Wireless network for transmitting a radio signal using a RIS

Abstract

The invention relates to connecting multiple participants in an in-vehicle radio network (N) of a motor vehicle (1) using one or more deflection devices (20) for terahertz communication. Each deflection device (20) is configured to deflect a radio signal provided by a participant designated as a transmitter to a participant in the radio network (N) configured as a receiver. For this purpose, the deflection device (20) comprises at least one reflection matrix (10) with a plurality of reflective elements (11) forming an intelligent reflective surface. Each of the reflective elements (11) is configured to modify at least one parameter of the incoming radio signal according to a predetermined configuration setting, thereby effecting the deflection.

Description

[0001] The invention relates to a motor vehicle with a radio network for transmitting a radio signal within the vehicle. The invention further relates to a communication system for implementing a radio network for a motor vehicle. Finally, the invention relates to a method for operating a corresponding communication system.

[0002] Radio networks for in-vehicle radio transmission are also known as wireless in-vehicle networks (IVNs). The purpose of such a radio network is to enable wireless data transmission between several local or stationary participants. Local here means that the participants, and thus the radio network, are within the vehicle. In-vehicle means that the radio network is limited to a local or regionally defined area, in this case the "motor vehicle" system. A limitation can be provided, for example, by an outer shell or outer skin of a motor vehicle body. In-vehicle participants are therefore, for example, components that are located in the vehicle interior.

[0003] Compared to wired data transmission, wireless data transmission offers the advantage of allowing communication between participants to take up less space and weight (due to the lack of cables). At the same time, various telecommunications services, such as telephony, video, text messaging, and broadcasts, can now be implemented wirelessly.

[0004] An example of a wireless in-vehicle network is disclosed in US 2021 / 0195669 A1. To improve reliability, a data packet is transmitted both directly between two devices (device-to-device - D2D) and from one device to the other via a relay. Communication takes place, for example, using LTE (Long Term Evolution) or 5G (fifth-generation mobile communications).

[0005] The speed of data transmission between participants is limited by the (data) transmission rate. Current transmission standards, such as LTE and 5G, can achieve transmission rates in the range of 1 to 10 Gbit / s (gigabits per second). If higher transmission rates, for example, in the terahertz (THz) range, are to be used, the existing IVNs reach their limits. Due to its physical properties, terahertz communication is the most important prerequisite for transmitting signals in the terabits per second (Tbit / s) range. It is intended for use, for example, in 6G (sixth-generation) communication.

[0006] However, terahertz transmission has the disadvantage that the transmission channel or path of a terahertz signal can easily be interrupted or attenuated by objects such as walls or people in the surrounding area. Implementing terahertz communication is particularly difficult in an IVN due to the multitude of obstacles, such as a vehicle seat or a passenger.

[0007] The object of the present invention is to reliably realize in-vehicle radio signal transmission in the terahertz range.

[0008] The problem is solved by the subject matter of the independent patent claims. Advantageous developments of the invention are disclosed by the dependent patent claims, the description, and the figures.

[0009] The invention is based on the realization that solutions are required for in-vehicle terahertz communication that dynamically create alternative transmission paths between participants in the radio network. This allows obstacles to be bypassed and data transmission to be realized at the desired high data rates. For this purpose, so-called intelligent reflecting surfaces (IRS), also known as reconfigurable intelligent surfaces (RIS), can be used. RIS technology makes it possible to control or adapt the transmission paths or radio signal paths for terahertz signals, which is crucial given the multitude of different obstacles in the vehicle interior.

[0010] RIS are known elements for redirecting radio signals. For this purpose, an RIS comprises a reflection matrix with a plurality of reflective or scattering elements. The reflective elements are designed to modify the properties of an electromagnetic wave, i.e., the radio signal to be transmitted, in such a way that the incoming radio signal is adjusted to the desired extent. For example, each of the elements is capable of steering an electromagnetic wave, making them suitable for beamforming.

[0011] The elements are based on metasurface technology. A metasurface, also called an electromagnetic metasurface, is an artificial material with a thickness below the wavelength of the radio signal to be redirected. It is thus essentially a two-dimensional, very thin, film-like structure with the ability to model the behavior of an electromagnetic wave through specific boundary conditions instead of structural parameters, as would be the case with a thicker, three-dimensional structure. This allows an RIS to control the wavefront of an electromagnetic wave, for example, by imparting a local gradient phase shift to the incoming wave, which leads to an extension of Snell's law of refraction and the laws of reflection.In this way, each of the elements in the reflection matrix can be used, for example, as a beam deflector, lens, or prism. This allows RIS to be configured to change the scattering characteristics of the incoming radio signal, thus specifying the transmission channel or propagation path for the radio signal.

[0012] RIS technology using RIS for signal transmission is known from the state of the art.

[0013] For example, US 2022 / 0123803 A1 discloses a way to amplify a power signal in wireless communication systems using an intelligent reconfigurable surface.

[0014] US 2021 / 0126359 A1, for example, discloses a wireless network in which at least one electronic device comprises an intelligent reflective surface.

[0015] In order to reliably enable in-vehicle terahertz communication, the invention proposes, according to one aspect, a motor vehicle with a radio network for transmitting a radio signal within the vehicle. The motor vehicle comprises at least one in-vehicle transmitting device and at least one in-vehicle receiving device. The respective transmitting device and the respective receiving device are designed to be connected to one another in the radio network. This means that the respective transmitting device and the respective receiving device are connected or connectable to one another in the radio network. The respective transmitting device and the respective receiving device can thus be understood as participants in the radio network.

