Method and device for detecting the surroundings by means of a group of radar sensors

Abstract

The invention relates to a device for determining a set of detection points by means of a first radar sensor and a second radar sensor of a vehicle, the device being designed to acquire, in a calibration phase, pose information with regard to a relative pose between the first radar sensor and the second radar sensor on the basis of calibration signals transmitted from the first radar sensor to the second radar sensor. The device is also designed to collect a combined set of detection points with regard to the surroundings of the vehicle on the basis of the first radar sensor and the second radar sensor and using the pose information.

Description

[0001] 24-2002

[0002] Method and device for environmental sensing using a group of

[0003] Radar sensors

[0004] The invention relates to a method and a corresponding device designed to acquire environmental data relating to the environment of a vehicle using a group of radar sensors.

[0005] A vehicle can have one or more driving functions, each configured to automatically guide the vehicle longitudinally and / or laterally. In this context, the vehicle typically includes one or more environmental sensors, each configured to acquire sensor data relating to the vehicle's surroundings, for example, to detect one or more objects in the vehicle's vicinity. The automated longitudinal and / or lateral guidance of the vehicle can be triggered based on the one or more detected objects.

[0006] The vehicle may have a radar sensor as an environmental sensor, which is configured to capture a set of detection points over a specific measurement period, where each detection point may correspond to a reflection of a (radar) transmission signal sent by the radar sensor from an object. The radar sensor typically has a 24-2002

[0007] - 2 - limited aperture and as a consequence a limited spatial resolution of the detection points.

[0008] The spatial resolution of a radar sensor can be increased by increasing the number of transmitting and / or receiving antennas of the radar sensor, but this leads to a larger size of the radar sensor, making it more difficult to install the radar sensor in a vehicle.

[0009] Alternatively or additionally, the spatial resolution can be increased by the combined and / or coordinated use of a group of several (relatively small) radar sensors (i.e., by a so-called "Distributed Aperture Radar").

[0010] This document addresses the technical task of determining a particularly precise combined set of detection points (especially a combined point cloud) for the group of radar sensors.

[0011] The problem is solved by each of the independent claims. Advantageous embodiments are described, inter alia, in the dependent claims. It should be noted that additional features of a claim dependent on an independent claim, without the features of the independent claim itself or only in combination with a subset of the features of the independent claim, may constitute a separate invention independent of the combination of all features of the independent claim, which may be the subject of an independent claim, a divisional application, or a subsequent application. This applies equally to technical teachings described in the description, which may constitute an invention independent of the features of the independent claims. 24-2002

[0012] - 3 -

[0013] According to one aspect, a device for determining a set of detection points is described using a first and a second radar sensor of a vehicle. The radar sensors can be arranged at different locations on the vehicle.

[0014] The device can be configured to operate the first radar sensor and the second radar sensor in a coherent and / or synchronized manner to determine a combined set of detection points, wherein the combined set of detection points typically has a spatial resolution greater than the spatial resolution of the sets of detection points that can be detected individually by the first or by the second radar sensor.

[0015] Each radar sensor can have transmitting antennas (e.g., N transmitting antennas) and receiving antennas (e.g., M receiving antennas) arranged in a defined manner within the respective radar sensor. The device can be configured to cause the transmitting antennas of the first and second radar sensors to emit signals in a coherent and / or synchronized manner during a measurement period. The measurement period can be, for example, 100 ms or less.

[0016] Furthermore, received signals based on the transmitted signals can be received via the receiving antennas of the first and second radar sensors. These received signals, particularly their phases, can be evaluated together to determine a combined set of detection points for the respective measurement period. The relative position between the first and second radar sensors can be taken into account (to determine and consider the overall arrangement of the transmitting and receiving antennas of the first and second radar sensors during evaluation). 24-2002

[0017] - 4 -

[0018] The relative position between the first and second radar sensors can change during vehicle operation (e.g., due to vibrations and / or external influences such as wind). The device described in this document is designed to determine position information regarding the current relative position between the first and second radar sensors and to take this information into account when determining the combined set of detection points. This allows the spatial resolution of the radar sensors to be increased in a particularly precise and robust manner.

