Lidar return signal processing method and apparatus

Abstract

The application provides a laser radar echo signal processing method and device. The method comprises: acquiring an echo signal; wherein the echo signal comprises a multi-dimensional signal emission angle; determining distance information of a detected object based on distance information of the echo signal; when the distance information of the detected object is less than or equal to a preset distance value, superimposing echo signals of each emission angle for a preset number of times, and outputting a superimposed target signal; and when the distance information of the detected object is greater than the preset distance value, performing non-phase accumulation on multi-angle echo signals based on a preset field window to obtain an accumulated target signal. Different echo signal processing methods are used for echo signals at different distances to improve the signal-to-noise ratio of signals at different distances, thereby improving the ranging capability of the radar.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent driving, and in particular to a laser radar echo signal processing method and device. BACKGROUND

[0002] The laser radar emits a detection signal to a to-be-detected object. When the detection signal passes through the to-be-detected object, the detection signal is reflected. The echo signal reflected by the to-be-detected object is received, and then the echo signal is processed. The signal-to-noise ratio is an important quality index in the signal processing process, which determines the ranging capability of the laser radar. Therefore, how to effectively improve the signal-to-noise ratio of the laser radar echo signal has become a problem to be solved. SUMMARY

[0003] The embodiments of the present application provide a laser radar echo signal processing method and device, which can effectively improve the signal-to-noise ratio of the laser radar echo signal, thereby improving the ranging capability of the laser radar echo signal.

[0004] To solve the above technical problems, the present application includes the following technical solutions:

[0005] In a first aspect, the embodiments of the present application provide a laser radar echo signal processing method, which comprises:

[0006] acquiring an echo signal; wherein the echo signal comprises a multi-dimensional signal emission angle;

[0007] judging distance information of a detection object based on distance information of the echo signal;

[0008] when the distance information of the detection object is less than or equal to a preset distance value, superimposing echo signals of each emission angle in a preset number of times, and outputting a target signal after superposition;

[0009] when the distance information of the detection object is greater than the preset distance value, performing non-coherent accumulation on multi-angle echo signals based on a preset field window, and obtaining the target signal after accumulation.

[0010] In a second aspect, the embodiments of the present application provide a laser radar echo signal processing device, which comprises:

[0011] an acquisition module configured to acquire an echo signal; wherein the echo signal comprises a multi-dimensional signal emission angle;

[0012] a judgment module configured to judge distance information of a detection object based on distance information of the echo signal;

[0013] a superposition module configured to, when the distance information of the detection object is less than or equal to a preset range, superimpose echo signals of each emission angle in a preset number of times, and output a target signal after superposition;

[0014] an accumulation module configured to, when the distance information of the detected object is greater than the preset range, perform non-coherent accumulation on the multi-angle echo signals based on a preset field window to obtain an accumulated target signal.

[0015] In a third aspect, an obstacle detection device is provided, which includes a processor, a memory, and a communication interface:

[0016] The processor is connected to the memory and the communication interface.

[0017] The memory is configured to store executable program codes.

[0018] The processor runs a program corresponding to the executable program codes by reading the executable program codes stored in the memory, so as to execute the laser radar echo signal processing method provided in any one of the first aspect.

[0019] In a fourth aspect, a computer readable storage medium is provided, which stores a computer program, and the program is executed by a processor to implement the laser radar echo signal processing method provided in any one of the first aspect.

[0020] The present application provides a laser radar echo signal processing method, which includes obtaining an echo signal; wherein the echo signal includes a multi-dimensional signal emission angle; determining the distance information of a detected object based on the distance information of the echo signal; when the distance information of the detected object is less than or equal to a preset distance value, superimposing each emission angle echo signal of a preset number, and outputting a superimposed target signal; when the distance information of the detected object is greater than the preset distance value, performing non-coherent accumulation on the multi-angle echo signals based on a preset field window to obtain an accumulated target signal. By using different echo signal processing methods for echo signals of different distances, the signal-to-noise ratio of signals of different distances is improved, thereby improving the ranging capability of the radar. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor based on these drawings.