[0016] The at least one transmitting device is configured to provide the radio signal for transmission to the at least one receiving device. The at least one receiving device is configured to receive the provided radio signal to perform a predetermined function. In other words, the respective transmitting device (hereinafter referred to as the transmitter) is a participant that, for example, sends or transmits data. The respective receiving device (hereinafter referred to as the receiver), in contrast, is a participant that, for example, receives or captures the transmitted data.

[0017] The motor vehicle also includes a deflection device for deflecting the radio signal. For this purpose, the deflection device comprises at least one reflection matrix with a plurality of reflective elements that form an intelligent reflective surface, i.e., the aforementioned RIS. Each of the reflective elements is configured to modify at least one parameter of the incident radio signal, which was provided by the at least one transmitting device, according to its respective predetermined configuration setting and thereby redirect it to the at least one receiving device.

[0018] The deflection device can thus be used to create an additional or alternative transmission channel in the radio network between the respective transmitter and the respective receiver. The transmitter and receiver are connected to one another via one or more respective deflection devices. This means that the transmitter, receiver and deflection device together form the radio network. The transmitter and receiver can be understood as active participants or peripheral devices in the radio network. The respective deflection device can be understood as a passive component in the radio network. Active here means that the participants are used for signal processing or signal generation. Preferably, signal information or the information content of the data in the signal is changed. Passive, on the other hand, means that the signal information remains unchanged. The signal is merely forwarded.

[0019] The use of a deflection device, particularly an RIS, offers the advantage of enabling effective implementation of terahertz communication in the IVN. It is irrelevant whether obstacles block the direct transmission path between transmitter and receiver, as the deflection device can create a new transmission path. This allows for reliable, in-vehicle radio transmission, particularly without signal interruptions.

[0020] In the present invention, the radio signal can, in particular, be a radio signal with highly directional electromagnetic waves. This means that it can be, for example, a mobile radio signal or another signal for wireless communication in a radio network. The deflection device can thus be used for wireless communication between the communication participants in the radio network. Examples of a transmitting and receiving device that can be communication participants in the radio network can be, for example, electronic control units (ECUs) in the on-board network of a motor vehicle. In the mobile radio sector, the communication participants can be, for example, a mobile terminal and / or a satellite and / or radio mast.

[0021] In this case, an RIS, i.e. the reflection matrix, is a component known per se for modifying a radio signal, as described above by way of example. In this case, modification can mean, for example, changing the direction of propagation or changing the beam shape of the radio signal. The modification can redirect or deflect the radio signal. In this case, redirection particularly means a change in direction. This means that the propagation direction of the radio signal can be changed using the RIS. By modifying, in addition to the configuration settings for redirection, further configuration settings for changing or modifying the propagation direction or the beam shape can be adjusted. In this case, redirection can include, for example, reflecting, absorbing, transmitting, splitting, collimating and / or focusing.In other words, redirection is achieved by adjusting the parameter, i.e., a property, of the radio signal using the reflective elements. This parameter can be, for example, a phase, an amplitude, a frequency, or a polarization of the radio signal. For example, applying Snell's law of refraction can convert a plane or planar electromagnetic wave, which forms the radio signal, into a scattered or directed wave. This is how beamforming, i.e., beam shaping, can be achieved using RIS.

[0022] The respective reflective element can also be understood as an electronic or electrical circuit that, depending on the wiring and design of the electronic components used, is capable of modifying the radio signal. The respective reflective element can thus be designed, for example, in the manner of an antenna. The respective configuration setting can, for example, specify an electrical property, such as an electrical resistance and / or an electrical capacitance and / or an impedance of the respective reflective element. To form a reflective element, for example, a so-called metamaterial can be used, preferably in the form of a so-called metasurface, as described above. The reflective elements are preferably preconfigured. This means that the configuration setting is static, i.e., cannot be changed or adjusted.

[0023] The individual reflective elements of the reflection matrix can each independently change one or more parameters of the radio signal to achieve the desired modification of the radio signal. Alternatively, several or all elements can have the same configuration setting, so that the radio signal is redirected in the same way.

[0024] The reflective elements can be arranged next to one another in a two-dimensional grid structure or a matrix to form the reflection matrix. Each reflective element can be designed as an electronic or electrical circuit that is exposed to the radio signal and can modify its parameters depending on the electrical properties specified by the configuration setting. As described above, a reflective element can, for example, be composed of an electromagnetic metasurface, in particular a cost-effective metallic metamaterial. Other components for a reflective element can be, for example, an intrinsic negative diode (PIN diode) and a dielectric substrate. The structure of an RIS is known per se from the prior art, for example from the publication by M. Di Renzo et al. (M. Di Renzo et al., “Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How It Works, State of Research, and the Road Ahead,” IEEE JSAC, vol. 38, no. 11, Nov. 2020, pp. 2450-2525.).

[0025] Preferably, the surface area of ​​each element is much larger, in particular 100 or 1,000 times larger than the wavelength of the radio signal, and the thickness of each element is much smaller than the wavelength of the radio signal. Preferably, the reflective elements are passive, meaning that no signal amplifiers are required.

[0026] Which deflection function is implemented by the RIS can be determined, for example, by adjusting the size of the reflective elements or their spacing from one another, the thickness, the type of metamaterial selected, and / or the selected configuration setting. For a RIS, the size of the reflective elements and their spacing from one another can, for example, correspond approximately to half the wavelength of the radio signal used. Feedback between the reflective elements can be neglected because there is sufficient spacing between the elements. Preferably, the reflective elements can each be arranged in a non-uniformly repeated pattern in the reflection matrix. In particular, the elements can have different geometric shapes and / or sizes, so that a desired functionality for deflecting the radio signal can be achieved with each of the elements.This type of RIS implementation is particularly cost-effective and passive, meaning it consumes essentially no energy. Furthermore, the RIS can operate with radio signals in the terahertz range, allowing for very high data rates.

