RECEIVING DEVICE OF A DETECTION DEVICE FOR MONITORING AT LEAST A MONITORING AREA FOR OBJECTS, DETECTION DEVICE, VEHICLE WITH AT LEAST A DETECTION DEVICE AND METHOD FOR OPERATING A DETECTION DEVICE

Description

Technical field

[0001] The invention relates to a receiving device of a detection device for monitoring at least one monitoring area for objects by means of electromagnetic scanning signals according to claim 1.

[0002] Furthermore, the invention relates to a detection device for monitoring at least one monitoring area for objects by means of electromagnetic scanning signals according to claim 11.

[0003] Furthermore, the invention relates to a vehicle with at least one detection device for monitoring at least one monitoring area for objects by means of electromagnetic scanning signals according to claim 12.

[0004] Furthermore, the invention relates to a method for operating a detection device for monitoring at least one monitoring area for objects according to claim 13. State of the art

[0005] A high-resolution LiDAR system is known from US patent 2019 / 0370614 A1. A laser source emits a carrier wave which is amplitude-, frequency-, or phase-modulated, or a combination thereof, in the modulator to generate a pulse with a bandwidth and duration. A splitter divides the chirp into a transmit beam with most of the beam's energy and a reference beam with a much lower energy, which is nevertheless sufficient to generate good heterodyne or homodyne interference with the backlight scattered from a target. For each scanned beam, multiple parts of the target scatter a corresponding reflected light signal back to the detector array, resulting in a point cloud based on the multiple distances of the respective multiple parts of the target illuminated by multiple beams and multiple backscatters.A chirp mixer compares a detected signal with the original chirp waveform output by the power divider and operational amplifier to generate an electrical signal with a beat frequency that depends on the frequency difference between the RF reference waveform and the detected waveform. Another operational amplifier and an FFT process are then used to determine the beat frequency.

[0006] Furthermore, US Patent 2020 / 0408912 A1 discloses a lidar system with a light source that emits a lidar signal with several different channels. This lidar system is designed to generate a multitude of composite signals, each assigned to a different channel and comprising a signal pair consisting of a reference signal of the emitted light and a comparison signal of the light reflected from an object. An electronic circuit is used to measure a frequency shift between the reference and comparison signals, inducing a frequency shift where the frequency shift of the signal pairs differs.

[0007] An electronic imaging system is known from US Patent 5,737,075 A. The system uses a spatial light modulator in the focal plane of a converging optical system. Each pixel of the modulator is controlled by a specific modulation function to uniquely encode the transmission at each pixel. A modulation detector sums the signal of all pixels. Following detection, the corresponding transformation of the summed signal yields specific pixel throughput-radiation intensity levels.

[0008] A lidar system is known from US patent 2020 / 0096613 A1 for transmitting and receiving light in the visible, near-infrared, and short-wave infrared spectrum. The lidar system comprises a supercontinuum laser and a receiving optic with a wavelength splitter to split the received echo signals into the visible, short-wave, and near-infrared ranges and distribute each to corresponding photosensors.

[0009] The invention is based on the objective of designing a receiving device, a detection device, a vehicle and a method of the type mentioned above, which can be implemented and / or operated with less effort. Disclosure of the invention

[0010] This problem is solved according to the invention in the receiving device by the fact that at least one frequency analysis means has at least one spectral analysis means with which electromagnetic signals can be analyzed to at least one electromagnetic spectrum, which can be output in at least one spectrum output range of the at least one spectral analysis means, and at least two signal conversion means with which separate electrical signals can be determined, are assigned to different sections of at least one spectrum output range of the at least one spectral analysis means, wherein the different sections of at least one spectrum output range of the at least one spectral analysis means correspond to different frequency ranges of at least one electromagnetic spectrum.

[0011] According to the invention, the at least one frequency analysis means comprises at least one spectral analysis means with which electromagnetic signals can be analyzed to at least one electromagnetic spectrum, in particular a frequency spectrum. In this way, the spectral analysis can be carried out directly at the electromagnetic level, in particular the optical level.

[0012] According to the invention, electromagnetic signals, in particular echo signals and / or sampling signals, can be transformed into a frequency spectrum optically. In contrast to an electrical Fourier transform, the optical transformation according to the invention can be implemented with lower losses. Furthermore, the number of electrical components required for the conversion to the frequency spectrum in the prior art LiDAR system can be reduced.

[0013] Advantageously, the at least one frequency analysis instrument can be used to analyze electromagnetic echo signals and / or electromagnetic sampling signals for at least one electromagnetic spectrum. In this way, the electromagnetic echo signals and the electromagnetic sampling signals can be processed together, and in particular correlated.

[0014] The electromagnetic spectrum is output in at least one spectrum output range of the at least one spectral analysis device. Different sections of the at least one spectrum output range correspond to different frequency ranges of the at least one electromagnetic spectrum. At least two signal conversion devices are assigned to different sections of the at least one spectrum output range. The corresponding different frequency ranges of the output spectrum can be separately acquired by the signal conversion devices and converted into corresponding electrical signals.

