second layer 2 comprises two main surfaces 2a, 2b opposite to each other. The second layer 2 also includes a secondary edge surface defining the thickness of the second layer 2. Similarly, the first layer 1 also comprises two main surfaces 1a, 1b and a secondary edge surface. Typically, each layer 1, 2 used in the multilayer waveguide 10 described herein will be characterized by two corresponding main surfaces 1a, 1b, 2a, 2b and a secondary edge surface, wherein waveguide structures or openings (for example, forming an antenna) are arranged on one or more of the main surfaces 1a, 1b, 2a, 2b, or, if openings are provided, extend between the two main surfaces 1a, 1b, 2a, 2b.

[0068] when Figure 1a When the two layers 1 and 2 are held together, such as Figure 1b As shown, each layer 1, 2 will exhibit corresponding internal main surfaces 1b, 2b (facing the other layer), and each layer will exhibit corresponding external main surfaces 1a, 1b (facing away from the other layer). Typically, the external main surfaces 1a, 1b are referred to as facing outward because they face away from the internal structure of the multilayer waveguide 10. If more than two layers are used to form the stack of layers constituting the multilayer waveguide 10, there will typically still be two external surfaces 1a, 2a, where at least one layer (arranged between two other layers) is characterized by having only an internal surface.

[0069] At least one of layers 1 and 2 includes a structure facing the other layer 1 or 2, which forms a waveguide for guiding electromagnetic radiation when layers 1 and 2 are held together. Figure 1aIn the illustrated embodiment, the second layer 2 includes a recess with a metasurface 4 comprising a thick segment 41 and a thin segment 42. The thick segment 41 and thin segment 42 of the metasurface 4 are configured to prevent electromagnetic signals from propagating between layers in directions other than along paths formed in the metasurface 4. Paths are defined by regions without the metasurface 4, which define waveguides 33. When electromagnetic signals are guided by the waveguide 33, they will travel between the metasurfaces 4, in regions without the metasurface, and between the first layer 1 and the second layer 2. Optionally, ridges 5 may be arranged in regions without the metasurface, wherein the ridges 5 may enhance waveguide characteristics.

[0070] The thick sections 41 and thin sections 42 of the metasurface 4 can be arranged in a regular pattern, for example, a matrix pattern of multiple rows of thick sections 41 and thin sections 42 on either side of the waveguide, or arranged in a random pattern. Preferably, the height difference between the thick sections 41 and thin sections 42 is less than [missing information]. Divide by 5, or less than Divide by 6. Even more preferably, the height difference between the thick section 41 and the thin section 42 is less than... Divide by 8 or Divide by 10. Therefore, since the minimum depth of the recess including metasurface 4 is equal to the height difference between the thick section 41 and the thin section 42, the recess can be manufactured to be very shallow. In turn, this allows the entire second layer 2 to be manufactured to be very thin, with a maximum thickness less than 10. Divide by 4, or even smaller, such as less than Divide by 5 or less Divide by 6.

[0071] For example, at least one or all layers 1, 2 forming a multilayer waveguide can have a smaller than Divided by 4 or less Divide by 5 for the thickness. It is also envisioned that all layers 1 and 2 can have the same thickness, or that layers 1 and 2 can have different thicknesses.

[0072] Each layer 1, 2 also includes at least one through opening 11a, 11b, 21a, 21b extending through layer 1, 2 to form channels 9a, 9b between the two main (outer) surfaces of each layer 1, 2. When layers 1, 2 are held together to form a waveguide, the through openings 11a, 11b, 21a, 21b of layers 1, 2 are arranged to be aligned. That is, each layer 1, 2 includes at least one through opening 11a, 11b, 21a, 21b corresponding to or associated with through openings 11a, 11b, 21a, 21b of adjacent layers, such that when layers 1, 2 are arranged together, the corresponding through opening forms channels 9a, 9b extending through all stacked layers 1, 2.

[0073] like Figure 1b As shown, through openings 21a and 11a form channel 9a, and through openings 21b and 11b form channel 9b, wherein each channel extends between the two outer surfaces of the stacked layers 1 and 2.

[0074] It should also be understood that even if the stack of layers 1 and 2 includes three or more layers 1 and 2, through openings 11a, 11b, 21a, 21b may be arranged in each layer to form channels 9a, 9b extending through all layers 1 and 2 in the stack.

[0075] Figure 1b The channels 9a and 9b depicted are straight and extend perpendicular to the plane in which layers 1 and 2 extend. For example, this means that when layers 1 and 2 are held together, channels 9a and 9b are visible through them. However, this is merely exemplary, and channels 9a and 9b may be arranged at non-perpendicular angles through layers 1 and 2 and / or channels 9a and 9b may include at least one bend or twist, such that channels 9a and 9b are not visible through them.

