Antenna device

Abstract

The present disclosure relates to an antenna arrangement (1) for automotive radar applications, comprising a printed circuit board (2) having a front face (3) and a rear face (4) and an electronic component (5) interconnected to the printed circuit board (2), and an antenna layer (6) having a front face (7) and a rear face (8) interconnected to the front face (7) of the printed circuit board (2). At least one waveguide hole (9) is interconnected to the front face (7) of the antenna layer (6) and communicatively connected to the electronic components (5) by at least one waveguide channel (10), where the at least one waveguide channel (10) comprises an electrically conductive surface (11) for guiding an electromagnetic field between the electronic components (5) and is formed by a recess (12) arranged between the back face (8) of the antenna layer (6) and the front face (3) of the printed circuit board (2).

Description

Technical Field

[0001] The present disclosure relates to antenna arrangements for use, for example, in automotive radar applications. Background Art

[0002] WO2022122319A1, published on June 16, 2022 in the name of the applicant, relates to an antenna device comprising a printed circuit board and an electronic component arranged thereon. The antenna device comprises at least two separate antenna elements, which are interconnected to an electronic component configured to send and receive signals. The antenna elements each include at least one waveguide channel interconnected in the antenna assembly. A first waveguide aperture is arranged at the back of the antenna assembly. The first waveguide aperture is interconnected to the electronic component and is configured to send and / or receive signals. The second waveguide aperture is arranged at the front of the waveguide assembly and is also configured to send and / or receive signals.

[0003] WO2021163381A1, published on August 19, 2021 in the name of Veoneer US Inc., relates to a radar sensor assembly / module, in particular a radar sensor assembly / module for a vehicle, comprising a plurality of waveguides. Each of the plurality of waveguides is defined by a waveguide groove. The groove may be positioned to extend along the axis of each of the plurality of waveguide grooves. Each of the waveguides may be further defined at least in part by a periodic feature and a plurality of periodic signal limiting structures, the periodic feature extending back and forth along at least a portion of its corresponding waveguide in a periodic manner, a first periodic signal limiting structure of the plurality of periodic signal limiting structures may extend adjacent to a first side of each of the plurality of waveguides, and a second periodic signal limiting structure may extend along a second side of each of the plurality of waveguides opposite to the first side.

[0004] WO2022053114A1, published on March 17, 2022 in the name of Conti Temic Microelectronic GmbH, relates to a radar system for detecting the surrounding environment, the radar system having a printed circuit board and a molded part, the printed circuit board having at least one high-frequency component and at least one direct transmitting or receiving element, the molded part having one or more separate antennas for sending and / or receiving radar signals on the upper face of the molded part, wherein the connection between at least one transmitting or receiving element of the high-frequency component and at least one separate antenna on the upper face of the molded part is at least partially implemented by a hollow inner waveguide. The transmitting / receiving element of the high-frequency component is emitted in the direction of the printed circuit board, and the printed circuit board is transparent to radar waves in the region. The molded part is electrically connected to the printed circuit board by soldering and / or conductive bonding. The printed circuit board feeds the waveguide from a transparent position of the printed circuit board, and the molded part consists of a single-layer plastic part that is at least partially metallized.

[0005] US20220196792A1, published on June 23, 2022 in the name of Robert Bosch GmbH, relates to a method for manufacturing a radar sensor. In the method, a circuit board is provided. The surface of the circuit board is equipped with a radar transceiver. A waveguide structure made of a plastic material is provided. A waveguide channel is formed, which includes at least one metal conductively coated side wall and an open side in the waveguide structure. The waveguide structure is soldered to the surface of the circuit board, and the open side is oriented in the direction of the circuit board.

[0006] US20210249784A1, published on August 12, 2021 in the name of Veoneer US Inc., relates to an antenna and / or waveguide assembly for a vehicle, such as a radar sensor antenna assembly, and an associated signal limiting structure. In some embodiments, the assembly may include an antenna block defining one or more waveguides. A conductive layer may be coupled to the antenna block to at least partially form a wall of the waveguide. The assembly may include one or more periodic structures that may be operably coupled to the waveguide, each of the one or more periodic structures may include a first elongated opening and a first series of repeating grooves extending at least substantially transverse to the first elongated opening, wherein each of the first series of repeating grooves is spaced apart from an adjacent groove in the first series of repeating grooves along the first elongated opening. Summary of the invention

[0007] Antenna devices are widely used components for communication devices and radar applications, for example in the automotive industry, or form part of assisted or automated driving systems. For these applications, signals with millimeter wave frequencies are typically used. In addition to antenna performance, such as antenna gain and efficiency, which are both critical parameters as they directly influence the overall system performance, a mechanically simple setup is also required in view of the huge production quantities of these antenna devices.

[0008] The antenna device can be designed as a printed circuit board antenna (PCB antenna), which is usually used at lower frequencies, but can also be used at millimeter wave frequencies. However, they typically have disadvantages in terms of performance. More specifically, PCB antennas usually include planar metal structures as radiating elements. They are usually implemented on top of a dielectric substrate layer or integrated in a dielectric substrate layer. These radiating elements are realized by connecting an additional planar structure (i.e., a transmission line such as a microstrip line, a coplanar waveguide, a stripline, which guides the signal from the chip to the radiating part) to the chip or an electronic component intended to generate / receive the power (signal) to be sent / received. Due to the specific dielectric properties of the substrate material, these antenna systems tend to have very large losses at millimeter wave frequencies (especially for frequencies above 60 GHz). These losses greatly reduce the antenna efficiency / performance and at the same time increase the power that needs to be dissipated within the system.

[0009] As an alternative to PCB antennas with the previously mentioned disadvantages, air-filled waveguide antennas have been developed. The general air-filled waveguide used at microwaves and millimeter waves is a hollow conductive tube that can guide electromagnetic signals from point A to point B with negligible losses (depending on the metal conductivity). Standard millimeter wave frequency waveguide components are typically manufactured using advanced processing techniques with very low tolerance requirements, such as high-precision milling, micromachining, etc. However, these technologies show limitations because air-filled waveguide antennas typically require a complex power distribution / synthesis network connecting the antenna feed point to the radiating structure. Both the radiating structure and the feed network typically include specific features that require low tolerances (on the order of tens of microns).

[0010] Aspects of the present disclosure overcome these manufacturing limitations / disadvantages based on the considerable performance advantages of waveguide technology over, for example, printed circuit boards (PCBs).

[0011] With cost-effective production in mind, one goal is to achieve designs and techniques for implementing MIMO antenna arrays that can be manufactured using only a minimum number of stacked layers (parts). In view of the above-mentioned advantages of waveguide technology in terms of performance, and given the tight tolerance requirements of manufacturing, aspects of the present disclosure involve a combination of innovative radio frequency and mechanical design with advanced manufacturing to implement high-performance millimeter-wave frequency waveguide antennas and components, especially for automotive applications with at most only a single antenna layer.

[0012] The antenna device for automotive radar applications according to the present disclosure typically includes a printed circuit board (PCB) having a front and a back side and electronic components interconnected to the printed circuit board. As the electronic component, a radar chip is typically used, such as, for example, a monolithic microwave integrated circuit (MMIC), which includes a plurality of circuits integrated into a small package for operation at microwave frequencies. These MMICs are typically arranged directly on the front or back side of the printed circuit board. Alternatively, the electronic component can be interconnected with the printed circuit board or the electronic component intended to generate / receive the power (signal) to be sent / received by an additional planar structure (i.e., a transmission line such as, for example, a microstrip line, a coplanar waveguide or a stripline, which guides the signal from the chip to the radiating part).