[0015] Advantageously, the at least one spectrum output range can extend frequency-wise over the possible frequencies of the electromagnetic sampling signals and the electromagnetic echo signals. In this way, the at least one spectrum output range completely covers the entire frequency range of the electromagnetic sampling signals and the echo signals.

[0016] Advantageously, the receiving device can have a plurality of signal conversion means, which are assigned to different sections along the at least one spectrum output range. In this way, the resolution in the acquisition of the at least one electromagnetic spectrum can be increased. Thus, the resolution in determining the distance to objects can be improved.

[0017] According to the invention, at least one electromagnetic sampling signal is a frequency-modulated continuous wave (FMCW) signal. The reflected echo signal is also an FMCW signal. A signal conversion device can generate an electrical signal at a defined time, which characterizes the signal strength of the corresponding section of the electromagnetic spectrum to which the signal conversion device is assigned. If a spectral line is present in the section of the electromagnetic spectrum at the defined time, a corresponding signal maximum is generated by the signal conversion device. A spectral line characterizes the presence of a frequency in the introduced electromagnetic signal. The frequency is characterized by the position of the spectral line in the at least one spectrum output region, in particular the section of the at least one spectrum output region in which the spectral line lies.

[0018] Advantageously, the receiving device can be implemented, at least partially, as a single-chip system. With single-chip systems, all or a large part of the system's functions can be integrated onto a single chip. Such single-chip systems can be implemented in a space-saving and robust manner. Single-chip systems are also known as "System-on-a-Chip".

[0019] With the receiving device according to the invention, maxima in a frequency spectrum of the electromagnetic signals, in particular the sampling signals and / or the echo signals, can be extracted using at least one frequency analysis.

[0020] Based on at least one frequency analysis, information about the at least one monitoring area, in particular object information about objects within the at least one monitoring area, can be determined. The information about the at least one monitoring area can be object information, in particular in the form of distances, velocities, and / or directions of objects from which the scanning signals are reflected, relative to at least one reference area, in particular the detection device.

[0021] Advantageously, at least one detection device can be designed as a Light Detection and Ranging (LiDAR) system, a Laser Detection and Ranging (LaDAR) system, or the like. Such detection devices can determine distances, velocities, and / or directions of objects relative to reference areas, particularly those of the detection device itself.

[0022] Advantageously, the invention can be used in vehicles, particularly motor vehicles. It can also be used in land vehicles, especially passenger cars, trucks, buses, motorcycles, or the like, aircraft, especially drones, and / or watercraft. The invention can also be used in vehicles that can be operated autonomously or at least semi-autonomously. However, the invention is not limited to vehicles. It can also be used in stationary applications, in robotics, and / or in machinery, especially construction or transport machinery such as cranes, excavators, or the like.

[0023] The detection device can advantageously be connected to, or be part of, at least one electronic control unit of a vehicle or machine, in particular a driver assistance system. In this way, at least some of the functions of the vehicle or machine can be operated autonomously or semi-autonomously.

[0024] The detection device can detect stationary or moving objects, in particular vehicles, persons, in particular gestures and / or movements, animals, plants, obstacles, road surface irregularities, in particular potholes or stones, road boundaries, traffic signs, open spaces, in particular parking spaces, precipitation or the like.

[0025] In an advantageous embodiment, at least one spectral analysis device can comprise at least one spectral apparatus. A spectral apparatus can be used to decompose electromagnetic signals into electromagnetic spectra.

[0026] Advantageously, at least one spectral analysis device can include at least one spectroscope. Spectroscopes can be implemented using simple means and / or in a space-saving manner.

[0027] Advantageously, at least one spectral analysis device can be designed as an on-chip spectroscope. In this way, at least one spectral analysis device can be implemented in a space-saving manner.

[0028] Advantageously, at least parts of at least one spectral analysis device can be integrated on an optical semiconductor chip, for example, an optical silicon chip (SoC). In other words, at least parts of the at least one spectral analysis device can be integrated on a so-called photonic integrated circuit (PIC). In this way, the at least one spectral analysis device can be implemented more compactly and robustly.

[0029] In a further advantageous embodiment, at least one signal conversion means can comprise at least one electro-optical component with which electromagnetic signals can be converted into electrical signals. In this way, the electromagnetic signals of the electromagnetic spectrum can be converted into electrical signals. The electrical signals can then be further processed with appropriate electrical components.

[0030] Advantageously, at least one signal conversion device can be implemented using sensors, in particular point sensors, line sensors and / or area sensors, especially (avalanche) photodiodes, photodiode arrays, CCD sensors, active pixel sensors, especially CMOS sensors, or the like. In this way, the signal conversion devices can be flexibly adapted to their intended use.

[0031] Advantageously, at least one signal conversion device can be designed for the frequencies of the electromagnetic signals, in particular the sampling signals and / or the echo signals. In this way, the efficiency of the signal conversion and / or the signal-to-noise ratio can be improved.

[0032] In a further advantageous embodiment, at least one frequency analysis means can include at least one recording control means with which a respective recording start time and / or a respective recording duration can be controlled for at least some of the signal conversion means. In this way, the electrical signals determined by the signal conversion means can be assigned a time parameter. Thus, a frequency-time profile of the electromagnetic signals to be analyzed, in particular the sampling signals and / or echo signals, can be determined.