[0076] The straight channels 9a and 9b disposed in each layer are known in multilayer waveguide devices because they are used to insert screws or rivets to secure layers 1 and 2 together. However, according to an embodiment of the invention, these layers are held together by one or more integrally formed retaining elements that have been directly formed in the channels 9a and 9b by injection molding or compression molding processes, wherein the channels 9a and 9b act as part of the mold.

[0077] Now refer to Figures 1a-1d as well as Figure 2 The flowchart in the diagram describes the process for forming a multilayer waveguide having multiple integrally formed holding elements of this type to hold layers 1 and 2 together.

[0078] In step S1, at least two layers 1 and 2 are provided. As described above, layers 1 and 2 are characterized by a structure such that when layers 1 and 2 are held together, the structure forms a configuration suitable for operation at a specific frequency. The waveguide for electromagnetic signals. Each layer 1, 2 includes at least one through opening 11a, 11b, 21a, 21b. In step S2, at least two layers 1, 2 are held together to form a multilayer waveguide, and the through openings 11a, 11b, 21a, 21b are interconnected to form one or more channels 9a, 9b extending through the stack of layers 1, 2.

[0079] In step S3, nozzle 6 is positioned to communicate with a channel 9a, such as Figure 1b As shown. Optionally, a stop 7 or a second nozzle (not shown) is placed to cover another opening of channel 9a. Then, in step S4, moldable material 8 (e.g., in the liquid phase) is ejected from nozzle 6, as shown. Figure 1c As shown. The moldable material 8 enters the channel 9a and fills at least a portion of the channel 9a. The nozzle 6 may include a nozzle skirt 61 that allows the moldable material 8 to also fill the area outside the channel 9a between the skirt 61 and the outer surface 1a of the first layer 1. Similarly, the stops 7 may define an enclosed space between the stops, thereby allowing the moldable material 8 to also fill the area outside the channel 9a between the outer surfaces 2a of the second layer 2.

[0080] The moldable material 8 can be any suitable type of material that melts at elevated temperatures (typically above 100 degrees Celsius) but is solid at lower temperatures (typically below 80 degrees Celsius). For example, the moldable material is a plastic material such as polypropylene, polybutylene terephthalate, polycarbonate, conductive plastic materials, mixtures thereof, or blends thereof.

[0081] When the moldable material 8 is injected, it can be heated and can exhibit a lower viscosity than when it is solidified or solidified. For example, the moldable material 8 is heated so that it melts upon injection and is allowed to cool so that it solidifies within the channel 9a. This allows the moldable material 8 to fill the channel 9a and any spaces in fluid communication with the channel 9a during injection, such as the space between the first outer surface 1a and the nozzle skirt 61 or the space between the second outer surface 2a and the stop 7.

[0082] If compression molding is used, a moldable material (e.g., a sheet thereof) is placed inside the channel 9a, and two (optionally heated) baffles 7 are lowered from both sides to apply pressure to the moldable material, causing it to deform and fill the channel 9a to form an integrally formed retaining element. Therefore, the nozzle 6 is not strictly necessary when using compression molding. For example, steps S3 and S4 can be replaced by the following steps: introducing the moldable material into the channel and compressing (and optionally heating) the moldable material to form an integral retaining element.

[0083] In step S5, the moldable material 8 is allowed to solidify or solidify. Solidification or solidification can be passive or accelerated using active cooling of layers 1, 2, nozzle 6, and / or baffles. The solidified or cured moldable material forms an integrally formed retaining element 8', which is formed directly in the channel 9a by injection molding, wherein at least one channel 9a acts as part of the mold, such as... Figure 1d As shown.

[0084] Once the integrally formed retaining element 8' has been formed, the nozzle 6 and optional stop 7 can be removed, leaving the multilayer waveguide held together with the integrally formed retaining element 8'.

[0085] This process can be repeated for each channel 9a, 9b in the stack of layers 1 and 2, wherein a single-channel integral retaining element 8' is formed in each channel 9a, 9b. The benefit of multiple single-channel integral retaining elements 8' is that the clamping force pressing the layers together is more evenly distributed across the layers, which reduces the tendency for sometimes fragile layers to deform or break.

[0086] In some implementations, channels 9a and 9b are arranged with a relatively low spatial density in order to achieve proper fixation of layers 1 and 2.