[0013] In order to guide the signal from the electronic component to at least one waveguide hole configured for sending and / or receiving the signal, the antenna device typically includes an antenna layer. Good results regarding signal transmission can be achieved when the antenna layer has a front side and a back side, the back side being interconnected to the front side of the printed circuit board. In a variant, the antenna layer is additionally configured to serve as a radome that protects at least the printed circuit board and / or components within the antenna device from environmental influences. Therefore, the antenna layer is at least partially made of a material that resists environmental influences, such as a material that does not absorb moisture. In a variant, the back side of the antenna layer is in direct contact with the front side of the printed circuit board (PCB) or a coating on the front side of the printed circuit board. The distance between the back side of the antenna layer and the front side of the PCB may be substantially zero, or in the form of an air gap that is typically less than the length of the wavelength (λ).

[0014] Alternatively or in addition, electronic components in the form of chips (MMICs) can be embedded in printed circuit boards. The chips can thus be embedded in one of the layers of substrate material. Such substrate materials typically consist of printed circuit board material or any other material suitable for embedding chips (silicon, ceramics, glass, molding compounds).

[0015] The electromagnetic signal may be fed from the chip to at least one waveguide channel inside the antenna layer via a planar transition line or a three-dimensional transition line in the form of a substrate integrated waveguide (SIW), a dielectric loaded embedded waveguide and / or an air filled embedded waveguide. This may be the case whether the chip is embedded in the printed circuit board or mounted on the top or bottom of the printed circuit board.

[0016] In another variant, the back side of the antenna layer may be interconnected to the front side of the printed circuit board via at least one intermediate layer. In a variant, the intermediate layer may be in the form of a coating or an additional antenna layer. Between the front side of the PCB and the back side of the antenna layer, a plate-shaped intermediate layer may be arranged. The front side of the intermediate layer may face the back side of the antenna layer. The back side of the intermediate layer may face the front side of the PCB. The waveguide hole is typically interconnected to the front side of the antenna layer and is communicatively connected to the electronic component via a waveguide channel. The waveguide channel may be at least partially arranged in the intermediate layer, extending from the back side of the intermediate layer to the front side.

[0017] The intermediate layer may also include several parts or layers, for example including at least one front layer and a back layer connected thereto. The intermediate layer may include a back layer and a plate-shaped front layer. The back layer and the front layer are typically connected along a parting plane. In this variation, the front side of the intermediate layer facing the back side of the antenna layer is arranged at the front layer. In this variation, the back side of the intermediate layer facing the front side of the PCB is arranged at the back layer. The scattering surface may be implemented in the form of an array of cavities close to the waveguide channel in the back side of the antenna layer and / or the back side of the intermediate layer and / or the back side of the front layer of the intermediate layer, as described in more detail in the description below. The scattering surface is typically arranged so as to reduce or eliminate reflections that occur in the presence of a change in the medium, the change in the medium being typically equal to the change in the dielectric constant. The scattering surface may reduce or eliminate reflections between the front side of the antenna layer and the back side of the antenna layer. Alternatively or in addition, the scattering surface may reduce or eliminate reflections between the back side of the antenna layer and an external component (e.g., a bumper in an automotive application) that is spaced a certain distance from the antenna device.

[0018] Good results can be achieved when the signal is fed from an electronic component, typically a radar chip in the form of an MMIC, into at least one waveguide channel. Good results can be achieved when the waveguide channel is designed as a tubular channel, in which one channel wall is formed by the front side of the PCB or the front side of the intermediate layer, and the other channel wall is formed by a recess arranged at the back side of the antenna layer or forming part of the back side of the antenna layer. Good results can be further achieved when the waveguide channel comprises at least a waveguide cross section selected from the group of the following geometric shapes or combinations thereof: rectangular, rhombus, elliptical, trapezoidal, half-moon, etc. The signal is typically fed into at least one waveguide hole via at least one waveguide channel. At least one waveguide hole can be designed as a slot antenna or a horn antenna integrated in, on or behind the front side of the antenna layer. In order to obtain a smooth broadband impedance transition from the waveguide channel through the antenna layer, antenna layer materials with a lower dielectric constant (dk ~ 1-6) are preferred.

[0019] In order to receive or send signals, at least one waveguide hole is typically interconnected to the front side of the antenna layer and is communicatively connected to the electronic component through at least one waveguide channel. In a variant, at least one waveguide channel is designed as a rectangular waveguide channel, which can be regarded as a tube typically consisting of four walls. The waveguide channel is typically formed by a recess arranged between the back side of the antenna layer and the front side of the printed circuit board. If at least the wall of the recess is designed with a draft angle, good results can be obtained regarding the manufacture of the waveguide channel. In order to be able to guide electromagnetic signals, at least one waveguide channel typically includes a conductive surface for guiding the electromagnetic field between the electronic component and the at least one waveguide hole. For electrical conduction, the antenna layer, which can also be used as a cover (radome), can be metallized on the back side to produce a conductive surface. The waveguide channel can be formed by placing the recess directly in direct contact with the metallized front side of the PCB or the back side of the antenna layer and the conductive intermediate layer between the PCB.

[0020] By arranging the back side of the antenna layer on the front side of the printed circuit board and supported by the back layer or the housing, a particularly simple design can be achieved. The printed circuit board can be arranged between the antenna layer and the back layer or the housing in a sandwich-type structure. Good results can be achieved when the antenna layer and the back layer or the housing form an integral housing of the antenna device, which surrounds the PCB and protects the internal components of the antenna device from environmental influences. For easy and positionally accurate assembly, the antenna layer, the PCB and the back layer or the housing can be assembled via a connecting element protruding from the back side of the antenna layer. The connecting element can be designed as a pin, which in the assembled state protrudes through a drilled hole in the PCB and is received by a receiving opening in the back layer or the housing.

[0021] The main advantage of this design compared to known designs is lower cost, since it is not necessary for the antenna layer to be made of several separate layers. In addition, no additional separate radome is required. Due to the reduced number of antenna layers compared to known designs, the thickness of the overall antenna device can be significantly reduced. In addition, in known designs, the radome is usually placed at a distance between λ / 4 and λ (1mm-4mm at 77Ghz) relative to the PCB, which distance can also be removed. This makes the design suitable, for example, for small sensors used as corner radars, front radars, side radars or rear radars in automotive applications where cost is extremely important. The antenna layer does not have to be essentially flat. If appropriate, the antenna layer can be at least partially skeletonized to reduce the contact surface between the antenna layer and the printed circuit board. This is advantageous because the minimized contact surface increases the surface pressure of the contact surface and thus leads to a more precise alignment of the antenna layer and the printed circuit board.

[0022] Once the antenna layer is interconnected with the printed circuit board or arranged directly on the printed circuit board, a highly accurate mold parting line is desired to have a minimal effect on the propagation of the electromagnetic signal (i.e., minimal losses and mismatches). The design of the waveguide channel and the antenna layer can be optimized to be compatible with a variety of joining technologies. In a variant, the front side of the printed circuit board and the back side of the antenna layer are substantially flat. This can be particularly advantageous because the preferred joining technology may include at least one of the following groups: soldering, welding, gluing (both conductive and non-conductive), clamping, or a combination thereof. In a variant, the antenna layer can be used as a housing for the radar device, whereby the printed circuit board is sealed by means of a plate-shaped back cover.

[0023] The antenna layer is typically made of a metallic material at least in part and / or includes a metallized layer forming a conductive surface. In the case where the antenna layer is made by injection molding of at least one plastic material, the back layer and / or the recess is typically metallized by a conductive material. Alternatively or in addition, the antenna layer may be made of a metallized plastic and / or any other material that is conductive at the surface. Techniques such as high-precision plastic injection molding can be used, and if necessary, a metallization process can be used. For variations in which additional coatings or metallized layers are required, a typical coating process includes metallizing the back of the antenna layer by applying, for example, a physical vapor deposition (PVD) coating, a flame spray coating, or electroplating or electroless plating. Alternatively or in addition, injection molding can be used, whereby the conductivity of the antenna layer can be increased by using an injection molding technique (film injection molding) of any additional conductive part (e.g., a metal sheet or a metal film). Overmolding can also be applied, whereby a conductive material (plastic filled with conductive fillers) can be overmolded to another non-conductive plastic material. With overmolding, also known as insert molding, a metal insert may be overmolded by molten plastic injected into a mold, forming the antenna layer.

