Radar sensor device for a vehicle, radar system having a radar sensor device and vehicle having a radar system

Abstract

The invention relates to a radar sensor device (3) for a vehicle (1), having an optical input opening (8) for receiving an optical transmission signal (6), a transmitting device (13) for emitting an electrical radar emission signal (15) based on the optical transmission signal (6) into the surroundings (17) of the vehicle (1), a receiving device (14) for receiving an electrical reception signal (16) corresponding to the electrical radar emission signal (15) and reflected in the surroundings (17), and characterized by at least one antenna structure (18) having two oppositely arranged and spaced apart metal structure elements (19, 20), wherein the at least one antenna structure (18) is configured to generate the electrical radar emission signal (15) and to modulate the received electrical reception signal (16) in dependence on the metal structure elements (19, 20). Furthermore, the invention relates to a radar system (2) and to a vehicle (1).

Description

Technical Field

[0001] This invention relates to a radar sensor device for a vehicle, having an optical input port for receiving optical transmission signals. Furthermore, the radar sensor device includes a transmitting device for transmitting an electrical radar signal based on the optical transmission signals into the vehicle's surrounding environment. Additionally, the radar sensor device includes a receiving device for receiving an electrical received signal corresponding to the electrical radar signal and reflected in the surrounding environment.

[0002] Furthermore, the present invention relates to a radar system having at least one radar sensor device and a central electronic computing device. Similarly, the present invention relates to a vehicle having a radar system. Background Technology

[0003] WO 2017 / 189 863A1 discloses an optical device comprising at least two waveguides with different propagation constants. Each waveguide is associated with a lattice antenna having a lattice period, the lattice antenna being constructed such that it emits constant light with the same emission angle despite the different propagations. Each waveguide may be part of an optical path containing a phase shifter.

[0004] Furthermore, WO 2018 / 160 729A2 discloses a three-dimensional optical inspection system for vehicles. Here, electromagnetic radiation can be transmitted to an optical signal processing module, which includes a photonic integrated circuit capable of generating one or more signals with customized amplitude, phase, and spectral characteristics. Multiple optical signals processed by the optical signal processing module can be sent to radiation control units distributed around the vehicle.

[0005] A terahertz device is known from WO 2018 / 172 302A1, which includes a first waveguide, the first waveguide being a plasma waveguide. The terahertz device may have an antenna with a first arm and a second arm. Summary of the Invention

[0006] The purpose of this invention is to provide a radar or radar system that can be used for more compact and efficient environmental detection in vehicles.

[0007] This objective is achieved by a radar sensor device, radar system, and vehicle according to the present invention.

[0008] One aspect of the present invention relates to a radar sensor device for a vehicle, comprising:

[0009] - Optical input port, which is used to receive optical transmission signals;

[0010] - A transmitting device for transmitting signals from an electrical radar based on optical transmission signals into the vehicle's surrounding environment;

[0011] - A receiving device, the receiving device being used to receive an electrical received signal corresponding to a signal emitted by an electrical radar and reflected in the surrounding environment; the radar sensor device having:

[0012] - At least one antenna structure having two opposing and spaced-apart metallic structural elements, wherein,

[0013] - At least one antenna structure is configured to generate electrical radar signals and modulate received electrical signals based on metallic structural elements.

[0014] The radar sensor device according to the invention provides a more compact radar or radar system for vehicles, wherein power requirements can be reduced. In particular, the radar sensor device has a smaller structural space or space requirement, making it more space-efficient for use in radar systems within vehicles.

[0015] For example, the radar sensor device according to the invention allows the use of a standard long-range communication laser. In particular, this eliminates the need for costly and expensive gigahertz circuit design for frequency conversion between radio frequency signals and optical carriers. This is especially true after conversion from the terahertz spectrum, where the gigahertz signal is stabilized. Consequently, a reduction in chip area can be achieved compared to conventional electronic devices. The conversion device, for example, replaces the Epic chip. In particular, the ring circuit can be implemented very simply, where the high quality factor of the optical ring resonator determines the low power requirement of the laser, allowing coupling losses to be compensated, and multiple chips can operate using a single source. In particular, the gigahertz signal is inherently stable. In particular, a low-noise signal can be provided. The SNR (“signal-to-noise ratio”) can be improved by means of the conversion device. In particular, the radar sensor device according to the invention is more sensitive to polarization. Furthermore, the radar sensor device according to the invention requires less power and, in particular, less structural space.

[0016] In particular, the transmitting and receiving devices can be integrated on a single semiconductor chip, such as in CMOS, SiM-CMOS, Bi-CMOS, Hybrid-Bi-CMOS, or via a process that integrates them on a photonics-electronics co-integrated chip. Therefore, with the aid of this invention, radar sensor devices can be manufactured in mass production, for example, using standardized semiconductor processes.

[0017] In particular, the transformation device according to the invention allows for better realization of loop circuits for connecting multiple photonic semiconductor chips using optical fibers. Currently, microwave transmission belt systems are used to achieve high-resolution radar systems in the automotive field. These microwave transmission belt systems result in 3D conductor structures for radiation in the mm wavelength range, which require additional three-dimensional structural space. This can be improved by the radar sensor device according to the invention. The transformation device reduces the limitations on the detectable spectrum range due to antenna geometry.

[0018] In particular, by means of the radar sensor device according to the invention, frequency conversion of the terahertz carrier signal in the gigahertz frequency range can be performed after optical signal transmission, and conversely, reception of the gigahertz signal and modulation onto the terahertz carrier signal can be performed.

[0019] The radar sensor device according to the invention enables the co-integration of a ring resonator in a semiconductor as an antenna structure and for frequency conversion using photonics-electronics. In particular, the proposed radar sensor device can be used in motor vehicles. Specifically, it can be used in, for example, at least partially autonomous motor vehicles, and especially in fully autonomous motor vehicles. For such autonomous driving, reliable environmental perception is essential, which can be achieved through the radar sensor device according to the invention. Here, the environment or surrounding environment can be detected by means of sensors such as radar, lidar, and cameras. This can be an example of the application areas of the radar sensor device. A comprehensive 360-degree three-dimensional detection of the surrounding environment can be performed using the radar sensor device, thereby detecting all static and dynamic objects.