[0087] Preferably, the spatial density of the channels 9a, 9b in which the integrally formed retaining element 8' is disposed is kept low, because overly densely packed channels 9a, 9b typically make waveguide design around the channels more difficult and may introduce excessive strain on layers 1, 2. The spatial density of the channels 9a, 9b filled by one or more integrally formed retaining elements 8' is determined as the number of channels 9a, 9b divided by the surface area of ​​the outer surfaces 1a, 2a (where the surface area can optionally be the operating wavelength). (represented by the square of the number of units). Spatial density can be lower than per... Six channels 9a and 9b, preferably less than each Four channels 9a and 9b, more preferably lower than each Two channels 9a and 9b, and preferably less than each One channel 9a, 9b. Even lower spatial densities can be used, and in some implementations, the spatial density is less than per 0.5 or 0.25 channels 9a and 9b.

[0088] The minimum spacing between two adjacent channels 9a and 9b can vary. In some implementations, the center-to-center distance between each pair of channels 9a and 9b is at least [value missing]. Divided by 6, preferably at least Divide by 4, and most preferably at least Divide by 2.

[0089] By changing the design of the nozzle skirt 61 and / or the stop 7, different types of integrally formed retaining elements 8' can be formed using the same general process. Figure 1d A single-channel integrally formed retaining element 8' extending through a channel is shown, but other types of integrally formed retaining elements 8' are also envisioned.

[0090] Turning Figure 3a and Figure 3b The illustration shows one embodiment in which two layers 1, 2 are held together by a single, integrally formed multichannel retaining element 8' extending through two channels 9a, 9b along the outer surface 1a of the first layer 1. The portion of the integrally formed retaining element 8' extending above the first outer surface 1a is referred to as the first structure, and it should be understood that although different “parts” of the single integrally formed retaining element 8' may be discussed, the integrally formed retaining element 8' is still a single component formed in a single molding process.

[0091] In this embodiment, the first structure is shaped like a substantially flat layer that at least partially covers the outer surface 1a of the first layer. Optionally, the substantially flat layer has a substantially constant thickness tc, which may be less than 10 mm or less than 5 mm. For example, the substantially flat layer has a thickness between 0.5 mm and 3 mm, such as between 1 mm and 2.5 mm.

[0092] In order to produce a retaining element 8' with this type of first structure integrally formed, a nozzle skirt 61 can be used in conjunction with two stops 7a, 7b, which extend to cover the inlets of the two channels 9a, 9b, and the stops 7a, 7b prevent the moldable material from forming the outer surface 2a of the second layer 2.

[0093] Therefore, using this nozzle skirt 61, a multi-channel integrally formed retaining element 8' can be formed, which has a large first structure covering a portion of the first outer surface 1a. For example, the first structure covers a large portion of the outer surface 1a of the first layer 1, such as at least 50% or at least 70% of the surface.

[0094] Figure 4a An example of a multi-channel integrally formed retaining element 8' is shown, which has a first structure covering a large portion of the outer surface 1a of the first layer. Although in Figure 4a Not shown, but integrally formed retaining element 8' extends through one or more (typically two or more, such as ten or more) channels to hold layers 1 and 2 together. With integrally formed retaining element 8' covering a large portion of the first outer surface, it is envisioned that integrally formed retaining element 8' can be used to protect the layers from environmental influences, such as protecting the layers from weather or protecting the layers from impacts with other objects.

[0095] In some embodiments, one or more antenna slots 13 communicating with the waveguide structure inside the multilayer waveguide device are arranged in one of the first layer 1 and the second layer 2. Without loss of generality, it is assumed that the antenna slots 13 are arranged in the first layer 1, such as... Figure 4a As shown. Therefore, the first structure of the integrally formed retaining element 8' can be used as an attenuation layer and / or an antenna pattern shaping layer to improve antenna performance. For example, the integrally formed retaining element 8' can be an electromagnetic absorbing material that reduces surface current and reflections caused by signals emitted through the antenna slot 13. As another example, the integrally formed retaining element 8' is made of a conductive material (e.g., a plastic material with conductive material additives), wherein the first structure of the integrally formed retaining element 8' can be shaped to enhance the antenna pattern. For example, the conductive material is provided with one or more ripples that can reduce surface current.

[0096] like Figure 4a As shown, the first structure of the integrally formed retaining element 8' may have one or more openings 85 to expose portions of the outer surface 1a of the first layer 1. For example, these openings 85 may be arranged to expose one or more antenna slots 13 and / or arranged in other locations.

[0097] In some embodiments, the electromagnetic bandgap (EBG) structure is formed by a first structure of an integrally formed holding element 8', which improves the antenna pattern. Therefore, the EBG layers for the antenna pattern are formed by the same integral structure that holds the layers together.