[0024] When the recess is at least partially formed by a deepening in the back side of the antenna layer, good results can be achieved with respect to manufacturability. This is particularly beneficial for injection molding or die casting, as the part can be easily demoulded. The recess can be formed at least partially by a deepening and / or a protrusion in the back side of the antenna layer. As an alternative to the protrusion or in addition to the protrusion, the recess can be arranged in the back side of the antenna layer. The EBG structure is formed by a protrusion extending over the back side of the antenna layer and / or a planar metal structure on the front side of the printed circuit board. The protrusion can be made integrally with the antenna layer, laterally delimiting the recess and forming an electromagnetic bandgap structure with the front side of the printed circuit board. Alternatively or in addition, a planar metal structure comprising a plurality of patches can be arranged on the front side of the PCB, the patch laterally delimiting the recess and forming an electromagnetic bandgap structure with the protrusion or the back side of the antenna layer. The antenna layer may include a ridge arranged in the recess and extending substantially along the waveguide channel. The ridge can be arranged in the recess of the waveguide channel to reduce the overall size of the waveguide channel. Alternatively or additionally, the waveguide channel may be implemented in the form of a coaxial waveguide by including a metal strip at the center of the waveguide channel for further reducing the size.

[0025] Another aspect of the present disclosure is the use of artificial magnetic conductors (AMCs) in the context of antenna devices. AMCs are approximations of perfect magnetic conductors (PMCs), which exist only in theory but can be approximated within a limited bandwidth by AMCs. AMCs prevent the transmission of magnetic fields parallel to the surface of the material. AMCs can be generated by periodic or random patterns. On a PCB, this can be implemented by periodically arranging metal patches or by arranging periodic cavities in an all-metal surface (the complementary case of patches).

[0026] The basic theory of AMC is perfect magnetic conductor (PMC), which is an idealized material that does not allow magnetic fields to propagate inside it. In the context of the antenna device, artificial magnetic conductors can achieve two purposes. Arranging the AMC structure on the front side of the PCB (which faces the back side of the antenna layer in the installed state) can form an electromagnetic band gap (EBG) structure between the AMC structure and the back side of the antenna layer. The EBG structure avoids the undesired propagation of electromagnetic waves outside the defined waveguide channel. Alternatively or in addition, the portion of the AMC structure that can form a waveguide channel together with the recess of the antenna layer in the installed state can allow the height of the waveguide channel to be reduced, thereby reducing the height / depth of the recess in the antenna layer, and thereby reducing the overall height of the antenna device.

[0027] With the AMC structure arranged on the front side of the PCB, the waveguide channel can be designed as a half-mode waveguide. The basic concept of a half-mode waveguide is to halve the height of the waveguide channel. In order to be able to halve the height and still be able to guide the signal, the concept is to mirror the electric field of the signal with an artificial magnetic conductor (AMC). The patch may be, for example, rectangular, circular or pentagonal, hexagonal, elongated, elliptical in shape. The patches may be placed on the front side of the PCB in a linearly symmetrical, slidingly symmetrical or random pattern. An alternative variant for producing an AMC is to arrange an all-metal plane with, for example, polygonal holes or protrusions in the form of cavities on the back side of the antenna layer, rather than having a metal patch on the front side of the PCB.

[0028] The lateral distance between the patches relative to each other (periodicity) is typically chosen with respect to the emission wavelength. The size of the patches is related to the guided wavelength. The wavelength can be calculated as follows: λ 0 = free air wavelength ε r PCB = Dielectric constant of PCB substrate

[0029] Periodicity is usually in λ 0 / 8-2λ 0 The patches are typically arranged in a collinear array, where the array forms rows and columns. Between adjacent columns, the patches are arranged with a first periodicity P x spaced apart, and between adjacent rows there is a second periodicity P y Spaced apart. As a result, in a top view, on the front side of the PCB, the patches can form a matrix. In addition, the arrays can be offset relative to each other. When the patches within one array are spaced apart by a distance equal to the periodicity, adjacent arrays can be offset relative to each other by a distance equal to P / n, where n is a natural number. This produces a staggered design. The advantage of the periodic pattern of the patches is that even if the antenna layer is misaligned relative to the printed circuit board (laterally shifted or angularly shifted), the magnetic and electrical properties are not affected.

[0030] In a typical automotive radar application, the free air wavelength λ 0 In the millimeter wave frequency range from 10 mm to 1 mm. In a specific variation in the frequency range of 55 GHz to 85 GHz, the free air wavelength λ 0 In the range of 5.5mm to 3.5mm. Free air wavelength λ 0 Typical values ​​for the periodicity in the range 5.5 mm to 3.5 mm are approximately λ 0 / 3. Alternatively or in addition, the protrusions may be arranged on the back side of the intermediate layer or antenna layer, thereby forming an AMC structure. These protrusions may be in the form of columns extending from the back side of the intermediate layer or antenna layer toward the front side of the printed circuit board and may be combined with the patch on the front side of the PCB.

[0031] At least one waveguide hole can be incorporated as a penetration in the conductive surface behind the front side of the antenna layer. The penetration can be established by a material ablation process, preferably by a laser process and / or a cutting process. After manufacturing the antenna layer, after previous metallization of the entire surface of the waveguide channel and / or the back side of the antenna layer, the waveguide holes required for radiation, for example designed as grooves and / or horns, can be realized in an etching process. In this case, the metallized surface will be removed by etching techniques. Alternatively, the waveguide holes required for radiation can be realized in a mechanical subtractive process, for example by engraving, scraping or milling, or by an ablation process, for example by a laser ablation process. By using the energy of a laser, the metal surface can be removed. Alternatively, the grooves can be realized by using a mask during the coating process.

[0032] In order to reduce the loss of signals within the material during transmission and / or reception of signals, if a directional radiation pattern is required, the thickness of the material between the radiation slot and the front face of the antenna layer is preferably kept less than twice the wavelength to avoid the propagation of electromagnetic waves in the material. For non-directional radiation patterns, a thicker layer of material between the front layer and the antenna hole is advantageous. If the antenna layer is too thick, part of the energy is unable to excite the material of the antenna layer and generate surface waves, which reduce the efficiency of the antenna and degrade the radiation pattern. In order to reduce losses, the antenna layer can be made by a foaming process. Compared with high-density materials, foams can reduce the dielectric constant without sacrificing thickness. The antenna layer can be made of foam material, made by an injection molding process, and include a sandwich structure and / or a honeycomb structure with a harder skin layer and a softer core. Foam injection molding is a manufacturing process that can be used to reduce the dielectric constant of the antenna layer and achieve the desired properties of radiation through the antenna layer. In view of the honeycomb core and thin skin, the dielectric constant of the material can be reduced compared to traditional injection molded parts.

[0033] Alternatively or in addition, in order to send and / or receive signals, at least one waveguide hole may be incorporated as a cavity into the back side of the antenna layer or behind the front side of the antenna layer. The cavity may be at least partially filled with a material that is transparent to electromagnetic waves. The cavity may be filled with a dielectric resonator, which is composed of a cube made of a material with a higher dielectric constant than the surrounding antenna layer (for example, the antenna cover material dk=2, the dielectric resonator dk=5.5). The dielectric resonator is configured to increase the antenna gain. The rotated dielectric resonator can be used to change the polarization of the radiation field. The antenna layer with the dielectric resonator can be realized by overmolding, 2K molding, while the outer layer and the dielectric resonator are made of one material and the core consists of a second material, or by foam injection molding, while the dielectric resonator is part of the skin layer.

