Multiband sensor system for detecting surroundings, method, and motor vehicle

Abstract

The invention relates to a sensor system (2) for detecting surroundings, comprising — an optical device (6) for generating an optical carrier signal (7) and — a transmission device (4) which is designed to emit electric emission signals (16, 17, 18) which are based on the optical carrier signal (7), having: — an electro-optical modulator (8) which has a specified working point (10), wherein — the electro-optical modulator (8) is designed to generate a plurality of optical emission signals (9) on the basis of the specified working point (10) and the optical carrier signal (7) such that the plurality of optical emission signals (9) have frequency bands (20, 21, 22) which differ from one another, and — the transmission device (4) is designed to convert the plurality of optical emission signals (9) into a plurality of electric emission signals (16, 17, 18) and emit the plurality of electric emission signals (16, 17, 18) by means of at least one radio-based transmission unit (12, 13, 14). The invention additionally relates to a method and a motor vehicle (2).

Description

[0001] Description

[0002] Multi-band sensor system for environment detection, as well as process and motor vehicle

[0003] The invention relates to a sensor system for environmental detection. The sensor system comprises an optical device for generating an optical carrier signal. The sensor system also comprises a transmitting device configured to transmit electrical signals based on the optical carrier signal.

[0004] Furthermore, the invention relates to a method for operating a sensor system.

[0005] The invention also relates to a motor vehicle with a sensor system.

[0006] US 2021 / 0 055 387 A1 discloses a coherent LIDAR system. This comprises a light source configured to emit locally oscillated light and light pulses, each coherent with a corresponding portion of the locally oscillated light. Furthermore, the LIDAR system includes a laser and an amplifier. Furthermore, the LIDAR system includes a receiver configured to receive the locally oscillated light and the light pulses in order to determine a distance to an object.

[0007] For example, US 2021 / 0 072 381 A1 further discloses a system and method for improved velocity resolution and signal-to-noise ratio in optical phase-encoded ranging. An electrical signal generated by mixing a first optical signal and a second optical signal can be received, the first optical signal being generated by modulating an optical signal, and the second optical signal being generated in response to transmitting the first optical signal to a value. A Doppler frequency shift of the second optical signal can be determined, and a corrected electrical signal can be generated by adjusting the electrical signal based on the Doppler frequency shift. A distance to an object can be determined based on a cross-correlation of the correlated electrical signal with a radio-frequency signal.Furthermore, US 11,032,009 B1 discloses a method for transmitting a signal from a user device in a wireless communication system. Furthermore, the method comprises generating an optical signal related to data transmission, combining an electrical signal for the data with the optical signal, and transmitting a combined signal.

[0008] An object of the present invention is to provide a sensor system which can be used more extensively while minimizing its complexity.

[0009] This problem is solved by a sensor system, a method, and a motor vehicle according to the independent patent claims. Useful further developments arise from the dependent patent claims.

[0010] One aspect of the invention relates to a sensor system for environmental detection, comprising an optical device for generating an optical carrier signal, a transmitting device which is designed to transmit electrical transmission signals based on the optical carrier signal, comprising: an electro-optical modulator which has a predetermined operating point, the electro-optical modulator which is designed to generate a plurality of optical transmission signals based on the predetermined operating point and the optical carrier signal such that the plurality of optical transmission signals have different frequency bands from one another, and the transmitting device which is designed to convert the plurality of optical transmission signals into a plurality of electrical transmission signals and to transmit the plurality of electrical transmission signals with at least one radio-based transmission unit

[0011] The proposed sensor system can be used to create a radar system or a LIDAR-radar combination system that has a lower complexity and yet uses several frequency bands by means of one, in particular a single, electro-optical modulator.

[0012] Unlike current optically assisted radar systems, the proposed sensor system uses multiple frequency bands, or radar frequency bands, for object detection. The electro-optical modulator of the sensor system according to the invention eliminates the need for a separate phase shifter to generate the bands, unlike known multi-band optically assisted radar systems. Previously, such radar or frequency bands were subsequently separated using an optical filter, and the radar ramp was modulated in a separate electro-optical modulator. This can be improved by the proposed sensor system.

[0013] In particular, the proposed sensor system requires only one electro-optical modulator for generating radar signals and / or LIDAR signals in different frequency bands. For example, the sensor system can be a radar system or a LIDAR radar system. For example, the sensor system can be used as a photonic multi-band LIDAR radar system.

[0014] Unlike prior art sensor systems, the proposed sensor system does not use separate hardware components for each individual frequency band generation. Using the electro-optical modulator, the proposed sensor system allows different frequency bands to be generated with the same component or unit.

[0015] Furthermore, the proposed sensor system enables multiple bands or frequency bands to be controlled with dedicated hardware, in particular a single piece of hardware, such as the electro-optical modulator. This minimizes the costs and complexity of the overall system, particularly the sensor system for environmental detection. A further advantage of the sensor system according to the invention is, for example, that the sensor system can dispense with a mode-locked laser (MLL) and separately controlled phase shifters for generating different frequency bands. Likewise, optical bandpass filters, which separate the bands from each other before each individual frequency band is controlled separately, can be dispensed with. This can be dispensed with by the proposed sensor system.