[0033] In a further advantageous embodiment, the receiving device can have at least one storage means for storing at least a portion of the electrical signals acquired by the signal conversion means. In this way, the electrical signals can be stored. This allows the transmission of the electrical signals, particularly to subsequent digitizing means, to be slowed down. The number of digitizing means required for digitizing the electrical signals can thus be reduced. In particular, the at least one electrical storage means can reduce the number of analog-to-digital converter channels required for digitizing the electrical signals of the individual signal conversion means.

[0034] Advantageously, at least one storage device can have or consist of at least one analog memory cell. Analog electrical signals can be stored using analog memory cells.

[0035] Advantageously, the electrical storage devices can be filled and / or read simultaneously. In this way, the electrical signals derived from the electromagnetic spectrum can be stored and transmitted simultaneously. Thus, a snapshot of the electromagnetic spectrum can be processed using the electrical signals.

[0036] In a further advantageous embodiment, the receiving device can have at least one amplifying means for amplifying at least a portion of the electrical signals acquired by the signal conversion means. In this way, the power consumption of the electrical components of the receiving device can be reduced.

[0037] Advantageously, at least one amplification stage can include or consist of a low-bandwidth preamplifier, in particular a transimpedance amplifier (TIA). This further reduces the power consumption of the electrical components.

[0038] Advantageously, at least one amplifying device can optionally be arranged between a signal conversion device and a storage device. In this way, the electrical signals can be amplified before they are stored in the storage device.

[0039] Alternatively or additionally, at least one amplification device can be functionally arranged between a storage device and a digitizing device. In this way, the electrical signal stored in the storage device can be amplified by the digitizing device before digitization. Overall, this can improve the signal-to-noise ratio.

[0040] In a further advantageous embodiment, the receiving device can have at least one digitizing means for digitizing at least a portion of the electrical signals acquired by the signal conversion means. In this way, the analog electrical signals can be converted into digital signals. The digital signals can then be processed using appropriate digital electronic components.

[0041] Advantageously, at least one digitizing device can include at least one analog-to-digital converter. This makes digitization easier to implement.

[0042] Advantageously, at least one digitizing device can be functionally arranged behind at least one storage device. In this way, the storage device can be used to reduce the number of digitizing devices required, in particular the number of analog-to-digital converters.

[0043] In a further advantageous embodiment, at least one frequency analysis device can have at least one signal coupling area for coupling electromagnetic signals. In this way, reliable coupling of the electromagnetic signals into the frequency analysis device can be achieved.

[0044] Advantageously, at least one signal coupling area can be designed such that electromagnetic echo signals and electromagnetic sampling signals can be coupled into the at least one frequency analysis instrument in the same way. In this way, the electromagnetic echo signals and the electromagnetic sampling signals can be analyzed as a single electromagnetic spectrum. The frequency response of the echo signals and the frequency response of the sampling signals can thus be directly compared. Distance measurements can be more easily determined from this direct comparison of the frequency responses of the echo signals and the sampling signals.

[0045] In a further advantageous embodiment, the receiving device can have at least one means of determining received parameters for determining at least one received parameter for at least one detected object directly or indirectly from electrical signals that can be determined using signal conversion means. In this way, at least one distance parameter for a detected object can be determined via the electrical signals that characterize the frequency response of at least one electromagnetic echo signal.

[0046] Distance quantities are quantities that characterize the distance of an object to a defined reference point, in particular the detection device.

[0047] When determining distance using a direct time-of-flight method, the time of flight between sending and receiving the electromagnetic signals used to detect an object can serve as a distance parameter.

[0048] In distance determination using an indirect time-of-flight method, phase differences or frequency differences between a transmitted signal, in particular an electromagnetic signal or an electrical signal generating the electromagnetic signal, and the received reflected signal, in particular the reflected electromagnetic signal or an electrical signal generated from the reflected electromagnetic signal, can be used as distance parameters. Quantities characterizing phase differences or frequency differences, in particular spatial distances or distance parameters characterizing these spatial distances between spectral lines of a spectrum, in particular a frequency spectrum, of at least a part of the electromagnetic signals, can also be used as distance parameters.

[0049] Advantageously, at least one distance parameter can include at least one correlation parameter. With at least one correlation parameter, a correlation can be established between the electrical signals determined by the signal conversion methods, in particular the digitized electrical signals, and at least one distance parameter. In this way, the at least one distance parameter can be determined more easily from the electrical signals, in particular the digitized electrical signals.

[0050] Advantageously, at least one correlation mean can include at least one correlation table. In a correlation table, the correlations between the electrical signals, especially the digitized electrical signals, and the corresponding distance values ​​can be pre-stored, particularly at the end of the detection device's manufacturing process. The correlation can then be retrieved more quickly from a correlation table.

[0051] If both the electromagnetic echo signal and the electromagnetic sampling signal are coupled into the spectral analysis instrument, the respective spectral line can be generated for each electromagnetic signal at a defined point in time within the frequency spectrum. From the electromagnetic signals in the spectral lines, corresponding electrical signal maxima can be generated using the two appropriate signal conversion instruments, which correspond to the respective frequencies at the defined point in time. A difference frequency between the sampling signal and the echo signal can be directly determined from the correlation of these electrical signal maxima. Alternatively, with appropriate calibration, the distance of the detected object can also be directly determined from the correlation of the two signal conversion instruments involved.

