ANTENNA MODULE FOR A MOTOR VEHICLE

Description

[0001] The invention relates to an antenna module for a motor vehicle, wherein the antenna module comprises at least one AM antenna, FM antenna and DAB antenna.

[0002] US 2021 / 057805 A1, KR 2017 0003986 U, KR 20190091688 A, US 2018269567 A1 and US 2020028249 A1 disclose antenna modules.

[0003] The connectivity of vehicles is constantly increasing. While vehicle antennas were previously primarily intended for radio reception, today additional antennas must be integrated. These additional antennas include, for example, Wi-Fi antennas, V2X antennas, antennas for providing mobile or internet connectivity (which can also be used as eCall antennas), or antennas for providing location services, such as a GNSS antenna. For radio reception, multiple antennas are particularly advantageous, for example, an AM antenna, an FM antenna, and a DAB antenna. Ideally, as many antennas as possible should be integrated into a single module in the smallest possible space.However, the problem is that antennas themselves must be sufficiently large to ensure adequate reception within their assigned frequency range. Furthermore, depending on the transmit and receive frequencies, antennas can interfere with each other if they are positioned too close together. Additionally, antenna modules for vehicles present the further challenge of being located in an area of ​​the vehicle where the signal is not significantly blocked by the vehicle's body. Positioning the antennas on the exterior of the vehicle would therefore be advantageous. However, the available space is even more limited here due to regulations or design constraints. Roof-mounted LTE / 5G antennas for telephones are already a known example. The other antennas mentioned above are typically positioned elsewhere.For example, antennas for radio reception are often integrated into windows, such as the rear window of the vehicle, due to their length.

[0004] The object of the present invention is therefore to provide an antenna module for a motor vehicle which makes it possible to provide as many different functions as possible in the smallest possible installation space.

[0005] This problem is solved by an antenna module with the features according to claim 1. Advantageous embodiments of the invention are the subject of the dependent claims, the description and the figures.

[0006] An antenna module according to the invention for a motor vehicle is a: Antenna module for a motor vehicle, wherein the antenna module comprises at least one AM-FM antenna and one DAB antenna, wherein the antenna module has an antenna unit comprising the combined AM-FM antenna and the DAB antenna, wherein the antenna unit has at least one first circuit board having a first height in a first direction and a first width in a second direction perpendicular to the first direction, wherein helical antenna windings of the AM-FM antenna and / or DAB antenna (6), which is at least partially designed as a planar helical antenna, are arranged on the at least one first circuit board, wherein the helical antenna windings extend at least predominantly in the second direction (x), wherein the helical antenna windings of the DAB antenna and the AM-FM antenna are arranged side by side on the common first circuit board in the second direction, wherein the AM-FM antenna has a first top-loading capacitor.which is arranged in the first direction above the first circuit board, and which is galvanically coupled to the helical antenna windings of the AM-FM antenna, wherein the DAB antenna has a second top-loading capacitor which is arranged on a circuit board edge of the first circuit board in the first direction above the helical antenna windings of the DAB antenna and is galvanically connected to the helical antenna windings of the DAB antenna, wherein the implementation of the second top-loading capacitor on the circuit board edge of the first circuit board provides a capacitive coupling of this second top-loading capacitor to the first top-loading capacitor.

[0007] The invention is based on the finding that this design of the AM / FM antenna and the DAB antenna allows, firstly, the provision of a very small electrically efficient AM / FM and DAB antenna, and secondly, that this described design allows further antennas, for example, a 5G LTE telephone antenna, to be arranged essentially perpendicular to the helical windings of the AM / FM or DAB antenna, thereby providing maximum decoupling between such a 5G LTE telephone antenna and the antenna unit. This, in turn, allows another antenna, preferably such a 5G LTE telephone antenna, to be arranged extremely close to the antenna unit, for example, within a few centimeters or even a few millimeters.Furthermore, both the AM / FM antenna and the DAB antenna can be designed, at least partially, as planar helical antennas, resulting in an extremely compact antenna unit. This, in turn, allows for an extremely compact antenna module. For the first time, this enables the integration of at least one LTE / 5G telephone antenna and a radio antenna unit with an AM antenna, an FM antenna, and a DAB antenna, all within an extremely small footprint.

[0008] Accordingly, it represents a further advantageous embodiment of the invention if the antenna module further comprises at least one telephone LTE 5G antenna which is arranged on a second circuit board with a second height in the first direction and a second width in a third direction, which is different from the first and second directions.

[0009] A telephone LTE / 5G antenna is defined as an antenna designed to transmit and receive signals according to a mobile communication standard, specifically the LTE (Long Term Evolution) and 5G standards, and optionally also the 4G and / or GSM standards. The more such telephone LTE / 5G antennas are provided, the higher the data transmission rates that can be achieved. This is also known as MIMO (Multiple Input Multiple Output), as information to be transmitted can be sent and received in parallel by multiple antennas. Therefore, more antennas enable communication according to a radio standard with higher data rates, such as 5G. For example, two such antennas can provide communication according to the 4G standard, and four such antennas can provide communication according to the 5G standard.The term "telephone LTE-5G antenna" should therefore be understood to mean that these telephone LTE-5G antennas can be used for communication according to the 5G standard, but not that a single such antenna would be sufficient for this purpose. However, mobile communication with lower data rates than those specified by the 5G standard can already be provided with a single such telephone LTE-5G antenna.

[0010] An AM (Amplitude Modulation) antenna is understood to be, in particular, an antenna designed for transmitting and receiving signals in the medium wave range, especially in the range of approximately 0.5 MHz to approximately 2 MHz. Similarly, an FM (Frequency Modulation) antenna is designed to receive and / or transmit signals in the range between 87.5 MHz and 108 MHz, and a DAB (Digital Audio Broadcasting) antenna to receive and / or transmit signals in the range between 174 MHz and approximately 240 MHz. Furthermore, a combined AM-FM antenna is understood to be an antenna in which the AM and FM antennas share a common feed point. In addition, the AM and FM antennas may also share the corresponding helical antenna windings arranged on the first circuit board.Due to the different frequency ranges of AM and FM, there is no risk of negatively impacting reception quality. This can be advantageously used to design an extremely compact and efficient antenna. Another way to improve or ensure good reception quality for AM and FM from a common input point is to design the crossover or filter using SMD (Surface Mounted Device) components on the main circuit board of the respective amplifiers.

[0011] By incorporating an additional top-mounted capacitor as part of the AM / FM or DAB antenna, the antenna unit's design can be further reduced in size, as will be described in more detail later. In other words, the AM / FM or DAB antenna can also be designed in two parts, with one part provided by the top-mounted capacitor and the other part by the corresponding helical antenna windings.