[0016] Since several frequency bands or radar bands can be generated or controlled by means of a unit or a hardware component using the electro-optical modulator of the sensor system, the complexity, the probability of failure and the costs of the sensor system according to the invention can be reduced compared to sensor systems in the prior art.

[0017] By omitting a phase shifter, which is not possible in the prior art, costs and complexity can be reduced. By omitting a mode-locked laser (MLL), which is used in known systems to generate the frequency bands, further advantages of the sensor system according to the invention arise. Due to their design, MLLs have a short lifetime and are very expensive. This increases the probability of failure of the system containing the MLL and the system cannot be implemented cost-effectively. Separating the frequency bands requires additional optical bandpass filters, which are very expensive discretely and generate additional energy, such as additional heat dissipation, which in turn must be compensated. This increases the power loss of the system and therefore the system's cost.These disadvantages of using an MLL can be solved with the proposed sensor system.

[0018] In contrast to the state of the art, the proposed sensor system requires only one electro-optical modulator to generate multiple frequency bands or radar bands. Furthermore, thanks to the optical clock distribution, the sensor system can also be used for systems for large-scale equipment.

[0019] With slight modifications to the hardware, the sensor system can be used as a radar system or as a combined radar-LIDAR system. By selecting the required sensor system components, the sensor system can be implemented as a discrete, integrated, or semi-integrated solution.

[0020] In contrast to the lifetime problems of a mode-locked laser, the electro-optical modulator has a longer lifetime, which in turn has a positive effect on the sensor system.

[0021] In particular, the electro-optical modulator is designed such that it can generate multiple optical signals having different frequency bands. For this purpose, the electro-optical modulator can be operated at a predetermined or specific operating point. For example, the electro-optical modulator can be driven or operated as an operating point at a point in which many, or at least some, harmonics of possibly identical amplitudes can be generated. In particular, the electro-optical modulator can be operated at an operating point in which at least two harmonic signals can be generated. A harmonic can be understood as a harmonic oscillation whose frequency is an integer multiple of a fundamental frequency. In this case, the fundamental frequency can be predetermined by the optical carrier signal. In particular, the Nyquist can be used as the operating point.Accordingly, the electro-optical modulator can have an operating mode that can be, or is, determined based on the Nyquist point. A Nyquist point, or critical point, is a point, taking into account the Nyquist criterion, up to which a system is stable. Furthermore, taking into account the Nyquist-Shannon sampling theorem, all components in a signal can have frequencies lower than the Nyquist frequency, so that the sampled signal can be reconstructed with any desired degree of accuracy. This is advantageous for the present sensor system because the corresponding radar or sensor information can be evaluated or reconstructed accordingly for object detection, particularly for environmental sensing.

[0022] Using the electro-optical modulator, three frequency bands, or the corresponding signals, can be used simultaneously for environmental detection, for example. This is particularly advantageous for improved location classification.

[0023] The multiple optical transmission signals can be generated coherently with each other, resulting in identical phases. Thus, the generated multiple transmission signals are coupled in phase synchronization with each other.

[0024] The proposed sensor system can be used in a wide variety of applications, such as aerospace, shipping, agriculture, automotive industry or automotive systems.

[0025] In particular, the sensor system can be used in at least partially autonomously moving motor vehicles, but especially also in fully autonomously operated motor vehicles. To enable such automated driving, reliable environmental perception is essential. The surroundings are recorded using sensors such as radar and / or LIDAR. A holistic 360-degree three-dimensional recording of the environment is particularly important, so that all static and dynamic objects can be detected. The sensor system can be used for this purpose. For example, the sensor system can be designed as a photonic radar system or photonic LI DAR radar system, with the electronic and photonic components co-integrated into one, especially a single, semiconductor chip.The tracking of an FMCW signal, as well as the entire signal processing and evaluation, can be performed in a central station or central computing device. For example, the optical device can be used to transmit a gigahertz signal as an optical carrier signal, particularly in the terahertz frequency range. A central station, which can also be referred to as a central electronic computing device, generates an optical carrier frequency, particularly the optical carrier signal. In particular, all data, especially for environmental detection, can be processed at the central station.

[0026] In particular, spectral properties of the optical transmission signals can be the same as those of the electrical transmission signals.

[0027] For example, the optical device or an optical laser can generate a 77 gigahertz FMCW signal as a carrier signal.

[0028] For example, at least the optical device can be provided to modulate the optical transmission signal or the optical carrier signal directly and / or by means of external components.

[0029] Specifically, the electro-optical modulator can be referred to as an electro-optical converter unit or electro-optical converter device.

[0030] In one embodiment, the electro-optical modulator is configured to additionally consider a high-frequency signal provided to the electro-optical modulator for generating the plurality of optical transmission signals. The electro-optical modulator can be configured and, in particular, operated in such a way that a plurality of optical transmission signals having different frequency bands can be generated. For this purpose, the electro-optical modulator is operated at the predetermined operating point, and the electro-optical modulator can be modulated, in particular additionally, with the high-frequency signal.

[0031] The high-frequency signal can, for example, be an RF signal (radio frequency signal). This high-frequency signal can cover a frequency range from nine kilohertz to the terahertz frequency range.