[0027] Particularly preferably, the motor vehicle can comprise at least two, i.e., two or more, transmitting devices and / or at least two, i.e., two or more, receiving devices (receivers). In particular, the configuration setting of the respective RIS of the deflection device can be selected such that each transmitter is assigned to exactly one or more predetermined receivers. Conversely, each receiver can be assigned to exactly one or more predetermined receivers. The transmission channel for the radio signal in the radio network is determined or can be determined by the respective configuration setting of the respective RIS.

[0028] The transmitting device and the receiving device can, in particular, be devices capable of wireless communication. For this purpose, the transmitting device and the receiving device can, for example, have an antenna module for transmitting or receiving the respective radio signal. Examples of a transmitter and / or receiver can be a mobile terminal, virtual reality glasses, a camera, an electronic control unit (ECU), or another in-vehicle device designed for mobile communications or for wireless transmission to a radio network, such as a mobile communications network or WLAN network. Particularly preferably, the communication connection between the transmitter and the receiver can be bidirectional. This means that the transmitting and receiving devices can be designed as so-called transceivers, i.e., as transmitting and receiving devices.

[0029] In the present case, a motor vehicle preferably means a motor vehicle, in particular a passenger car or lorry or a passenger bus or motorcycle.

[0030] The invention includes embodiments which provide additional advantages.

[0031] According to one embodiment, the at least one transmitting device and the at least one receiving device are arranged at different positions in the motor vehicle. A direct transmission channel between the at least one transmitting device and the at least one receiving device is blocked. The at least one deflection device is then configured to provide a transmission channel between the respective transmitting device and the respective receiving device.

[0032] This means that at least one obstacle may be present in a transmission channel between the transmitting device and the receiving device, which completely or at least partially blocks the direct radio signal path, i.e., the direct radio signal. Blocking here refers in particular to attenuation, in particular complete or partial damping. The obstacle may, for example, be a vehicle component, such as a vehicle seat or a trim part or another vehicle interior component. Additionally or alternatively, the obstacle may, for example, be a passenger in the vehicle.

[0033] According to one embodiment, the at least one deflection device is arranged in the vehicle interior from a position that is visible to a passenger of the motor vehicle or hidden, i.e., concealed. This allows for various placement strategies for the deflection device.

[0034] In this context, one embodiment provides for the at least one deflection device to be arranged in (hidden) or on (visible) a vehicle seat, a vehicle roof, a vehicle door, a vehicle window, a trim part in the vehicle interior, or an underbody of the motor vehicle. "In" here means that the deflection device is integrated into a material of the respective component or is arranged or attached behind the respective component from the direction of the vehicle interior. "On" here means that the deflection device is attached or fastened, for example, to a surface of the respective component.

[0035] According to one embodiment, the motor vehicle comprises two or more deflection devices, each of which provides a different transmission channel for the radio signal between the at least one transmitting device and the at least one receiving device. In particular, different transmission paths for the radio signal transmission can thus be implemented. This is particularly advantageous in the automotive sector, since, for example, a transmission channel can regularly become blocked due to the movement of an occupant. The respective transmission channel assigned to the respective deflection device can, for example, be predetermined by the configuration settings or, alternatively, can be adjustable if the configuration settings are variable. The adjustability will be described in more detail later in connection with controllable RIS.

[0036] According to one embodiment, the motor vehicle comprises a control device configured to select at least one of the plurality of deflection devices for providing the transmission channel and to adjust a beam direction for the radio signal for the at least one transmitting device depending on the selected deflection device. This means that the control device can dynamically select the desired transmission channel for signal transmission.

[0037] For this purpose, the control device can test or verify the transmission channel in a verification routine. This involves checking whether the signal transmission via the respective transmission channel was successful. For example, the control device can evaluate the radio signal or a test signal according to a blocking criterion. The blocking criterion can indicate, for example, whether the respective transmission channel is currently blocked or whether the respective transmission channel is freely available for signal transmission. For this purpose, a response from the receiving device can be awaited and evaluated. Such methods for testing a connection are known per se.

[0038] To adjust the beam direction, the control device can, for example, control an antenna module of the transmitting device. The control can be carried out in such a way that the radio signal is radiated or directed in the desired direction, i.e., in the direction of the selected deflection device.

[0039] The control device can be designed, for example, as a control unit of the transmitting device. Alternatively, the control device can be, for example, a central control unit, such as a central on-board computer or an electronic control unit (ECU) of the motor vehicle.

[0040] The control device can comprise a data processing device or a processor device. For this purpose, the processor device can comprise at least one microprocessor and / or at least one microcontroller and / or at least one FPGA (Field Programmable Gate Array) and / or at least one DSP (Digital Signal Processor). Furthermore, the processor device can comprise program code configured to perform the desired function when executed by the processor device. The program code can be stored in a data memory of the processor device. The processor device can comprise, for example, at least one circuit board and / or at least one SoC (System on Chip).

[0041] The data storage may comprise at least one computer-readable storage medium. The storage medium may, for example, be provided at least partially as a non-volatile data storage device (e.g., as a flash memory and / or as an SSD - solid state drive) and / or at least partially as a volatile data storage device (e.g., as a RAM - random access memory). The storage medium may be arranged in the processor circuit in its data storage device. The program code may be provided as binary code or assembly code and / or as source code of a programming language (e.g., C) and / or as a program script (e.g., Python).