[0019] The device is designed to determine, during a calibration phase (which precedes the measurement period), pose information regarding the (current) relative pose between the first radar sensor and the second radar sensor, based on calibration signals sent from the first radar sensor to the second radar sensor.

[0020] The device can be configured, in particular, to cause N transmitter units of the first radar sensor to each send a calibration signal to the second radar sensor during the calibration phase, with N > 3. The N calibration signals can be sent and / or conducted via one or more, in particular metallic, components of the vehicle (e.g., via a (hollow) support of the vehicle).

[0021] The N calibration signals can be received via M receiver units of the second radar sensor, with M>3. The pose information can be determined precisely based on the N calibration signals received via the M receiver units, i.e., in particular based on the N x M received signals.

[0022] The device can be set up, in the calibration phase, based on the N calibration signals received via the M receiving units 24-2002

[0023] - 5 -

[0024] (especially based on the N x M received signals), to determine a multitude of transmission path measurements. The multitude of transmission path measurements can, in particular, include N x M transmission path measurements for the corresponding N x M combinations of one transmitting unit of the first radar sensor and one receiving unit of the second radar sensor (i.e., for the corresponding N x M received signals).

[0025] The individual transmission path measurements can each indicate the transit time and / or the phase of a calibration signal received by a receiving unit and / or the length of the transmission path between a transmitting unit and a receiving unit.

[0026] Pose information can be determined with exceptional precision based on a multitude of transmission path measurements. The device can be configured to determine the pose information based on these measurements using a pre-defined vehicle model and / or a triangulation method. The vehicle model can be a machine-learning model. Alternatively or additionally, the vehicle model can include an assignment function that assigns different relative poses to different combinations of values ​​from the multitude of transmission path measurements. The vehicle model typically depends on the type or design of the vehicle. The vehicle model may have been experimentally determined beforehand (for the respective vehicle type).

[0027] The device is further configured to acquire a combined set of detection points in relation to the vehicle's surroundings for a measurement period (following the calibration phase) using the first radar sensor, the second radar sensor, and pose information. The combined set of detection points can be determined as described above. The data obtained from the 24-2002

[0028] - 6 -

[0029] The (current) relative pose between the first and second radar sensors is taken into account in the pose information. This allows for the determination of a particularly precise combined set of detection points.

[0030] The relative position between the first radar sensor and the second radar sensor can be described by one or more parameters. Examples of such parameters are:

[0031] • the distance between the first and second radar sensors (in the x, y and / or z direction of a Cartesian coordinate system); and / or

[0032] • a rotation between the first and second radar sensors (around the x, y and / or z axis of the Cartesian coordinate system).

[0033] The determined pose information can specify current values ​​for one or more of the aforementioned parameters, in particular for all of them.

[0034] The device can be configured to cause the N transmitter units to send the N calibration signals in the same frequency band (e.g., 76-77 GHz) used for determining the number of detection points. The N calibration signals can be sent in a time slot that is not used for determining the number of detection points. This enables particularly efficient and precise determination of pose information.

[0035] Alternatively, the device can be configured to cause the N transmitter units to send the N calibration signals in a frequency band (e.g., 77–81 GHz) that differs from the frequency band (e.g., 76–77 GHz) used for acquiring the number of detection points. This allows for particularly flexible and precise determination of pose information. 24-2002

[0036] - 7 -

[0037] The N transmitting units and the M receiving units (for the calibration signals) can each include (transmitting or receiving) antennas that are also used to determine the number of detection points. This enables particularly efficient and precise determination of pose information. Alternatively, the N transmitting units and the M receiving units can each include at least one dedicated component, in particular a 6G transmitter or a 6G receiver, that is not used to determine the number of detection points. This enables particularly flexible and precise determination of pose information.

[0038] The device can be configured to determine pose information regarding the current relative pose between the first and second radar sensors in each successive calibration phase. The frequency of the calibration phases can be matched to the expected frequency of changes in the relative pose between the first and second radar sensors (and is preferably higher than the expected frequency of changes in the relative pose).