[0012] Both the combined AM / FM antenna and the DAB antenna can be provided as planar helical antennas, i.e., except for their respective top-loading components. The AM / FM antenna can be implemented on a separate circuit board from the DAB antenna, or on the same board. The latter is particularly preferred, as it allows for a significantly more compact antenna unit. Accordingly, it is a further advantageous embodiment of the invention if the helical antenna windings of the DAB antenna and the AM / FM antenna are arranged on the common first circuit board. It is also advantageous if the helical antenna windings of the DAB antenna and the AM / FM antenna are arranged side by side in the second direction. However, it is also conceivable that they are arranged one above the other in the first direction.In this case, it would be necessary to provide an electrically conductive connection from the higher-positioned antenna to its associated base point on the underside of the circuit board, oriented in the opposite direction to the first direction. This creates an electrically conductive area that extends essentially in the opposite direction to the first direction, which has disadvantages regarding decoupling from the phone LTE 5G antenna, which is largely oriented in the first direction. Accordingly, it is very advantageous if the DAB antenna and the AM / FM antenna, or at least their helical antenna windings, are arranged side by side in the second direction. This further improves decoupling from the phone LTE 5G antenna, as the antenna components of the DAB and AM / FM antennas that run parallel to the first direction can be minimized.

[0013] Furthermore, considering the direction of rotation of the helical antenna windings is very advantageous for their design, as this direction influences the coupling between the individual antennas and thus the antenna efficiency profile. The same direction of rotation for the AM / FM antenna and the DAB antenna is preferred. However, opposite directions of rotation are also conceivable.

[0014] As already mentioned, the invention further provides that the AM / FM antenna has a first top-loading capacitor arranged in the first direction above the first circuit board and galvanically coupled to the helical antenna windings of the AM / FM antenna, while the DAB antenna has a second top-loading capacitor arranged on a circuit board edge of the first circuit board in the first direction above the helical antenna windings of the DAB antenna and galvanically connected to the helical antenna windings of the DAB antenna. In an unclaimed embodiment, the DAB antenna and the AM / FM antenna could, in principle, also use a common top-loading capacitor, i.e., be galvanically connected to a common top-loading capacitor. However, by assigning a separate second top-loading capacitor to the DAB antenna, improved decoupling can be provided.

[0015] Additionally, by placing the second capacitive capacitor on the edge of the circuit board, capacitive coupling between this second capacitive capacitor and the first capacitive capacitor can be provided. The second capacitive capacitor can therefore be very small and, for example, limited to the aforementioned circuit board edge, which represents at least part of a side edge of the first circuit board. The first capacitive capacitor is preferably not located on the first circuit board itself, but is provided, for example, by a separate area above it. There are several ways to couple the first capacitive capacitor to the first circuit board. Preferably, the coupling is achieved via an electrically conductive element, which preferably allows for tolerance compensation in the first direction. This makes it easier to arrange the first capacitive capacitor on a component separate from the first circuit board.For example, the coupling can be achieved via a spring or a contact foam. Such a contact foam would then contain, for instance, metallic particles to ensure electrical conductivity. However, the contacting of the first top-loading capacitor of the AM / FM / DAB antenna can also be achieved differently, for example, by clamping. Furthermore, there are numerous possibilities for the design of the first top-loading capacitor. This top-loading capacitor can be implemented, for example, as a mounted metal sheet (e.g., stamped or deep-drawn) or as an adhesive film on a substrate. It can also be printed onto a substrate. This substrate could, for example, be a protective cap in which the module components of the antenna module are arranged.

[0016] Since the invention and its embodiments advantageously make it possible to provide an antenna module with numerous antennas in an extremely small installation space, it is preferred to house this antenna module in the roof area of ​​a motor vehicle under an outer hood of the vehicle, which is also referred to as a shark fin. The protective cap is then located accordingly below this outer hood. The roof-mounted capacitor, in particular the first roof-mounted capacitor, can then, for example, be arranged on the protective cap or integrated into the outer hood, i.e., the shark fin itself. The roof-mounted capacitor can also be provided only as a film arranged on a suitable carrier. In this case, the film can also be provided with a conductor track structure. Such a conductor track structure can be designed as a resonant conductor track structure and improve decoupling.

[0017] In a further highly advantageous embodiment of the invention, the AM-FM antenna exhibits higher efficiency in a first specific frequency range than in a second specific frequency range, particularly wherein the first specific frequency range corresponds to the FM frequency range and the second frequency range to the DAB frequency range. Furthermore, it is preferred that the DAB antenna exhibits lower efficiency in the first frequency range than the AM-FM antenna and lower efficiency than in the second efficiency range, in which the DAB antenna also exhibits higher efficiency than the AM-FM antenna. This can be achieved through a geometric design of the AM-FM antenna and the DAB antenna. These different efficiency ranges provide natural decoupling of the DAB antenna from the AM-FM antenna.The DAB antenna is preferably designed to exhibit both series and parallel resonances within the DAB frequency band (i.e., the second frequency range), while the AM / FM antenna is designed to exhibit only a series resonance within the FM frequency band (i.e., the first frequency range). The FM antenna also has a significantly lower efficiency at its feed point, at least in a sub-range of the DAB band, thus providing natural decoupling from the DAB antenna in at least a sub-range of the DAB band. This is achieved by placing the parallel resonance of the AM / FM antenna near the beginning of the DAB band. The DAB antenna, on the other hand, has a lower efficiency in the FM band.This is made possible by its size and optional decoupling measures on the common circuit board, such as at least one slot, preferably in the first direction between the helix antenna windings of the AM-FM antenna and the DAB antenna.

[0018] Furthermore, the first LTE-5G telephone antenna and the antenna unit can be connected to a common mainboard or circuit board. This board can, for example, be oriented essentially parallel to the vehicle roof when the antenna module is installed as intended. The directional terms used below, such as longitudinal direction, vertical direction, and transverse direction, also refer to the intended installation position of the antenna module in the vehicle.

[0019] It should be noted that the antenna module according to the invention and its embodiments are preferably used in a motor vehicle, but the use of the antenna module is not limited to the automotive sector. Such an antenna module can be used anywhere and is particularly advantageous where many antenna functions need to be provided in the smallest possible installation space.

[0020] Furthermore, it is preferred that the respective circuit boards of the antenna unit and the first telephone LTE 5G antenna are arranged essentially perpendicular to this main circuit board. This allows for optimal radiation characteristics of the respective antennas.