[0034] Depending on the design, the electronic component may be arranged at the back side of the printed circuit board, communicatively connected to at least one waveguide channel via a feed hole extending across the printed circuit board from the back side to the front side. The electronic component (such as an MMIC) may be connected to the waveguide channel via at least one feed hole designed as a drilled hole in the PCB. The drilled hole is typically transparent to electromagnetic waves and may be plated and filled with material, or it may include ridges. Alternatively, the electronic component may be arranged at the front side of the printed circuit board, surrounded by a receiving space within the antenna layer in the assembled state and covered by an electromagnetic absorber in the form of a layer. In a variant, the MMIC component may be soldered on the top side of the PCB. In addition, an electromagnetic absorber may be placed on the chip to reduce any electromagnetic interference from the waveguide channel, or a heat sink structure may be placed for cooling the electronic component.

[0035] The front face of the antenna layer may be corrugated to further reduce the dielectric constant and implement a quarter-wavelength or broadband impedance transformation for waves radiated from the waveguide aperture through the front surface. The corrugations allow the removal of material from the antenna layer that can be replaced by air, thereby reducing the overall dielectric constant of the antenna device. The waves radiated from the waveguide aperture propagate in a material with a lower dielectric constant. Therefore, they experience less distortion, and the structure can achieve a more uniform radiation distribution. The front face of the antenna layer may be designed as a corrugated surface including an array of notches for reducing the overall dielectric constant.

[0036] Alternatively or in addition, a scattering surface may be arranged at the back side of the antenna layer, adjacent to at least one waveguide channel, consisting of protrusions and / or grooves arranged in columns, and / or arranged at the front side of the printed circuit board, comprising an array of planar metal structures in the form of patches. The scattering surface may be implemented in the antenna layer in the form of an array of cavities close to the waveguide channels in order to reduce reflections between the front side of the antenna layer and the back side of the antenna layer or additional components arranged in front of the antenna device (e.g. a bumper of a car, etc.). The protrusions and / or grooves of a first column are typically displaced relative to the protrusions and / or grooves of an adjacent column by a length substantially equal to the wavelength. Alternatively, the antenna layer may be made as an integral part of a body part, such as a bumper, a windshield, a headlight, etc. Good results may be achieved when the antenna layer, as the front layer of the antenna device, is made integrally with the body part (e.g. by injection molding). This has the advantage that the printed circuit board and the back part / housing of the antenna device can be mounted more easily, requiring fewer parts.

[0037] Typically, a PCB consists of several inner layers (multilayer PCB), at least two of which are conductive materials. The top layer of the PCB consists of a metal material and a waveguide channel is formed there together with the antenna layer.

[0038] The antenna layer may be attached to the first metal layer of the PCB. Alternatively, the antenna layer may be attached to a different conductive layer than the multi-layer PCB, without the need for mechanical connection to the top metal layer.

[0039] Alternatively, the antenna layer may be connected to the housing and all other parts described herein.

[0040] In order to seal the PCB and the electronic components from environmental influences, the back side of the antenna layer can be welded to the housing. As an alternative to welding or in addition to welding, the antenna layer can also be attached to the housing by gluing or soldering. The back side of the antenna layer is typically welded to the wall of the housing in a circumferential manner. Alternatively or in addition, the antenna layer may include a pin which protrudes from the back side of the antenna layer and engages with a recess in the PCB in the installed state. The pin can be configured to align the antenna layer relative to the PCB. The PCB can be clamped between the antenna layer and the housing in the installed state.

[0041] Alternatively or in addition, the antenna layer may include a pin including a collar that, in the installed state, forms an undercut with the printed circuit board to secure the PCB relative to the antenna layer. The collar may be formed by plastic forming or thermoforming of the pin. The PCB may be held in place by the collar clamping the PCB to the antenna layer and thereby holding it in position relative to the housing. Alternatively, the antenna layer may include a pin including a thread. In the installed state, the antenna layer may be secured in position relative to the housing by a nut that is threadedly connected to the pin from the back of the housing.

[0042] Alternatively, the antenna layer may comprise a pin comprising a snap-on finger. In the mounted state, the antenna layer may be fixed in position relative to the housing by a snap-on finger, which engages with a recess in the back side of the housing. Alternatively, the antenna layer may be fixed in position relative to the housing by a rivet, in addition to a pin with a collar or a pin with a thread. By means of the rivet, the PCB may be clamped between the antenna layer and the housing. Alternatively, the pin for aligning the PCB relative to the antenna layer may be designed as a press-fit pin, which engages with the PCB in the mounted state. As an alternative to a threaded connection solution or a pin, the antenna layer may be mounted to the housing by means of a bayonet lock. The male pin of the bayonet lock may be arranged at the antenna layer and aligned with a slot in the housing in the mounted state by pushing the antenna layer and the housing together.

[0043] It will be understood that both the foregoing general description and the following detailed description present embodiments and are intended to provide an overview or framework for understanding the nature and character of the present disclosure. The accompanying drawings are included to provide a further understanding and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate various embodiments and, together with the description, serve to explain the principles and operation of the disclosed concepts. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The disclosure described herein will be more fully understood from the detailed description given below and the accompanying drawings, which should not be considered as limiting the disclosure described in the appended claims. These drawings show: Figure 1 A first variant of the antenna device is shown in a perspective exploded view from behind and above; Figure 2 Show according to Figure 1 an enlarged detailed view of an antenna layer of an antenna device; Figure 3 Show according to Figure 1 A perspective exploded view of the antenna device viewed from the front and from above; FIG. 4 shows that according to Figure 1 Front view of the antenna device ( Figure 4a ) and cross-sectional view ( Figure 4b ); Figure 5 A second variant of the antenna device is shown in a perspective side view, wherein the antenna layer is unfolded; Figure 6 A third variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Figure 7 A fourth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Figure 8 A fifth variant of the antenna device is shown in a perspective side view, wherein the antenna layers are unfolded; Fig. 9 A sixth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Fig.10 A seventh variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Fig.11 An eighth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Fig.12 A ninth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded; Fig.13 A tenth variant of the antenna device is shown in a perspective side view, wherein the antenna layers are unfolded; Fig.14 An eleventh variant of the antenna arrangement is shown in a perspective exploded view from the front and above; Fig.15 A twelfth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded and exploded; FIG. 16 is a top perspective view ( Fig.16a ) and cross-sectional view (16b) show a twelfth variation of the antenna device; Fig.17 A thirteenth variation of the antenna device is shown in a perspective side view, with the antenna layers unfolded and exploded; FIG. 18 is a top perspective view ( Fig.18a ) and cross-sectional view (18b) show a thirteenth variation of the antenna device; Fig.19 A fourteenth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded and exploded; FIG. 20 is a top perspective view ( Fig.20a ) and cross-sectional view (20b) show a fourteenth variation of the antenna device; Fig.21 A fifteenth variant of the antenna device is shown in a perspective side view, with the antenna layers unfolded and exploded; FIG. 22 is a top perspective view ( Fig.22a ) and cross-sectional view (22b) show a fifteenth variation of the antenna device; Fig.23 shows a line-symmetric periodic pattern of patches forming an AMC structure on the front surface of a PCB; Fig.24 A sliding symmetric periodic pattern of patches forming an AMC structure on the front surface of a PCB is shown; Fig.25 showing a pseudo-periodic or random pattern of patches forming an AMC structure on the front surface of a PCB; Fig.26 A variation of the antenna device is shown, wherein a first variation of the connecting element is in an unfolded state; Fig. 27 Show according to Fig.26 A variation of the antenna device, wherein hidden edges are shown; FIG. 28 shows the Fig.26 A variation of the antenna arrangement, wherein Fig.28a A cross-sectional view is shown in FIG. Fig.28b An enlarged view thereof is shown in FIG. Fig.29 shows a variant of the antenna device, in which a second variant of the connecting element with a hidden edge is shown; FIG. 30 shows the Fig.29 A variation of the antenna arrangement, wherein Fig.30a A cross-sectional view is shown in FIG. Fig.30b An enlarged view thereof is shown in FIG. Fig.31 shows variations of the antenna arrangement, wherein a third variation of the connecting element with a hidden edge is shown; FIG. 32 shows the Fig.31 A variation of the antenna arrangement, wherein Fig.32a A cross-sectional view is shown in FIG. Figure 32b An enlarged view thereof is shown in FIG. Fig.33 shows variations of the antenna arrangement, wherein a fourth variation of the connecting element with a hidden edge is shown; FIG. 34 shows that according to Fig.33 A variation of the antenna arrangement, wherein Fig.34a A cross-sectional view is shown in FIG. Fig.34b An enlarged view thereof is shown in FIG. Fig.35 shows variations of the antenna arrangement, wherein a fifth variation of the connecting element with a hidden edge is shown; FIG. 36 shows the Fig.35 A variation of the antenna arrangement, wherein Fig.36a A cross-sectional view is shown in FIG. Fig.36b An enlarged view thereof is shown in FIG. Fig.37 shows variations of the antenna arrangement, wherein a sixth variation of the connecting element with a hidden edge is shown; FIG. 38 shows the Fig.37 A variation of the antenna arrangement, wherein Fig.38a A cross-sectional view is shown in FIG. Figure 38b An enlarged view thereof is shown in FIG. Fig.39 shows variations of the antenna device, wherein a seventh variation of the connecting element with a hidden edge is shown; FIG. 40 shows the Fig.39 A variation of the antenna arrangement, wherein Fig.40aA cross-sectional view is shown in FIG. Fig.40b An enlarged view thereof is shown in FIG. Fig.41 shows variations of the antenna device, wherein an eighth variation of the connecting element with a hidden edge is shown; FIG. 42 shows the Fig.41 A variation of the antenna arrangement, wherein Fig.42a A cross-sectional view is shown in FIG. Figure 42b An enlarged view thereof is shown in FIG. Fig.43 shows variations of the antenna device, wherein a ninth variation of the connecting element with a hidden edge is shown; FIG. 44 shows the Fig.43 A variation of the antenna arrangement, wherein Fig.44a A cross-sectional view is shown in FIG. Figure 44b An enlarged view thereof is shown in FIG. Fig.45 A variation of an antenna device with an embedded chip (MMIC) is shown, wherein the antenna layer is unfolded; Figure 46 Fig.46a The cross-sectional view and Fig.46b The enlarged view in FIG. 1 shows Fig.45 A variation of the antenna arrangement; Fig.47 shows a variation of an antenna device with an embedded chip (MMIC) and a PCB waveguide, wherein the antenna layer is unfolded; Figure 48 Fig.48a The cross-sectional view and Fig.48b The enlarged view in FIG. 1 shows Fig.47 A variation of the antenna arrangement. DETAILED DESCRIPTION