[0032] In one embodiment, the transmitting device comprises at least one optical-electronic converter unit, with which the plurality of optical transmission signals can be converted into the plurality of electrical transmission signals. For example, the plurality of optical transmission signals can be transmitted to the transmitting device via optical transmission paths or optical transmission links. This can be done, for example, via fiber optic connections. The transmitted plurality of optical transmission signals can then be converted by means of one or more optical-electronic converter units or optical-electrical converter devices, so that the plurality of electrical transmission signals can be provided or made available for transmission to the at least one radio-based transmitting unit, such as a radar sensor.

[0033] Additionally or instead, the transmitting device has at least one frequency manipulator with which at least one frequency band of one of the plurality of electrical transmission signals can be changed. For example, the transmitting device can have multiple frequency manipulators or mixers. With the aid of the at least one frequency manipulator, a frequency band of one of the plurality of transmission signals or multiple frequency bands of the plurality of electrical transmission signals can be converted into a higher or lower frequency band based on a defined bandwidth. Thus, frequency conversion can be carried out with the aid of the frequency manipulator. In other words, with the aid of the frequency manipulator, at least one frequency band of one of the plurality of electrical transmission signals can be manipulated for transmission, in particular for environmental detection.

[0034] Additionally or instead, the transmitting device comprises at least one electrical amplifier for amplifying at least one frequency band of one of the plurality of electrical transmission signals. In addition to the at least one electrical amplifier, the transmitting device may comprise further electrical amplifiers. In particular, an amplifier may be provided for each of the plurality of electrical transmission signals, so that a respective frequency band of a respective electrical transmission signal can be electrically amplified for transmission.

[0035] In one embodiment, the sensor system comprises an optical transmission unit of the transmission device. The optical transmission unit is designed to directly transmit at least one of the plurality of optical transmission signals. In other words, the transmission device can have various transmission options. Thus, the transmission device and thus the sensor system can comprise both at least one optical transmission unit and at least one radio-based transmission unit. Accordingly, the sensor system according to the invention can be designed as a radar-LIDAR combination system. Thus, the sensor system has expanded functionality, allowing it to be used more extensively. The sensor system thus has two measuring principles. This has an advantageous effect on environmental detection and, in particular, on the detection of objects in an environment. This has particular advantages for use in autonomously operated vehicles.

[0036] The transmitting device can, for example, be described as a combination device which can detect an object and / or its surroundings using radio-based, electrical, electromagnetic or optical signals.

[0037] The radio-based transmitting unit can be a device that can detect the surroundings using radio-based, electrical, and / or electromagnetic signals. Thus, for example, the radio-based transmitting unit can be a radar unit. The optical transmitting unit or an optically based transmitting unit can be a unit and / or a device that detects an object and / or the surroundings using optical signals, for example, the light from a laser and / or light-emitting diodes (LEDs). For example, the optical transmitting unit can be a LIDAR unit.

[0038] The generated multiple optical transmission signals can be provided or transmitted via optical transmission links of the radio-based transmission unit and the optical transmission unit, so that the various signals, which have different frequency bands, can be transmitted directly as optical transmission signals for environmental detection, or indirectly as electrical signals through conversion and / or manipulation. This makes it possible to provide a sensor system that can be used as both a LIDAR and a radar system.

[0039] In one embodiment, it is further provided that the sensor system comprises a receiving device having at least one radio-based receiving unit for receiving at least one electrical received signal. In addition, the receiving device can comprise at least one mixer with which a frequency band of the at least one electrical received signal can be varied. Furthermore, the sensor system comprises a computing device configured to process the electrical received signal. Electrical signals, such as the at least one electrical received signal, can be received using the radio-based receiving unit.

[0040] For example, the at least one electrical received signal may be a signal corresponding to one of the plurality of electrical transmitted signals.

[0041] In particular, the electrical transmission signals are emitted into the environment, and when they hit an object, a reflected signal can be reflected back. This can, for example, be the electrical reception signal. In particular, the electrical reception signal contains environmental information, especially radar information.

[0042] For example, for each electrical transmission signal transmitted, a corresponding electrical reception signal reflected in the environment can be received by the transmitting device.

[0043] The at least one received electrical reception signal or the plurality of received electrical reception signals can be processed accordingly and, for example, changed, in particular up-mixed or down-mixed, in its frequency band using the at least one mixer or a frequency manipulator.

[0044] The computing device can, in particular, be a central computing device. The computing device can, for example, be connected or coupled to the transmitting device and / or receiving device via signal or data transmission. The receiving device can have corresponding outputs and inputs so that, for example, the received electrical signals from the computing device can be transmitted, allowing the respective signals to be evaluated or processed. This allows for environmental detection.

[0045] For example, the central processing of data, signals and information, particularly with regard to environmental detection, takes place in the central computing facility.

[0046] For example, the transmitting device and / or the receiving device can be controlled using the computing device. In particular, the computing device can be used as a control and evaluation unit of the sensor system, and in particular for the transmitting device and the receiving device. Accordingly, for example, a wide variety of transmitting devices and / or receiving devices can be controlled, operated, or activated using one and the same central computing device.

[0047] The computing device can be coupled to the transmitting device and / or receiving device via one or more optical fibers and / or electrical lines.