[0021] As mentioned above, it is particularly advantageous if the first telephone LTE-5G antenna, or its conductor track structure, is arranged essentially perpendicular to the direction of the helical antenna windings of the DAB antenna and the AM / FM antenna. Accordingly, it is a further preferred embodiment of the invention if the third direction, in which the width of the second circuit board of the first telephone LTE-5G antenna extends, has an angle to the first and second directions that is between 80 degrees and 100 degrees, and preferably approximately 90 degrees. At 90 degrees, the decoupling between the first telephone LTE-5G antenna and the antenna unit is maximized. For better illustration, with reference to the intended installation position of the antenna module on the vehicle, the first direction should run vertically in the vehicle, the second direction longitudinally in the vehicle, and the third direction transversely in the vehicle.The first LTE-5G phone antenna extends essentially vertically and laterally along the vehicle, while the helical antenna turns of the DAB and AM / FM antennas extend essentially horizontally along the vehicle's longitudinal axis and are arranged one above the other in the first direction. The slopes of the respective helical antenna turns are preferably kept as small as possible, as this minimizes the z-direction component. This maximizes the decoupling from the LTE-5G phone antenna, enabling an extremely compact design. Preferably, the helical antenna turns have a slope relative to the horizontal of less than 5 degrees, preferably less than 3 degrees, for example, 2.2 degrees.

[0022] Further features of the first telephone LTE-5G antenna allow for an even greater reduction in decoupling from the AM / FM / DAB antenna unit. For example, it is another highly advantageous embodiment of the invention if the at least one first telephone LTE-5G antenna has a first antenna arm, which is assigned to a first frequency range, particularly for frequencies greater than 1 gigahertz, and a second antenna arm, which is assigned to a second frequency range, particularly for frequencies less than 1 gigahertz, wherein the first and second antenna arms are capacitively coupled to each other and galvanically isolated from each other. This design allows for a particularly efficient avoidance of excessive coupling with the AM antenna of the antenna unit.If these two arms were galvanically connected, this would again provide a very large capacitance, especially coupling with the AM antenna. This design is based on the idea that the total capacitance can be reduced by connecting two individual capacitors in series, compared to connecting them in parallel. This can be achieved through the capacitive coupling of the two antenna arms, particularly in contrast to a galvanic connection, which exhibits high capacitance in the AM range. Furthermore, an inductive extension can also be provided for the second antenna arm. This can be designed as a spiral-shaped conductor that is galvanically connected to the second arm. The first arm, for higher frequencies above 1 gigahertz, can thus capacitively excite the second arm, or rather the extension, for lower frequencies below 1 gigahertz.Thus, a capacitance exists between the arm for the higher frequencies and the arm for the lower frequencies. The capacitive coupling area is decisive for the efficiency and the impedance. This can advantageously be used for decoupling from the AM antenna. Furthermore, it is advantageous if the arm for the lower frequencies, i.e., the second antenna arm, has its own capacitive loading on the antenna board, i.e., the second board. This second antenna board can therefore have a first side and a second board side opposite the first.For example, the first antenna arm for the higher frequencies can be located on the first side of the circuit board, and the second arm for the lower frequencies on the second side. A top-loading capacitor for the second arm can also be located on the first side of the board and galvanically connected to the second antenna arm via a through-hole via. This allows for a particularly efficient first 5G LTE telephone antenna with maximum decoupling from the antenna unit.

[0023] Additionally, the first LTE-5G phone antenna can have a high-impedance connection to ground for antenna detection. This high-impedance connection can be provided by a coil that ensures high-frequency signal components are coupled into the LTE-5G phone antenna and do not leak to ground. This allows a defect or failure of the antenna to be detected, which is important, for example, for the eCall function.

[0024] In a further highly advantageous embodiment of the invention, the antenna module comprises at least one second LTE-5G telephone antenna, wherein the AM-FM-DAB antenna unit is arranged between the first LTE-5G telephone antenna and the second LTE-5G telephone antenna, in particular wherein the second LTE-5G telephone antenna is arranged on a third circuit board that is oriented perpendicular to the second circuit board of the first LTE-5G telephone antenna. The data transmission rate achievable with the antenna module via a mobile network can be increased by means of an additional LTE-5G telephone antenna. Simultaneously, such a second LTE-5G telephone antenna, together with the first LTE-5G telephone antenna, can be provided in an extremely compact design with maximum decoupling.This can be achieved, firstly, by positioning the two LTE-5G phone antennas as far apart as possible, for example, by using the antennas furthest away from each other in the second direction on the antenna module, so that the antenna unit and optionally other antennas are positioned between these first and second LTE-5G phone antennas. Secondly, the third circuit board of the second LTE-5G phone antenna is oriented perpendicular to the second circuit board of the first LTE-5G phone antenna. Additionally, the third circuit board is also essentially perpendicular to the aforementioned main circuit board and is therefore preferably oriented perpendicular to the transverse direction of the vehicle.

[0025] The second LTE-5G phone antenna can also be designed for a frequency range below one gigahertz. It is also conceivable that the second LTE-5G phone antenna is configured identically to the first. However, it is also possible that, for example, the first and second antenna arms of the second LTE-5G phone antenna are not capacitively separated from each other in this case, since the second LTE-5G phone antenna may be located further away from the antenna unit than the first LTE-5G phone antenna.

[0026] Furthermore, as provided for in another embodiment of the invention, it is very advantageous if the antenna module includes a GNSS (Global Navigation Satellite System) antenna. In principle, this can also be arranged at any point within the antenna module. However, it is particularly advantageous if such a GNSS antenna is arranged between the AM / FM / DAB antenna unit and the second LTE / 5G phone antenna. A GNSS antenna can also be part of the antenna module independently of the presence of the second LTE / 5G phone antenna. However, if the second LTE / 5G phone antenna is present in the antenna module, as described above, it is advantageous if the GNSS antenna is located between this second LTE / 5G phone antenna and the antenna unit. This allows the distance between the two LTE / 5G phone antennas to be maximized.This GNSS antenna receives its signals from satellites and is therefore designed for signal radiation in the first direction, or optimized with respect to this radiation direction.

[0027] It is particularly advantageous if the GNSS antenna is designed as a patch antenna. This allows the GNSS antenna to be integrated into the antenna module in a particularly compact manner. At the same time, this provides a radiation direction in the first direction. Furthermore, a patch antenna is extremely efficient.

[0028] Alternatively, the GNSS antenna can also be configured as a curved dipole antenna with capacitive excitation on a circuit board, perpendicular to the second 5G-LTE-GSM antenna (i.e., the second 5G-LTE-5G antenna) and parallel to the first 5G-LTE-GSM antenna (i.e., the first 5G-LTE-5G antenna). This is based on the following finding: When the GNSS antenna is configured as a patch antenna, particularly when positioned directly next to the antenna unit with the very large first top-loading capacitance, it has been shown that the first top-loading capacitance has a very strong shielding effect on the patch antenna, which is very flat in the first direction. This shielding effect can be significantly reduced if the GNSS antenna is instead designed as a curved dipole antenna on a circuit board perpendicular to the second 5G-LTE-GSM antenna and parallel to the first 5G-LTE-GSM antenna with capacitive excitation.The GNSS antenna essentially has the shape of a downward-opening parabola, with the downward direction being the opposite of the first direction. This allows for increased radiation in the first direction. Furthermore, this type of GNSS antenna extends significantly higher in the first direction, thus reducing the shielding effect of the first roof capacitance. Unlike the patch antenna mentioned above, however, this curved dipole antenna does not radiate circularly polarized signals, but only linearly polarized signals. This is perfectly adequate for the desired signal strength, although there is a loss of 3 dB compared to optimal circular polarization.