[0020] Radar sensor devices can be used as alternatives to lidar, especially lidar, which plays an important role in redundant and robust environmental detection because this type of sensor can more accurately measure distances and angles in environmental detection and can also be used for classification.

[0021] In particular, radar sensor devices can be used in, for example, at least partially autonomous vehicles, but especially in fully autonomous vehicles. However, reliable environmental perception is essential for achieving such autonomous driving. Here, the environment or surroundings can be detected using sensors such as radar, lidar, and cameras. Of particular importance is the overall 360-degree three-dimensional detection of the surrounding environment, enabling the detection of all static and dynamic objects. Radar sensor devices can be used for this purpose. LiDAR, in particular, plays a crucial role in redundant and robust environmental detection because this sensor type can measure distances more accurately in environmental detection and can also be used for classification. However, these lidar sensors are costly and expensive in their construction. In particular, 360-degree three-dimensional environmental detection is problematic because ensuring this requires either many small individual sensors, typically working with many individual light source and detector elements, or the installation of large lidar sensors. Furthermore, lidar sensors are easily affected by weather conditions such as rain, fog, or direct sunlight. Radar sensor devices can provide remedies for this.

[0022] Radar sensors or radar sensor devices have been established in automotive engineering and provide data reliably and without failure in all weather conditions. Even poor visibility (such as rain, fog, snow, dust, or darkness) hardly affects their perception reliability. However, according to the prior art, resolution has been quite limited to date; in particular, existing radar systems are only constructed with an angular resolution of about 7 degrees. To meet the requirements of increased automation and safer driving functions in automotive engineering, radar sensor devices are configured to provide three-dimensional images with fine angular resolution in the range of 0.1 degrees and below, and with greater insensitivity to interference from their surrounding environment. This cannot be achieved using conventional radar technology according to the prior art because the resolution of such systems is too coarse. The radar sensor device according to the invention advantageously addresses this issue.

[0023] The radar sensor device can be configured as a photonic radar sensor device, which improves resolution by co-integrating electronic and photonic components onto a single semiconductor chip. Tracking of the FMCW signal, as well as the entire signal processing and evaluation, is performed at a central station. Each transmit and receive module has an electronically and photonically integrated chip, the so-called Epic chip. For this co-integration, silicon-photonics technology is used. This silicon-photonics technology enables the overall integration of photonic structural elements, high-frequency electronic devices, and digital electronic devices onto a single chip. The technological innovation of such a system lies in the use of optical carrier signals in the terahertz frequency range for gigahertz signal transmission. The central station (which can also be called a central electronic computing device) generates the terahertz optical carrier frequency. The transmitted signal, carrying one-eighth of the radar frequency, is modulated onto this optical carrier frequency and sent to antenna chips via optical fibers. An eightfold frequency multiplication occurs on these antenna chips, allowing radar radiation to be emitted by the antenna chips. Signal detection is performed in reverse order. All data is processed at the central station.

[0024] However, such implementations are very costly in terms of chip-level implementation of gigahertz electronics. In particular, the frequency multiplication performed on the chip after detection by photodiodes is technically challenging and poses a significant challenge in generating gigahertz signals with high signal-to-noise ratios and minimal jitter. Therefore, the gigahertz signal must be costly stabilized in additional steps. Furthermore, gigahertz electronics are expensive. In addition, high power requirements are placed on the optical carrier, especially the laser, as a large amount of optical power is needed to generate high-precision gigahertz signals, making it difficult to implement a loop circuit with a unique phase for radar arrays with many distributed radar semiconductor chips. In particular, two additional photonics-electronics semiconductor chips are required for the corresponding transmit and receive channels, leading to further cost increases. The radar sensor device according to the invention at least partially, and especially completely, solves the aforementioned problems.

[0025] This invention particularly utilizes radiation from a laser device (which can also be configured as a CW laser) coupled into a photonic semiconductor via an optical interface. Here, it can be an optical transmission signal or a carrier signal from the CW laser. The radiation propagates within a linear waveguide structure situated within the semiconductor. This semiconductor can be, for example, a radar sensor device or a semiconductor chip on which a radar sensor device is integrated.

[0026] For example, a radar sensor device may have one or more integrated circuits (ICs). For instance, all components of a radar sensor device may be integrated onto a single chip. Additionally, for example, a transmitting device may be constructed as an integrated circuit or chip, and a receiving device may be constructed as an integrated circuit or chip.

[0027] In particular, the radar sensor device according to the invention can be used in electromagnetic or optical applications.

[0028] Optical transmission signals can be generated using laser devices, particularly CW lasers. These optical transmission signals can then be used to generate or modulate signals emitted by electrical radar. These radar signals can be emitted into the vehicle's surrounding environment using a transmitting device, transmitting unit, or transmitting module of a radar sensor device. The emitted signals can be reflected by objects in the vehicle's surrounding environment, for example. These reflections can be received or detected using a receiving device or receiving module. For example, a radar sensor device can have multiple receiving channels and / or transmitting channels.

[0029] In particular, the antenna structure can be a plasma structure or a plasma antenna structure. Such a plasma structure may have an integrated waveguide. The optical carrier signal, especially the optical transmission signal, can be coupled into the carrier substrate (e.g., a semiconductor chip or optical substrate) via a photonic interface or a grid coupler, especially an optical input port. Light, waves, or radiation propagate through the gap between the two metallic structural elements. If the gap between the structural elements is small enough and, for example, resonant motion is satisfied, such as the fundamental resonance condition or higher harmonic resonance conditions, then a time-dependent charge shift can be induced by the evanescent field of the optical carrier. This charge shift can drive plasma resonance, which, for example, is electrically measurable, provided the spacing between the two structural elements is properly chosen. Therefore, any time-modulated optical signal can be transmitted to the antenna or antenna structure, corresponding to a frequency conversion, for example, from the gigahertz frequency range to the terahertz frequency range, or vice versa.