[0048] In one exemplary embodiment, the receiving device comprises at least one optical receiving unit for receiving an optical received signal, wherein the computing device is designed to process the optical received signal and, in particular, the receiving device comprises an optical demodulator for demodulating the optical received signal. Consequently, the sensor system can be used as a LIDAR-radar combination system. In addition to the radio-based receiving unit, the receiving device can comprise at least one optical receiving unit or optical receiving device. With the aid of the optical receiving unit, an optical signal can be received which corresponds, for example, to one of the several directly emitted optical transmission signals. Thus, the sensor system also comprises a LIDAR measuring principle as a measuring principle in addition to a radar measuring principle.

[0049] The optical receiving unit can, for example, be integrated with the radio-based receiving unit in or on the receiving device. It is also conceivable for the optical receiving unit and the radio-based receiving unit to be separate units of the receiving device.

[0050] Furthermore, the receiving device can have a plurality of optical receiving units so that corresponding received optical signals can be received in an analogous manner to the plurality of transmitted optical transmission signals.

[0051] The optical demodulator can recover a useful signal, for example, the baseband carrier signal that was previously modulated onto a carrier. Specifically, an in-phase quadrature phase method (I&Q method) can be used, which allows phase information to be obtained during demodulation of a high-frequency carrier signal.

[0052] Additionally or instead, the receiving device can have at least one optical-electronic converter unit, with which an optical output signal can be modulated based on at least one of the plurality of optical transmission signals and the at least one electrical reception signal. In the optical-electronic converter unit or optical-electronic converter device, which can be referred to as a detector, for example, the at least one received electrical reception signal and at least one of the optical transmission signals can be modulated. Thus, in addition to at least one electrical reception signal, a corresponding optical transmission signal can also be supplied to the optical-electronic converter unit, so that an optical output signal can be generated by modulation.This in turn can contain environmental information so that this optical output signal of the computing device can be transmitted for further evaluation or processing.

[0053] In particular, the optical-electronic converter unit can be supplied with an electrical reception signal and an optical transmission signal which at least substantially have the same frequency band.

[0054] In one embodiment, the sensor system comprises a further optical device for generating a further optical carrier signal. Furthermore, the sensor system comprises a further electro-optical modulator, which is designed to generate a plurality of optical signals based on the further optical carrier signal such that the plurality of optical signals have different frequency bands from one another. In addition, the sensor system comprises at least one optical-to-electronic converter unit of the receiving device, with which an optical output signal can be modulated based on at least one of the plurality of optical signals and the at least one electrical received signal.Thus, the multiple optical output signals of the electro-optical modulator can optionally be dispensed with for generating or modulating the optical output signal, since the receiving device is supplied with various optical signals from another broadband optical source, which have different frequency bands relative to one another.

[0055] With the aid of the optical device, which can be referred to, for example, as an optical source, the receiving device can be supplied with a further optical carrier signal. The further optical transmission signal can be identical to the optical carrier signal. The further electro-optical modulator can be designed similarly to the electro-optical modulator already mentioned. A further aspect of the invention relates to a method for operating a sensor system according to the preceding aspect or an advantageous development thereof. The electro-optical modulator is operated in a specific operating mode, wherein in the specific operating mode of the electro-optical modulator, the plurality of optical transmission signals are generated such that the plurality of optical transmission signals have different frequency bands from one another.

[0056] In particular, the method just described can be used to operate a previously described sensor system. The electro-optical modulator can be operated at an operating point where as many harmonics of possibly identical amplitudes as possible can be generated. This allows different frequency bands to be generated with one electro-optical modulator. This allows the sensor system to be used more extensively, particularly for better environmental detection.

[0057] In one embodiment of the further aspect (method), it is provided that the electro-optical modulator is operated in the specific operating mode by defining the Nyquist point as the operating point of the electro-optical modulator. This consequently allows multiple harmonic signals to be generated. In particular, the Nyquist point offers the advantage that the multiple optical transmission signals are in phase with each other. Thus, stable signals can be generated and transmitted for environmental detection.

[0058] A further aspect of the invention relates to a motor vehicle with a sensor system according to the previous aspect or an advantageous development thereof. In particular, the motor vehicle just described includes a sensor system according to the previous aspect.

[0059] In particular, the motor vehicle is an assisted or at least partially autonomous vehicle. In particular, the motor vehicle is a highly automated vehicle that includes various driver assistance systems. These driver assistance systems can access the proposed sensor system and, for example, retrieve environmental information. In particular, the motor vehicle can have several such sensor systems.

[0060] In particular, multiple transmitting devices and multiple receiving devices can be arranged in and / or on the motor vehicle. These, in turn, can be coupled to the central computing device, which is, for example, centrally integrated in the motor vehicle.

[0061] The motor vehicle according to the invention is preferably designed as a motor vehicle, in particular as a passenger car or truck, or as a passenger bus or motorcycle. Furthermore, trams, subways, trains, boats, aircraft, satellites, and other mobile units can also be equipped with this sensor technology.

[0062] For example, the units of the sensor system can be distributed throughout the motor vehicle, particularly for environmental detection. In particular, the sensor system can be an environmental detection system.