[0042] According to one embodiment, the deflection device comprises at least one sensor element and a control unit, also called a controller. At least one of the plurality of reflective elements comprises an electronically controllable control element. The sensor element is designed to detect at least one parameter of the incident radio signal. The control unit is designed to modify the respective configuration setting of the respective reflected element by controlling the control element, depending on the at least one detected parameter, and thereby adapt the at least one detected parameter. Thus, the plurality of reflective elements are designed to be controllable (rather than preconfigured). This allows an active instead of a passive RIS to be implemented. An active RIS is also referred to as an intelligent or smart RIS. The deflection properties of the RIS are thus dynamically adaptable.

[0043] A control element can be, for example, a PIN diode (Positive Intrinsic Negative Diode), a field-effect transistor, or a MIMS (Micro Electro Mechanical System), such as a single-chip system (System on a Chip) measuring just a few micrometers. The sensor element can be, for example, a conventional sensor for capturing and detecting radio signals. In this context, a control unit refers in particular to a data processing device or a processor. For this purpose, the processor can comprise at least one microprocessor and / or at least one microcontroller and / or at least one FPGA (Field Programmable Gate Array) and / or at least one DSP (Digital Signal Processor). To adapt the respective configuration setting, the control unit can, for example, adjust a control voltage of a PIN diode of the reflective element.For example, the electrical resistance of the reflective element can be changed. This makes it particularly easy to change the angle by which the incoming radio signal is deflected. The controllable control element can, for example, form a reflective element together with the metamaterial.

[0044] According to one embodiment, the radio signal has a frequency in a range between 300 GHz and 10 THz, in particular between 0.1 THz and 1 THz. Thus, terahertz radio communication with transmission rates of 1 Tbit / s or more can be achieved using the radio signal. The radio signal can, for example, comprise information and / or data for processing by the receiver. Depending on the data, the receiver can perform a predetermined function. The radio signal is therefore preferably a data signal.

[0045] According to one aspect, the invention relates to a communication system for forming a radio network for a motor vehicle, as described above. The communication system can, for example, be an in-vehicle network, as described above. The communication system comprises at least one transmitting device assigned to the motor vehicle and at least one receiving device assigned to the motor vehicle. By assigned here is meant that the respective device is preferably designed or arranged internally in the vehicle, as described above. The respective transmitting device and the respective receiving device are designed to be connected in the radio network. The respective transmitting device is designed to provide the radio signal for transmission to the at least one receiving device. The at least one receiving device is designed to receive the provided radio signal to perform a predetermined function.The communication system also comprises at least one deflection device assigned to the motor vehicle for deflecting the radio signal. The deflection device has at least one reflection matrix with a plurality of reflective elements. These form an intelligent reflective surface, i.e., an RIS, as described above. Each of the reflective elements is configured, in a manner known for a RIS, to modify at least one parameter of the incident radio signal, which was provided by the at least one transmitting device, according to a respective predetermined configuration setting and thereby redirect it to the at least one receiving device.

[0046] According to one aspect, the invention also relates to a method for operating a communication system as described above. In the method, in a setting routine, a transmission channel in the radio network for connecting the at least one transmitting device and the at least one receiving device is determined from a transmission channel table having at least two predetermined transmission channels by means of the at least one transmitting device and / or the at least one deflecting device. Subsequently, in an operating routine, the radio signal is provided or transmitted to the at least one receiving device via the determined transmission channel by means of the at least one transmitting device. The described method can be carried out, for example, by means of the aforementioned control device.The aim here is to determine the appropriate transmission channel for the radio signal and then to provide the radio signal via the determined transmission channel.

[0047] As previously described in connection with the control device, determining the appropriate transmission channel can, for example, involve checking the blocking criterion for the respective transmission channel. This can be done, for example, by waiting for a response signal from the respective receiving device after the radio signal has been transmitted. Additionally or alternatively, another known method for lossless data transmission between two instances, such as a so-called handshake, can be used to confirm or deny a blockage of the respective transmission channel.

[0048] For use cases or application situations that may arise during the method and which are not explicitly described here, it may be provided that, in accordance with the method, an error message and / or a request to enter user feedback is issued and / or a default setting and / or a predetermined initial state is set.

[0049] The invention also includes further developments of the communication system according to the invention and the method according to the invention, which have features already described in connection with the further developments of the motor vehicle according to the invention. For this reason, the corresponding further developments of the communication system according to the invention and the method according to the invention are not described again here.

[0050] The invention also encompasses combinations of the features of the described embodiments. The invention therefore also encompasses implementations that each comprise a combination of the features of several of the described embodiments, unless the embodiments are described as mutually exclusive.

[0051] Exemplary embodiments of the invention are described below. Shown are: Fig. 1 a schematic representation of a motor vehicle with a radio network for wireless data transmission using an intelligent reflective surface according to an embodiment, Fig. 2 a schematic representation of an interior of a motor vehicle with a radio network for wireless data transmission using an intelligent reflective surface according to a further embodiment Fig. 3 is a schematic representation of a reflection matrix forming an intelligent reflective surface according to an embodiment, and Fig. 4 a schematic process flow diagram for a method for operating a radio network for the motor vehicle.

[0052] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that can be considered independently of one another, each of which also develops the invention independently of one another. Therefore, the disclosure is intended to encompass combinations of the features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

[0053] In the figures, the same reference symbols designate elements with the same function.