[0052] Alternatively or additionally, at least one distance parameter can be calculated from the electrical signals determined using signal conversion methods or from the digitized electrical signals. This eliminates the need for correlation tables.

[0053] In a further advantageous embodiment, the receiving device can have at least one intensity determination means for determining an intensity quantity that characterizes the intensity of at least one electromagnetic signal introduced into the receiving device.

[0054] Advantageously, at least one intensity determination device can include an adding agent with which the individual intensities of the electrical signals, especially digitized electrical signals, determined using the individual signal conversion devices can be added. In this way, the intensity value can be easily determined.

[0055] Advantageously, at least one intensity determination device can be functionally arranged downstream of at least one digitization device. In this way, the digitized electrical signals can be added using appropriate digital addition devices.

[0056] Furthermore, the object of the invention is achieved in the detection device by the fact that at least one frequency analysis means has at least one spectral analysis means with which electromagnetic signals can be analyzed to at least one electromagnetic spectrum, which can be output in at least one spectrum output range of the at least one spectral analysis means. at least two signal conversion means, with which separate electrical signals can be determined, are assigned to different sections of at least one spectrum output range of the at least one spectral analysis means, wherein the different sections of at least one spectrum output range of the at least one spectral analysis means correspond to different frequency ranges of at least one electromagnetic spectrum.

[0057] Advantageously, the detection device can be implemented at least partially as a single-chip system.

[0058] Furthermore, the object of the invention is achieved in the vehicle by the fact that at least one frequency analysis means has at least one spectral analysis means with which electromagnetic signals can be analyzed to at least one electromagnetic spectrum, which can be output in at least one spectrum output range of the at least one spectral analysis means. at least two signal conversion means, with which separate electrical signals can be determined, are assigned to different sections of at least one spectrum output range of the at least one spectral analysis means, wherein the different sections of at least one spectrum output range of the at least one spectral analysis means correspond to different frequency ranges of at least one electromagnetic spectrum.

[0059] Advantageously, the vehicle can have at least one driver assistance system. With this at least one driver assistance system, vehicle functions, for example, driving functions or the like, can be operated autonomously or partially autonomously.

[0060] Advantageously, at least one detection device can be functionally connected to at least one driver assistance system. In this way, information about the monitored area, in particular object information such as distance, speed and / or direction of objects relative to the detection device or relative to the vehicle, can be transmitted to the driver assistance system and used to control the vehicle's functions.

[0061] Furthermore, the object of the invention is achieved in the method by analyzing electromagnetic signals in at least one spectrum using at least one spectral analysis medium. that at least one spectrum is output in at least one spectrum output range of the at least one spectral analysis device, different ranges of the at least one electromagnetic spectrum are converted to separate electrical signals with each associated signal conversion device.

[0062] According to the invention, electromagnetic signals, in particular sampling signals and / or echo signals, are analyzed into an electromagnetic spectrum. The electromagnetic spectrum is output in the spectrum output area of ​​the spectral analysis device. In the spectrum output area, the electromagnetic spectrum of a plurality of signal conversion devices, each assigned to a frequency range of the spectrum, is acquired and converted into corresponding electrical signals. The frequency responses of the electromagnetic signals, in particular the sampling signals and / or echo signals, are characterized using these electrical signals.

[0063] In an advantageous embodiment of the method, an electromagnetic sampling signal and the corresponding electromagnetic echo signal can be coupled into at least one spectral analysis device and analyzed in at least one electromagnetic spectrum. In this way, the electromagnetic sampling signal and the electromagnetic received signal can be more easily compared via the electrical signals generated by the signal conversion devices.

[0064] According to the invention, the electromagnetic scanning signal, and thus also the electromagnetic echo signal, is a frequency-modulated electromagnetic continuous wave signal, wherein a frequency difference between the scanning signal and the echo signal is determined from the position of the signal conversion means in whose region the corresponding spectral lines of the scanning signal and the echo signal lie at a defined time. The distance of a detected object can be determined from the frequency difference.

[0065] Furthermore, the features and advantages described in connection with the receiving device, the detection device, the vehicle, and the method according to the invention, and their respective advantageous embodiments, apply to each other accordingly and vice versa. The individual features and advantages can, of course, be combined with one another, potentially resulting in further advantageous effects that go beyond the sum of the individual effects. Brief description of the drawings

[0066] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are explained in more detail with reference to the drawing. The person skilled in the art will expediently consider the features disclosed in the drawing, the description, and the claims individually and combine them into meaningful further combinations. The drawing schematically illustrates Figure 1 shows a vehicle in front view with a driver assistance system and a LiDAR system for monitoring a monitoring area 13 in the direction of travel in front of the vehicle; Figure 2 shows a functional diagram of the LiDAR system from the Figure 1 Figure 3 shows a frequency-time diagram of an electromagnetic sampling signal, exemplified by a frequency-modulated continuous wave signal from the LiDAR system. Figures 1 and 2for monitoring the monitoring area and a corresponding electromagnetic echo signal of the reflected sampling signal; Figure 4 shows a section of the frequency-time diagram from the Figure 3 , with a sampling sequence of the electromagnetic sampling signal and a corresponding echo sequence of the electromagnetic echo signal, wherein respective frequency ranges of the frequency spectrum of the electromagnetic signals are marked on the frequency axis, each of which is derived from a spectrum section of a spectrum output range of a spectroscope of the LiDAR system. Figure 2 Figure 5 shows a frequency spectrum of the electromagnetic sampling signal and the electromagnetic echo signal from the Figure 4 in the spectrum output range of the spectroscope at a time T.