[0029] However, additional antennas not yet described can also be arranged on the first side of the main circuit board. For example, it is advantageous to have at least one V-to-X antenna on the first side of the main circuit board. A V-to-X antenna, also called a Car-to-X antenna, enables communication between the vehicle and another vehicle or any other communication-enabled device, for example, according to the WLANp standard. Due to its typical bandwidth, there is no significant coupling risk with the other antennas. It is particularly efficient if such a V-to-X antenna is located, for example, on the same second circuit board as the first LTE-5G phone antenna and / or the same third circuit board as the second LTE-5G phone antenna. For example, two such V-to-X antennas can also be provided, one on the second circuit board and one on the third. The front V-to-X antenna, which, for example,The antenna closer to the front of the vehicle can be positioned laterally, next to the second LTE-5G phone antenna, instead of on the third circuit board. The V-to-X antennas emit and receive in a frequency range of approximately 5 gigahertz and can therefore be very small.

[0030] It is also advantageous to have two additional 5G LTE telephone antennas arranged on the first side of the main circuit board. These can be located in an area between the antenna unit and the second 5G telephone antenna in the second direction, and, for example, in the third direction next to the GNSS antenna, particularly on both sides of it. These third and fourth 5G telephone antennas are preferably designed only for frequencies greater than 1 gigahertz, so that they can be arranged significantly closer to each other and to the first and second 5G telephone antennas, respectively. In the case of an eCall, this can generally be transmitted via any 5G telephone antenna.The eCall antenna, located on the inside of the main circuit board (the second side), serves solely as a well-protected backup antenna. It can be used, for example, in the event of an accident or if the other LTE / 5G phone antennas fail. Similarly, the other antennas located inside the vehicle, such as the WLAN (Wireless Local Area Network) and / or UWB (Ultra-Wideband) antennas, do not require a particularly long range. This allows for their simple integration on the other side of the main circuit board, facing the vehicle interior, without unduly compromising signal quality.

[0031] In a further highly advantageous embodiment of the invention, the antenna module comprises a main circuit board, wherein the first telephone LTE-5G antenna and the antenna unit are arranged on a first side of the main circuit board, and wherein the antenna module has at least one antenna arranged on a second side of the main circuit board opposite the first side, in particular wherein the at least one antenna is an eCall antenna and / or a UWB antenna and / or a WLAN antenna and / or another telephone LTE-5G antenna. Thus, numerous additional antennas can advantageously be arranged, so to speak, below the main circuit board and therefore within the interior of the vehicle or facing the interior of the vehicle.The internal antennas and components, such as the aforementioned backup antenna for eCall or the WLAN antennas, as well as other antennas for other services like 5G, can be arranged under the vehicle roof inside a box.

[0032] In total, numerous different antennas for numerous different functions can be provided in a compact antenna module in a very small installation space. Optionally, such an antenna module, particularly on the second side of the main circuit board, can also include and integrate other electrical and / or electronic components, such as tuners, transceivers, receivers, control units, or similar devices. In other words, the antenna module can include an integrated tuner and / or transceiver and / or receiver and / or a bus system. However, this is not a requirement. In a further embodiment of the invention, the antenna module does not include an integrated tuner, transceiver, receiver, or bus system.In this case, however, it is preferred that the antenna module has a matching network and / or an amplifier for at least one antenna encompassed by the antenna module, wherein a coaxial cable for coupling to a module-external tuner or transceiver or receiver is connected to the matching network and / or amplifier.

[0033] The antenna module can be coupled to a vehicle roof in a variety of ways. It is preferred that the antenna module has a good galvanic connection to the roof, which can be achieved without screws or with one or more screws. This galvanic connection establishes a ground connection to the roof. The roof antenna module can be a single piece or a two-piece design, as will be explained in more detail later with reference to the figures. In all cases, however, the antennas have at least one electrical contact with the main circuit board to enable a connection to the receivers and transceivers. These can also be integrated into the antenna module or located separately.

[0034] Furthermore, a motor vehicle equipped with an antenna module according to the invention or one of its embodiments shall also be considered to belong to the invention. The antenna module is then preferably arranged on the roof of the vehicle, in particular below a hood or shark fin, as already described.

[0035] The invention also includes combinations of the features of the described embodiments.

[0036] An embodiment of the invention is described below. The following is shown: Fig. 1 a schematic representation of an antenna module for a motor vehicle for arrangement on a vehicle roof without receiver and tuner integration according to an embodiment of the invention; Fig. 2 a schematic top view of a first side of the first circuit board of the antenna unit, on which the helical antenna windings of the AM-FM antenna and the DAB antenna are mounted, according to an embodiment of the invention; Fig. 3 a schematic top view of a second side of the first circuit board of the antenna unit with the AM-FM antenna and the DAB antenna, according to an embodiment of the invention; Fig. 4 a schematic representation of the efficiency of the AM-FM antenna and the DAB antenna according to an embodiment of the invention; Fig. 5 a schematic representation of the first telephone LTE 5G antenna in a top view of a first side according to an embodiment of the invention; Fig.6. A schematic representation of the first telephone LTE-5G antenna in a top view of a second side opposite the first side, according to an embodiment of the invention; Fig. 7. A schematic representation of the first telephone LTE-5G antenna in a sectional view according to an embodiment of the invention; Fig. 8. A schematic representation of an antenna module for a motor vehicle for mounting on a vehicle roof according to a one-piece mounting concept with integrated transceivers and tuners, according to an embodiment of the invention; and Fig. 9. A schematic representation of an antenna module according to a two-piece mounting concept according to a further embodiment of the invention.

[0037] The embodiment described below is a preferred embodiment of the invention. In this embodiment, the described components each represent individual features of the invention that can be considered independently of one another. Each of these features further develops the invention independently and can therefore be considered part of the invention individually or in a combination other than that shown. Furthermore, the described embodiment can also be supplemented by other features of the invention already described.

[0038] In the figures, functionally identical elements are each provided with the same reference symbols.