[0039] Furthermore, the device can be configured to determine the pose information used to calculate the combined set of detection points for a measurement period by interpolation and / or (Kalman) filtering and / or extrapolation of the pose information obtained for the sequence of successive calibration phases. Pose information for the relative pose between the first and second radar sensors during the measurement period can be determined. This further increases the accuracy of the calculated combined set of detection points. 24-2002

[0040] - 8 -

[0041] The device can be configured to determine, for each measurement period of a sequence of successive measurement periods, pose information relating to the current pose between the first radar sensor and the second radar sensor for (in particular during) the respective measurement period. The pose information can be determined, for example, by interpolation and / or extrapolation and / or filtering (as explained above).

[0042] The device can further be configured to acquire a combined set of detection points in relation to the vehicle's surroundings for each measurement period, using the first radar sensor, the second radar sensor, and the pose information. By using up-to-date pose information, consistently precise sets of detection points can be determined.

[0043] The device can be configured to detect at least one object in the vehicle's vicinity based on the combined set of detection points. Alternatively or additionally, the device can be configured to automatically guide the vehicle longitudinally and / or laterally based on the combined set of detection points. This further enhances the effectiveness of a driving function for automated longitudinal and / or lateral vehicle guidance.

[0044] According to another aspect, a (road) motor vehicle (in particular a passenger car or a truck or a bus or a motorcycle) is described that includes the device described in this document.

[0045] According to one aspect, a method for determining a set of detection points using a first and a second radar sensor of a (motor) vehicle is described. The method includes determining, in a calibration phase, using calibration signals sent from the first radar sensor to the second radar sensor, Poseinformation 24-2002.

[0046] - 9 - with respect to the relative pose between the first radar sensor and the second radar sensor. Furthermore, the method comprises acquiring and / or determining, using the first radar sensor, the second radar sensor and the pose information, a combined set of detection points in relation to the vehicle's surroundings for a measurement period.

[0047] It should be noted that the aspects described in connection with the device, in particular the claims described in connection with the device, are also applicable to the method as corresponding process features.

[0048] Another aspect described is a software (SW) program. The SW program can be configured to run on a processor (e.g., on a vehicle's control unit) and thereby execute the procedure described in this document.

[0049] Another aspect describes a storage medium. This storage medium can include a software program configured to run on a processor and thereby execute the procedure described in this document.

[0050] It should be noted that the methods, devices, and systems described in this document can be used both alone and in combination with other methods, devices, and systems described in this document. Furthermore, any aspect of the methods, devices, and systems described in this document can be combined with one another in a variety of ways. In particular, the features of the claims can be combined with one another in a variety of ways. Features listed in parentheses are to be understood as optional features. 24-2002

[0051] - 10 -

[0052] The invention will now be described in more detail using exemplary embodiments.

[0053] Figure 1 shows exemplary components of a vehicle;

[0054] Figure 2a shows an exemplary group of radar sensors;

[0055] Figure 2b shows exemplary transmission paths between different radar sensors of a group of radar sensors;

[0056] Figure 2c shows exemplary transmission paths when using radar sensors with dedicated (additional) transmitting and / or receiving units;

[0057] Figure 3 shows an exemplary vehicle model; and

[0058] Figure 4 shows a flowchart of an exemplary procedure for determining a combined set of detection points using a group of radar sensors.

[0059] As stated at the outset, this document deals with the efficient improvement of the accuracy of a vehicle's environmental sensing. In this context, Fig. 1 shows an exemplary vehicle 100 with one or more environmental sensors 102, each configured to acquire sensor data (also referred to as environmental data) relating to the vehicle 100's surroundings. Examples of environmental sensors 102 include a camera, a radar sensor, a lidar sensor, an ultrasonic sensor, etc.