[0045] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all, features are shown. Indeed, the embodiments disclosed herein may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, like reference numerals will be used to refer to like components or parts.

[0046] Figure 1 FIG. 4 shows a first variant of the antenna device 1 . Figure 1 The first variant is shown in a perspective exploded view from the back and from above. Figure 2 An enlarged detailed view of the antenna layer 6 of a first variant of the antenna device 1 is shown. Figure 3 Shown in perspective exploded view from the front and above. Figure 4a shows a front view of the antenna device, Figure 4bA cross-sectional view is shown. The antenna device 1 shown for automotive radar applications comprises a printed circuit board (PCB) 2 having a front side 3 and a back side 4 and an electronic component 5 interconnected to the printed circuit board 2. In the variant shown, an electronic component 5 in the form of a monolithic microwave integrated circuit (MMIC) is used, which comprises a plurality of circuits integrated into a small package for operation at microwave frequencies. In the variant shown, the MMIC is arranged directly on the front side 3 of the printed circuit board 2. In order to guide the signal from the electronic component 5 to at least one waveguide hole 9 configured for sending and / or receiving signals, the antenna device 1 comprises an antenna layer 6 having a front side 7 and a back side 8, which is interconnected to the front side 3 of the printed circuit board 2. In the variant shown, the antenna layer 6 is further configured to serve as a radome, thereby protecting the antenna device 1 from environmental influences. Therefore, the antenna layer 6 is typically made of a material that resists environmental influences, such as a material that does not absorb moisture. The antenna layer 6 shown may be at least partially made of a metallic material and / or include a metallization layer forming a conductive surface. In case the antenna layer 6 is made by injection moulding of at least one plastic material, the rear side 8 and / or the recess 12 are typically metallised with an electrically conductive material.

[0047] If available from Figure 2 and Figure 3 Optimally obtained, for receiving or transmitting signals, the waveguide aperture 9 shown is interconnected to the front side 7 of the antenna layer 6 and is communicatively connected to the electronic component via at least one waveguide channel 10. In a variant, the at least one waveguide channel 10 is designed as a substantially rectangular waveguide channel 10, which can be considered as a tube typically consisting of four walls. The waveguide channel 10 shown is formed by a recess 12 arranged between the back side 8 of the antenna layer 6 and the front side 3 of the printed circuit board 2. In order to be able to guide electromagnetic signals, the at least one waveguide channel 10 typically comprises a conductive surface 11 for guiding electromagnetic fields between the electronic component and the at least one waveguide aperture 9. The waveguide channel 10 shown is formed by placing the edge of the recess 12 in direct contact with the metallized front side 3 of the PCB 2 or a conductive intermediate layer between the back side 8 of the antenna layer 6 and the front side 3 of the PCB 2. The waveguide aperture 9 shown is incorporated behind the front side 7 of the antenna layer 6 as a penetration 17 in the conductive surface 11. Good results with regard to manufacturability can be achieved, as shown in the present variant, when the recess 12 is at least partially formed by a deepening 13 in the back side 8 of the antenna layer 6. This is particularly advantageous for injection molding or die casting, since the part can be easily demoulded.

[0048] 4 shows a variant with an antenna layer 6, wherein a waveguide channel 10 extends within the antenna layer 6. The waveguide hole 9 shown is incorporated as a cavity 16 in the back side 8 of the antenna layer 6. The cavity shown in the back side 8 of the antenna layer 6 can be at least partially filled with a material transparent to electromagnetic fields for protecting at least the waveguide channel 10 and the interior of the antenna device 1 from environmental influences. The cavity 16 can be filled with a dielectric resonator 29, which consists of a cube made of a material with a higher dielectric constant than the surrounding antenna layer 6 (e.g. radome material dk=2, dielectric resonator dk=5.5).

[0049] Figure 5 A second variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded. Electronic components, not shown, are arranged at the back side of the printed circuit board 2 and are communicatively connected to at least one waveguide channel 10 via feed holes 18, which extend across the printed circuit board 2 from the back side to the front side 3. Electronic components, not shown, in the form of MMIC components, are coupled to the waveguide channels 10 via the shown feed holes 18, which are designed as drilled holes through the PCB 2. These drilled holes are typically transparent to electromagnetic waves and can be plated and filled with material or not plated and filled with material.

[0050] Figure 6 A third variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded. The electronic component 5 shown is arranged at the front side 3 of the printed circuit board 2, surrounded by a receiving space 19 in the antenna layer 6 in the assembled state, and covered by an electromagnetic absorber in the form of a layer 20. The feeding hole 18 shown is arranged in the back side 8 of the antenna layer 6 and merges laterally from the receiving space 19 into several waveguide channels 10. The signal is fed from the electronic component 5 into the waveguide channel 10 via a planar transition line 35. The electromagnetic absorber 20 shown in the form of a layer is placed on the electronic component 5 to reduce any electromagnetic interference from the waveguide channel 10.