[0039] Fig. 1 Figure 1 shows a schematic representation of an antenna module 1 for a motor vehicle 2, of which only the vehicle roof 3 and the outer hood 4 mounted on the vehicle roof 3, also referred to as a shark fin, are shown as examples. The antenna module 1 is designed as a multifunctional and multiband antenna module 1 in a very small installation space. The antenna module 1 comprises an antenna unit 5, which can also be referred to as an AM-FM-DAB antenna 5, since it includes both a DAB antenna 6 and a combined AM-FM antenna 7. Furthermore, the antenna module 1 has at least one first LTE-5G telephone antenna 8, which is arranged very close to the antenna unit 5. In addition, this example includes a second telephone LTE-5G antenna 9, a third and fourth telephone LTE-5G antenna 10, 11, a GNSS antenna 12, and two V-to-X antennas 13, 14, from antenna module 1.These antenna module components are arranged on a main circuit board 15, which in turn is mounted on a carrier 16, also known as a chassis. A protective cover 17 is arranged over at least most of these antenna module components. Except for one roof capacitor 18 assigned to antenna unit 5, all other antennas are located under this protective cover 17. This antenna module 1 can also be mounted to the roof 3 of the vehicle 2 via a screw connection 20. In this example, no tuner or transceiver is integrated into the antenna module 1, but the necessary amplifiers and matching networks with connected coaxial cables are integrated. Further examples with integrated receivers and tuners will be explained in more detail later.

[0040] The invention and its embodiments advantageously enable the provision of an extremely compact antenna module 1, in which, for example, the highest antenna, provided here by the antenna unit 5, measures less than 10 centimeters in the first direction, corresponding to the z-direction shown here, and in particular only approximately 7 centimeters in the first direction. With respect to the intended installation position of this antenna module 1 relative to the motor vehicle 2, the z-direction corresponds to the vehicle's vertical direction, the x-direction shown here corresponds to the vehicle's longitudinal direction, with the x-direction pointing in particular towards the front of the vehicle, and the y-direction corresponds to the vehicle's transverse direction. The z-direction is also referred to as the first direction, the y-direction as the third direction, and the x-direction as the second direction.The main challenge in providing such a compact antenna module 1 lies not only in making the individual antennas themselves as small and compact as possible, but also, and perhaps more importantly, in sufficiently decoupling them from one another to prevent mutual interference or disruption. This applies particularly to the arrangement of the antenna unit 5 in relation to the first LTE-5G phone antenna 8. To provide the highest possible data rate, especially over the mobile network, for example according to the 4G or 5G standard, it is advantageous for the antenna module to have as many LTE-5G phone antennas 8, 9, 10, 11 as possible. Two such antennas 8, 9, 10, 11 are sufficient for 4G communication, while four such antennas 8, 9, 10, 11 are required for 5G communication.The designation "Telephone LTE-5G antenna 8, 9, 10, 11" should therefore be understood to mean that these telephone LTE-5G antennas 8, 9, 10, 11 can be used for communication according to the 5G standard, but not that a single such antenna 8, 9, 10, 11 would be sufficient for this purpose. However, mobile communication with lower data transmission rates than those specified by the 5G standard can be provided with a single such telephone LTE-5G antenna 8, 9, 10, 11. Both the first and the second telephone LTE-5G antenna 8, 9 can transmit and receive data in a frequency range below 1 gigahertz as well as above 1 gigahertz. To provide the best possible decoupling of these two telephone LTE 5G antennas 8, 9, it is advantageous to arrange them as far apart as possible, as is done, for example, in . Fig. 1 This is illustrated by making these two antennas 8 and 9 the antennas of antenna module 1 furthest apart in the x-direction. However, due to the size of antenna unit 5, it is necessary to position it very close to the first telephone LTE-5G antenna 8. The challenge here is to ensure sufficient decoupling between this first telephone LTE-5G antenna 8 and antenna unit 5, as well as sufficient decoupling of the antennas integrated into antenna unit 5, namely the DAB antenna 6 and the AM / FM antenna 7. How this can be achieved will now be explained in more detail below.

[0041] Additionally, this AM / FM / DAB antenna 5 is positioned in the highest area of ​​the roof module 1 and is also implemented in two parts. A first part 5a is located below the protective cap 17, and the second part 5b represents the aforementioned roof capacitor 18. The roof capacitor 18 of the AM / FM / DAB antenna 5 can be arranged on the protective cap 17, as shown, or integrated into the outer cover 4, i.e., the shark fin. The roof capacitor makes contact with the first part 5a of the AM / FM / DAB antenna 5 by means of a contact element 21, which is preferably a spring or an electrically conductive foam material. The contact, i.e., the contact element 21, of the first part 5a of the AM / FM / DAB antenna 5 can also be achieved differently, for example, by clamping. Furthermore, this roof capacity can be realized as a mounted, for example stamped or deep-drawn, sheet metal or glued foil.It can also be printed on the protective cap 14. If the roof capacitance 18 is a foil, it can have a conductor track structure or be designed as a resonant conductor track structure.

[0042] The first part, 5a, is implemented as a vertically oriented PCB (Printed Circuit Board) antenna. The first part, 5a, of this AM-FM-DAB antenna 5 is shown in detail in... Fig. 2 und Fig. 3 The arrangement shown is as follows. Various other variants of this arrangement, i.e., of the antenna module 1 shown, may exist, for example, by omitting the V-to-X antennas. However, a major advantage of the invention is the provision and presence of the AM-FM-DAB antenna unit, particularly in its described implementation.

[0043] Fig. 2 This shows a schematic representation of a top view of a first page 22 of the first part 5a and Fig. 3 A schematic top view of the second page 23, opposite the first page 22. Both the DAB antenna 6 and the AM / FM antenna 7 comprise a part 6a, 7a, which is designed as a planar helical antenna. These parts 6a, 7a are thus designed in the form of planar helical turns 6a, 7a, which are arranged on a circuit board, in this example a common first circuit board 24. The thickness of this circuit board in the y-direction can be between 0.5 millimeters and 2 millimeters and is 1 millimeter in this example. The individual helical antenna turns 6a, 7a can be applied as conductor tracks on this circuit board 24, with the individual front and back conductor track sections being connected to each other by corresponding vias 25, of which, for the sake of clarity, Fig. 2 und Fig. 3 Only one is provided with a reference numeral. These planar helical antennas 6a, 7a are thus provided, in a sense, in the form of a flattened coil with several turns arranged one above the other in the z-direction. Furthermore, the helical antenna turns 7a of the AM-FM antenna 7 are galvanically connected to the first top-loading capacitor 18 via the coupling element 21, this galvanic connection being designated 26 in this case. The DAB antenna 6 has its own top-loading capacitor 27, which is also arranged on the circuit board 24, in particular on an edge of the circuit board, preferably an upper edge of the circuit board 24. The DAB antenna 6 therefore preferably has no galvanic contact with the first top-loading capacitor 18, but can be capacitively coupled to the first top-loading capacitor 18 via its own capacitive load, which is implemented as a second top-loading capacitor 27 on the edge of the circuit board.This allows for better decoupling between the DAB antenna 6 and the AM-FM antenna 7. To further enhance this decoupling, a slot 28 parallel to the z-direction is also provided between the DAB antenna 6 and the AM-FM antenna 7 or their respective helix antenna windings 6a, 7a.

[0044] The AM antenna and the FM antenna, which are provided here as a combined AM-FM antenna 7, accordingly share a common antenna base 29. The DAB antenna 6 has its own base 30. These bases 29 and 30 are electrically connected to the main circuit board 15.