[0067] In the figures, identical components are labelled with the same reference symbols. embodiment(s) of the invention

[0068] In the Figure 1Vehicle 10 is shown as an example in the form of a passenger car in front view.

[0069] Vehicle 10 is equipped with a detection device, for example, a LiDAR system 12. The LiDAR system 12 is, for example, located in the front bumper of vehicle 10. The LiDAR system 12 can monitor a surveillance area 13 in the direction of travel in front of vehicle 10 for objects 14. The LiDAR system 12 can also be located elsewhere on vehicle 10 and oriented differently. With the LiDAR system 12, object information, such as distances, directions, and velocities of objects 14, relative to at least one reference area of ​​vehicle 10 and / or the LiDAR system 12, for example, a longitudinal or transverse axis of vehicle 10, can be determined. The directions of objects can be specified, for example, as azimuth and / or elevation.

[0070] The objects in category 14 can be stationary or moving objects, such as other vehicles, people, animals, plants, obstacles, road surface irregularities (e.g., potholes or stones), road boundaries, traffic signs, open spaces (e.g., parking spaces), precipitation, or the like.

[0071] The LiDAR system 12 is designed as an example of a frequency-modulated continuous wave LiDAR system. Frequency-modulated continuous wave LiDAR systems are also known in technical circles as FMCW (frequency-modulated continuous wave) LiDAR systems. The LiDAR system 12 can determine the distances of objects 14 using a time-of-flight (TOF) method.

[0072] The LiDAR system 12 is connected to a driver assistance system 16. With the driver assistance system 16, the vehicle 10 can be operated autonomously or semi-autonomously.

[0073] The LiDAR System 12 is designed as an example of a so-called single-chip system, in which a large proportion of the components are implemented on a single chip. For example, some of the structures of the LiDAR System 12 can be integrated on an optical silicon chip (SoC). Alternatively, the LiDAR System 12 can also be implemented in other ways.

[0074] The LiDAR system 12 is in the Figure 2 shown in a functional diagram. The LiDAR system 12 comprises a transmitter 18, a receiver 20, a beam splitter 22, a beam deflector 24 and a lens 26.

[0075] The transmitting device 18 comprises signal generation means with which electrical transmission signals can be generated, for example, in the form of frequency-modulated continuous wave signals. An electrical transmission signal comprises a multitude of successive transmission sequences, for example, in the form of frequency ramps.

[0076] An electromagnetic signal source of the transmitting device 18 can be controlled with the electrical transmission signals so that it sends corresponding electromagnetic scanning signals 28, for example in the form of laser pulses, into the monitoring area 13. The transmitting device 18 can, for example, have one or more lasers as its electromagnetic signal source.

[0077] The electromagnetic sampling signals 28, like the generating electrical transmission signals, are frequency-modulated continuous-wave signals. An electromagnetic sampling signal 28 comprises a multitude of successive sampling sequences 30, exemplified as frequency ramps.

[0078] In the Figure 3In a frequency-time diagram, some sample sequences 30 of an electromagnetic sample signal 28 are shown as dashed lines, and for comparison, corresponding echo sequences 32 of an electromagnetic echo signal 34 are shown. The electromagnetic echo signal corresponds to the electromagnetic sample signal 28 reflected from an object 14.

[0079] Figure 4 shows a section of the frequency-time diagram with a sampling sequence 30 of the sampling signal 28 and the corresponding echo sequence 32 of the echo signal 34.

[0080] The beam splitter 22 is arranged in the beam path of the scanning signals 28 downstream of the transmitting device 18. The beam splitter 22 deflects a portion of the scanning signals 28 towards the receiving device 20. The deflected portion of the scanning signals 28 is in the Figure 2 For easier differentiation, it is designated with the reference symbol "28u".

[0081] The lens 26 is arranged in the beam path of the scanning signals 28 behind the beam splitter 22. The lens 26 shapes the undeflected part of the scanning signals 28, for example focusing and / or widening it, and directs it into the monitoring area 13.

[0082] The lens 26 can also direct echo signals 34 coming from the monitoring area 13 onto the beam deflector 24. The beam deflector 24 is located in the beam path of the echo signals 34 between the lens 26 and the receiving device 20.

[0083] The beam deflector 24 can be designed, for example, as a prism, mirror, or the like. The echo signals 34 can be deflected to the receiving device 20 by the beam deflector 24.