[0098] When multiple baffles 7a, 7b are used in each channel, the pattern formed on the outer surface 2a of the second layer 2 by the integrally formed retaining element 8' can be a distribution of small heads or beads of a cured or solidified moldable material, such as... Figure 4b As shown, Figure 4b The outer surface 2a of the second layer 2 is shown. The shape of each head or bead can be adjusted according to the shape of the stops 71a and 71b. For example, each head can be substantially dome-shaped, substantially polygonal, or any other shape.

[0099] As an addition or alternative to using a number of discrete heads or beads, the integrally formed retaining element 8' can also form a large, substantially flat layer on the outer surface 2a of the second layer. Thus, the second structure can be arranged to cover the outer surface 2a of the second layer. Figure 3c and Figure 3d This is illustrated schematically, wherein a large stop 71 covering at least two channels 9a, 9b is placed on the outer surface 2a of the second layer to allow the formation of an integrally formed retaining element 8', which has a first structure covering a large portion of the outer surface 1a of the first layer 1 and a second structure covering a large portion of the outer surface 2a of the second layer 2a.

[0100] In some embodiments, as described above, at least one of these layers includes an antenna aperture. Figure 4a and Figure 4b In the exemplary embodiment shown, the first layer acts as a radiating layer with an antenna aperture 13, wherein the outer surface of the second layer 2 faces rearward. Therefore, the multi-channel integrally formed retaining element 8' extending to cover a portion of the second outer surface 2a can be used to aid in heat dissipation, electrical insulation, and / or provide a structure for accommodating electrical components facing the PCB in a stacked configuration. Typically, to introduce / extract electromagnetic signals into / from the multilayer waveguide device, one or more feed ports (not shown) for communication with the PCB can be arranged in the second layer.

[0101] As a first example, the integrally formed retaining element 8' is made of an electrically insulating material, wherein the layer stack can be mounted against, for example, a PCB, wherein the second structure faces the PCB and remains electrically insulating. The second structure can, for example, form a support that facilitates mounting the PCB against the layer stack.

[0102] As a second example, the integrally formed retaining element 8' is made of a thermally conductive material, wherein the second structure of the integrally formed retaining element 8' can help dissipate heat from the layer stack to the structure behind the stack and / or dissipate heat from objects behind the stack (such as electrical components on a PCB) to the stack itself.

[0103] As a third example, the second structure of the integrally formed retaining element 8' includes at least one of a support for holding the PCB and a notch or opening configured to receive electrical components extending from the substrate of the PCB. This allows the PCB to be arranged close to the layer stack. For example, since these layers are made of metal or at least coated with metal, they are thermally conductive. By providing an opening in the integrally formed retaining element 8' to expose a portion of the second layer 2, the active components of the PCB can be arranged in thermal contact with the second layer 2, whereby the second layer, as well as other layers thermally connected to the second layer, can act as heat sinks for the active components.

[0104] As a fourth example, the second structure is made of a conductive material and is shaped to prevent resonance between the PCB and the second layer. For example, the second structure is provided with an electromagnetic bandgap (EBG) structure to suppress resonance. Thermally and / or conductive materials can also make the second structure serve as an electromagnetic interference (EMI) shield. Additionally, the conductive material can form channels for guiding electromagnetic signals to / from the PCB into the multilayer waveguide via ports located in the second layer.

[0105] Figures 3a-3d as well as Figure 4a and Figure 4b The alternatives shown are merely exemplary and can be combined in any way. For example, Figure 3b The integrally formed retaining element 8' can be reversed, so that the isolated head of the integrally formed retaining element 8' can be seen on the outer surface 1a of the first layer 1, and a large, substantially flat layer structure is present on the outer surface of the second layer 2. Furthermore, it is not necessary to use only a single multi-channel retaining element, and it is envisioned that… Figure 1d The single-channel integrally formed retaining element 8' shown may be formed in one or more (or all) channels 9a, 9b as an addition or alternative to one or more multi-channel integrally formed retaining elements 8' extending through one or more (or all) channels 9a, 9b.

[0106] Turning Figure 5This illustrates another configuration of the multi-channel integrally formed retaining element 8'. Here, the mesh structure of the multi-channel integrally formed retaining element 8' is arranged on the outer surface 2a of the second layer; however, it should be understood that the same mesh structure can also be used on the outer surface 1a of the first layer 1. Since the different channels are connected via elongated passages 84b' of the integrally formed retaining element 8', the structure is shaped like a mesh, net, or grid. Optionally, the heads 84a' of the integrally formed retaining element 8' can be arranged at the opening of each channel, wherein these heads 84a' are connected via one or more elongated passages 84b'. To form the desired mesh structure, the shape of the nozzle skirt or baffle is adjusted accordingly. Compared to a substantially flat layer structure, the mesh structure can be achieved with much less material, and it is envisioned that the mesh structure covers less than 50%, or less than 30%, of the outer surface of the layer on which it is disposed.