[0045] In principle, it is also conceivable that the DAB antenna 6 and the AM / FM antenna 7 are provided on separate circuit boards; however, arranging them on a common circuit board 24 offers significant component advantages. Furthermore, it would also be conceivable to provide the DAB antenna 6 and the AM / FM antenna 7 as a combined antenna, still with two base points 29, 30, but with shared windings 6a, 7a, by arranging these respective antenna parts 6a, 7a not side by side in the x-direction as shown here, but, for example, one above the other in the z-direction. For instance, the antenna windings 6a of the DAB antenna 6 could also be arranged above the antenna windings 7a of the AM / FM antenna 7 in the z-direction and be galvanically connected to them. The individual windings 6a, 7a can then extend over almost the entire width in the x-direction of the circuit board 24, which increases its efficiency.The base point 30 associated with the DAB antenna 6 can be implemented via a tap. Such a tap can be implemented by a conductor running in the z-direction. However, in order to minimize coupling to the extremely closely located first telephone LTE-5G antenna 8, it is preferred to design the first part 5a of the antenna unit 5 as shown in . Fig. 2 und Fig. 3 This is achieved by providing the DAB antenna 6 and the AM / FM antenna 7, each with separate antenna windings 6a, 7a, positioned side by side in the x-direction. The purpose of this is to minimize the electrically conductive components of the antenna unit 5 extending in the z-direction. This advantageously provides maximum decoupling from the adjacent LTE / 5G telephone antenna 8, which, as will be explained in more detail later, is mounted on a circuit board that extends vertically in the z-direction and horizontally in the y-direction, and is thus oriented perpendicular to the first circuit board 24 of the first part 5a of the antenna unit 5. Furthermore, because the antenna parts 6a, 7a are designed as planar helical windings 6a, 7a, these windings have virtually no extension in the y-direction.Accordingly, maximum decoupling from the telephone LTE-5G antenna 8 can also be provided in this direction. The individual windings 6a, 7a are preferably aligned as horizontally as possible, i.e., parallel to the xy-plane. In the present example, this is achieved by the windings 6a, 7a being designed as running horizontally on the first side 22 of the circuit board 24, and on the second side 23 with the smallest possible inclination relative to the horizontal, which is preferably not greater than 5 degrees, particularly preferably less than 3 degrees, for example 2.2 degrees.

[0046] Furthermore, to ensure the best possible decoupling between the DAB antenna 6 and the AM / FM antenna 7, these exhibit different efficiencies in different frequency ranges, which can also be described as antenna gain, as shown in Fig. 4 This is illustrated. Fig. 4 Three exemplary efficiency curves 7b for the FM antenna 7 and two exemplary efficiency curves 6b for the DAB antenna 6 are shown, each as a function of frequency f. As can be seen, the FM antenna 7 preferably exhibits a significantly higher efficiency E in a first frequency range F1 than, on the one hand, the DAB antenna 6, and on the other hand, than the FM antenna 7 in a second frequency range F2, in which its efficiency E is preferably significantly lower than that of the DAB antenna 6. The first frequency range F1 corresponds to the FM frequency range and is limited, for example, by the lower cutoff frequency f1 and the upper cutoff frequency f2. f1 can be, for example, 87.5 megahertz and f2, for example, 108 megahertz. The second frequency range F2 represents the DAB frequency range and extends from a third frequency f3 to a fourth frequency f4.The third frequency f3 can be, for example, 174 megahertz and the fourth frequency f4, for example, 240 megahertz. To achieve this, the corresponding antennas 6, 7 can be designed appropriately with regard to their geometry.

[0047] The geometric properties of an antenna can be used to influence, in particular, its series and parallel resonances. The DAB antenna 6 is preferably designed to exhibit both series and parallel resonances within the DAB frequency band F2. The parallel resonance of the AM / FM antenna 7 is preferably located near the beginning of the DAB band F2. This provides natural decoupling. The lower efficiency of the DAB antenna 6 in the FM band F1 is achieved through geometric properties such as its length, as well as through the inclusion of slots, such as the one already described. Fig. 2 und Fig. 3 described slot 28.

[0048] To ensure good decoupling from the first telephone LTE-5G antenna 8, further decoupling measures can also be implemented by this first telephone LTE-5G antenna 8 itself, as will be explained in more detail below. Fig. 5 und Fig. 6 is described.

[0049] Fig. 5 This shows a schematic representation of the first telephone LTE 5G antenna 8 in a top view on a first page 31 and Fig. 6 A schematic representation of this antenna 8 in a top view of a second side 32 opposite the first side 31. This antenna 8 is also implemented as a PCB antenna 8. Accordingly, the antenna components are arranged on a corresponding second circuit board 33. Fig. 7 Figure 1 also shows a schematic illustration of this first telephone LTE-5G antenna 8 in a side view and a sectional view perpendicular to the y-axis. This telephone LTE-5G antenna 8 has two antenna arms 34, 35, which are arranged on different sides 31, 32 of the circuit board 33. The first antenna arm 34 is for high frequencies, in particular greater than 1 gigahertz, and the second arm 35 is for low frequencies, in particular less than 1 gigahertz. These two antenna arms 34, 35 are advantageously not galvanically connected to each other, but only capacitively coupled. This provides capacitive excitation for the first telephone LTE-5G antenna 8, whereby the first arm 34 for the higher frequencies capacitively excites the second arm 35 or its extension 36 for the lower frequencies.This extension 36 can in turn be arranged on the second side 32 of the circuit board 33, on which the first arm 34 is also located, with this extension 36 being galvanically connected to the second arm 35 via a through-hole 37 through the circuit board 33. Thus, a capacitance exists between the arm 34 for the higher frequencies and the arm 35 for the lower frequencies. The capacitive coupling area determines the efficiency and impedance of the antenna 8. Furthermore, the arm 35 for the lower frequencies has its own capacitive load 36, the aforementioned extension 36, on the antenna circuit board 33. This design advantageously provides particularly good decoupling from the AM antenna 7. Furthermore, the first telephone LTE 5G antenna 8 has a high-impedance connection in the form of a coil 38 to ground 39 or to the ground contact connection 39 provided on the circuit board 33 for the purpose of detection.The base of antenna 8 is designated 40. High frequencies are advantageously fed into antenna 8 through this high-impedance coil 39. A voltage tap on this coil 38 allows detection if antenna 8 fails, for example, due to a defect or accident involving vehicle 2. In such a case, the backup antenna, which will be explained in more detail later, can be used to transmit an eCall. Furthermore, arm 35 also features an inductive extension 41 for lower frequencies.

[0050] This design of the first telephone LTE-5G antenna 8 also makes it advantageously possible to position it extremely close to the antenna unit 5, as is also the case, for example, in Fig. 1 or also in Fig. 8 and Fig. 9 This illustrates the point.