[0030] If an external electromagnetic field, particularly an electrical receiving signal, encounters structural components, this induces time-varying charge separation between the components. This results in modulation of the refractive index of the optical transmission signal within the waveguide in which it is coupled, causing the optical carrier signal to be time-modulated and containing at least one characteristic of the external field, namely radar information. This radar information can be evaluated for vehicle environmental detection.

[0031] Therefore, by means of an antenna structure, modulation of electromagnetic radiation propagating in a waveguide can be performed using plasma resonance. This can be used not only for transmission but also for reception. For example, optical waveguides can be arranged between structural elements so that light can be modulated within these waveguides.

[0032] Passive modulation is achieved using the antenna structure according to the invention. This is achieved through plasma resonance, particularly by modulating the refractive index of the waveguide into which the optical transmission signal is coupled. Specifically, plasma resonance and, in particular, field elevation can be utilized for both the generation of signals emitted by electrical radar and the modulation of received electrical signals. Or field elevation effect. For this purpose, frequency conversion between optical signals and gigahertz or terahertz signals can be performed using plasma resonance. For this purpose, the combination of antenna and frequency converter can be carried out, particularly in a component preferably based on semiconductor, using the antenna structure according to the invention. Therefore, optical conversion antennas can be used for environmental detection in vehicles. This can be used not only for radar sensors but also for lidar sensors.

[0033] Plasma is a quantized fluctuation of charge carrier density in a solid. In quantum mechanics, it is considered a boson quasi-particle. For example, in the case of plasma, distinctions are made between particulate plasma, surface plasma, and volumetric plasma. As plasma, one can imagine the vibration of electrons oscillating relative to positive ions. If this free electron is compressed in a localized region, a Coulomb force attempting to restore a uniform charge distribution acts on the electron. Due to its inertia, the electron is ejected at a neutral position and builds up a new charge excess, thus producing periodic vibrations. The circular frequency of the electron density oscillation around the average density is called the plasma frequency. Furthermore, plasma oscillations can also be formed, which require periodic oscillations of charge density in a medium (e.g., plasma or metal). The quasi-particles produced by the quantization of these oscillations can be called plasma.

[0034] Plasmon resonance should be understood as the longitudinal vibration of an electron-dense metal, which can be called plasma vibration. The excitation of this vibration is called plasma resonance. In particular, plasma resonance is a nano-optical effect. Plasma consists of quasi-particles composed of many electrons that appear and vibrate back and forth in the case of other metals. If, for example, special light is radiated onto a nanopillar, the light can interact with the plasma in the gold or other metals. Here, the light is partially absorbed, which can thus be called plasma resonance.

[0035] For example, electromagnetic radiation can be detected by means of a photonic antenna using a radar sensor device according to the invention. For this purpose, photonic-electronic co-integration of a photonic antenna, for example, in a semiconductor, can be used as a frequency converter.

[0036] For example, the antenna structure can be used as a receiving antenna and / or a transmitting antenna. For this purpose, the metallic structural elements can be constructed, for example, as metallic nanostructures or microstructures.

[0037] For example, metallic structural components may contain at least a proportionate portion, and especially entirely, aluminum, copper, or gold. In particular, the material of metallic structural components should have good electromagnetic properties, and especially good dielectric properties.

[0038] In particular, the antenna structure can be used to convert received gigahertz or terahertz signals into optical signals.

[0039] For example, the antenna structure can be a dielectric, photonic antenna element or an antenna.

[0040] In one embodiment of the invention, two metallic structural elements are configured to have a predetermined spacing between them. In particular, the predetermined spacing is based on an optical transmission signal, for example. This spacing is optionally determined such that an evanescent field can be generated by the optical transmission signal (which is conducted particularly through the two structural elements), and this generates a time-dependent charge shift in the structural elements. For example, the predetermined spacing can be a gap between the metallic structural elements. This spacing allows for, for example, adaptation or adjustment of plasmonic resonance and, in particular, field elevation between the structures.

[0041] This spacing can be between the nanometer and micrometer ranges.

[0042] In particular, optical transmission signals can be coupled between two metal structures and especially between the gaps between the metal structures. Depending on the spacing between the metal structural elements, an evanescent field can be generated by the optical transmission signal, thereby inducing time-dependent charge shifts in the structural elements. This induced charge shift and the spacing between the structural elements can generate plasmon resonance and, in particular, field elevation. Charge separation between the structural elements is achieved upon reception, thereby enabling modulation of the refractive index of the optical transmission signal. In one embodiment, a coupling element, especially an optical coupling element, is arranged between the two metal structural elements, wherein the coupling element is configured to couple the optical transmission signal between the two metal structural elements. In particular, the coupling element is arranged within the spacing between the metal structural elements, so that the optical transmission signal or optical carrier signal can propagate between the two structural elements, especially through its evanescent field, particularly for plasmon resonance and field elevation. The coupling element can be, for example, a waveguide, such as a linear waveguide. For example, the coupling element can be an optical path between the metal structural elements.

[0043] In one embodiment, at least one antenna structure is further configured to generate an optical output signal based on the metallic structural elements and the electrically received signal. Therefore, the metallic structural elements and, in particular, the antenna structure, can be used as a receiving antenna for a receiving device. Specifically, the optical output signal can be modulated based on the electrically received signal by means of the metallic structural elements and the optical transmission signal coupled therein, through plasma resonance and field elevation. Thus, in the case of receiving electromagnetic radiation (such as an electrically received signal), the optical output signal is modulated by means of plasma resonance and field elevation between the structural elements. In particular, the antenna structure can be used as an antenna for a transmitting device and also as an antenna for a receiving device.

[0044] When the antenna structure is used as a receiving antenna, the optical transmission signal can be modulated in time within the coupling element by an external electromagnetic field through induced modulation of the plasma field elevation and refractive index.

[0045] In one embodiment, the transmitting device is further configured to have an optical modulation unit for modulating an optical transmission signal, wherein at least one antenna structure is configured to generate an electrical radar transmission signal based on a metallic structural element and the modulated optical transmission signal.