[0060] A (control) device 101 of the vehicle 100 can be configured to evaluate environmental data, e.g., to detect one or more objects (e.g., other vehicles) in the vicinity of the vehicle 100. The device 101 can further be configured to effect automated longitudinal and / or lateral control of the vehicle 100 based on the environmental data, in particular based on the one or more detected objects. For this purpose, one or more longitudinal and / or lateral control actuators 103 (e.g., a drive motor, a braking device, and / or a steering device) of the vehicle can be controlled. 24-2002

[0061] - 11 -

[0062] A radar sensor 102 of the vehicle 100 can be configured to transmit signals via an arrangement of transmitting antennas during a measurement period. These signals may be detected by an object. The transmitted signals reflected by an object can be received as receive signals by an arrangement of receiving antennas of the radar sensor 102. By evaluating the phases of the received signals (taking into account the geometry of the arrangement of transmitting and receiving antennas of the radar sensor 102), a set, in particular a frame, of detection points can be determined for the measurement period. Each individual detection point can correspond to a reflection point on an object in the vicinity of the vehicle 100. The individual detection points can each be specified as measured values.

[0063] • an angle (e.g. an azimuth angle and / or an elevation angle) of the detection point relative to the radar sensor 102 (in particular relative to the normal vector of the radar sensor 102);

[0064] • a (radial) distance of the detection point from the radar sensor 102; and / or

[0065] • a (radial) velocity of the detection point.

[0066] The spatial resolution of the detection points within a set of detection points typically depends on the aperture of the radar sensor, in particular on the size of the transmitting antenna array and / or the size of the receiving antenna array. Alternatively or additionally to using a relatively large radar sensor 102, a group of several (relatively small) radar sensors 102 can be used to increase the effective aperture and thus the spatial resolution of detection points. The individual (relatively small) radar sensors 102 can then be flexibly installed at different locations within a vehicle 100.

[0067] Fig. 2a shows an exemplary group of radar sensors 201, 202, with a first radar sensor 201 and with a second radar sensor 202. The 24-2002

[0068] - 12 -

[0069] Radar sensors 201, 202 of the group of radar sensors 201, 202 can be operated in a coordinated, in particular in a (temporally) synchronized, manner in order to acquire a combined set of detection points for a measurement period.

[0070] The first radar sensor 201 and the second radar sensor 202 each have an arrangement of transmitting antennas 211 and an arrangement of receiving antennas 212, as shown by way of example in Fig. 2b. During a measurement period, transmit signals can be synchronized (in time) from the transmitting antennas 211 of the first and second radar sensors 201, 202. Furthermore, received signals can be synchronized from the receiving antennas 212 of the first and second radar sensors 201, 202. The phases of the received signals acquired by the receiving antennas 212 of the first and second radar sensors 201, 202 can be evaluated (e.g., using a Fast Fourier Transform) to determine a set of detection points for the measurement period.

[0071] When evaluating the (phases of the) received signals, the spatial position of the first and second radar sensors 201, 202, i.e., the relative position 203 between the first and second radar sensors 201, 202, is typically taken into account. The relative position 203 between the first and second radar sensors 201, 202 can change during the operation of the vehicle 100, e.g., due to vibrations and / or environmental influences such as wind.

[0072] The device 101 for evaluating the received signals can be configured to determine the current relative position 203 between the first and second radar sensors 201, 202 for a specific measurement period. Furthermore, the device 101 can be configured to take the determined current relative position 203 into account when evaluating the (phases of) the received signals from the first and second radar sensors 201, 202. Thus, for the 24-2002

[0073] - 13 - for each individual measurement period, a particularly precise (combined) set of detection points (with a relatively high spatial resolution) is determined.

[0074] To determine the current relative position 203 between the first and second radar sensors 201, 202, calibration signals can be sent from the first radar sensor 201 to the second radar sensor 202 during a calibration phase. The individual calibration signals are transmitted from the first radar sensor 201 to the second radar sensor 202 via a transmission path 215, as illustrated by way of example in Figures 2b and 2c. The transmission path 215 can comprise a (metallic) component, e.g., a (cross)beam, of the vehicle 100.