[0084] The receiving device 20 has a frequency analyzer 36. The frequency analyzer 36 can be used to analyze the echo signals 34 and the deflected sampling signals 28u with respect to their frequency. The frequency analyzer 36 comprises a spectral analyzer, for example in the form of a spectroscope 38, and a variety of signal conversion devices, for example in the form of photodiodes PD. The photodiodes PD can convert electromagnetic signals into electrical signals.

[0085] For the sake of clarity, the receiver 20 in the example described in the figures has only 9 photodiodes, PD 1 to PD 9. In practice, significantly more photodiodes, for example several hundred, are used to achieve a corresponding resolution when determining distances.

[0086] For easier identification, the reference symbols of the components assigned to the photodiodes PD 1 to PD 9 are also given indices between 1 and 9 below.

[0087] The spectroscope 38 has a signal input area 40 and a spectrum output area 42. In the signal input area 40, the echo signals 34 and the deflected sampling signals 28u are introduced in such a way that they are subjected to a frequency analysis. The spectroscope 38 separates the echo signals 34 and the deflected sampling signals 28u with respect to their wavelength, i.e., their frequency. The frequency spectrum 44 determined from the echo signals 34 and the deflected sampling signals 28u is output in the spectrum output area 42. Figure 5 The frequency spectrum 44 of a sampling signal 28u and an echo signal 34 at a time T is shown as an example.

[0088] The spatial extent of the spectrum output area 42 in the direction of the frequency resolution is adapted to the maximum bandwidth of frequencies of the sampling signals 28 and the echo signals 34. The spatial extent of the spectrum output area 42 is at least large enough to allow all possible frequencies of the sampling signals 28 and the echo signals 34 to be output.

[0089] Each of the photodiodes PD 1 to PD 9 is assigned to a corresponding spectrum section SA 1 to SA 9 of the spectrum output area 42. In the Figure 5 The nine spectrum sections SA 1 to SA 9 are shown as examples. The photodiodes PD 1 to PD 9 can convert the electromagnetic signals, for example in the form of spectral lines, from their respective assigned spectrum sections SA 1 to SA 9 into corresponding electrical signals.

[0090] Furthermore, the frequency analyzer 36 has a recording control device, for example in the form of a trigger device 46. With the trigger device 46, a recording start time and a recording duration for recording the frequency spectrum 44 with the photodiodes PD 1 to PD 9 can be defined. The outputs of the photodiodes PD 1 to PD 9 can be switched simultaneously with the trigger device 46. In this way, snapshots of the entire spectrum 44 can be taken.

[0091] Each photodiode PD 1 to PD 9 is assigned an electrical storage device, exemplified by an analog memory cell C 1 to C 9. The analog memory cells C 1 to C 9 are functionally located downstream of the trigger device 46 and are each connected to the output side of the corresponding photodiode PD 1 to PD 9. The electrical signals acquired by the photodiodes PD 1 to PD 9 can be temporarily stored in the analog memory cells C 1 to C 9. This allows subsequent signal transmission to be slowed down.

[0092] Functionally, a preamplifier V1 to V9 is arranged behind each analog memory cell C1 to C9. The respective electrical signals can be amplified using the preamplifiers V1 to V9, thus improving the signal-to-noise ratio.

[0093] Alternatively or additionally, suitable preamplifiers can also be functionally arranged upstream of the analog memory cells C1 to C9, for example between the photodiodes PD1 to PD9 and the analog memory cells C1 to C9. In this way, the electrical signals from the photodiodes PD1 to PD9 can be amplified before they reach the analog memory cells C1 to C9.

[0094] A digitizing unit 48 is functionally arranged downstream of the preamplifiers V1 to V9. The digitizing unit 48 digitizes the pre-amplified analog electrical signals from the photodiodes PD1 to PD9. For this purpose, the digitizing unit 48 can, for example, comprise a plurality of analog-to-digital converters.

[0095] A distance measurement device 50 is functionally arranged behind the digitization unit 48. The distance measurement device 50 can be used to determine a distance value from the digital electrical signals, which characterizes the distance of the object 14 detected by the LiDAR system 12 relative to the LiDAR system 12. The distance value is, for example, a measure of the frequency difference Δf between the echo signal 34 and the deflected sampling signal 28u.

[0096] The distance measurement tool 50 includes correlation averages in the form of a correlation table, which allows the corresponding distance of object 14 to be assigned to the distance measurement. The correlation table can be determined in advance, for example, during a calibration measurement, such as at the end of a production line, using the LiDAR system 12.

[0097] In the correlation table, for example, combinations of photodiodes PD, which in a snapshot capture a sampling spectral line SL A and a corresponding echo spectral line SL E of the spectrum 44 described below at defined distances of an object 14, can be correlated with the corresponding distances.

[0098] Furthermore, an optical intensity determination device 52 is functionally arranged downstream of the digitizing device 48. With the optical identification device 52, the intensity of the echo signals 34 and the intensity of the deflected sampling signals 28u can be determined from the digital electrical signals of the individual photodiodes PD 1 to PD 9. For this purpose, the corresponding digitized individual signals of the photodiodes PD 1 to PD 9 can be reassembled to form the respective overall signal.