[0107] Figure 6a and Figure 6b An enlarged cross-sectional view of the retaining element 8' integrally formed according to some embodiments is shown.

[0108] Figure 6a A single-channel integrally formed retaining element 8' is shown, comprising two head portions 81' and 82', a first head portion 81' and a second head portion 82'. Each channel (which is formed by connecting through openings) passes through at least two layers 1 and 2, and it is envisioned that the opening size (e.g., opening diameter) D1, D2 of each through opening can be constant or vary as the through opening extends through its corresponding layer 1 or 2. Figure 6a In one embodiment, the through opening in the first layer 1 has an approximately constant size D1. To reliably hold layers 1 and 2 using an integrally formed retaining element 8', the integrally formed retaining element 8' may therefore include a first head portion 81' that protrudes beyond the outer surface 1a of the first layer and has a size greater than D1. Thus, the first head portion 81' extends beyond the outer surface 1a of the first layer, thereby partially covering the outer surface 1a near the channel.

[0109] On the other hand, the size D2 of the through opening in the second layer 2 varies, characterized in that the size D2 is larger closer to the outer surface 2a of the second layer and smaller further away from the outer surface 2a. In this way, the second head portion 82' of the integrally formed retaining element 8 can be completely integrated into the second layer 2, so that the second head portion 82' does not protrude outward beyond the outer plane of the outer surface 2a of the second layer.

[0110] In other words, the integrally formed retaining element 8' here includes two head portions 81', 82', which are connected via a neck portion 83', wherein the size of the neck portion 83' in a plane parallel to the layer is smaller than the size of the first head portion 82' and the second head portion 83'. The neck portion 83' also extends through the minimum opening size of each through opening, while the size of the first head portion 81' is larger than the minimum size D1 of the through opening in the first layer 1, and the size of the second head portion 82' is larger than the minimum size D2 of the through opening in the second layer.

[0111] In some implementations, each dimension D1, D2 of the through opening is at least 1 mm or at least 1.5 mm.

[0112] This configuration of the integrally formed retaining element 8' will reliably hold layers 1 and 2 together, preventing accidental breakage. Typically, for the thinner layers 1 and 2, a through-hole of constant size is preferred, such as... Figure 6a The through opening in the first layer 1 is preferred, while for thicker layers, through openings of varying sizes are preferred, such as... Figure 6a The through-opening in the second layer. This is because achieving a through-opening with varying opening sizes in a thin layer can be challenging.

[0113] Turning Figure 6b An enlarged cross-sectional view of a multi-channel integrally formed retaining element 8' according to some embodiments is shown. The multi-channel integrally formed retaining element 8' has a first structure extending between two or more channels (and forming a substantially flat surface, for example, on the outer surface of the first layer 1). As shown, the head portion 81' of the integrally formed retaining element 8' is constituted by the first structure of the multi-channel integrally formed retaining element 8' extending between different channels. To prevent the second layer 2 from detaching from the first layer 1 and the integrally formed retaining element 8', a second head portion 82' is formed to hang over the second outer surface 2a.

[0114] Therefore, when the holding element 8' formed by multiple channels enters two or more channels, the same head portion 81' is shared among multiple channels, while each channel may have a separate second head portion 82'.

[0115] exist Figures 7a-7c The image shows a cross-sectional view of a three-layer multilayer waveguide device. As mentioned above, a multilayer waveguide may include more than two layers 1, 2, and 3, and... Figure 7aIn the illustrated embodiment, the multilayer waveguide comprises three layers 1, 2, and 3, namely, a first layer 1, a second layer 2, and a third layer 3, with the third layer 3 arranged adjacent to the first layer 1 and opposite to the second layer 2. Each layer has through openings 21a and 31a, which, when layers 1, 2, and 3 are held together, form channels 9a and 9b extending to the outer surfaces of the outermost layers (here, the second layer 1 and the third layer 3).

[0116] Similar to the use of only two layers 1, 2, one or more nozzles 6a, 6b (optionally having corresponding skirts 61a, 61b) are used to communicate with each channel 9a, 9b, thereby forming the integrally formed retaining elements 8'a, 8'b by injecting and solidifying the moldable material fluid 8, as shown. Figure 7b and Figure 7c As shown. In this example, two separate single-channel integrally formed holding elements 8'a and 8'b are formed, but it is envisioned that a multi-channel integrally formed holding element 8' can be formed in a similar manner.