[0075] The first radar sensor 201 can have N transmitting units 211, 221, and the second radar sensor 202 can have M receiving units 212, 222, preferably N>3 and / or M>3. The N transmitting units 211, 221 can correspond to individual transmitting antennas 211 of the first radar sensor 201, and / or the M receiving units 212, 222 can correspond to individual receiving antennas 212 of the second radar sensor 202 (as shown by way of example in Fig. 2b). Alternatively or additionally, the N transmitting units 211, 221 can correspond to dedicated transmitting units 212 (e.g. 6G transmit) of the first radar sensor 201, and the M receiving units 212, 222 can correspond to dedicated receiving units 222 (e.g. 6G receiver) of the second radar sensor 202 (as shown by way of example in Fig. 2c).

[0076] Between the first radar sensor 201 and the second radar sensor 202, N x M different transmission paths 215 for calibration signals can thus exist, wherein a transmission path 215 runs between exactly one of the N transmitting units 211, 221 of the first radar sensor 201 and exactly one of the M receiving units 212, 222 of the second radar sensor 202. The individual transmission paths 215 typically correspond (due to 24-2002)

[0077] - 14 -

[0078] Reflections of the calibration signal) indirect propagation paths between the first radar sensor 201 and the second radar sensor 202. As already explained, the individual transmission paths 215 can, for example, be formed essentially by a crossbeam of the vehicle 100.

[0079] During the calibration phase, signal propagation times (generally transmission path measurements) can be determined for the N x M transmission paths 215 by sending and receiving calibration signals. In particular, corresponding N x M signal propagation times (generally transmission path measurements) can be determined for the N x M transmission paths 215. The N x M signal propagation times (generally the transmission path measurements) depend on the current relative position 203 between the first and second radar sensors 201, 202.

[0080] In advance, a vehicle model 300 for a vehicle 100 (especially for a specific vehicle type) can be determined by measurements, as exemplified in Fig. 3. The vehicle model 300 can be configured to record a plurality of transmission path measurements 305 (e.g., N x M transmission path measurements), wherein the plurality of transmission path measurements 305 can, in particular, include the N x M signal propagation times. Furthermore, the vehicle model 300 can be configured to determine the relative position 203 between the first and the second radar sensors 201, 202 based on the plurality of transmission path measurements 305 (achieved by the combination of N x M transmission path measurements 305). The vehicle model 300 can, for example, include a neural network trained by machine learning.Alternatively or additionally, the vehicle model 300 can include a lookup table (generally an assignment function) that specifies a corresponding relative position 203 for a variety of different combinations of the N x M transmission path measurements 305. 24-2002.

[0081] - 15 -

[0082] During the operation of vehicle 100, the current relative position 203 between the first and second radar sensors 201, 202 can be determined in each sequence of successive calibration phases (using the described method). To determine the current relative position 203 for (measurement) times or for (measurement) periods between two directly consecutive calibration phases, an interpolation of several relative positions 203 from several calibration phases can be performed (e.g., using a Kalman filter). This is possible because the relative position 203 typically changes relatively slowly compared to the sequence of measurement periods used to determine detection points.

[0083] For environmental sensing, a (combined) set of detection points can be determined using radar sensors 201 and 202 during a sequence of successive measurement periods. The current relative position 203 between radar sensors 201 and 202 (possibly determined by interpolation) can be taken into account to determine the respective (combined) set of detection points. In this way, consistently precise (combined) sets of detection points can be determined with a relatively high spatial resolution.

[0084] As explained above, relatively large radar sensors 102 are typically difficult to integrate into a vehicle 100. However, relatively large apertures can be achieved through the coordinated use of several individual radar sensors 201, 202. This typically results in coherent operation of the individual radar sensors 201, 202 with respect to the phase angles of the transmit and receive antennas 211, 212 of the individual radar sensors 201, 202. This can be achieved by fixing the relative positions of the antennas 211, 212 of the radar sensors 201, 202 (e.g., by a mechanical connection between the radar sensors 201, 202). A mechanically fixed connection between the radar sensors 201, 202 24-2002

[0085] - 16 - however, this is usually not possible (especially if the radar sensors 201, 202 are installed relatively far apart).