[0046] Therefore, in an alternative embodiment, the antenna structure can be used as a transmitting antenna for a transmitting device. With the aid of the antenna structure and the modulated optical transmission signal, frequency conversion can be performed by means of plasma resonance and field elevation, thus generating an electrical radar signal and transmitting it into the vehicle's surrounding environment. Therefore, the antenna structure can be used, for example, for radiated emission. For example, with the aid of an optical modulation unit, the optical carrier signal or optical transmission signal can be modulated in time before being coupled into the substrate or into the antenna structure. This modulation triggers a time-varying plasma resonance as light propagates in the waveguide or in the coupling element according to the spacing or gaps between the structural elements. This plasma resonance constructs a time-dependent electromagnetic field that can be emitted or emitted by the antenna structure.

[0047] In one embodiment, the radar sensor device is further configured to include a power amplifier unit for increasing the transmission power of at least one antenna structure. Additionally or alternatively, the radar sensor device may include a phase-locked loop unit for feeding back optical transmission signals in both structural elements.

[0048] For example, a power amplifier unit can be a power amplifier. A power amplifier unit can, for example, be used as an integrated electronic power amplifier for a transmitting device. Therefore, the power of the emitted radiation can be increased by means of a power amplifier unit. Thus, radar sensor devices can be used for better environmental detection in vehicles. For example, the power amplifier unit can be integrated on a semiconductor chip with the same structure as the antenna. For example, an additional measuring unit can be used to measure or evaluate the optical carrier signal or the transmitted signal, and in this regard, feedback can be provided to the power amplifier unit used for emitting radiation.

[0049] Phase-locked loop (PLL) units can also be integrated, for example, into a semiconductor chip on which the antenna structure is integrated. The PLL unit can be an optical unit. In particular, this PLL unit can be referred to as an "optical phase-locked loop." For example, the PLL unit can be used to detect optical transmission signals and provide feedback to antenna structure or metal structural elements. Thus, an adjustment loop can be provided. For example, the PLL unit can be controlled by means of an oscillator. Furthermore, this unit can be used to measure optical carrier signals and provide feedback to a power amplifier unit used for transmitted radiation.

[0050] In one embodiment, an additional metal structural element is arranged between the two metal structural elements, wherein the two metal structural elements and the additional metal structural element have the same material properties. In particular, the structural elements have the same dielectric material or properties. In particular, the additional structural element may be constructed of the same material as the two metal structural elements, or a semiconductor material or a metallic material.

[0051] In particular, the metallic structural elements can be referred to as intermediate structures. Furthermore, additional metallic structural elements can be coordinated to resonate with the radiation to be detected, especially the electrical received signal. For example, in the case of radar radiation from a 77 GHz radar sensor device, the intermediate structure could be 3.9 mm in length, particularly between 3.7 and 4.1 mm. This is specifically based on the ratio of the dielectric constants of the surrounding structures. By means of additional metallic structural elements, the resonance can be maximized while simultaneously maximizing plasma resonance, allowing waveguides or coupling elements to be used for maximum modulation of the optically transmitted signal.

[0052] For example, each metal structural element may have its own coupling element or waveguide integrated between it and another metal structural element, which in turn connects to an optical input port. For instance, two coupling elements located between the intermediate structure and the metal structural element may then have a phase offset from each other. Therefore, in this implementation, the antenna structure can have multiple interaction regions and exhibit a structure that resonates with radar radiation.

[0053] In one embodiment, the two metal structural elements are further configured to have triangular, quadrilateral, or polygonal shapes. In particular, the opposing sides of the two structural elements may be arranged parallel to each other. Specifically, the shape or geometry of the two metal structural elements can be adapted according to the application of the radar sensor device and, in particular, the antenna structure. For example, the two metal structural elements may have a triangular shape. For this purpose, the additional metal structural element may have a square shape, such that the corresponding tips of the metal structural elements are oriented towards the other metal structural element. In particular, the two metal structural elements and the additional metal structural element may have arbitrary geometries. This should be selected according to the application of the radar sensor device and, in particular, the required plasma resonance.

[0054] Another aspect of the invention relates to a radar system having at least one radar sensor device according to a prior aspect and a central electronic computing device, wherein,

[0055] -The central electronic computing equipment is configured to generate optical transmission signals and receive optical output signals for radar sensor devices.

[0056] -The central electronic computing device is coupled to the optical input and optical output ports of the radar sensor device via at least one glass fiber.

[0057] - The central electronic computing device includes a laser device configured to generate an optical transmission signal and couple it into at least one glass fiber coupled to the optical input port of a radar sensor device, and

[0058] - The central electronic computing device has an optical receiving unit configured to receive optical output signals via at least one glass fiber coupled to the optical output port of a radar sensor device and determine the radar information derived therefrom.

[0059] For example, the received signal from the antenna structure can be transmitted to a central electronic computing device and converted for data processing by means of conventional electro-optic frequency conversion or by means of an additional plasma antenna. For example, the central electronic computing device can be coupled to multiple radar sensor devices. In particular, the central electronic computing device can be connected to multiple transmitting and receiving modules. Here, the transmitting and receiving modules can be connected via optical phase or electronic interfaces, or for example, via Ethernet. The central electronic computing device or central unit provides all necessary control and data processing signals and provides the corresponding modules and interfaces for this purpose.

[0060] The central electronic computing device can be configured to generate optical transmission signals and receive optical output signals for the radar sensor device, and the central electronic computing device is coupled to the optical input port and optical output port of the radar sensor device via at least one glass fiber.

[0061] Such radar systems can be used, in particular, in motor vehicles, in automated systems, in aviation technology, or in aerospace technology. Further possibilities for implementations of the radar system and / or radar sensor device according to the invention include polarization-sensitive detection through the shaping of the antenna geometry.