[0054] In modern motor vehicles, the amount of data that needs to be exchanged between sensors, actuators, and various service functions in an in-vehicle network (IVN) has increased. Therefore, high-bit-rate communication links between participants are required to meet the requirements for low latency, security, and reliability in end-to-end communication. Future services, such as virtual reality (VR) applications, are envisioned as a key technology that will contribute to the advancement of human-machine interaction, where a user is present and interacts in a virtual world. VR as a service in a motor vehicle can revolutionize the design of instrument panels and the operation of control panels and the vehicle itself.At the same time, however, this technology will require very high bit rates for connections between an electronic control unit (ECU) and the VR equipment, such as VR glasses, for a user.

[0055] Today, high-speed connections with speeds of up to 10 Gbit / s are based on the well-known Ethernet technology, which uses shielded copper cables as the data transport medium. The use of wired vehicle networks can lead to limitations in the interior design of the vehicle. On the one hand, intelligent designs or arrangements are required for cables over 4 kilometers, whereby electromagnetic compatibility must be taken into account. On the other hand, the installation of such cables is complex and time-consuming, particularly with regard to the manufacturing and installation of the cables. The cables themselves can increase the weight of a vehicle by up to 60 kilograms and thus also increase the vehicle's energy consumption. At the same time, the cables themselves are usually difficult to access, which means that repairs are limited or very complex, for example in the event of a cable breakage as a result of an accident.In addition, electromagnetic interference leads to signal distortion and data loss and can therefore reduce the transmission speed of wired communication connections.

[0056] The challenge is to achieve high data rates without increasing the number of cables, cable length, vehicle weight, cost, or complexity of the vehicle's wiring. This can be achieved, for example, with ultra-high-speed wireless connections integrated into the vehicle network. The terahertz frequency band is currently one of the most promising communication technologies for using high data rates and low latency in communication with data rates of up to 1 Tbit / s. However, radio signals in the terahertz range, i.e., with a frequency in the range between 300 gigahertz and 10 terahertz, can easily be attenuated, for example, by obstacles.When used in a motor vehicle, such obstacles can be, for example, interior components such as a vehicle seat, a trim panel, or another interior component, or they can be caused by an occupant or driver of the vehicle itself. Moving obstacles in particular can make it impossible, or at least temporarily unavailable, for a direct transmission channel or transmission path for the radio signal between two participants in the radio network.

[0057] Therefore, it may be useful to dynamically provide alternative transmission channels for the radio signal in the in-vehicle network. For this purpose, the use of reconfigurable intelligent surfaces (RIS), also called intelligent reflective surfaces (IRS), is proposed. Such RIS consist of a large number of low-cost, adaptive and passive reflective plates or surfaces made of a thin composite material and are capable of passive beamforming in a predefined and controllable manner. RIS can thus increase the coverage of wireless communication systems, particularly for high data rates of terahertz communication, while simultaneously reducing interference between the participants in the communication system.

[0058] Fig. Figure 1 shows an example of how a RIS can be used in a vehicle network, particularly an in-vehicle radio network. Fig. 1 a motor vehicle 1, in particular a passenger car, is shown schematically from a top view in a sectional view. The motor vehicle 1, also referred to below as vehicle, is for example a passenger car. The motor vehicle 1 comprises a vehicle network which is designed as an internal vehicle radio network N. The radio network N can also be referred to as a communication system S. By means of the radio network N, a cable-free or wireless data transmission or radio communication between its participants can be implemented. The radio network N should be designed for terahertz communication. This means that radio signals with frequencies in the terahertz range should be able to be transmitted for data transmission. To enable terahertz communication, the participants in the radio network N can be equipped with corresponding antenna modules, for example for generating, transmitting, receiving and processing a corresponding radio signal.Such antenna modules for terahertz communication, also known as 6G communication, are well known.

[0059] As participants or peripheral devices in the radio network N are Fig. 1 shows, by way of example, five electronic control units 30, also abbreviated to ECUs below. One of the ECUs 30 is designed, for example, as a central control unit 31 (central ECU). This can be, for example, a central on-board computer of the motor vehicle 1. The remaining ECUs 30 are, for example, zone control units (zonal ECUs) or zone ECUs 32. The zone control units 32 are control units that are each used for exactly one zone, i.e., one area, in the motor vehicle 1 for monitoring and evaluating sensor data assigned to that area.

[0060] In the present exemplary embodiment, the motor vehicle 1 is divided into four zones, namely front right, front left, rear right, and rear left (with respect to a direction of travel of the motor vehicle). One or more vehicle sensors 33 and / or vehicle actuators 34 are assigned to each zone, for example. Each of the zone ECUs 32 is responsible for the respective vehicle sensors 33 and vehicle actuators 34 assigned to the zone. This means that the zone control unit 32 can, for example, acquire and evaluate sensor data from the sensors 33 and, for example, provide control data for controlling the actuators 34. Typical sensors or actuators 33, 34 in the vehicle area can be, for example, a camera, a lighting system, an infotainment system, a seat adjuster, a locking system, an air conditioning system, or another known electronically controllable vehicle system.

[0061] Such a network architecture with the division into zones is used in a known manner to optimize the computing power in the vehicle for data processing, for example, of sensor data. In this case, data preprocessing is carried out using the zone control units 32, for example, while the central control unit 31 handles the postprocessing and / or central monitoring for the vehicle network. For this purpose, the ECUs 30 are interconnected via a communication link so that, for example, signals can be transmitted from the respective zone control unit 32 to the central control unit 31 and vice versa. This means that the participants in the radio network N can be used as transceivers, i.e., as transmitters and receivers or transmitting and receiving devices for transmitting and receiving signals.In this way, computing power can be outsourced from the central control unit 31 to the zone control units 32, thereby optimizing overall computing operations and improving signal transmission.