[0117] Figures 7a-7c The layers depicted include a structure that forms a waveguide when these layers are held together. In this example, waveguide 33 is formed by providing an elongated aperture that forms a channel in the first layer 1 located between the second layer 2 and the third layer 3. Metasurfaces 4 are disposed on the inner surfaces of the second metal layer 2 and the third metal layer 3 to surround the channel in the first layer 1. Additionally, in the regions overlapping with the channel in the first layer 1, the second layer 2 and the third layer 3 have no metasurfaces 4, thus the waveguide 33 extending parallel to layers 1, 2, and 3 is formed by the channel in the first layer, the second layer 2 and the third layer 3, and the metasurfaces 4 disposed on each of the second layer 2 and the third layer 3. Optionally, a center conductor 34 is disposed inside the channel in the first layer 1, thereby realizing a coaxial waveguide channel. The center conductor can be suspended by support pillars extending from the periphery of the channel.

[0118] This type of three-layer waveguide device can be implemented using very thin layers. For example, the total thickness of at least one of layers 1, 2, and 3 is less than [amount missing]. Divide by 4, below Divide by 5 or less Divide by 6. Preferably, the total thickness of each layer 1, 2, and 3 is less than 6. Divide by 4, below Divide by 5 or less Divide by 6.

[0119] The thickness of each individual layer is preferably less than 1 mm, although greater thicknesses are possible. In some embodiments, the thickness of each layer is 500 mm. and 300 Between. All layers can have the same thickness, but it is also envisioned that metal layers 1, 2, and 3 can have different thicknesses. For example, the second layer 2 and the third layer 3 could have thicknesses between 500 and 600. and 300 The same thickness between them, and the first layer 1 is thinner, having a thickness of 50. and 200 The thickness between, for example, about 100 The exemplary thicknesses described above are suitable for simple and cost-effective manufacturing, but are merely exemplary and can vary, for example, depending on the operating frequency, outside these ranges. The exemplary thicknesses described above are suitable for operating frequencies of approximately 77 GHz. These exemplary thicknesses are also applicable to… Figure 1a , Figure 1d The waveguide shown is a two-layer waveguide, and it can also be used in multi-layer waveguide devices with more than three layers.

[0120] When at least three layers 1, 2, and 3 are used in a layer stack to form a multilayer waveguide, it is no longer necessary for the holding element 8' of each integrally formed waveguide to hold all the layers together. For example, as in the reference... Figure 8a and Figure 8b As described, for a three-layer device, it is envisioned to use at least two integrally formed retaining elements 8''a, 8''b, one of which is integrally formed retaining element 8''a securing the first layer 1 and the second layer 2, while the other integrally formed retaining element 8''b securing the third layer 3 and the first layer 1.

[0121] exist Figure 8a In the middle, the third layer 3 has a recess 32 that communicates with the channel 9a formed by the through openings 11a and 21a in the first layer 1 and the second layer 2. The recess 32 is optional, and can be omitted if the outlet opening in the first layer 1 has a varying opening size, which allows the integrally formed retaining element 8''a to hold the first layer 1 and the second layer 2 together without extending beyond the boundaries of the first layer 1 (see...). Figure 6a The second layer has a through-opening that allows for retention using a retaining element formed integrally with its ends flush with the layer. Then, as... Figure 8b As shown, the integrally formed retaining element 8''a is formed to pass through the channel 9a to hold the first layer 1 and the second layer 2 together.

[0122] The third layer 3 can now be secured to the first layer 1 and the second layer 2 by means of a second integrally formed retaining element 8''b, which is arranged to hold the third layer 3 to the first layer 2, as follows: Figure 8b As shown.

[0123] exist Figure 8bIn this process, two integrally formed retaining elements 8''a and 8''b have been formed. Each integrally formed retaining element 8''a and 8''b holds at least two layers together, and for at least one of the integrally formed retaining elements 8''a and 8''b, the channel formed by the two layers held together therebetween serves as the mold for that integrally formed retaining element 8''a and 8''b; additionally, the other layer serves as a stop. For example, when using injection molding... Figure 8b When the retaining element 8''b is integrally formed in the mold, the nozzle injects fluid (e.g., molten or light / heat curable) moldable material into the mold, which is formed by the through opening 31 of the third layer 3, the through opening 11 of the first layer 1 and the second layer 2, and the recess 22 of the optional second layer.