[0062] Similarly, it can be applied to data transmission in the 5G band or higher frequency bands. Likewise, by using an optical ring resonator as a receiving antenna, data transmission can be used for Vehicle-2-X applications, such as software updates, map updates, and infrastructure signals. Similarly, the radar sensor device can also be used as a passive detector element for environmental perception. It is also conceivable that this radar sensor device can be used to detect emitted radiation used for communications, such as radio, long-range communications, satellite communications, or similar camera systems.

[0063] In particular, the radar system just proposed can have the radar sensor devices described in the preceding aspect. Specifically, the radar system can have multiple radar sensor devices.

[0064] A radar sensor device can be a co-integrated transmitting unit and / or receiving device that uses a specific structure or component of an optical ring resonator as an antenna.

[0065] This radar system is particularly advantageous for use in motor vehicles, as it requires a sensor system distributed around the vehicle to enable efficient environmental perception. Therefore, multiple radar sensor units can be distributed throughout the vehicle, and these multiple radar sensor units can be networked and communicated via a central electronic computing device. Thus, the radar system requires one, especially a single, central electronic computing device, particularly a central station. With the aid of the central electronic computing device, various different radar sensor units can be supplied with optical transmission signals, while the central electronic computing device can receive optical output signals or other signals at the corresponding optical output ports of the radar sensor units.

[0066] In particular, the central electronic computing device is a physically separate unit from the radar sensor device. Specifically, the central electronic computing device is not a component of the radar sensor device. The central electronic computing device can be a different semiconductor chip or integrated circuit compared to the radar sensor device.

[0067] For example, FMCW signals can be executed with the help of a central electronic computing device.

[0068] The system tracks, processes, and evaluates a frequency-modulated continuous wave signal. Furthermore, it can perform both transmitting and receiving operations using radar sensor devices.

[0069] In particular, the central electronic computing equipment can generate optical carrier frequencies, especially optical transmission signals, within the terahertz frequency range. The signal to be transmitted, especially the optical transmission signal, at one-eighth of the radar frequency of the radar system, is modulated onto this optical carrier frequency and transmitted or transmitted to the radar sensor device with optical phase or amplitude modulation or frequency modulation. In this way, the frequency can be multiplied eightfold, thereby enabling radar radiation, especially radar-embedded signals. Signal detection is performed in the reverse manner. All data is processed at the central station, especially on the central electronic computing equipment.

[0070] The central electronic computing device is coupled to the optical input and output ports of the radar sensor device via one or more glass fibers. Therefore, the optical transmission signal generated by the central electronic computing device is coupled into the glass fibers and transmitted to the optical input port of the radar sensor device via optical signal transmission. Thus, the transmission of the carrier signal or radar drive signal occurs via the optical transmission path. In particular, the glass fiber can be a glass fiber line. Similarly, the central electronic computing device is coupled to the optical output port via the glass fibers. Therefore, the radar sensor device, especially the modulation device of the radar sensor device, can couple the optical output signal into the glass fibers and transmit it to the central electronic computing device to evaluate the received radar radiation.

[0071] For example, the central electronic computing device is configured to have a laser device that generates an optical transmission signal and couples it into at least one glass fiber coupled to the optical input port of a radar sensor device. Similarly, the central electronic computing device is equipped with an optical receiving unit configured to receive an optical output signal via at least one glass fiber coupled to the optical output port of the radar sensor device.

[0072] In particular, optical transmission signals can be generated or produced based on a carrier signal, especially based on a carrier frequency, using a laser device or light source (which can be a CW laser in particular). For this purpose, electrical control signals can be considered in particular. The optical receiving unit may additionally have an evaluation unit, wherein the optical output signal received by the optical receiving unit can be evaluated using the evaluation unit.

[0073] For example, a central electronic computing device may have fiber output ports and fiber input ports.

[0074] Another aspect of the invention relates to a vehicle having a radar system according to the preceding aspect or an improvement thereof. In particular, the vehicle or motor vehicle just described includes a radar system according to the preceding aspect.

[0075] Therefore, radar systems can be used for environmental detection around motor vehicles and / or for observing the interior space of vehicles, such as for intrusion detection, seat occupancy detection, etc.

[0076] For example, the vehicle could be a passenger car, a freight car, a bus, a tram, a subway / light rail, a train, or an unmanned transportation system in a production area. For example, the vehicle could be highly automated. For example, multiple radar sensor units could be distributed over a large area in an array configuration within or at the vehicle. For example, a sparse array configuration could be used for this purpose.

[0077] For example, multiple individual chip modules or radar sensor devices can be arranged in a vehicle and connected to a central electronic computing device. This can be used, for example, in a vehicle's ADAS (Advanced Driver Assistance System). For instance, radar sensor devices, particularly receiving and / or transmitting modules, can be located in the windshield, rear window, side windows, roof, or bumper. Furthermore, it is conceivable that sensor devices are positioned downwards, beneath the vehicle, pointing towards the road. These sensor devices can be used for lane condition recognition, motion estimation, and / or localization.

[0078] An embodiment of a single aspect of the invention should be considered as an advantageous embodiment of the other aspects. In particular, a corresponding embodiment of a single aspect can be considered as an advantageous embodiment of all other aspects. This also applies in reverse.

[0079] Advantageous design practices for radar sensor devices should be considered advantageous design practices for radar systems and vehicles.

[0080] The present invention also includes improvements to the radar system according to the invention, the vehicle according to the invention, and the method according to the invention, said improvements having the features already described in relation to improvements to the radar sensor device according to the invention. For this reason, corresponding improvements to the radar system according to the invention and the vehicle according to the invention will not be described here.

[0081] The present invention also includes combinations of features of the described embodiments. Attached Figure Description

[0082] Embodiments of the present invention are described below. Wherein:

[0083] Figure 1A schematic diagram of a vehicle containing a radar system is shown;

[0084] Figure 2 It shows Figure 1 A schematic diagram of the radar sensor devices and computing equipment in the radar system;

[0085] Figure 3 It shows Figure 2 A schematic diagram of the antenna structure of the radar sensor device in the image;

[0086] Figure 4 It shows Figure 3 The diagram shows the antenna structure, which serves as the receiving antenna in this example.