[0062] In previous vehicles, the ECUs 30 were connected to each other via Ethernet cables to enable high-bit-rate communication. Data or signal transmission thus occurred via a cable or wired connection via the respective Ethernet cable, which provided an Ethernet transmission channel E. In the figures, the Ethernet transmission channel E is shown as an example in dashed lines and connects the ECUs 30 directly or immediately to each other.

[0063] To reduce the cabling effort, as mentioned above, radio communication with radio signals in the terahertz range is used. To enable undisturbed radio transmission between the ECUs 30, the RIS mentioned above are used. In the present exemplary embodiment, the RIS are implemented or realized as a reflection matrix 10 in a deflection device 20. The reflection matrix 10 comprises a plurality of reflective elements. Each of the reflective elements is designed to modify at least one parameter of an incident radio signal according to its respective predetermined configuration setting and thereby deflect it. The respective deflection device 20 can thus implement a deflection function or deflection function for the respective radio signal by using the RIS. How the respective deflection device 20 can be specifically constructed and its function will be explained later with reference to Fig. 3 described in more detail.

[0064] In the embodiment in Fig. 1, a plurality of deflection devices 20 are installed at different positions in the vehicle interior, for example, in a driver's cab. The positioning and number of the deflection devices 20 are selected such that different transmission channels K are available between the ECUs 30 for radio signal transmission. This means that the respective ECU 30 can be connected via one or more deflection devices 20 to a different ECU 30 in the radio network N. Examples of different transmission channels K are shown in Fig. 1 and Fig. 2 by the arrows between the deflection devices 20 and the ECUs 30.

[0065] At this point, it should be noted that the figures only show one possible positioning for the deflection devices 20. The number of deflection devices 20 used and their positioning depends heavily on the positioning of the transmitters and receivers, in this case the ECUs 30, in the radio network N. Further boundary conditions for the number and placement of the deflection devices 20 can, for example, be obstacles in the vehicle interior or the required reliability level of the terahertz connections between the participants. A different arrangement of the ECUs 30 in the embodiment in Fig. 1 would therefore result in a different positioning and a different number of deflection devices 20 to enable high-speed terahertz connections between the ECUs 30.

[0066] The deflection devices 20 can have different geometric shapes and / or different sizes. They can be mounted either hidden or visible to the occupant in or on components in the vehicle interior. For example, deflection devices 20 can be mounted in or on surfaces of vehicle components or, for example, installed in the cavities previously used for Ethernet cable routing. Fig. 1 and Fig. 2 shows embodiments in which the deflection devices can be installed, for example, in the vehicle seat 2, a vehicle roof, a door panel 6 or under the underbody 4 or other paneling parts in the vehicle interior.

[0067] Fig. 2 shows another example of a radio network N analogous to the embodiment in Fig. 1. The radio network N includes, for example, two VR glasses 8 as additional participants, which a respective occupant can use for a VR experience in the motor vehicle 1. Fig. 2 shows the vehicle interior I as an example from a front view, for example from a direction of travel. According to the embodiment in Fig. Figure 2 again shows a zone network architecture with the four zone control units 32 and the central control unit 31. The ECUs 30 are installed, for example, in the underbody 4 of the motor vehicle 1. Several deflection devices 20 are located in the underbody to create a hidden transmission channel K between the ECUs 30. Further deflection devices 20 are installed, for example, on the sides of the door panels 6, on the vehicle seat 2, and on a vehicle roof 3. The deflection devices 20 are attached to the respective surface of the vehicle component, visible to the occupant, for example. In this way, visible or superficial transmission channels K or transmission paths can be realized, for example, for data transmission or communication between the ECUs 30 and the respective VR headset 8.

[0068] In Fig. Figure 3 shows an example of a deflection device 20 with a reflection matrix 10 configured as an RIS. RIS is a known technology by which electromagnetic waves can be modified to change their propagation direction and, for example, a beam shape. Fig. Figure 3 shows a schematic representation of an exemplary embodiment for the structure of such a reflection matrix 10. The RIS comprises a plurality of reflective elements 11. In the present exemplary embodiment, twelve such reflective elements 11 are shown as an example. Depending on the desired area of ​​application of the RIS, more or fewer reflective elements 11 can of course be provided. The reflective elements 11 are arranged in a two-dimensional grid structure in a plane relative to one another. Each of the reflective elements 11 has a thickness that is less than the wavelength of the radio signal F. The resulting reflection matrix 10 can thus have an overall thickness that is much less than the wavelength of the radio signal F, but whose surface area can be up to 10 or 1000 times larger than the wavelength of the radio signal F.

[0069] Each of the reflective elements 11 is designed to modify at least one parameter of an incident radio signal F, which was provided by the respective transmitting device, according to its respective predetermined configuration setting and thereby redirect it to at least one receiving device. Modifiable parameters of the radio signal F include, for example, a phase, amplitude, frequency, and / or polarization of the radio signal F. Thus, for example, by modifying the phase of the incident wavefront of the radio signal, it can be converted from a plane wave into a scattered wave, the phase shift of which is adjusted such that the desired reflection or redirection is achieved. Depending on the selected configuration setting for the respective reflective element, the radio signal F can be modified by means of the RIS, for example, so that it is reflected, absorbed, transmitted, split, collimated, and / or focused.