[0124] Turning Figure 9 An exemplary multilayer waveguide with five layers 1, 2, 3', 3'', 3''' is shown according to some embodiments. The multilayer waveguide device includes a first layer 1 and a second layer 2 acting as the outermost layers, wherein three intermediate layers 3', 3'', 3''' are arranged between the first layer 1 and the second layer 2. For example, by providing matching channels through all the intermediate layers 3', 3'', 3''', a relatively large waveguide 33 (with) can be achieved. Figure 8b (In comparison). Optionally, a center conductor 34 is also introduced to make it a coaxial waveguide.

[0125] Regardless of the number of layers 1, 2, 3', 3'', 3''', one or more channels extending through two or more layers 1, 2, 3', 3'', 3''' can be formed through channels in layers 1, 2, 3', 3'', 3''', where these layers are held together by one or more integrally formed retaining elements 8' formed in each channel, where each channel has been formed as part of a mold for forming the integrally formed retaining element 8'. Therefore, various waveguide structures can be implemented using layers 1, 2, 3', 3'', 3'''. For example, as... Figures 7a-7c Multiple three-layer stacks can be stacked on top of each other, which allows for complex waveguide routing along and laterally to the layer plane by guiding electromagnetic radiation up / down between the three-layer stacks.

[0126] Those skilled in the art will recognize that the invention is by no means limited to the preferred embodiments described above. Rather, many modifications and variations are possible within the scope of the appended claims. For example, various numbers of layers can be used, and these layers can be held together by a single multi-channel integrally formed retaining element or by multiple single-channel or multi-channel integrally formed retaining elements. Furthermore, when using more than two layers, it is contemplated that each integral retaining element need not extend through all layers. Instead, at least two integral retaining elements can be used, each integral retaining element extending through a separate subset of layers. Each subset includes at least one common layer.

[0127] Such and other obvious modifications must be considered within the scope of the invention, as defined by the appended claims. It should be noted that the embodiments mentioned above are illustrative and not limiting of the invention, and those skilled in the art will be able to devise many alternative embodiments without departing from the scope of the appended claims. Any reference numerals placed between parentheses in the claims should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps other than those listed in the claims. The words "a" or "an" preceding an element do not exclude the presence of a plurality of such elements.

Claims

1. A multilayer waveguide assembly, comprising: At least two layers (1, 2) including a first layer (1) and a second layer (2), wherein each of the first layer (1) and the second layer (2) includes at least one through opening (11a, 11b, 21a, 21b), wherein the at least two layers (1, 2) are arranged together such that the through opening (11a, 21a) forms a corresponding channel (9a) extending from the outer surface (1a) of the first layer (1) to the outer surface (2a) of the second layer (2). Wherein, the at least two layers (1, 2), when arranged together, form a waveguide for the operating wavelength; and An integral retaining element (8') extends through the at least one channel (9a), wherein the integral retaining element (8') has been formed directly in the channel (9a) by a molding process, wherein the at least one channel (9a) serves as part of a mold.

2. The multilayer waveguide assembly according to claim 1, wherein, Each through opening includes a corresponding throat segment with a minimum opening size (D1, D2), and wherein the integral retaining element (8') includes a first head portion (81') at the first layer (1) and a second head portion (82') at the second layer (2), wherein the first head portion (81') and the second head portion (82') are connected via a neck portion (83'). The neck portion (83') extends through the throat section, and the dimensions of the first head portion (81') and the second head portion (82') are greater than the minimum opening dimensions (D1, D2) in the respective throat sections.

3. The multilayer waveguide assembly according to claim 1 or claim 2, wherein, The first layer (1) and the second layer (2) each include at least two through openings (11a, 11b, 21a, 21b) to form at least two channels (9a, 9b), and The integral retaining element (8') includes a first structure extending between at least two channels (9a, 9b) on the outer surface (1a) of the first layer (1), and wherein the integral retaining element (8') extends through the at least two channels (9a, 9b).

4. The multilayer waveguide assembly according to any one of the preceding claims, wherein, The first layer (1) and the second layer (2) each include at least two through openings (11a, 11b, 21a, 21b) to form at least two channels (9a, 9b), and The integral retaining element (8') includes a second structure extending between at least two channels (9a, 9b) on the outer surface (2a) of the second layer (2).

5. The multilayer waveguide assembly according to claim 4 when dependent on claim 3, wherein, The first structure and the second structure are attached via the at least two channels (9a, 9b).