[0051] Figure 7 A fourth variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded. The variant shown comprises a scattering surface 26 arranged at the back side 8 of the antenna layer 6 adjacent to at least one waveguide channel 10, the at least one scattering surface 26 consisting of protrusions 27 arranged in columns and / or recesses in the form of grooves. The scattering surface 26 shown is implemented in the antenna layer 6 in the form of an array of protrusions 27 close to the waveguide channel 10 in order to reduce reflections between the front side 7 of the antenna layer 6 and the back side 8 of the antenna layer 6 or additional components arranged in front of the antenna device 1 (e.g. a bumper of a car, etc.). The protrusions 27 and / or grooves (not shown) of a first column are typically displaced relative to the protrusions 27 and / or grooves of an adjacent column by a length substantially equal to the wavelength. Figure 8A fifth variant of the antenna device 1 is shown in a perspective side view with the antenna layer 6 unfolded. In the variant shown, the scattering surface 26 is implemented on the front side 3 of the PCB 2 in the form of an array of metallic planar patches 28 (eg square patches close to the feed holes 18).

[0052] Figures 9 to 13 Sixth to tenth variants are shown, in which the waveguide channel 10 is partially formed by an electromagnetic bandgap structure (EBG). The recess 12 of the variant shown is formed by a protrusion 14, which forms an electromagnetic bandgap structure (EBG) and extends over the back side 8 of the antenna layer 6 and / or the front side 3 of the printed circuit board 2. The protrusion 14 shown forms the recess 12 by laterally delimiting the waveguide channel 10. The protrusion 14 can be made integrally with the antenna layer 6, or arranged at the front side 3 of the printed circuit board 2 in the form of a plurality of metallized patches 28 arranged on the front side 3 of the PCB 2.

[0053] Fig. 9 A sixth variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded. In the variant shown, the waveguide channel 10 is designed as a deepening 13 arranged in the back side 8 of the antenna layer 6 and a patch 34 arranged on the front side 3 of the PCB 2 surrounding the recess 12. The patch 34 on the front side 3 of the PCB 2 shown is a metasurface to avoid leakage. Fig.10 A seventh variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded. The signal is fed from the MMIC electronics (not shown) into a waveguide channel 10, which in turn feeds a planar antenna, for example a patch antenna or a SIW slot antenna integrated on the front side 3 of the PCB 2 as shown. Fig.11 An eighth variant of the antenna device 1 is shown in a perspective side view, in which the antenna layer 6 is unfolded and the waveguide channel 10 is formed by the projection 14 .

[0054] Fig.12 A ninth variant of the antenna device 1 is shown in a perspective side view, wherein the antenna layer 6 is unfolded. The antenna layer may include a ridge 33, which is arranged in the recess 12 and extends substantially along the waveguide channel 10. The ridge 33 may extend substantially from the feed hole 18 to the at least one waveguide hole 9. The ridge 33 may be arranged in the recess 12 of the waveguide channel 10 for reducing the overall size of the waveguide channel 10. Fig.13 A tenth variant of the antenna device 1 is shown in a perspective side view, wherein the antenna layer 6 is unfolded. The waveguide channel 10 shown comprises a coaxial waveguide by comprising a metal strip serving as an inner conductor 21 in the center of the waveguide channel. The inner conductor 21 enables the size of the waveguide channel 10 to be further reduced.

[0055] Fig.14An eleventh variant of the antenna device 1 is shown in a perspective exploded view from the front and above, having a corrugated front face. The front face 7 of the antenna layer 6 shown is corrugated 24 to further reduce the dielectric constant and implement a quarter-wavelength impedance transformation for the waves radiated from the waveguide hole through the front surface 7. The corrugations 24 allow the removal of material that can be replaced by air from the antenna layer 6, thereby reducing the overall dielectric constant of the antenna device 1. The waves radiated from the waveguide hole 9 propagate in a material with a lower dielectric constant. Therefore, they experience less distortion and the structure can achieve a more uniform radiation distribution. The front face 7 of the antenna layer 6 shown is designed as a corrugated surface 24 including an array of notches 25 for reducing the overall dielectric constant.

[0056] Fig.15 16 shows a twelfth variation of the antenna device 1. The antenna device 1 shown includes a printed circuit board (PCB) 2 having a front side 3 and a back side 4 and an electronic component 5 arranged on the back side 4 of the PCB 2. The waveguide hole 9 is interconnected to the front side 7 of the antenna layer 6 and is communicatively connected to the electronic component 5 through a waveguide channel 10. The waveguide channel 10 shown is formed by a recess 12, which is partially arranged in the back side 8 of the antenna layer 6 and the front side 3 of the PCB 2. A plurality of metal patches 34 are arranged on the front side 3 of the PCB 2 to form an AMC structure. The metal patches 34 are arranged on the front side 3 of the PCB 2 in a symmetrical pattern with periodic intervals. This design utilizes the basic concept of a half-mode waveguide to halve the height of the waveguide channel. In order to be able to halve the height, the electric field of the signal is mirrored by a planar metal structure 28. The electromagnetic field is fed into the waveguide channel 10 via a feeding hole 18 arranged in the PCB 2. In addition, the antenna layer 6 comprises a scattering surface 26 arranged at the back side 8 of the antenna layer 6 adjacent to the waveguide channel 10. The scattering surface 26 shown is implemented in the back side 8 of the antenna layer 6 in the form of an array of cavities close to the waveguide channel 10 in order to reduce reflections between the front side 7 of the antenna layer 6 and the back side 8 of the antenna layer 6 or additional components arranged in front of the antenna device 1 (e.g. a bumper of a car, etc.). The antenna layer 6 shown is configured to serve as a radome, which protects at least the front side 3 of the printed circuit board 2 from environmental influences.

[0057] Fig.1718 shows a thirteenth variation of the antenna device 1. The antenna device 1 shown comprises a printed circuit board (PCB) 2 having a front side 3 and a back side 4 and an electronic component 5 arranged on the back side 4 of the PCB 2. An intermediate layer 36 is arranged between the front side 4 of the PCB 2 and the back side 8 of the antenna layer 6. The front side 37 of the intermediate layer 36 faces the back side 8 of the antenna layer 6. The back side 38 of the intermediate layer 36 faces the front side 3 of the PCB 2. The waveguide hole 9 is interconnected to the front side 7 of the antenna layer 6 and is communicatively connected to the electronic component 5 through a waveguide channel 10, which is arranged in the intermediate layer 36 and extends from the back side 38 to the front side 37. The waveguide channel 10 comprises a conductive surface 11 for guiding an electromagnetic field between the electronic component 5 and the waveguide hole 9. The electromagnetic field is fed into the waveguide channel 10 via a feeding hole arranged in the PCB 2. The shown antenna layer 6 comprises scattering surfaces 26 in the back side 8 in the form of an array of cavities close to the waveguide channels 10 in order to reduce reflections between the front side 7 of the antenna layer 6 and the back side 8 of the antenna layer 6 or additional components.

[0058] Fig.19 20 shows a fourteenth variation of the antenna device 1. The antenna device 1 shown includes a printed circuit board (PCB) 2 having a front side 3 and a back side 4 and an electronic component 5 arranged on the back side 4 of the PCB 2. An intermediate layer 36 is arranged between the front side 3 of the PCB 2 and the back side 8 of the antenna layer 6. The front side 37 of the intermediate layer 36 faces the back side 8 of the antenna layer 6. The antenna layer 6 of the variation shown is made by insert molding. A metal insert 39 is loaded into the mold and then overmolded by molten plastic injected into the mold to form the antenna layer 6. In the variation shown, a scattering surface 26 is implemented in the back side of the metal insert 39 of the antenna layer 6 in the form of an array of cavities close to the waveguide channel 10 so as to reduce reflections between the back side 8 and the front side 7 of the antenna layer 6. The back layer 40 and the front layer 39 are connected along a parting plane 41. The waveguide holes 9 are interconnected to the front side 7 of the antenna layer 6 and are communicatively connected to the electronic component 5 via a waveguide channel 10 arranged in the intermediate layer 36 extending from the back side 38 to the front side 37. The waveguide channel 10 comprises a conductive surface 11 for guiding an electromagnetic field between the electronic component 5 and the waveguide holes 9.