[0087] Figure 5 It shows Figure 3 The diagram shows the antenna structure, which serves as the transmitting antenna in this example.

[0088] Figure 6 It shows Figure 3 A schematic diagram of another embodiment of the antenna structure;

[0089] Figure 7 It shows Figure 3 A schematic diagram of another embodiment of the antenna structure;

[0090] Figure 8 It shows Figure 3 A schematic diagram of another embodiment of the antenna structure;

[0091] Figure 9 It shows Figure 3 A schematic diagram of another embodiment of the antenna structure; and

[0092] Figure 10 It shows Figure 2 A schematic diagram of another embodiment of the radar sensor device. Detailed Implementation

[0093] The embodiments described below are preferred embodiments of the invention. In these embodiments, the described components each constitute a single feature of the invention that should be considered independently of each other, and these features also independently further extend the invention, and therefore can be considered individually or in combinations other than those shown as part of the invention. Furthermore, the described embodiments can also be supplemented by additional features among the already described features of the invention.

[0094] In the figure, components with the same function are given the same reference numerals.

[0095] Figure 1A schematic diagram of vehicle 1 is shown, which may be a motor vehicle. Vehicle 1 includes, for example, a radar system 2.

[0096] Radar system 2 can be, for example, a sensor system or an environmental sensor system of vehicle 1. For this purpose, radar system 2 can, for example, communicate and network with one or more driver assistance systems or other vehicle systems. For example, radar system 2 can be a radar sensor, a lidar sensor, or other types of sensors, especially sensors for vehicles. In addition to its use in vehicle 1, radar system 2 can also be used in systems external to the vehicle.

[0097] Figure 2 An example view of radar system 2 is shown. Radar system 2 may have at least one radar sensor device 3 and a central electronic computing device 4. For example, radar sensor device 3 and central electronic computing device 4 may be separate and physically separated units. Central electronic computing device 4 is a central unit. For example, central electronic computing device 4 may generate electrical control signals, which can be used to manipulate or control laser device 5. Laser device 5 may be, for example, a CW laser. Optical transmission signals or carrier signals 6 may be generated by means of laser device 5. Optical transmission signals 6 may in particular be referred to as optical carrier signals in the terahertz frequency range. Central electronic computing device 4 may, for example, generate an optical carrier frequency. The signal to be transmitted, carrying one-eighth of the radar frequency, is modulated onto this optical carrier frequency and transmitted, for example, to radar sensor device 3. In this way, the frequency can be multiplied by eight. Radar sensor device 3 may also receive signals in the gigahertz frequency range and transmit them to central electronic computing device 4.

[0098] For example, the central electronic computing device 4 can be coupled to the optical input port 9 and optical output port 9 of the radar sensor device 3 via at least one glass fiber 7. Therefore, bidirectional signal transmission can be performed between the central electronic computing device 4 and the radar sensor device 3.

[0099] Furthermore, the central electronic computing device 4 may have an optical receiving unit 10 configured to receive an optical output signal 11 provided via the optical output port 9 of the radar sensor device 3. Therefore, the central electronic computing device 4 can be coupled to the radar sensor device 3 via optical fiber or an electronic interface (e.g., the Internet). In particular, multiple radar sensor devices can be coupled to the central electronic computing device 4. For example, the central electronic computing device 4 may have a processing unit 12 or a computing unit capable of processing the received optical output signal. Therefore, signal detection and subsequent data processing of the received output signal 11 can be performed.

[0100] In particular, the central electronic computing device 4 may have or provide all necessary control signals, data processing signals, modules and interfaces.

[0101] For example, in addition to the optical input port 8 and the optical output port 9, the radar sensor device 3 may also have a transmitting device 13 and a receiving device 14. Therefore, the radar sensor device 3 has a receiving module and / or a transmitting module. In particular, the transmitting device 13 and the receiving device 14 can be integrated onto the same chip. Alternatively, it is conceivable that the transmitting device and the receiving device reside on different semiconductor chips.

[0102] With the aid of the transmitting device 13, the electrical radar signal 15 based on the optical transmission signal 6 can be transmitted into the surrounding environment 17 of the vehicle 1. Therefore, a corresponding radar signal 15 can be transmitted according to the optical transmission signal 6. If this signal 15 is now reflected by an object (such as a traffic participant, road, tree, or other object) in the surrounding environment 18, an electrical receiving signal 16 corresponding to the electrical radar signal 15 and reflected in the surrounding environment 17 can be received.

[0103] For example, the transmitted radar signal 15 and the received signal 16 can be in the terahertz or gigahertz frequency range. Therefore, by means of the radar system 2, frequency conversion of the terahertz carrier signal, especially the transmission signal 6, to the gigahertz frequency range can be performed for transmission. Conversely, reception of the gigahertz signal and modulation onto the terahertz carrier signal can be performed.

[0104] exist Figure 3 A schematic view of antenna structure 18 is shown. This antenna structure 18 can function as a transmitting antenna not only for transmitting device 13 but also for receiving device 14. Therefore, antenna structure 18 is used not only for transmitting device 13 but also for receiving device 14. In particular, antenna structure 18 is a plasma antenna structure, especially a plasma detector unit. Antenna structure 18 has two opposing and spaced-apart metallic structural elements 19, 20. These metallic structural elements 19, 20 can be metallic nanostructures or microstructures.

[0105] Antenna structure 18 may be integrated or arranged on semiconductor chip 21, for example.

[0106] Similarly, it is conceivable that the antenna structure 18 is integrated on a photonic chip or an electro-photonic chip. It is also conceivable that it is integrated on an optical carrier substrate or a polymer substrate.

[0107] In particular, the antenna structure 18 is configured to generate an electrical radar transmitted signal 15 and modulate a received electrical received signal 16 based on the metal structural elements 19 and 20.