6. The multilayer waveguide assembly according to claim 4 or claim 5, wherein, The second structure forms a support, which is configured to be mounted against a PCB to hold the second layer (2) of the multilayer waveguide assembly at a distance from the PCB.

7. A multilayer waveguide system, comprising a PCB and a multilayer waveguide assembly according to any one of claims 4-6, wherein, The multilayer waveguide assembly is mounted on the PCB using the bracket that contacts the PCB.

8. The multilayer waveguide assembly according to any one of claims 3-7, wherein, At least one structure forms a generally flat layer.

9. The multilayer waveguide assembly according to claim 8, wherein, The substantially flat layer covers at least 50% of the outer surface (1a, 1b) of the first layer (1) or the second layer (2), and preferably covers at least 70% of the outer surface (1a, 1b).

10. The multilayer waveguide assembly according to claim 8 or claim 9, wherein, The first layer includes one or more antenna apertures, wherein the first structure forms a substantially flat layer, and wherein the substantially flat layer includes at least one opening (85) surrounding the one or more antenna apertures (13).

11. The multilayer waveguide assembly according to any one of claims 3-10, wherein, The first layer and the second layer each include at least three through openings (11a, 11b, 21a, 21b) to form at least three channels (9a, 9b), and At least one of the structures is a mesh extending between the at least three channels (9a, 9b).

12. The multilayer waveguide assembly according to claim 1 or claim 2, further comprising: The third layer (3) includes at least one through opening (31c). The first layer (1) further includes an additional through opening (11c), and The third layer is arranged on the outer side (1a) of the first layer (1), opposite to the second layer (2), such that the through opening of the third layer (3) forms an additional channel extending from the outer surface (3a) of the third layer (3) to the inner surface (1b) of the first layer (1). The multilayer waveguide further includes: An additional integral retaining element (8''b) extends through the additional channel, wherein the additional integral retaining element (8''b) has been formed directly in the second channel by a molding process, wherein the additional channel (9) and the second layer (2) serve as part of the mold.

13. The multilayer waveguide assembly according to any one of the preceding claims further comprises: At least one intermediate layer (31a, 31b, 31c) is arranged between the first layer (1) and the second layer (2), wherein the at least one intermediate layer includes a through opening, the through opening together with the through openings (11a, 11b) of the first layer (1) and the second layer (2) to form the channel (9a).

14. The multilayer waveguide assembly according to any one of the preceding claims, wherein, The first layer and the second layer each include at least two through openings (11a, 11b, 21a, 21b) to form at least two channels, and wherein the multilayer waveguide assembly includes: At least two separate integral retaining elements (8'a, 8'b), each integral retaining element extending through the corresponding channel (9).

15. The multilayer waveguide assembly according to any one of the preceding claims, wherein, The space density of a channel filled with the same integral retaining element (8') or different integral retaining elements (8'a, 8'b) is less than that per 4 channels, preferably less than each Three channels, preferably less than each Two channels, and preferably less than each One channel.

16. The multilayer waveguide assembly according to any one of the preceding claims, wherein, At least one through opening (11a, 21a) has an opening size that increases in the direction toward the respective outer surface (1a, 2a).

17. The multilayer waveguide assembly according to any one of the preceding claims, wherein, At least one of the layers (1, 2, 3) includes a metasurface (4) disposed on a surface facing another layer, wherein the metasurface (4) defines the waveguide and prevents the operating wavelength from being used. Electromagnetic radiation propagates between the layers in directions other than along the waveguide.

18. The multilayer waveguide assembly according to claim 17, wherein, The metasurface (4) is a textured surface comprising multiple thick segments (41) and multiple thin segments (42).

19. The multilayer waveguide assembly according to any one of the preceding claims, wherein, The integral retaining element (8') is made of a plastic material, such as polypropylene, polybutylene terephthalate, polycarbonate, conductive plastic material, mixtures thereof, or blends thereof.

20. A method for manufacturing a multilayer waveguide assembly, comprising: Provide (S1) at least two layers (1, 2), a first layer (1) and a second layer (2), wherein the first layer (1) and the second layer (2) each include at least one through opening (11a, 11b, 21a, 21b). The at least two layers (1, 2) are held together (S2) such that the through openings (11a, 11b, 21a, 21b) form at least one channel extending from a first aperture in the outer surface (1a) of the first layer (1) to a second aperture in the outer surface (2a) of the second layer (2), wherein the at least two layers (1, 2) form a working wavelength when arranged together. waveguide; as well as An integral retaining element (8') is formed extending through the at least one channel (9a), wherein the integral retaining element (8') is formed directly in the channel (9a) by a molding process, wherein the at least one channel (9a) serves as part of the mold.

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