[0059] Fig.2122 shows a fifteenth variation of the antenna device 1. The antenna device 1 shown includes a printed circuit board (PCB) 2 having a front side 3 and a back side 4 and an electronic component 5 arranged on the back side 4 of the PCB 2. An intermediate layer 36 is arranged between the front side 3 of the PCB 2 and the back side 8 of the antenna layer 6. In the variation shown, the intermediate layer 36 includes a protrusion 14 arranged on the front side 37 of the intermediate layer. The antenna layer 6 of the variation shown is made by insert molding. A metal insert 39 is loaded into the mold and then overmolded by molten plastic injected into the mold to form the antenna layer 6. In the variation shown, a scattering surface 26 is implemented in the back side of the metal insert 39 of the antenna layer 6 in the form of an array of cavities close to the waveguide channel 10 so as to reduce or eliminate reflections between the back side 8 and the front side 7 of the antenna layer 6. The waveguide holes 9 are interconnected to the front side 7 of the antenna layer 6 and are communicatively connected to the electronic component 5 through a waveguide channel 10, which is partially arranged in the intermediate layer 36 and extends from the back side 38 to the front side 37. The waveguide channel 10 includes a conductive surface 11 for guiding the electromagnetic field between the electronic component 5 and the waveguide holes 9. The electromagnetic field is fed into the waveguide channel 10 via a feeding hole 18 arranged in the PCB 2. The design utilizes the basic concept of a half-mode waveguide to reduce the height of the waveguide channel by half.

[0060] Fig.23 A schematic line-symmetric periodic pattern of metal patches 34 forming an AMC structure on the front surface of the PCB 2 is shown. The substantially square metal patches 34 are arranged line-symmetric relative to each other at equal intervals in the x and y directions. The lateral distances (periodicity) between the patches relative to each other are typically selected with respect to the emission wavelength. The size of the patches is related to the guided wavelength. The wavelength can be calculated as follows: λ 0 = free air wavelength ε r PCB = Dielectric constant of PCB substrate

[0061] Periodicity is usually in λ 0 / 8-2λ 0 The patches are typically arranged in a collinear array, where the array forms rows and columns. Between adjacent columns, the patches are arranged with a first periodicity P x spaced apart, and between adjacent rows there is a second periodicity P y Spaced apart.

[0062] Fig.24 FIG. 2 shows a sliding symmetric periodic pattern of metal patches 34 forming an AMC structure on the front surface of PCB 2. Fig.23Compared to the variant shown in , the patches within one array are again spaced apart by a distance equal to the periodicity. Adjacent arrays are offset relative to each other by a distance equal to P / n, where n is a natural number.

[0063] Fig.25 A pseudo-periodic or random pattern of patches forming an AMC structure on the front surface of a PCB is shown. The substantially circular metal patches 34 are arranged asymmetrically relative to each other at random intervals in the x and y directions. The lateral distances (periodicity) between the patches relative to each other are typically selected as follows: N = number of patches d n = Distance between patches

[0064] Figure 26 to Figure 2 8 shows a variant of the antenna device 1 with a first variant of the connecting element 31. The antenna device 1 shown comprises a printed circuit board (PCB) 2 and electronic components interconnected to the printed circuit board 2. The antenna layer 6 shown has a front side 7 and a back side 8, which is interconnected to the front side 3 of the printed circuit board 2. In the variant shown, the antenna layer 6 is additionally configured to serve as a radome, thereby protecting the antenna device 1 from environmental influences. As can be seen from Fig. 27 Optimally, in order to seal the PCB 2 and the electronic components from environmental influences, the back side 8 of the antenna layer 6 is welded to the housing 40. As an alternative to welding or in addition to welding, the antenna layer 6 can also be attached to the housing 40 by gluing or soldering. In the variant shown, the back side 8 of the antenna layer 6 is welded to the wall of the housing 40 in a circumferential manner. As can be best seen from FIG. 28 , the antenna layer 6 is attached to the housing 40 via welding in the mounted state. The antenna layer 6 shown comprises a pin 41 which protrudes from the back side 8 of the antenna layer 6 and which engages with a recess 42 in the PCB 2 in the mounted state. The two pins 41 shown are configured to align the antenna layer 6 with the PCB 2. The PCB 2 is clamped between the antenna layer 6 and the housing 40 in the mounted state.

[0065] Fig.29 30 shows a variant of the antenna device 1 with a second variant of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.29As best seen, the antenna layer 6 shown is also attached to the housing 40 via welding in the mounted state, in the variant shown via ultrasonic welding. The antenna layer 6 also includes a pin 41 configured to align the antenna layer 6 with the PCB 2. In addition, as best seen from FIG. 30 , the antenna layer 6 includes a pin 41 that includes a collar 43. In the mounted state, the collar 43 forms an undercut with the printed circuit board 2 to fix the PCB 2 relative to the antenna layer 6. The collar 43 is formed by plastic forming or thermoforming of the pin 41. The PCB 2 is held in place by the collar 43 clamping the PCB 2 to the antenna layer 6 and thereby holding it in place relative to the housing 40.

[0066] Fig.31 32 shows a variant of the antenna device 1 with a third variant of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.31 The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 41, similar to the one provided by Figure 26 to Figure 2 8. In addition, as can be best seen from FIG. 32, the antenna layer 6 comprises a pin, which comprises a thread 44. In the mounted state, the antenna layer 6 is fixed in position relative to the housing 40 by a nut 45, which is threaded onto the pin 41 from the back of the housing 40. The PCB 2 is thereby clamped between the antenna layer 6 and the housing 40.

[0067] Fig.33 34 shows a variant of the antenna device 1 with a fourth variant of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.33 The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 41, similar to the one provided by Figure 26 to Figure 2 8. In addition, as can be best seen from FIG34, the antenna layer 6 includes a pin including a snap-fit ​​finger 46. In the mounted state, the antenna layer 6 is fixed in position relative to the housing 40 by the snap-fit ​​finger 46, which engages with a recess 42 in the back of the housing 40. By means of the snap-fit ​​joint, the PCB 2 is clamped between the antenna layer 6 and the housing 40.

[0068] Fig.35 36 shows a modification of the antenna device 1 with a fifth modification of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.35The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 41, similar to the one provided by Figure 26 to Figure 2 8. In addition, as can be best seen from Figure 36, the antenna layer 6 is fixed in position relative to the housing 40 by rivets 47. By means of the rivets 47, the PCB 2 is clamped between the antenna layer 6 and the housing 40.

[0069] Fig.37 38 shows a modification of the antenna device 1 with a sixth modification of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.37 The antenna layer 6 shown is welded, glued or soldered to the housing 40 as best obtained. The antenna layer also includes press-fit pins 48, as can be best seen from FIG. 38. The antenna layer 6 includes pins 41 for aligning the PCB 2 relative to the antenna layer 6 by engaging with recesses 42 in the PCB 2, and the press-fit pins 48 engage with the PCB 2 in the mounted state. The PCB 2 is thereby clamped to the antenna layer 6, and the antenna layer 6 is fixed relative to the housing 40.

[0070] Fig.39 40 shows a modification of the antenna device 1 with a seventh modification of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.39 The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 40, similar to that of the housing 40. Figure 26 to Figure 2 8. In addition, as can be best seen from FIG. 40, the antenna layer 6 comprises pins 41 which, in the mounted state, engage with holes 49 in the housing 40 and which are hot stamped for fixing the antenna layer 6 relative to the housing 40. The PCB 2 is thereby clamped between the antenna layer 6 and the housing 40.

[0071] Fig.41 42 shows a modification of the antenna device 1 having an eighth modification of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.41 The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 41, similar to the one provided by Figure 26 to Figure 28. In addition, as can be best seen from FIG. 42, the antenna layer 6 is screwed to the housing 40 from the back side of the housing 40. The screw head is thus in a mounted position, arranged in a recess 50 in the back side of the housing 40. The PCB 2 is clamped between the antenna layer 6 and the housing 40.