[0051] Fig. 8 Figure 1 shows an antenna module 1 according to a further embodiment of the invention. Furthermore, this antenna module 1 can be configured as described above, except for the differences explained below. In particular, this antenna module 1 can also be configured to Fig. 1 The antennas described above are shown, although the third and fourth telephone LTE-5G antennas 10, 11 are not shown here as examples. Likewise, the two V-to-X antennas 13, 14 are not shown here, although they may nevertheless be part of this antenna module 1. The following Fig. 1 The aforementioned antennas are arranged on a first side 15a of the main circuit board 15, while components, which will be explained in more detail later, can also be arranged on the opposite side 15b of this main circuit board 15. In this example, the antenna module 1 is designed according to a one-piece assembly concept, according to which this assembled antenna module 1 can be inserted and mounted as a whole from below through a hole or through-opening 42 in the vehicle roof 3. In other words, in this example, the roof antenna module 1 can only be mounted from inside the vehicle. Only the external part of the module 1 is inserted through the opening 42, that is, those components that are located on the first side 15a of the main circuit board 15 and are above the chassis.The individual antennas and components of antenna module 1 on the first side 15a of the main circuit board 15 can be mounted via a separate support element 16a, a chassis that is rigidly connected to the inner part of antenna module 1. This support element 16a has a corresponding opening 43 for each antenna, through which the base(s) 29, 30, 39, 40 and those of the other antennas pass to ensure electrical contact between each antenna and the main circuit board 15. Here, 44 designates the base of the GNSS antenna 12 and 45 the base of the second telephone LTE 5G antenna 9. This antenna module 1 can be connected to the roof 3 of the vehicle 2 via a metallized foam 46. This foam can simultaneously provide tolerance compensation in the z-direction.At least the antennas located on the first side 15a of the main circuit board 15, especially the GNSS antennas 12 in this example, are all oriented perpendicular to the main circuit board 15 and are designed as individual PCB antennas. It is particularly advantageous that the first circuit board 24 of the antenna unit 5 is oriented perpendicular to the second circuit board 33 of the first telephone LTE 5G antenna.

[0052] The main circuit board 15 can be attached to the support element 16a using appropriate screws 20.

[0053] The second telephone LTE-5G antenna 9 is preferably again oriented perpendicular to the first telephone LTE-5G antenna 8 to provide maximum decoupling for it. If further telephone LTE-5G antennas 10, 11 are provided, as for example in Fig. 1 As shown, these are preferably aligned parallel to the first telephone LTE 5G antenna 8.

[0054] In this example, the GNSS antenna 12 is configured as a patch antenna. This means it is very flat with respect to the z-direction and exhibits a circular radiation pattern, directed mostly vertically upwards, i.e., in the z-direction. However, to reduce potential shielding by the top capacitance 18, this GNSS antenna 12 can also be configured as a PCB antenna, i.e., with a circuit board that is preferably oriented perpendicular to the main circuit board 15. On such a circuit board, the GNSS antenna 12 can be configured as a dipole-like antenna perpendicular to the second 5G LTE GSM antenna and parallel to the first 5G LTE GSM antenna, for example, in the form of a downward-opening arc or a downward-opening parabola, with capacitive feed.The maximum available height in the z-direction below the protective cap 17 can be utilized to implement this GNSS antenna 12. Such a dipole-like antenna solution advantageously also provides a main radiation direction in the z-direction, or a corresponding reception characteristic. In contrast to the patch antenna 12 shown here, such a dipole-like antenna solution is designed only for transmitting linearly polarized signals. Such a dipole-like antenna solution with capacitive feed on a circuit board perpendicular to the second 5G-LTE-GSM antenna and parallel to the first 5G-LTE-GSM antenna enables decoupling of this antenna in the GNSS band and allows it to function as an AM antenna.

[0055] In this example, the antenna module 1 also includes a receiver or transceiver 47 and a tuner 48. Furthermore, the antenna module can also comprise a control unit 49 and a power supply 50. These components can be arranged directly on the main circuit board 15, particularly on its second side 15b, but also partly on the first side 15a. Additional antennas are also provided on the second side 15b of the main circuit board 15, such as a WLAN antenna 51 and a backup eCall antenna 52. Although only one receiver 47 is shown here as an example, several of these can be arranged on the main circuit board 15. The following components are particularly advantageous: a telephone LTE 5G transceiver, a radio tuner, a GNSS receiver, a WLAN transceiver and a V-to-X receiver, especially per V-to-X antenna 13, 14, if present.All these receivers and transceivers are preferably integrated in the lower box 53 on the main circuit board 15. All antennas also have at least one electrical contact with the main circuit board 15 to ensure a connection to the receivers and transceivers. The antenna module can also have at least one or more digital interfaces or at least one connector 54, via which the antenna module 1 can be connected to a vehicle bus, for example a CAN bus, Ethernet, a Flexbus, and so on.

[0056] Furthermore, antenna module 1 can also be designed according to a two-part concept, as exemplified in Fig. 9 This illustrates the point.

[0057] Fig. 9 Figure 1 shows a schematic representation of the antenna module 1 according to a further embodiment of the invention. Here too, the antenna module 1 can be configured as described above, and the corresponding components and antennas can be arranged as described above. Fig. 1 and / or Fig. 8 described or depicted. The difference here lies in Fig. 9The only difference lies in the way the antenna module 1 is mounted on the roof 3 of the vehicle 2. The antenna module 1 is designed according to a two-part concept and, in this example, accordingly has two main circuit boards 15, 55. A first main circuit board 15 is assigned to the antennas arranged above the roof 3, and a second circuit board 55 to the antenna components arranged below the roof 3. The two main circuit boards 15, 55 can be electrically connected to each other through the roof 3 of the vehicle by means of a suitable connector 56. With such a two-part antenna module 1, its external part can be mounted from the outside and the internal part from the inside.

[0058] Overall, this example demonstrates how the invention provides a multifunctional and multiband intelligent roof antenna module with an integrated, very small AM / FM / DAB antenna. This module enables the integration and mounting of numerous antennas, in particular a first LTE / 5G phone antenna, an AM / FM / DAB antenna, a GNSS antenna, and at least one second LTE / 5G phone antenna, externally within a very small installation volume. The number of external antennas can be increased to 12 by integrating two V-to-X antennas, two additional LTE / 5G phone antennas, and two UWB antennas within the same volume. This volume is comparable to that of current roof antennas, which house significantly fewer antennas. Furthermore, at least two antennas, in particular an eCall backup antenna and a WLAN antenna, can be mounted internally within the vehicle.The number of internal antennas can be increased to six by adding two UWB antennas, one additional WLAN antenna, and one additional telephone LTE 5G antenna. Reference symbol list