[0022] Figure 1 is an application scenario diagram of the laser radar echo signal processing method provided by the embodiments of the present application;

[0023] Figure 2is a flowchart of a laser radar echo signal processing method provided by an embodiment of the present application;

[0024] Figure 2a is a schematic diagram of performing echo signal superposition for each angle provided by an embodiment of the present application;

[0025] Figures 2b-2d is a schematic diagram of performing preset field window setting provided by an embodiment of the present application;

[0026] Figure 2e is a schematic diagram of preset field window adjustment provided by an embodiment of the present application;

[0027] Figure 3 is a flowchart of a laser radar echo signal processing method provided by an embodiment of the present application;

[0028] Figure 3a is a schematic diagram of a central detection field of view and an edge detection field of view in a laser radar detection field of view provided by an embodiment of the present application;

[0029] Figure 4 is a block diagram of a laser radar echo signal processing device provided by an embodiment of the present application;

[0030] Figure 5 is a block diagram of another laser radar echo signal processing device provided by an embodiment of the present application;

[0031] Figure 6 is a block diagram of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the above objectives, features and advantages of the present application more apparent and understandable, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0033] The terms "first", "second", "third", and the like in the specification and claims of the present application and the above drawings are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed or can optionally include other steps or units inherent to the process, method, product or device.

[0034] Please refer to Figure 1 , Figure 1 is a laser radar echo signal processing method provided by an embodiment of the present application, which can be applied to, for example Figure 1The application environment shown. The laser radar 102 detects the return signal by emitting a probe signal, which is reflected after encountering the object to be detected. The laser radar can be a solid-state laser radar. The laser radar 102 receives the return signal reflected by the object to be detected through the receiver, which can be a silicon photomultiplier (SiPM). The laser radar 102 sends the return signal to the computer device 104, and the return signal includes multi-dimensional signal emission angles. The computer device 104 buffers the return signal according to the multi-dimensional signal emission angles to obtain a buffered signal. The computer device 104 selects a processing strategy for the return signal according to the information of the return signal, thereby obtaining a target signal.

[0035] It can be understood that the computer device 104 can be integrated in the laser radar 102 in whole or in part, or can exist independently of the laser radar 102.

[0036] The laser radar 102 can include a micro-electro-mechanical system (MEMS) solid-state laser radar, a flash laser radar. The specific type of laser radar is not limited in the embodiments of the present application, and the installation position and number of the laser radar are not limited.

[0037] In one embodiment, please refer to Figure 2 , Figure 2 is a flowchart of a laser radar return signal processing method in an embodiment of the present application, the method comprising:

[0038] S201, obtaining a return signal; wherein the return signal includes multi-dimensional signal emission angles.

[0039] The return signal can be obtained according to the scanning mode of the laser radar.

[0040] Specifically, different types of laser radars have different scanning modes for point cloud data. The MEMS laser radar is scanned by the simple harmonic vibration of the galvanometer, so that the optical path scanning path is realized, for example, a scanning field of view from top to bottom in the slow axis and left to right in the fast axis. For another example, the flash laser radar is scanned by the transmitter according to the preset control logic in the fast scanning mode. For another example, the mechanical laser radar is scanned by rotating the optical system 360 degrees by the mechanical driving device to realize scanning, and a cylindrical detection area with the laser radar as the center.

[0041] The laser radar transmits a detection laser. After encountering an object to be detected, the detection laser reflects a return signal. The laser radar receives the return signal through a receiver. A computer device receives the return signal transmitted by the laser radar. The return signal can include a preamble signal, an effective return signal, a false return signal, and environmental noise. The return signal includes a multi-dimensional signal emission angle. The multi-dimensional signal emission angle can include a pitch and a yaw. One pitch can correspond to multiple yaws, and one yaw can correspond to multiple pitches. Different signal emission angles can correspond to independent signal emission and reception, i.e., different detection signals and return signals. The number of signal emission angles can be determined according to the single field resolution of the laser radar. For example, the single field resolution of a solid-state laser radar is 76*250, and the solid-state laser radar can include 76 pitches and 250 yaws. The return signal of the multi-dimensional signal emission angle can be obtained by adjusting the deflection angle of a scanning device of the laser radar. It can be understood that the multi-dimensional signal emission angle can also be achieved by adjusting different emitters to perform fast-scan emission of the detection laser.

[0042] In the formula, it can be understood that the computer device can buffer the return signal according to the multi-dimensional signal emission angle after receiving the return signal. Specifically, the return signal received by the computer device can also include a signal reception sequence. A plurality of memories can be pre-configured in the computer device. The computer device determines a preset memory corresponding to the return signal according to the multi-dimensional signal emission angle and the signal reception sequence. Then, the computer device buffers the return signal in the determined preset memory.

[0043] In the formula, it can be understood that the return signal received by the computer device can include a signal reception sequence. The signal reception sequence can be a transmission sequence number corresponding to the return signal, or a transmission time corresponding to the return signal. A plurality of memories can be pre-configured in the computer device. The same number of return signals can be stored in the plurality of memories. Each memory has a corresponding storage capacity. The number of return signals stored in each memory can be less than or equal to the storage capacity. The multi-dimensional signal emission angle can include a pitch and a yaw. One pitch can correspond to multiple yaws, and one yaw can correspond to multiple pitches. The computer device can store a plurality of return signals with the same pitch and different yaws in a corresponding memory. The computer device adjusts the pitch of the laser radar, fixes the adjusted pitch, adjusts the yaw of the laser radar in the opposite direction of the last transmission of the detection signal, and obtains a return signal corresponding to the adjusted pitch. The computer device stores the return signal corresponding to the adjusted pitch in another memory.