[0072] Fig.43 44 shows a modification of the antenna device 1 with a ninth modification of the connecting element 31. The antenna device 1 shown comprises Figure 26 to Figure 2 8. Fig.43 The antenna layer 6 shown is also attached to the housing 40 in the mounted state via a connecting element 31, which includes a pin 41, similar to the one provided by Figure 26 to Figure 2 8. In addition, as can be best seen from Figure 44, the antenna layer 6 is mounted to the housing 40 by means of a bayonet lock 51. By pushing the antenna layer and the housing together, the male pins 52 arranged at the antenna layer align with the slots 53 in the housing in the mounted state.

[0073] Fig.45 46 shows a variant of an antenna device 1 with an embedded electronic component 5. The electronic component 5 shown is a chip (MMIC), typically a radar chip, which typically includes a plurality of circuits integrated into a small package for operation at microwave frequencies. The chip is embedded in a printed circuit board 2. In the variant shown, the chip is embedded in one of the layers of substrate material. Such substrate material typically consists of printed circuit board material or any other material suitable for embedding a chip (silicon, ceramic, glass, molding compound). The electromagnetic signal is fed from the integrated MMIC to the waveguide channel 10 inside the antenna layer 6 via a planar transition line 35.

[0074] Fig.47 48 shows a variation of the antenna device 1 with an embedded chip (MMIC) and a PCB waveguide. Fig.45 46, the electronic component 5 is also embedded in one of the layers of the printed circuit board 2 by embedding in the substrate material. Fig.45 46, the electromagnetic signal is fed from the electronic component 5 to the waveguide channel 10 inside the antenna layer 6 through a three-dimensional transition line 54. The three-dimensional transition line 54 is in the form of a substrate integrated waveguide (SIW), a dielectric loaded embedded waveguide and / or an air filled embedded waveguide.

[0075] Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.

[0076] Name List 1 Antenna device 2Printed Circuit Board (PCB) 3. Front side (PCB) 4Back side (PCB) 5 Electronic components 6 Antenna Layer 7 Front 8 Back 9 Waveguide hole 10 waveguide channels 11 Conductive surface 12 recesses 13 Deepening 14 protrusion 15 metallization layers 16 Cavity 17 penetration 18 Feeding holes 19 Receiving Space 20Electromagnetic absorber 21 Inner conductor 22 Cortex 23 cores 24 Corrugated surface 25 notches 26 Scattering Surface 27 Protrusion 28 plane metal structure 29 Dielectric Resonator 30 back layer / shell 31 Connecting elements 32 Drilling 33 Ridge 34 patches 35 plane transition line 36 Middle Layer 37 Positive 38 Back 39 insert (antenna layer) 40 Shell 41 pins 42 recess (PCB) 43 shaft collar (pin) 44 thread 45 Nut 46 snap finger 47 rivets 48 Press-fit pin 49 Drilling 50 recesses 51 bayonet lock 52 pins (bayonet lock) 53 slots (bayonet lock) 54 three-dimensional transition lines.

Claims

1. An antenna device (1) for automotive radar applications, comprising: a. a printed circuit board (2) having a front side (3) and a back side (4) and electronic components (5) interconnected to the printed circuit board (2), b. an antenna layer (6), the antenna layer (6) having a front side (7) and a back side (8), the back side (8) being interconnected to the front side (7) of the printed circuit board (2), wherein i. at least one waveguide hole (9) interconnected to the front side (7) of the antenna layer (6) and communicatively connected to the electronic component (5) through at least one waveguide channel (10), wherein ii. The at least one waveguide channel (10) comprises a conductive surface (11) for guiding electromagnetic fields between the electronic components (5) and is formed by a recess (12) arranged between the back side (8) of the antenna layer (6) and the front side (3) of the printed circuit board (2).

2. The antenna device (1) according to claim 1, wherein: The front side (7) of the antenna layer (6) is designed to serve as a radome, which protects at least the front side (3) of the printed circuit board (2) from environmental influences.

3. The antenna device (1) according to claim 1 or 2, wherein: The recess (12) is at least partially formed by a deepening (13) in the back side (8) of the antenna layer (6) and / or a protrusion (14) extending above the back side (8) of the antenna layer (6) and / or a planar metal structure (28) on the front side (3) of the printed circuit board (2).

4. The antenna device (1) according to claim 3, wherein: The protrusion (14) laterally delimits the recess (12) and forms an electromagnetic bandgap structure with the front side (3) of the printed circuit board (2).

5. The antenna device (1) according to claim 3 or 4, wherein: The planar metal structure (28) comprises a plurality of patches (34) which laterally delimit the recess (12) and form an electromagnetic bandgap structure with the protrusion (14) or the back side (8) of the antenna layer (6).

6. The antenna device (1) according to any one of the preceding claims, wherein: The front side (3) of the printed circuit board (2) is at least partially covered by a plurality of metal patches (34), which are arranged in a periodic structure and form an artificial magnetic conductor (AMC).

7. The antenna device (1) according to at least one of the preceding claims, wherein: The antenna layer (6) is at least partially made of a metallic material and / or comprises a metallization layer (15) forming a conductive surface.

8. The antenna device (1) according to at least one of the preceding claims, wherein: At least one waveguide hole (9) is incorporated as a penetration (17) in the conductive surface behind the front side (7) of the antenna layer (6).

9. The antenna device (1) according to claim 8, wherein: The penetration (17) is produced by a material ablation process step, preferably by a laser process and / or a cutting process.

10. The antenna device (1) according to at least one of the preceding claims, wherein: At least one waveguide hole (9) is incorporated as a cavity (16) in the back side (8) of the antenna layer (6), the cavity (16) being at least partially filled with a material transparent to electromagnetic waves.

11. The antenna device (1) according to at least one of the preceding claims, wherein: The electronic component (5) is arranged at the back side (4) of the printed circuit board (2) and is communicatively connected to the at least one waveguide channel (10) via a feed hole (18), which extends across the printed circuit board (2) from the back side (4) to the front side (3).

12. The antenna device (1) according to any one of claims 1 to 10, wherein: The electronic component (5) is arranged on the front side (3) of the printed circuit board (2) and is surrounded by a receiving space (19) in the antenna layer (6) in the assembled state.

13. The antenna device (1) according to claim 12, wherein: A feed hole (18) is arranged in the back side (8) of the antenna layer (6) and merges into a waveguide channel (10), and the waveguide channel (10) merges into the waveguide hole (9) arranged at the front side (7) of the antenna layer (6).

14. The antenna device (1) according to at least one of the preceding claims, wherein: The antenna layer (6) comprises a ridge (33) which is arranged within the recess (12) and extends substantially along the waveguide channel (10).

15. The antenna device (1) according to at least one of the preceding claims, wherein: The antenna layer (6) is made of foamed material and is manufactured by an injection molding process.

16. The antenna device (1) according to at least one of the preceding claims, wherein: The front side (7) of the antenna layer (6) is designed as a corrugated surface (24) comprising an array of notches (25) for reducing the overall dielectric constant.

17. The antenna device (1) according to at least one of the preceding claims, wherein: Scattering surface (26) arrangement: a. at the back side (8) of the antenna layer (6), adjacent to the at least one waveguide channel (10), consisting of protrusions (27) and / or grooves arranged in rows, and / or b. An array of planar metal structures (28) at the front side (3) of the printed circuit board (2).

18. The antenna device (1) according to claim 17, wherein: The projections (27) and / or grooves of a first column are displaced relative to the projections (27) and / or grooves of an adjacent column by a length substantially equal to a multiple of half a wavelength.

19. The antenna device (1) according to at least one of the preceding claims, wherein: The antenna layer (6) is manufactured as an integral component of the vehicle body part.

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