[0063] Such a sensor system can be used in particular in motor vehicles, rail vehicles, watercraft, or automated systems, or in aeronautical or aerospace engineering. In particular, the sensor system can be used for environmental sensing or for detecting objects or environmental pollution.

[0064] Embodiments of individual aspects of the invention are to be regarded as advantageous embodiments of other aspects, in particular of all other aspects. In particular, the respective embodiments of individual aspects can be regarded as advantageous embodiments of all other aspects, and vice versa.

[0065] An environmental sensor system can be understood, for example, as a sensor system capable of generating sensor data or sensor signals that map, represent, or reproduce the environment of the environmental sensor system. In particular, the ability to detect electromagnetic or other signals from the environment is not sufficient for a sensor system to be considered an environmental sensor system. For example, cameras, radar systems, lidar systems, and / or ultrasonic sensor systems can be considered environmental sensor systems.

[0066] The invention also includes further developments of the motor vehicle according to the invention and the method according to the invention that have features already described in connection with the further developments of the sensor system according to the invention. For this reason, the corresponding further developments of the motor vehicle according to the invention and the method according to the invention are not described again here. The invention also encompasses combinations of the features of the described embodiments.

[0067] Exemplary embodiments of the invention are described below. Shown are:

[0068] Fig. 1 is a schematic representation of a motor vehicle having a sensor system according to the invention;

[0069] Fig. 2 is a schematic representation of a computing device and a transmitting device of the sensor system from Fig. 1;

[0070] Fig. 3 is a schematic representation of the transmitting device from Fig. 2, which additionally has an optical transmitting device;

[0071] Fig. 4 is a schematic representation of a receiving device of the sensor system 2 from Fig. 1;

[0072] Fig. 5 is a schematic representation of a further embodiment of the receiving device of the sensor system 2 from Fig. 1; and

[0073] Fig. 6 is a schematic representation of another embodiment of the receiving device of the sensor system 2 from Fig. 1.

[0074] The exemplary embodiments explained below are preferred exemplary embodiments of the invention. In the exemplary embodiments, the described components each represent individual, independently considered features of the invention, which also further develop the invention independently of one another and are thus also to be considered as components of the invention, either individually or in a combination other than that shown. Furthermore, the described exemplary embodiments can also be supplemented by further features of the invention already described.

[0075] In the figures, functionally identical elements are provided with the same reference numerals.

[0076] The invention will be described in more detail below with reference to the figures. It should be noted that various aspects are described, each of which can be used individually or in combination. This means that any aspect can be used with different embodiments of the invention unless explicitly presented as a mere alternative.

[0077] Furthermore, for the sake of simplicity, reference will generally only be made to one entity in the following. Unless explicitly stated, the invention may also comprise several of the entities in question. Therefore, the use of the words "a," "an," and "another" is to be understood merely as an indication that at least one entity is used in a simple embodiment.

[0078] Where procedures are described below, the individual steps of a procedure can be arranged and / or combined in any order, unless the context explicitly indicates otherwise. Furthermore, the procedures can be combined with one another unless expressly indicated otherwise.

[0079] Numerical values ​​are generally not to be understood as exact values, but also include a tolerance of + / - 1% to + / - 10%.

[0080] References to standards or specifications are to be understood as references to standards or specifications that are / were in force at the time of the application and / or, if priority is claimed, at the time of the priority application. However, this does not imply a general exclusion of applicability to subsequent or replacing standards or specifications.

[0081] Fig. 1 shows a schematic plan view of an embodiment of a motor vehicle 1. The motor vehicle can be designed, for example, as a highly automated vehicle or as an at least partially autonomously operated vehicle.

[0082] The motor vehicle 1 can, for example, have a sensor system 2. With the help of the sensor system 2, an environment 3 of the motor vehicle 1 can be detected. For example, the sensor system 2 can be part of a driver assistance system of the motor vehicle 1. In particular, the sensor system 2 provides corresponding information, in particular regarding the environment 3, for the driver assistance system or a vehicle guidance system. In addition to the use of the sensor system 2 in the motor vehicle 1, it can also be used in systems external to the vehicle. For example, the sensor system 2 can be used in automated systems, in space technology, in aviation technology, or in communications technology.

[0083] In Fig. 1, the example in which the sensor system 2 is integrated in the motor vehicle 1 is shown again for illustrative purposes.

[0084] In Fig. 2, one of several embodiments of the sensor system 2 is shown by way of example in a representation, in particular in a block diagram.

[0085] Here, Fig. 2 shows, by way of example, a transmitting device 4 and a computing device 5 of the sensor system 2. The computing device 5 serves in particular for signal processing, signal processing, and / or signal evaluation for the sensor system 2.

[0086] The computing device 5 can, for example, be a central unit or a central control or central activation unit of the sensor system 2.

[0087] The sensor system 2 comprises, in particular, an optical device 6, with which an optical carrier signal 7 or an optical transmission signal can be provided or generated. The optical device 6 can be integrated into the computing device 5, as shown by way of example in Fig. 2.

[0088] The optical device 6 can, for example, be a laser device or an optical source.

[0089] In the illustrated Fig. 2, the optical device 6 is integrated into the computing device 5. However, this is only one possible example. The optical device 6 can also be designed as a standalone unit.