[0099] The analog storage cells C 1 to C 9, the preamplifiers V 1 to V 9, the digitizing device 48, the distance measurement device 50 and the optical identification device 52 are, by way of example, part of the receiving device 20.

[0100] The information obtained by the receiving device 20, namely the distance, the intensity of the echo signals 34 and the intensity of the deflected scanning signals 28u, can be transmitted to the driver assistance system 16 via a corresponding connection.

[0101] To operate the LiDAR system 12, an electromagnetic scanning signal 28 is sent to the beam splitter 22 by the transmitter 18.

[0102] With the beam splitter 22, a part of the electromagnetic scanning signal 28 is separated and sent to the signal coupling area 40 of the spectroscope 38.

[0103] The unfiltered portion of the scanning signal 28 passes through the lens 26 into the monitoring area 13. The scanning signal 28 is reflected by an object 14. The reflected echo signal 34 passes through the lens 26 to the beam deflector 24.

[0104] The beam deflector 24 directs the echo signal 34 into the signal coupling area 40 of the spectroscope 38.

[0105] In the Figure 4 In a frequency-time diagram, an example of a sampling sequence 30 of the deflected sampling signal 28u and an echo sequence 32 of the echo signal 34, as they are fed to the signal coupling area 40, are shown.

[0106] Due to the flight time between the transmission of the sampling sequence 30 with the transmitting device 18 and the reception of the echo sequence 32 with the receiving device 20, as described in the Figure 4As shown, the echo sequence 32 is shifted relative to the sampling sequence 30 by the time interval Δt. Since these are frequency-modulated continuous wave signals, the frequency of the echo sequence 32 is also shifted relative to the frequency of the sampling sequence 30 by the frequency difference Δf at any given time.

[0107] The spectroscope 38 analyzes the deflected sampling signal 28u and the echo signal 34 with respect to their frequency. The corresponding frequency spectrum 44 is output in the spectrum output area 42 of the spectroscope 38. The output frequency spectrum 44 is composed of the spectrum of the deflected sampling signal 28 and the spectrum of the echo signal 34. The spectrum 44 changes over time according to the frequency-modulated signal waveform of the sampling signal 28 and thus of the echo signal 34. Since both the deflected sampling signal 28u and the corresponding echo signal 34 are fed to the same signal coupling area 40 of the receiving device 20 and analyzed with respect to frequency in the same way, the frequency spectra of the sampling signal 28u and the echo signal 34 can be directly compared in the single frequency spectrum 44.

[0108] In the Figure 5An example snapshot of the frequency spectrum 44 at time T is shown. The frequency spectrum 44 exhibits, for example, a sampling spectral line SL A,T and an echo spectral line SL E,T. The sampling spectral line SL A,T originates from the sampling signal 28u. The position of the sampling spectral line SL A,T in the frequency spectrum 44 characterizes the frequency of the sampling signal 28u at time T. The sampling spectral line SL E,T originates from an echo signal 34. The position of the sampling spectral line SL A,T in the frequency spectrum 44 characterizes the frequency of the echo signal 34 at time T.

[0109] A spatial line spacing 54 between the sampling spectral line SL A,T and the echo spectral line SL E,T on the spectrum appearance side 42 is a measure of the frequency difference Δf between the deflected sampling signal 28u and the echo signal 34. The frequency difference Δf, and thus the line spacing 54, correlates with the distance of the object 14 from the LiDAR system 12.

[0110] Photodiodes PD 1 to PD 9 detect the signal components of spectrum 44 in the corresponding spectrum sections SA 1 to SA 9 and convert them into electrical signals. These electrical signals are present at the outputs of photodiodes PD 1 to PD 9.

[0111] By appropriate control with the trigger device 46, the electrical signals at the outputs of the photodiodes PD 1 to PD 9 are simultaneously read out and transmitted to the corresponding analog memory cells C 1 to C 9. In the analog memory cells C 1 to C 9, the snapshot of the spectrum 44, for example at time T, is present in the form of electrical signals. In the Figure 5 The snapshot shown shows the echo spectral line SL E,T being captured with photodiode PD 4 and the sampling spectral line SL A,T being captured with photodiode PD 7.

[0112] The electrical signals from the analog memory cells C 1 to C 9 are fed to the respective preamplifiers V 1 to V 9 and amplified by them.

[0113] The amplified electrical signals are then digitized using the digitizing device 48.

[0114] The digitally amplified electrical signals are fed to the distance measurement device 50. Since the positions of the photodiodes PD 1 to PD 9 are defined and assigned to the spectral sections SA 1 to SA 9, the distance is determined from the combination of the photodiodes PD, in this example photodiode PD 4 and photodiode PD 7, which detect the sampling spectral line SL A,T and the echo spectral line SL E,T.

[0115] Furthermore, the amplified digital electrical signals from all photodiode branches are fed to the optical intensity determination device 52. The digital electrical signals are combined using the optical intensity determination device 52. From this combination, the intensities of the sampling signals 28u and the echo signals 34 are determined.

[0116] The distances and intensities are transmitted to the driver assistance system 16. With the driver assistance system 16, the vehicle 10 is operated at least semi-autonomously.