[0086] As described in this document, the relative distance and, in particular, the sensor position 203 of the radar sensors 201, 202 (and thus the relative position of the individual antennas 211, 212 of the radar sensors 201, 202 in space) to each other can be measured and / or estimated online, i.e., during the operation of a vehicle 100. The relative position 203 can be determined with a calibration frequency (in a sequence of calibration phases), the calibration frequency being preferably higher than the expected frequency of the change in position 203. The change in position 203 can be caused by vibrations (e.g., from the engine, road irregularities, chassis movements, brake application, etc.) and / or by wind load (due to the driving wind).

[0087] The relative position 203 can be achieved by performing distance measurements (generally calibration measurements) of the individual antennas 211 of the first radar sensor 201 to the individual antennas 212 of the second radar sensor 202. Thus, N x M distance values ​​(or corresponding time-of-flight values) can be determined. The calibration measurements can be performed during a time slot reserved for calibration. This time slot can also be located within a measurement period for acquiring a set of detection points. The calibration time slot can, for example, be inserted after X (e.g., X=8) chirps of an FMCW signal.

[0088] Calibration measurements can be performed within the frequency band used for detecting points (76-77 GHz) or in a separate frequency band (e.g., 77-81 GHz). The latter may be particularly relevant for CW signals. 24-2002

[0089] - 17 -

[0090] The accuracy of the position measurements is primarily dependent on the aperture of the radar sensors 201 and 202. For example, a 10° phase difference at 77 GHz in air can detect a distance difference of 0.1 mm.

[0091] The relative position and / or pose 203 of sensors 201 and 202 can be determined by triangulation of the propagation times and / or distances (generally the transmission path measurements 305) of the antenna channels 211 and 212. Additionally, a geometric model of sensors 201 and 202, including the positions of antennas 211 and 212, can be taken into account to enable a particularly precise determination of pose 203.

[0092] The position measurement can be performed, for example, by measuring the phase of a CW signal. The CW signal can be derived from a sensor-synchronized clock. Alternatively or additionally, a radar method (e.g., FMCW) can be used (e.g., by using the 4 GHz band). Alternatively or additionally, a 6G method can be used. Transmitting and receiving per channel (either simultaneously via coding or sequentially) can be done either directly (line of sight and / or known propagation path within the vehicle) or indirectly (via reflections from objects). In the case of an indirect path, the reflection point (determined by individual sensors) can be taken into account in the calculation so that the pose and / or position can be corrected for this additional path.

[0093] In one example, two short-range radar sensors 201 and 202, each with N=4 Tx 211 and M=4 Rx 212, can be installed in the front bumper of a vehicle 100, optionally at an angle of 45°, at the corners. The radar sensors 201 and 202 can be coherently synchronized via a central clock generator. The reflection of the transmitted signals at the bumper can be utilized (and is preferably not blocked by an absorber). This utilization occurs insofar as the signal is deliberately coupled into the front crossmember of the vehicle 100. The radar waves can be reflected and / or deflected by metallic and / or metallized structures. The crossmember can be hollow internally and can advantageously be used for a connection (i.e., as a transmission path 203) between the left and right sides of the vehicle 100. Coupling out on the other side can be analogous to coupling in (in particular, reciprocally).Thus, a direct (in-vehicle) path can be provided from one radar sensor 201 to the other radar sensor 202 (and vice versa).

[0094] In parallel to the conventional radar measurement (e.g., in the 76-77 GHz frequency band with a first oscillator), a second oscillator (e.g., in the 77-81 GHz frequency band) can be operated (possibly continuously) to perform time-of-flight and / or position measurements (generally to determine transmission path measurements 305). These can be performed sequentially from Txl to Tx4 by evaluating the phase using the FMCW radar principle. Based on the geometric distribution of the antennas 211, 212, the relative 3D pose 203 and the relative position of the radar sensors 201, 202 can be determined. The relative pose 203 can then be used to calculate the virtual aperture of the group of radar sensors 201, 202.