[0108] In particular, at least two of the two metal structural elements 19, 20 are arranged relative to each other with a predetermined spacing 22 or gap. Specifically, the two structural elements 19, 20 do not contact each other. A coupling element 23 may be arranged within this spacing 22. The coupling element 23 may be configured as an optical waveguide and coupled or connected to the optical input port 8. Therefore, the optical transmission signal 6 can be coupled into the coupling element 23 and conducted or coupled between the two structural elements 19, 20. For example, the two metal structural elements 19, 20 may have triangular, quadrilateral, or polygonal shapes. In this case, these metal structural elements have corresponding triangular shapes, wherein the two apexes of the corresponding triangular shapes are oriented relatively abutting each other. Therefore, the coupling element 23 is arranged between the two apexes of the triangular shapes of the structural elements 19, 20.

[0109] In one embodiment of antenna structure 18, the transmission signal 6 can be coupled into semiconductor chip 21 via an optical input port 8, for example, configured as a photonic interface or a lattice coupler. For this purpose, semiconductor chip 21 also has a coupling element 23. The optical transmission signal, particularly light 6, can propagate due to the extension of coupling element 23 through its spacing 22. If the spacing between structural elements 19, 20 is as small as possible and has a predetermined minimum spacing, charge displacement in structural elements 19, 20 can be achieved by the evanescent field of the transmission signal 6. For this purpose, the resonance condition is also followed. In particular, this can be achieved considering fundamental resonance or higher harmonic resonance. Due to spacing 22, plasma resonance can be generated through this induced charge displacement. This can be used to transmit time-modulated optical signals to antenna structure 18, corresponding to frequency compression.

[0110] exist Figure 4 An embodiment of antenna structure 18 is shown, in which the antenna structure can be used to receive electromagnetic radiation, particularly electromagnetic radiation in the surrounding environment 17 of vehicle 1. Reference can be made to the already described content regarding plasma resonance and, in particular, field elevation. If the electrically received signal 16 now comes into contact with antenna structure 18, this induces a time-varying charge separation between structures 19, 20. This results in modulation of the refractive index within coupling element 23, causing the optical transmission signal 6 to be modulated in time and to incorporate characteristics of the external field, particularly radar information. Charge separation is achieved between structural elements 19, 20 through plasma resonance or plasma resonance 24. As illustrated exemplarily in this embodiment, positively charged ions or charge carriers are located at the tips of structural elements 19 and negatively charged ions or charge carriers are located at the tips of structural elements 20. Therefore, antenna structure 18 can generate or modulate optical output signal 11 based on the electrically received signal 16 according to the metallic structural elements 19, 20 and, in particular, plasma resonance 24.

[0111] In particular, the arrangement of structural elements 19 and 20 can generate field elevation in addition to plasma resonance 24. This is especially advantageous for frequency conversion. Therefore, the information contained in the electrical received signal 16 is converted into the output signal 11 as information through temporal modulation. Thus, the output signal 11 contains radar information, and in particular environmental information of the surrounding environment 17.

[0112] exist Figure 5 An embodiment is now shown in which the antenna structure 18 of the radar sensor device 3 operates as a transmitting antenna. For this purpose, the radar sensor device 3 may have an optical modulation unit 25. By means of this optical modulation unit 25 (which may be referred to, for example, as an optical modulator), the optical transmission signal 6 can be modulated in time, thereby providing a time-modulated transmission signal 26 to the optical input port 8 for coupling in this embodiment. Thus, the optical signal 6 is modulated in time before coupling. The modulated signal 26 can trigger a time-varying plasma resonance 24, which constructs a time-dependent electromagnetic field. This electromagnetic field can then be emitted by the antenna structure 18 into the surrounding environment 17. In particular, the modulated signal 26 coupled to the coupling element 23 can trigger a plasma resonance between the spacing 22. This plasma resonance, for example, moves positive and negative charge carriers, thereby generating an electrical radar transmission signal 15. For example, structural elements 19, 20 can be constructed as gold structural tips. Similarly, structural elements 19, 20 can be implemented using dielectric materials.

[0113] exist Figure 6 Another embodiment of antenna structure 18 is shown, for example, when used as a transmitting antenna.

[0114] For this purpose, for example, an electronic power amplifier or power amplifier unit 27 can be integrated onto a semiconductor chip 21. This semiconductor chip increases the power of the emitted radiation, thereby allowing the radar signal 15 to be used more efficiently for environmental detection. In particular, this increases the effective range of the radar sensor assembly 3. Similarly, the increased power improves the probability of detection.

[0115] For example in Figure 7 Another embodiment of the antenna structure 18 in transmission operation is shown. Here, the antenna structure 18 may additionally or alternatively have a phase-locked loop unit 28 or a phase-locked loop in addition to the power amplifier unit 27. Therefore, the antenna structure 18 has a control unit or control system, thereby enabling feedback or refeedback of the optical carrier signal or transmitted signal 6. This can also be used to increase the transmission power and thus result in an improved radar sensor device or radar system 2.

[0116] exist Figure 8Another design scheme for the antenna structure 18 of the radar sensor device 3 is shown. Here, in order to simultaneously enhance, and especially maximize, the plasma resonance 24, additional, supplementary metal structural element 29 may be provided. This metal structural element is constructed similarly to structural elements 19 and 20. However, it may have a different geometry relative to the other two structural elements 19 and 20. In this case, structural elements 19 and 20 are shaped as triangles while the additional structural element 29 is shaped as a rectangle. This additional structural element 29, or intermediate structure, may be arranged between the tips of structural elements 19 and 20. The predetermined spacing 22 may exist between structural elements 19 and 29 and between structural elements 20 and 29, respectively. For example, the additional structural element 29 may be coordinated with the radar radiation of the radar system 2. For example, in the case of radar radiation between 70 GHz and 85 GHz, especially 77 GHz, the additional structural element 29 may have a length of, for example, 3.9 mm. Because there are now two gaps or spacings between the corresponding structural elements 19, 20 and the additional structural element 29, additional optical input ports 30 and additional coupling elements 31 are used, for example. These additional optical input ports and additional coupling elements are constructed similarly to the previously described units 8, 23. The additional input port 30 is also coupled to the central electronic computing unit 4 via at least one glass fiber 7. Therefore, the antenna structure 18 here has at least two interaction regions in which plasma resonance can be generated. Due to the two coupling elements 23, 31, a phase shift can exist between the corresponding signals.