Claims

1. Receiving device (20) of a detection apparatus (12) for monitoring at least one monitoring region (13) for objects (14) by means of electromagnetic scanning signals (28), comprising a signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9) for converting electromagnetic signals (28u, 34), which originate from electromagnetic scanning signals (28), into electrical signals, and comprising at least one frequency analysing means (36) for analysing the frequency of signals, wherein at least one frequency analysing means (36) includes at least one spectral analysing means (38), using which electromagnetic signals (28u, 34) can be analysed to form at least one electromagnetic spectrum (44), which can be output in at least one spectrum output region (42) of the at least one spectral analysing means (38), wherein at least two signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9), using which separate electrical signals can be determined, are assigned to different sections (SA1, SA2, SA3, SA4, SA5, SA6, SA7, SA8, SA9) of at least one spectrum output region (42) of the at least one spectral analysing means (38), wherein the different sections (SA1, SA2, SA3, SA4, SA5, SA6, SA7, SA8, SA9) of at least one spectrum output region (42) of the at least one spectral analysing means (38) correspond to different frequency ranges of at least one electromagnetic spectrum (44), wherein the electromagnetic scanning signal (28), and thus also the electromagnetic echo signal (34), is a frequency-modulated electromagnetic continuous signal, and characterized in that a frequency difference between the scanning signal (28) and the echo signal (34) is determined from the position of the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9), in the range of which at a defined point in time corresponding spectral lines of the scanning signal (28) and of the echo signal (34) are located.

2. Receiving device according to Claim 1, characterized in that at least one spectral analysing means (38) includes at least one spectral apparatus.

3. Receiving device according to Claim 1 or 2, characterized in that at least one signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9) includes at least one electro-optical component, using which electromagnetic signals (28u, 34) can be converted into electrical signals.

4. Receiving device according to one of the preceding claims, characterized in that at least one frequency analysing means (36) includes at least one recording control means (46), using which a respective recording starting point in time (T) and / or a respective recording duration can be controlled for at least a part of the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9).

5. Receiving device according to one of the preceding claims, characterized in that the receiving device (20) includes at least one storage means (C1, C2, C3, C4, C5, C6, C7, C8, C9) for storing at least some of the electrical signals determined using the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9).

6. Receiving device according to one of the preceding claims, characterized in that the receiving device (20) includes at least one amplifying means (V1, V2, V3, V4, V5, V6, V7, V8, V9) for amplifying at least some of the electrical signals determined using the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9).

7. Receiving device according to one of the preceding claims, characterized in that the receiving device (20) includes at least one digitizing means (48) for digitizing at least some of the electrical signals determined using the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9).

8. Receiving device according to one of the preceding claims, characterized in that at least one frequency analysing means (36) includes at least one signal coupling region (40) for coupling in electromagnetic signals (28u, 34).

9. Receiving device according to one of the preceding claims, characterized in that the receiving device (20) includes at least one receiving variable determining means (50) for determining at least one receiving variable (54) for at least one detected object (14) directly or indirectly from electrical signals which can be determined using the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9).

10. Receiving device according to one of the preceding claims, characterized in that the receiving device (20) includes at least one intensity determining means (52) for determining an intensity variable, which characterizes an intensity of at least one electromagnetic signal (28u, 34) introduced into the receiving device (20).

11. Detection apparatus (12) for monitoring at least one monitoring region (13) for objects (14) by means of electromagnetic scanning signals (28), comprising at least one emitting device (18) for emitting electromagnetic scanning signals (28) into at least one monitoring region (13), comprising at least one receiving device (20) according to Claim 1.

12. Vehicle (10) having at least one detection apparatus (12) according to Claim 11.

13. Method for operating a detection apparatus (12) for monitoring at least one monitoring region (13) for objects (14), in which at least one electromagnetic scanning signal (28) is emitted into the at least one monitoring region (13) using at least one emitting device (18), electromagnetic echo signals (34) from electromagnetic scanning signals (28) reflected in the at least one monitoring region (13) are converted into electrical signals using at least one signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9) of a receiving device (20), signals (34) are subjected to a frequency analysis using at least one frequency analysing means (36) of the at least one receiving device (20), electromagnetic signals (34) are analysed in at least one spectrum (44) using at least one spectral analysing means (38), the at least one spectrum (44) is output in at least one spectrum output region (42) of the at least one spectral analysing means (38), different ranges of the at least one electromagnetic spectrum (44) are converted using respective assigned signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9) to form separate electrical signals, wherein the electronic scanning signal (28), and thus also the electromagnetic echo signal (34), is a frequency-modulated electromagnetic continuous signal, and characterized in that a frequency difference between the scanning signal (28) and the echo signal (34) is determined from the position of the signal converting means (PD1, PD2, PD3, PD4, PD5, PD6, PD7, PD8, PD9), in the range of which at a defined point in time corresponding spectral lines of the scanning signal (28) and of the echo signal (34) are located.

14. Method according to Claim 13, characterized in that an electromagnetic scanning signal (28u) and the corresponding electromagnetic echo signal (34) are coupled into at least one spectral analysing means (38) and analysed in at least one electromagnetic spectrum (44).