[0059] 1 Antenna module 2 Motor vehicle 3 Vehicle roof 4 Outer hood 5 Antenna unit 5a First part of the antenna unit 5b Second part of the antenna unit 6 DAB antenna 6a Helix antenna windings of the DAB antenna 6b Efficiency curve of the DAB antenna 7 AM / FM antenna 7a Helix antenna windings of the AM / FM antenna 7b Efficiency curve of the AM / FM antenna 8 First telephone LTE / 5G antenna 9 Second telephone LTE / 5G antenna 10 Third telephone LTE / 5G antenna 11 Fourth telephone LTE / 5G antenna 12 GNSS antenna 13 V2X antenna 14 V2X antenna 15 Main circuit board 15a First side of the main circuit board 15b Second side of the main circuit board 16 Carrier 16a Carrier element 17 Protective cover 18 First top capacitor 20 Screw connection 21 Contact element 22 First circuit board side of the antenna unit 23 Second circuit board side of the antenna unit 24 First circuit board 25 Via 26 Galvanic connection 27 Second top capacitor 28 Slot 29 Base point of the AM / FM antenna 30 Base point of the DAB antenna 31 First circuit board side of the first telephone LTE / 5G antenna 32 Second33 Second board 34 First antenna arm 35 Second antenna arm 36 Extension 37 Via 38 Coil 39 Ground contact 40 Base of first telephone LTE-5G antenna 41 Extension 42 Through hole 43 Opening 44 Base of GNSS antenna 45 Base of second telephone LTE-5G antenna 46 Metallized foam 47 Transceiver 48 Tuner 49 Control unit 50 Power supply 51 WLAN antenna 52 E-call backup antenna 53 Box 54 Connector 55 Second main board 56 Connector Efficiency FFrequency F1first frequency range F2second frequency range f1first frequency f2second frequency f3third frequency f4fourth frequency

Claims

1. An antenna module (10) for a motor vehicle (2), wherein the antenna module (10) comprises at least one AM-FM antenna (7) and a DAB antenna (6), wherein the antenna module (10) has an antenna unit (5) which has the combined AM-FM antenna (7) and the DAB antenna (6), wherein the antenna unit (5) has at least a first circuit board (24) with a first height in a first direction (z) and a first width in a second direction (x) perpendicular to the first direction (z), wherein helix antenna windings (7a, 6a) of the AM-FM antenna (7) and / or DAB antenna (6), which are configured at least in part as a planar helix antenna, are arranged on the at least one first circuit board (24), wherein the helix antenna windings (7a, 6a) run at least for the most part in the second direction (x), wherein the helix antenna windings (6a, 7a) of the DAB antenna (6) and the AM-FM antenna (7) are arranged next to each other on the shared first circuit board (24) in the second direction (x), wherein the AM-FM antenna (7) has a first top loading capacity (18) which is arranged above the first circuit board (24) in the first direction (z) and is galvanically coupled to the helix antenna windings (7a) of the AM-FM antenna (7), wherein the DAB antenna (6) has a second top loading capacity (27) which is arranged on a circuit board edge of the first circuit board (24) in the first direction (z) above the helix antenna windings (6a) of the DAB antenna (6) and is galvanically connected to the helix antenna windings (6a) of the DAB antenna (6), characterised in that through the configuration of the second top loading capacity (27) on the circuit board edge of the first circuit board, capacitive coupling of said second top loading capacity with the first top loading capacity (18) is provided.

2. The antenna module (10) according to claim 1, characterised in that the antenna module (10) has at least a first telephone-LTE-5G antenna (8), which is arranged on a second circuit board (33) with a second height in the first direction (z) and a second width in a third direction (y), which is different from the first and second direction (x), in particular wherein the third direction (y) forms an angle with the first and second direction (z, x) that lies between 80° and 100°, and which is preferably 90°.

3. The antenna module (10) according to claim 2, characterised in that the at least one first telephone-LTE-5G antenna (8) has a first antenna arm (34) which is assigned to a first frequency range, in particular for frequencies greater than 1GHz, and a second antenna arm (35) which is assigned to a second frequency range, in particular for frequencies less than 1 GHz, wherein the first and the second antenna arm (34, 35) are capacitively coupled with each other and are galvanically separated from each other.

4. The antenna module (10) according to one of the preceding claims 2 or 3, characterised in that the antenna module (10) has at least a second telephone-LTE-5G antenna (9), wherein the antenna unit (5) is arranged between the first telephone-LTE-5G antenna (8) and the second telephone-LTE-5G antenna (9), in particular wherein the second telephone-LTE-5G antenna (9) is arranged on a third circuit board, which is oriented perpendicular to the second circuit board (33) of the first telephone-LTE-5G antenna (8).

5. The antenna module (10) according to claim 4, characterised in that the antenna module (10) has a GNSS antenna (12), which is arranged between the antenna unit (5) and the second telephone-LTE-5G antenna (9).

6. The antenna module (10) according to claim 5, characterised in that the GNSS antenna (12) is configured as a patch antenna.

7. The antenna module (10) according to claim 5, characterised in that the GNSS antenna (12) is configured as a curved dipole antenna with capacitive excitation on a circuit board perpendicular to the second 5G-LTE-GSM antenna (9) and parallel to the first 5G-LTE-GSM antenna (8).

8. The antenna module (10) according to any one of the preceding claims, characterised in that the AM-FM antenna (7) has a higher efficiency (E) in a first certain first frequency range (F1) than in a certain second frequency range (F2) and wherein the DAB antenna (6) has a lower efficiency (E) in the first frequency range (F1) than the AM-FM antenna (7) and a lower efficiency (E) than in the second frequency range (F2), in which the DAB antenna (6) additionally has a higher efficiency (E) than the AM-FM antenna (7).

9. The antenna module (10) according to any one of the preceding claims 2 to 7, characterised in that the antenna module (10) has a main circuit board (15, 55), wherein the first telephone-LTE-5G antenna (8) and the antenna unit (5) are arranged on a first side (15a) of the main circuit board (15, 55), wherein the antenna module (10) has at least one antenna (51, 52), which is arranged on a second side (15b) of the main circuit board (15, 55) opposite to the first side (15a), in particular wherein the at least one antenna (51, 52) represents an eCall antenna (52) and / or a UWB antenna and / or a WLAN antenna (51) and / or a further telephone-LTE-5G antenna.

10. The antenna module (10) according to any one of the preceding claims, characterised in that the antenna module (10) comprises an integrated tuner and / or transceiver and / or receiver and / or a bus system.

11. The antenna module (10) according to any one of the preceding claims 1-9, characterised in that the antenna module (10) does not comprise an integrated tuner or transceiver or receiver or a bus system, wherein the antenna module (10) has a matching network and / or an amplifier for at least one antenna comprised by the antenna module (10), wherein a coaxial cable for coupling to a tuner or transceiver or receiver external to the module is connected to the matching network and / or an amplifier.

12. The antenna module (10) according to any one of the preceding claims, characterised in that the first top loading capacity is not located on the first circuit board itself, but is provided by a separate area above this first circuit board.