[0095] Fig. 4 shows a flowchart of a (possibly computer-implemented) method 400 for determining a set of detection points using a first and a second radar sensor 201, 202 of a (motor) vehicle 100. The first and the second radar sensor 201, 202 are mounted at different locations on the vehicle 100. The radar sensors 201, 202 each comprise N transmitting antennas 211 and M receiving antennas 212. The radar sensors 201, 202 can be operated synchronously to increase the effective aperture and / or the spatial resolution of the combined radar sensor resulting from the group of radar sensors 201, 202. The method 400 can be carried out by a control device 101 of the vehicle 100. 24-2002

[0096] - 19 -

[0097] Method 400 comprises determining, 401, in a calibration phase, based on calibration signals sent from the first radar sensor 201 to the second radar sensor 202, pose information with respect to the relative pose 203 between the first radar sensor 201 and the second radar sensor 202. During the operation of the vehicle 100, current pose information (in particular the current relative pose 203 between the first and the second radar sensor 201, 202) can be determined in a sequence of successive calibration phases.

[0098] The pose information can specify values ​​for one or more parameters of the relative pose 203 between the first radar sensor 201 and the second radar sensor 203. Example parameters are:

[0099] • the distance between the first radar sensor 201 and the second radar sensor 202 (in up to three different spatial directions);

[0100] • a rotation between the first radar sensor 201 and the second radar sensor 202 (around up to three different axes of rotation).

[0101] The relative pose 203 between the first and second radar sensors 201, 202 can thus be defined by a total of six parameters. The pose information can specify values ​​for some or all of the parameters.

[0102] Method 400 further comprises the acquisition 402, using the first radar sensor 201, the second radar sensor 202 and the pose information, of a combined set of detection points in relation to the environment of the vehicle 100 for a measurement period. In this process, transmit signals can be emitted (e.g., in the 76-77 GHz frequency range) by the transmitting antennas 211 of the first and second radar sensors 201, 202 (in a coherent and / or synchronized manner). Furthermore, the receiving antennas 212 of the radar sensors 201, 202 can each receive (on the - 20 -

[0103] Received signals (based on transmitted signals) are acquired. These can be evaluated taking into account the pose information (e.g., using a Fast Fourier Transform) to determine the combined set of detection points.

[0104] The measurement period is preferably located so close in time to the calibration phase that the relative pose 203 between radar sensors 201 and 202 has not changed significantly since the calibration phase. Alternatively or additionally, the pose information determined during the calibration phase can be extrapolated to the measurement period (e.g., using a (Kalman) filter) to determine the relative pose 203 between radar sensors 201 and 202 for the measurement period (and to use it when determining the combined set of detection points).

[0105] The measures described in this document enable a particularly precise and flexible detection of detection points by a group of coherently operated radar sensors.

[0106] The present invention is not limited to the embodiments shown. In particular, it should be noted that the description and the figures are intended only to illustrate the principle of the proposed methods, devices, and systems by way of example.