[0090] The sensor system 2 can have an electro-optical modulator 8, which is, for example, integrated or arranged in the computing device 5. Using the electro-optical modulator 8, a plurality of optical transmission signals 9 (shown here in a simplified manner) can be generated based on the optical carrier signal 7. In particular, the electro-optical modulator 8 is designed such that radar ramps or radar signals or transmission signals can be realized in different bands or frequency bands. Accordingly, the sensor system requires only a single electro-optical modulator 8 for this purpose. To achieve this, the electro-optical modulator 8 is operated at a predetermined or specific operating point.In this case, an operating point is driven or controlled by generating as many harmonics as possible, i.e., harmonic oscillations whose frequency is an integer multiple of a fundamental frequency. The fundamental frequency can, in turn, be provided by the optical carrier signal 7. These harmonics can have an identical amplitude. To achieve this particularly advantageously, the Nyquist point can be used as the operating point 10.

[0091] Based on the operating point 10 and the optical carrier signal 7, the multiple optical transmission signals 9 can be generated such that the multiple optical transmission signals 9 have different frequency bands from one another. For this purpose, the electro-optical modulator 8 can optionally be additionally modulated with a high-frequency signal 11. This can primarily be an RF signal.

[0092] For environmental detection, the sensor system 2 has at least one transmitting device 4, which has at least one radio-based transmitting unit 12. In this exemplary embodiment, three or more radio-based transmitting units 12, 13, 14 are shown. The radio-based transmitting unit 12, 13, 14 can be a unit or device based on a radar sensor.

[0093] The generated multiple optical transmission signals 9 can be transmitted or sent, for example, via optical transmission links, such as via fiber optics, to the transmitting device 4 or other transmitting devices of the sensor system 2.

[0094] The transmitting device 4 can, for example, have at least one optical-electronic converter unit 15. This converter unit 15 serves for the optoelectronic conversion of the multiple optical transmission signals 9 into multiple electrical transmission signals 16, 17, 18. After conversion, the electrical transmission signals 16, 17, 18 can be separated accordingly by means of a distributor 19, in particular according to their frequency band. The distributor 19 can, for example, be a "1x3 power divider." Furthermore, a narrowband optoelectronic converter or an electrical bandpass filter can be used as the distributor 19. Following the distributor 19, the electrical transmission signals 16, 17, 18 can be separated or divided according to their frequency bands 20, 21, 22.For example, the electrical transmission signals 16, 17, 18 and also the multiple optical transmission signals 9 can be coherent with each other and, in particular, in phase with each other. Accordingly, the proposed sensor system 2 can be operated or used by simultaneously or synchronously measuring on several different frequency bands, as shown in Fig. 2, on three different frequency bands. This is particularly advantageous for location classification with regard to environmental detection.

[0095] After the electrical transmission signals 16, 17, 18 have been separated, they can each be modified, in particular up-mixed, in their respective frequency bands 20, 21, 22 using a frequency manipulator 23, 24, 25 or a frequency mixer. Furthermore, the respective frequency bands 20, 21, 22 can then be amplified or boosted using a respective electrical amplifier 26, 27, 28. After the electrical transmission signals 16, 17, 18 have been up-mixed and amplified, they can be transmitted or radiated into the environment 3 for environmental detection using a respective radio-based transmission unit 16, 17, 18, which can be referred to, for example, as antennas.

[0096] For example, the transmitting device 4 can be referred to as a transmitting module. The transmitting device 4 can be controlled or operated, for example, using the computing device 5, so that at least one radar-based signal, i.e., signals 16, 17, 18, can be transmitted. In particular, the embodiment in Fig. 2 shows the use of the sensor system 2 as a radar system. A multi-band radar can be created using the electro-optical modulator 8 according to the invention. In particular, this can be referred to as a "Nyquist pulse multi-band radar."

[0097] The computing device 5 can be a spatially and / or physically separate unit from the transmitting device 4. In this case, the computing device 5 and the transmitting device 4 can be connected via multiple optical transmission paths or optical transmission links in order to be able to exchange or transmit the optical signals. In a further embodiment, it can also happen that the transmitting device 4 and the computing unit 5 are integrated into a common unit. Fig. 2, for example, shows that the different frequency bands 20, 21, 22 of the transmitted signals can be transmitted using one transmitting device 4. It is also conceivable that a separate transmitting device 4 is used for each transmitted signal or frequency band.

[0098] In particular, depending on the application, the sensor system 2 can be designed or configured accordingly.

[0099] Fig. 3 shows a further embodiment of the sensor system 2, the use of the sensor system 2 as a LIDAR-radar combination system. With regard to the generation of the multiple optical transmission signals 9 and the transmission of the multiple electrical transmission signals 16, 17, 18, reference is again made to the explanations in Fig. 2. The embodiment in Fig. 3 differs from the embodiment in Fig. 2 in that the sensor system 2 additionally has at least one optical transmission unit 29. This optical transmission unit 29 can, in particular, be a LIDAR-based sensor. With the aid of the optical transmission unit 29, at least one of the multiple optical transmission signals 9 can be transmitted directly for environmental detection.After generating the multiple optical transmission signals 9, the optical transmission signals 9 can be distributed or branched by an optical unit 30, which can be configured, for example, as a "1x2 splitter." Thus, the optical transmission signals 9 can be transmitted to the radio-based transmission units 12, 13, 14 for conversion into the electrical transmission signals 16, 17, 18, as already explained in Fig. 2. Additionally, the optical transmission signals 9 can be transmitted to the at least one optical transmission unit 29 or to further optical transmission units.