[0070] To implement this type of modification, the respective RIS is designed as a so-called metasurface. The reflective elements 11 are then also referred to as metaatoms. Each of the elements 11 can form an electronic circuit, for example in the manner of an antenna. To form a reflective element, for example, a cost-effective metallic metamaterial 11b can be applied to a dielectric substrate 11a. The metamaterial is processed in such a way that the electrical properties, i.e. the desired configuration settings, such as a resistance and / or an electrical capacitance for the deflection function of the respective element 11, can be introduced or simulated. The reflective elements 11 are preferably preconfigured. This means that the configuration settings are unchangeable. This makes it possible to produce a passive RIS.Such RIS have the advantage that they do not require an additional power supply.

[0071] In the embodiment in Fig. In comparison, Figure 3 shows an active RIS. Active in this context means that the configuration settings are adaptable or modifiable. For this purpose, each of the reflective elements comprises an electronically controllable control element 11c. In the present embodiment, the control element is, for example, a PIN diode. By adjusting the control voltage for the PIN diode, an electrical resistance of the respective reflective element 11 can be changed, thus changing the configuration settings and thus the deflection properties, such as the propagation direction or the angle at which the radio signal F is deflected.

[0072] In order to be able to dynamically adapt the deflection properties, the reflection matrix 10 according to the embodiment in Fig. 3 also a control unit 12 and a respective sensor element 13 for each of the reflective elements 11. By means of the sensor element 13, at least one parameter of the incident radio signal F can be detected. This means that the properties of the radio signal F, such as the frequency, are thereby known. By means of the control unit 12, the parameter can be evaluated and, depending on the parameter, the respective configuration setting of the associated reflective element 11 can be modified by controlling the control element 11c. As a result, the detected parameter of the radio signal F can be adjusted and thus the radio signal F can be redirected in the desired manner. The control unit 12 can be, for example, a microcontroller or microprocessor. According to the embodiment in Fig. 3, for example, a control unit 12 is provided for the reflection matrix 10. Of course, one of the ECUs, in particular the domain ECU 31, can be used to operate multiple RIS 10 and / or the deflection device 20.

[0073] In addition to controlling the control element 11c or adjusting the meta-material 11b, for example, the size, the distance or a thickness of the respective reflective element 11 can be adjusted in order to achieve the desired deflection function with the RIS.

[0074] As in Fig. 3, the reflection matrix 10 is present in a two-dimensional basic form. For this purpose, the reflective elements are applied to a two-dimensional base body 14 or substrate in the described lattice structure. The base body 14 can, for example, be a film or plate whose thickness is much less than its length or width. The base body 14 can be made of any material with the properties suitable for attachment or positioning in the desired environment. For example, a transparent substrate can be selected for attaching the reflection matrix 10 to a window in the motor vehicle 1. Alternatively, an adhesive film with a self-adhesive surface can be selected, for example, to fix the reflection matrix in the desired position.Another example of a substrate is a printed circuit board, in particular a flexible or bendable printed circuit board, into which, for example, the cabling between the reflective elements 11 and the control unit 12 and / or the sensor elements 13, as well as their fastening, can be implemented. The base body 14, together with the reflection matrix 10, forms the reflective elements, as well as, in the exemplary embodiment in . Fig. 3 the sensor elements 13 and the control unit 12 the deflection device 20.

[0075] Fig. 4 now shows an exemplary process flow diagram for a method for operating a communication system S, i.e. a radio network N, as is shown for example in Fig. 1 and Fig. 2. In the following, Fig. 4 will now explain how terahertz connections between the RIS, i.e., the deflection devices 20, and end-to-end connections between the ECUs 30 can be established. The operating modes of the deflection devices can be classified or divided into two phases, which can be performed, for example, once at vehicle start-up or periodically to take into account the dynamic environment in the vehicle interior, particularly with regard to obstacles. The first phase can be referred to as the control phase. In the control phase, for example, a setting routine can be performed. The setting routine is described in step S1 of the Fig. 4 is shown as an example. In this case, a transmission channel K in the radio network N for connecting the respective subscribers is determined from a transmission channel table with at least two predetermined transmission channels. This means that an unblocked path for signal transmission can be selected from the multitude of available transmission channels. The aim of this phase is therefore to reconfigure the transmitters, in particular the transmitters and receivers, and the deflection devices in the system based on a change in the environment of the vehicle interior. This can happen, for example, when a driver or passenger moves, a new object is brought into the vehicle, or a vehicle component such as the vehicle seat 2 or a window is moved.The setting routine can be carried out, for example, every time the vehicle is restarted or during operation of the vehicle, for example whenever a current transmission channel between two participants is blocked.

[0076] In the case of a completely passive RIS, i.e., an RIS without a control unit, the respective RIS can be preconfigured, in particular the respective reflective element can be preconfigured, to realize predefined reflections in the vehicle interior, thus creating a set of alternative transmission paths. The transmission channels are precalculated and can be stored, for example, on the transmitter side, i.e., in the respective ECU 30. Preferably, all transmission channels K can be sorted from shortest to longest. The shortest path can, for example, represent the direct terahertz connection between the origin and destination of the radio signal. The remaining paths represent transmission channels for which the reflections are selected by means of the RIS to establish the connection between transmitter and receiver.For example, if the transmitter of a radio signal detects that a path is blocked, another path is selected. For example, the angle of departure of the transmitter, particularly an antenna module of the transmitter, can be adjusted for transmitting the radio signal so that the selected path is used for signal transmission.

[0077] This means that in passive redirection devices, the control logic for transmission channel selection can be implemented by the respective message transmitter, for example, by the ECUs 30. For this purpose, each of the ECUs 30, which are configured as transmitters in this case, can include corresponding control logic.