[0117] pass Figure 8 The exemplary arrangement shown in the diagram can maximize or enhance the modulation of the electrical received signal 16 and / or the transmitted signal 6. Therefore, the radar sensor device 3 and thus the radar system 2 can be used more efficiently in the vehicle.

[0118] For example, the longitudinal structure can serve as an additional structural element 29 to increase or expand the interaction region of the antenna structure 18. This coordinated longitudinal structure is particularly coordinated with the radiation to be detected in terms of resonance.

[0119] exist Figure 9 An exemplary illustration of antenna structure 18 is shown. This antenna structure can be used not only for transmitting but also for receiving. In this embodiment, structural elements 19 and 20 have an elongated, particularly slatted, shape. In particular, structural elements 19 and 20 have a longitudinal structure. This longitudinal structure can be coordinated with the resonance of the radiation to be detected, particularly the received signal 16. Thus, the interaction region in which plasma resonance 24 can be generated can be increased or realized. In particular, in this case, the two structural elements 19 and 20 can be arranged parallel to each other on the semiconductor chip 21.

[0120] Figure 10 A possible design for the radar sensor device 3 is shown. For example, multiple antenna structures 18 can be connected into a single array. This can be implemented together on a semiconductor chip 21, thus forming a plasma antenna array. This is particularly advantageous for efficient environmental detection of vehicles.

[0121] List of reference numerals

[0122] 1 vehicle

[0123] 2. Radar System

[0124] 3. Radar sensor device

[0125] 4. Central electronic computing equipment

[0126] 5. Laser equipment

[0127] 6. Optical transmission signal

[0128] 7. Fiberglass

[0129] 8 Optical input ports

[0130] 9 Optical output ports

[0131] 10 Receiving Unit

[0132] 11 Optical Output Signal

[0133] 12 processing units

[0134] 13 Transmitting equipment

[0135] 14 Receiving equipment

[0136] 15. Radar emits a signal.

[0137] 16 Electrical signal reception

[0138] 17. Surrounding Environment

[0139] 18 Antenna Structure

[0140] 19,20 Metal structural components

[0141] 21 Semiconductor Chips

[0142] 22 spacing

[0143] 23 Coupling element

[0144] 24 Plasma Resonance

[0145] 25 Optical modulation units

[0146] 26 Modulated optical transmission signal

[0147] 27 Power Amplifier Unit

[0148] 28 Phase-locked Loop Units

[0149] 29 Other structural elements

[0150] 30 Additional optical input ports

[0151] 31 Other coupling elements

[0152] l Length of other structural components

Claims

1. A radar sensor device (3) for a vehicle (1), comprising: - Optical input port (8), which is used to receive optical transmission signals (6); - Transmitting device (13), the transmitting device being used to transmit an electrical radar emission signal (15) based on the optical transmission signal (6) to the surrounding environment (17) of the vehicle (1); - A receiving device (14) for receiving an electrical received signal (16) corresponding to the signal (15) emitted by the electrical radar and reflected in the surrounding environment (17); and Its features - At least one antenna structure (18) having two opposing and spaced-apart metallic structural elements (19, 20), wherein - The at least one antenna structure (18) is configured to generate an electrical radar emitted signal (15) and modulate a received electrical received signal (16) according to the metal structural elements (19, 20).

2. The radar sensor device (3) according to claim 1, Its features are, The two metal structural elements (19, 20) have a predetermined distance (22) between them.

3. The radar sensor device (3) according to claim 1 or 2, Its features are, A coupling element (23) is arranged between the two metal structural elements (19, 20), wherein the coupling element (23) is configured to couple the optical transmission signal (6) between the two metal structural elements (19, 20).

4. The radar sensor device (3) according to claim 1 or 2, Its features are, The at least one antenna structure (18) is configured to generate an optical output signal (11) based on the metal structural elements (19, 20) and the electrical received signal (16).

5. The radar sensor device (3) according to claim 1 or 2, Its features are, The transmitting device (13) has an optical modulation unit (25) for modulating the optical transmission signal (6), wherein the at least one antenna structure is configured to generate the electrical radar emission signal (11) based on the metal structural elements (19, 20) and the modulated optical transmission signal (26).

6. The radar sensor device (3) according to claim 1 or 2, Its features - A power amplifier unit (27), said power amplifier unit being used to increase the transmission power of the at least one antenna structure (18), and / or - A phase-locked loop unit (28) for feeding back the optical transmission signal (6) in the two structural elements (19, 20).

7. The radar sensor device (3) according to claim 1 or 2, Its features are, Another metal structural element (29) is arranged between the two metal structural elements (19, 20), wherein the two metal structural elements (19, 20) and the other metal structural element (29) have the same material properties.

8. The radar sensor device (3) according to claim 1 or 2, Its features are, The two metal structural elements (19, 20) have triangular, quadrilateral or polygonal shapes.

9. The radar sensor device (3) according to claim 8, Its features are, The opposing sides of the two structural elements (19, 20) are arranged parallel to each other.

10. A radar system (2) comprising at least one radar sensor device (3) according to any one of claims 1 to 9 and a central electronic computing device (4), wherein, - The central electronic computing device (4) is configured to generate optical transmission signals (6) and receive optical output signals (11) of the radar sensor device (3). - The central electronic computing device (4) is coupled to the optical input port (8) and optical output port (9) of the radar sensor device (3) via at least one glass fiber (7), respectively. - The central electronic computing device (4) has a laser device (5) configured to generate the optical transmission signal (6) and couple it into at least one glass fiber (7) coupled to the optical input port (8) of the radar sensor device (3), and - The central electronic computing device (4) has an optical receiving unit (10) configured to receive the optical output signal (11) via at least one glass fiber (7) coupled to the optical output port (9) of the radar sensor device (3) and determine the radar information derived therefrom.

11. A vehicle having a radar system (2) according to claim 10.

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