Claims

24-2002 - 21 - Claims 1) Device (101) for determining a set of detection points using a first and a second radar sensor (201, 202) of a vehicle (100); wherein the device (101) is configured, - during a calibration phase, using calibration signals sent from the first radar sensor (201) to the second radar sensor (202), to determine pose information with respect to a relative pose (203) between the first radar sensor (201) and the second radar sensor (202); and - to acquire a combined set of detection points in relation to the vehicle's environment (100) for a measurement period using the first radar sensor (201), the second radar sensor (202) and the pose information. 2) Device (101) according to claim 1, wherein the device (101) is set up in the calibration phase, - To cause N transmitting units (211, 221) of the first radar sensor (201) to each send a calibration signal to the second radar sensor (202), with N>3; - to receive the N calibration signals via M receiver units (212, 222) of the second radar sensor (202), with M>3; and - to determine the pose information based on the N calibration signals received via the M receiving units (212, 222). 3) Device (101) according to claim 2, wherein the device (101) is set up in the calibration phase, - to determine a plurality of transmission path measurements (305) based on the N calibration signals received via the M receiving units (212, 222); wherein a transmission path measurement (305) is in particular a propagation delay and / or a phase of a a receiving unit (212, 222) receives a calibration signal and / or specifies the length of a transmission path (215) between a transmitting unit (211, 221) and a receiving unit (212, 222); and - to determine the pose information based on the multitude of transmission path measurements (305). 4) Device (101) according to claim 3, wherein the plurality of transmission path measurements (305) comprises N x M transmission path measurements (305) for the corresponding N x M combinations of each transmitting unit (211, 221) of the first radar sensor (201) and each receiving unit (212, 222) of the second radar sensor (202). 5) Device (101) according to one of claims 3 to 4, wherein - the device (101) is set up to determine the pose information based on the multitude of transmission path measurements (305) using a previously determined vehicle model and / or by means of a triangulation method; and - the vehicle model - includes a model trained through machine learning; and / or - includes an assignment function that assigns different relative positions (203) to different combinations of values ​​for the multitude of transmission path measured values ​​(305). 6) Device (101) according to any one of claims 2 to 5, wherein the device (101) is configured to send the N calibration signals via one or more, in particular metallic, components of the vehicle (100). 24-2002 - 23 - 7) Device (101) according to any one of claims 2 to 6, wherein the device (101) is configured to cause the N transmitting units (211, 221), - to send the N calibration signals in the same frequency band that is also used for determining the number of detection points; and - to send the N calibration signals in a time slot that is not used for capturing the number of detection points. 8) Device (101) according to any one of claims 2 to 6, wherein the device (101) is configured to cause the N transmitting units (211, 221) to transmit the N calibration signals in a frequency band that differs from the frequency band used for acquiring the quantity of detection points. 9) Device (101) according to any one of claims 2 to 8, wherein - the N transmitting units (211, 221) and the M receiving units (212, 222) each comprise antennas (211, 212) which are also used for recording the number of detection points; or - the N transmitting units (211, 221) and the M receiving units (212, 222) each comprise at least one dedicated component, in particular a 6G transmitter or a 6G receiver, which is not used for recording the set of detection points. 10) Device (101) according to one of the preceding claims, wherein the device (101) is configured, - to determine pose information in a sequence of successive calibration phases with respect to the current relative pose (203) between the first radar sensor (201) and the second radar sensor (202) in the respective calibration phase; and 24-2002 - 24 - - to determine the pose information used to determine the combined set of detection points for the measurement period by interpolation and / or by filtering the pose information obtained for the sequence of successive calibration phases. 11) Device (101) according to one of the preceding claims, wherein the device (101) is configured, - to cause transmission signals to be emitted in a coherent and / or synchronized manner via the transmitting antennas (211) of the first radar sensor (201) and the second radar sensor (202) during the measurement period; and - to evaluate received signals received via receiving antennas (212) of the first radar sensor (201) and the second radar sensor (202), which are based on the transmitted signals, using the pose information to determine the combined set of detection points for the measurement period. 12) Device (101) according to one of the preceding claims, wherein the device (101) is configured for the respective measurement period of a sequence of successive measurement periods, - to determine pose information relating to the current pose (203) between the first radar sensor (201) and the second radar sensor (202) for the respective measurement period; and - using the first radar sensor (201), the second radar sensor (202) and using the pose information for the respective measurement period, to capture a combined set of detection points in relation to the vehicle's surroundings (100) for the respective measurement period. 24-2002 - 25 - 13) Device (101) according to one of the preceding claims, wherein the device (101) is configured, - to detect at least one object in the vicinity of the vehicle (100) based on the combined set of detection points; and / or - to guide the vehicle (100) automatically longitudinally and / or laterally based on the combined set of detection points. 14) Method (400) for determining a set of detection points using a first and a second radar sensor (201, 202) of a vehicle (100); wherein the method (400) comprises, - Determine (401), in a calibration phase, using calibration signals sent from the first radar sensor (201) to the second radar sensor (202), pose information with respect to a relative pose (203) between the first radar sensor (201) and the second radar sensor (202); and - Acquisition (402), using the first radar sensor (201), using the second radar sensor (202) and using the pose information, a combined set of detection points in relation to an environment of the vehicle (100) for a measurement period.

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