[0100] For example, the optical transmission unit 29 can be a component of the transmission device 4. It is also conceivable that the optical transmission unit 29 is designed separately from the transmission device 4.

[0101] Thus, with the embodiment in Fig. 3, a combination of a radar system and a LIDAR system can be implemented, namely with the sensor system 2. Joint control and evaluation can be carried out with the aid of the computing device 5. Furthermore, radar and LIDAR signals, or the radio-based signals and the optical-based signals, can be coherent with one another, and combined signal processing for the transmitting units 12, 13, 14, 29 can be provided with the aid of the computing device 5. Fig. 4 shows an embodiment of a receiving device 31 of the sensor system 2. For example, the receiving device 31 can be combined with the transmitting device 4. In this case, these can be at least partially integrated into one device.For example, the transmitting device 4 and the receiving device 31 can be combined by means of interchangeable or controllable components, so that, for example, it is possible to switch between a receiving mode and a transmitting mode as required.

[0102] The receiving device 31 can have at least one radio-based receiving unit 32, 33, 34. These can be radar-based receiving units. Using the radio-based receiving units 32, 33, 34, at least one electrical received signal 35, 36, 37 can be received. The received signal or signals 35, 36, 37 can be signals corresponding to the electrical transmission signals 16, 17, 18 and reflected in the environment 3.

[0103] In particular, the transmitting device 4 and the receiving device 31 can be complementary to each other.

[0104] For example, the received electrical signals 35, 36, 37 can be down-mixed using at least one mixer 38, 39, 40. This involves, in particular, changing or adapting the respective frequency band of the received signals 35, 36, 37. Additionally, depending on the signal strength of the received signals 35, 36, 37, they can be amplified using a respective amplifier 41, 42, 43. The electrical signals 35, 36, 37 can then be provided at electrical outputs. In this case, they can be transmitted, in particular, to the computing device 5 or another evaluation or processing unit.

[0105] In Fig. 5, an extension of the receiving device 31 from Fig. 4 is shown in a further embodiment.

[0106] In the embodiment in Fig. 5, the receiving device 31 is particularly designed such that optical retransmission can take place. In this case, the multi-band optical transmission signals 9 can be split again into the individual optical carriers or the individual frequency bands by means of optical filters 44, 45, 46. For this purpose, the optical transmission signals 9 can in turn be split or selected via a unit 59, for example a "1x4 power splitter". For example, the optical filters 44, 45, 46 can use a time-of-flight method, such as "Time-of-Flight (ToF)". The split and thus filtered transmission signals 9 can then be modulated on or with the received electrical reception signals 35, 36, 37. For this purpose, at least one optical-electronic converter unit 47, 48, 49 can in turn be used.Thus, for example, an optical output signal 50 is modulated here based on the transmitted signals 9 and the received signals 35, 36, 37. For this purpose, after the processes of the converter units 47, 48, 48, the signals can be combined using a unit 51, such as a "1x3 power combiner," so that the optical output signal 50 can be provided, for example, at an optical output. This can, in turn, be made available or transmitted to the computing device 5 or another processing unit.

[0107] Fig. 6 shows an alternative to the receiving device 31 in Fig. 5. Here, again, a receiving circuit with an optical output is shown as in Fig. 5, although here the respective frequency bands of a further broadband optical source are used. For this purpose, a further optical device 52 can be used. This can generate a further optical carrier signal 53. The carrier signal 53 can again be the same as the carrier signal 7. The further optical device 52 can be a further optical source. By means of a further electro-optical modulator 54, which can, for example, be identical to the electro-optical modulator 8, a plurality of optical signals 55, 56, 57 can be generated on the basis of the carrier signal 53. Thus, the carrier signal 53 can again be divided into a plurality of bands or frequency bands.A distributor 58, such as a "1x3 power splitter," can be used for this purpose. The modulator 54 can also be operated at operating point 10, similar to modulator 8. The bands or frequency bands of the signals 55, 56, 57 can then be divided again using the optical filters 44, 45, 46 and subsequently modulated. The converter units 47, 48, 48 can again be used for this purpose. Thus, the optical output signal can be generated by modulation based on the optical signals 55, 56, 57 and the received electrical signals 35, 36, 37.

[0108] Another alternative to device 52 would be the use of a broadband optical source. It is also conceivable to modulate the light from one or more optical sources separately for each received signal 35, 36, 37.

[0109] Furthermore, for use as a combined LIDAR-radar system, the sensor system 2 can have at least one optical receiving unit for receiving an optical received signal. This optical received signal can correspond to a directly transmitted transmitted signal 9. For this purpose, the computing device 5 can in turn be configured to process the optical received signal. Furthermore, the optical received signal can be demodulated using an optical demodulator.

[0110] The embodiments in Figs. 2 to 6 can be combined with each other in various ways depending on the application or area of ​​application of the sensor system 2.