[0078] If, however, controllable deflection devices 20 are used, the deflection devices 20, such as in Fig. 3, can themselves be equipped with the sensor elements 13. These sensor elements 13 can, for example, be designed to send and receive control messages from a central control system, such as the central control unit 31, in the motor vehicle 1, or can themselves estimate the transmission channel status. The reflective elements 11 of the respective deflection device 20 can thus be controlled by the integrated control unit 12, by means of which, for example, the PIN diode 11c can be adjusted so that each of the reflective elements can adjust the rotation phase, i.e., the deflection of the incoming wavefront. The path monitoring and selection of the respective transmission channel can thus be implemented by the respective deflection device itself.

[0079] The second phase is also called the operational phase or operating phase. In the process flow diagram in Fig.4, the operating phase is symbolized in step S2. During the operating phase, an operating routine can be performed in which the radio signal is provided or transmitted from the respective transmitter to the respective receiver via the transmitted transmission channel. This means that the deflection devices 20 are now configured and ready to support terahertz transmission from various transmitters, in this case the zone control units 32 and the central control unit 31. When the operating phase begins, data can thus be transmitted between the source and destination via the respective deflection device 20 in the vehicle's internal radio network N.

[0080] Overall, the embodiments show a terahertz in-vehicle network based on reconfigurable intelligent surfaces. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 2021 / 0195669 A1

[0004] US 2022 / 0123803 A1

[0013] US 2021 / 0126359 A1

[0014] Cited non-patent literature

[0000] M. Di Renzo et al., "Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How It Works, State of Research, and the Road Ahead," IEEE JSAC, vol. 38, no. 11, Nov. 2020, pp. 2450-2525

[0024]

Claims

[1] Motor vehicle (1) with a radio network (N) for transmitting a radio signal within the vehicle, wherein the motor vehicle (1) comprises at least one transmitting device within the vehicle and at least one receiving device within the vehicle, which are designed to be connected to one another in the radio network (N), wherein the at least one transmitting device is designed to provide the radio signal for transmission to the at least one receiving device, and the at least one receiving device is designed to receive the provided radio signal for performing a predetermined function, characterized byin that the motor vehicle (1) comprises at least one deflection device (20) for deflecting the radio signal, wherein the deflection device (20) comprises at least one reflection matrix (10) with a plurality of reflective elements (11) which form an intelligent reflective surface, wherein each of the reflective elements (11) is designed to modify at least one parameter of the incident radio signal, which was provided by the at least one transmitting device, according to its respective predetermined configuration setting and thereby to deflect it to the at least one receiving device. [2] Motor vehicle (1) according to claim 1, wherein the at least one transmitting device and the at least one receiving device are arranged at different positions in the motor vehicle (1), wherein a direct transmission channel (K) between the at least one transmitting device and the at least one receiving device is blocked. [3] Motor vehicle (1) according to one of the preceding claims, wherein the at least one deflection device (20) is arranged in the vehicle interior (I) from at least one position so as to be visible or hidden for an occupant of the motor vehicle (1). [4] Motor vehicle (1) according to claim 3, wherein the at least one deflection device (20) is arranged in or on a vehicle seat (2), a vehicle roof (3), a vehicle door, a vehicle window, a trim part in the vehicle interior, or an underbody (4) of the motor vehicle (1). [5] Motor vehicle (1) according to one of the preceding claims, wherein the motor vehicle (1) comprises two or more deflection devices (20) which each provide a different transmission channel (K) for the radio signal between the at least one transmitting device and the at least one receiving device. [6] Motor vehicle (1) according to claim 5, wherein the motor vehicle (1) comprises a control device which is designed to select at least one of the deflection devices (20) for providing the transmission channel (K) and to set a beam direction for the radio signal for the at least one transmitting device depending on the selected deflection device (20). [7] Motor vehicle (1) according to one of the preceding claims, wherein the deflection device (20) comprises at least one sensor element (13) and a control unit (12), wherein the sensor element (13) is designed to detect at least one parameter of the incident radio signal, and the control unit (12) is designed to modify the respective configuration setting of the reflective element (11) as a function of the at least one detected parameter and to adapt the at least one detected parameter. [8] Motor vehicle (1) according to one of the preceding claims, wherein the radio signal has a frequency in a range between 300 GHz and 10 THz, in particular between 0.1 THz and 1 THz. [9] Communication system for forming a radio network (N) for a motor vehicle (1) according to one of the preceding claims, wherein the communication system (S) comprises at least one transmitting device assigned to the motor vehicle (1) and at least one receiving device assigned to the motor vehicle (1), which are designed to connect in the radio network (N), wherein the at least one transmitting device is designed to provide the radio signal for transmission to the at least one receiving device, and the at least one receiving device is designed to receive the provided radio signal for performing a predetermined function, characterized byin that the communication system (S) comprises at least one deflection device (20) assigned to the motor vehicle (1) for deflecting the radio signal, wherein the deflection device (20) comprises at least one reflection matrix (10) with a plurality of reflective elements (11) which form an intelligent reflective surface, wherein each of the reflective elements (11) is designed to modify at least one parameter of the incident radio signal, which was provided by the at least one transmitting device, in accordance with its respective predetermined configuration setting and thereby to deflect it to the at least one receiving device. [10] Method for operating a communication system (S) according to claim 9, wherein in a setting routine by means of the at least one transmitting device and / or the at least one deflection device a transmission channel (K) in the radio network (N) for connecting the at least one transmitting device and the at least one receiving device is determined from a transmission channel table with at least two predetermined transmission channels (K), and in an operating routine by means of the at least one transmitting device the radio signal is provided to the at least one receiving device via the determined transmission channel (K).

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