[0111] In particular, the computing device 5, the transmitting device 4, and the receiving device 31 can be physically and / or spatially separate units. Alternatively, the transmitting device 4, the receiving device 31, and the computing device 5 can be formed together as a common unit.

[0112] List of reference symbols

[0113] Motor vehicle sensor system environment transmitting device computing device optical device optical carrier signal electro-optical modulator multiple optical transmission signals operating point

[0114] High-frequency signal, 13, 14 radio-based transmitting unit, optical-electronic converter unit, 17, 18 several electrical transmission signals

[0115] Distributor, 21, 22 Frequency bands, 24, 25 Frequency manipulator, 27, 28 Amplifier Optical transmitting unit Optical unit Receiving device, 33, 34 Radio-based receiving unit, 36, 37 Electrical received signals, 39, 40 Mixer, 42, 43 Amplifier, 45, 46 Optical filters, 48, 49 Optical-electronic converter unit Optical output signal unit Further optical device Further optical carrier signal Further electro-optical modulator 55, 56, 57 Several optical signals

[0116] 58 distributors

[0117] 59 distributors

Claims

Patent claims 1. Sensor system (2) for environment detection, with - an optical device (6) for generating an optical carrier signal (7), - a transmitting device (4) which is designed to transmit electrical transmission signals (16, 17, 18) which are based on the optical carrier signal (7), characterized by - an electro-optical modulator (8) having a predetermined operating point (10), - the electro-optical modulator (8), which is designed to generate a plurality of optical transmission signals (9) on the basis of the predetermined operating point (10) and the optical carrier signal (7) in such a way that the plurality of optical transmission signals (9) have different frequency bands (20, 21, 22) from one another, and - the transmitting device (4), which is designed to convert the plurality of optical transmission signals (9) into a plurality of electrical transmission signals (16, 17, 18) and to transmit the plurality of electrical transmission signals (16, 17, 18) with at least one radio-based transmission unit (12, 13, 14).

2. Sensor system (2) according to claim 1, characterized in that the electro-optical modulator (8) is designed to additionally take into account a high-frequency signal (11) provided to the electro-optical modulator (8) for generating the plurality of optical transmission signals (9).

3. Sensor system (2) according to claim 1 or 2, characterized in that - the transmitting device (4) has at least one optical-electronic converter unit (15) with which the plurality of optical transmission signals (9) can be converted into the plurality of electrical transmission signals (16, 17, 18), and / or - the transmitting device (4) has at least one frequency manipulator (23, 24, 25) with which at least one frequency band (20, 21, 22) of one of the plurality of electrical transmission signals (16, 17, 18) can be changed, and / or - the transmitting device (4) has at least one electrical amplifier (26, 27, 28) for amplifying at least one frequency band (20, 21, 22) of one of the plurality of electrical transmission signals (16, 17, 18).

4. Sensor system (2) according to one of the preceding claims, characterized by an optical transmission unit (29) of the transmission device (4), which is designed to transmit at least one of the plurality of optical transmission signals (9) directly.

5. Sensor system (2) according to one of the preceding claims, characterized by - a receiving device (31) which has at least one radio-based receiving unit (32, 33, 34) for receiving at least one electrical received signal (35, 36, 37), in particular the receiving device (31) has at least one mixer (38, 39, 40) with which a frequency band (20, 21, 22) of the at least one electrical received signal (35, 36, 37) can be changed, and - a computing device (5) which is designed to process the electrical received signal (35, 36, 37).

6. Sensor system (2) according to claim 5, characterized in that - the receiving device (31) has at least one optical receiving unit for receiving an optical reception signal, wherein the computing device (5) is designed to process the optical reception signal, in particular the receiving device (31) has an optical demodulator for demodulating the optical reception signal, and / or - the receiving device (31) has at least one optical-electronic converter unit with which an optical output signal (50) can be modulated on the basis of at least one of the plurality of optical transmission signals (9) and the at least one electrical reception signal (35, 36, 37).

7. Sensor system (2) according to claim 5, characterized by - a further optical device (52) for generating a further optical carrier signal (53), - a further electro-optical modulator (54) which is designed to generate a plurality of optical signals (55, 56, 57) on the basis of the further optical carrier signal (53) in such a way that the plurality of optical signals (55, 56, 57) have different frequency bands (20, 21, 22) from one another, and - at least one optical-electronic converter unit (47, 48, 49) of the receiving device (31), with which an optical output signal (50) can be modulated on the basis of at least one of the plurality of optical signals (55, 56, 57) and the at least one electrical received signal (35, 36, 37).

8. A method for operating a sensor system (2) according to one of the preceding claims, wherein - the electro-optical modulator (8) is operated in a specific operating mode, wherein in the specific operating mode of the electro-optical modulator (8) the plurality of optical transmission signals (9) are generated such that the plurality of optical transmission signals (9) have mutually different frequency bands (20, 21, 22).

9. The method according to claim 8, characterized in that the electro-optical modulator (8) is operated in the specific operating mode in such a way that the Nyquist point is defined as the operating point (10) of the electro-optical modulator (8).

10. Motor vehicle (1) with a sensor system (2) according to one of the preceding claims 1 to 7.

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