[0044] The computer device caches the echo signal to obtain a cached signal. The computer device determines whether the number of the cached signal reaches a preset cache number. The preset cache number is related to the resolution of one detection field of view of the laser radar.

[0045] In one of the embodiments, before the echo signal is cached according to the signal emission angle of the multiple dimensions, the method further comprises: amplifying the received echo signal to obtain an amplified echo signal; performing analog-to-digital conversion on the amplified echo signal to obtain a converted digital signal; and performing filtering processing on the converted digital signal.

[0046] The computer device can amplify the weak echo signal through the amplification processing on the echo signal, so as to facilitate subsequent signal processing. The computer device performs analog-to-digital conversion on the amplified echo signal, so as to process the echo signal. The computer device performs filtering processing on the converted digital signal, and the filtering processing can be to remove the direct current component in the echo signal. The direct current component can be removed through a high-pass filter. The computer device can avoid the interference of the direct current component through the filtering processing on the converted digital signal.

[0047] S202, determining distance information of the detected object based on the echo signal.

[0048] It can be understood that the distance information of the detected object can be determined according to the distance information corresponding to the obtained echo signal.

[0049] It can be understood that the distance information of the detected object can also be determined according to the time region in which the echo signal is received. For example, the echo signal received within a first preset time range after the detection laser is emitted can output that the detected object is at a close distance. The echo signal received within a second preset time range after the detection laser is emitted can output that the detected object is at a far distance. It can be understood that the length of the second preset time range is greater than the length of the first preset time range.

[0050] S203, when the distance information of the detected object is less than or equal to a preset distance value, superimposing the echo signal of each emission angle for a preset number of times to output a superimposed target signal.

[0051] It can be understood that before the echo signal of each emission angle for a preset number of times is superimposed, the method further comprises: calling the echo signal of a preset number of times from a preset memory according to the emission angle. It can be understood that the preset number depends on the radar detection accuracy requirement. It can be understood that the higher the accuracy is, the more the preset number is.

[0052] Wherein, the echo signals of each angle are superimposed to output a superimposed target signal, as shown in Figure 2a .

[0053] S204 When the probe object distance information is greater than the preset distance value, the multi-angle echo signals are non-phase accumulation based on the preset field window to obtain the accumulated target signals.

[0054] Wherein, it can be understood that, before the non-phase accumulation of the multi-angle echo based on the preset field window, the method further comprises: obtaining the receiving order of the multi-angle echo signals; and setting the preset field window based on the receiving order of the multi-angle echo signals.

[0055] Wherein, it can be understood that, in consideration of the minimum time delay of the measurement point cloud output, for the design of scanning in time sequence in horizontal direction, the preset field window is preferably set in horizontal direction for accumulation; for the design of scanning in time sequence in vertical direction, the preset field window is preferably set in vertical direction for accumulation; for the design of scanning in time sequence in matrix block, i.e. the design of transmitting in matrix block as the minimum unit, the preset field window is preferably set in matrix block for accumulation. Without considering the time delay of the measurement point cloud output, the matrix block accumulation can achieve the optimal ranging performance. Specifically, as shown in Figure 2b , Figure 2c , Figure 2d Three design diagrams of the preset field window with different arrangements are given.

[0056] Wherein, it can be understood that, the acquisition of the original waveform of the echo signal of any one angle in the multi-angle echo signal can be the result of one measurement; as a preferred embodiment, in order to obtain better ranging performance, the echo signal of any one angle can also be the superimposed echo signal obtained by accumulating multiple measurement results, as shown in Figure 2a .

[0057] Wherein, as an optional embodiment, before the non-phase accumulation of the multi-angle echo signals based on the preset field window, the method further comprises: obtaining the similarity of the adjacent angle echo data in the preset field window; when the similarity is greater than a preset threshold, the non-phase accumulation is performed based on the preset field window to obtain the accumulated target signals; when the similarity is less than or equal to the preset threshold, the preset field window is adjusted based on the similarity value.

[0058] Wherein, it can be understood that the similarity calculation can use the difference of echo area of adjacent data as a judgment condition; it can also make the difference of echo starting time of adjacent data as a judgment condition; it can also use both the difference of echo area and the difference of echo starting time as a judgment condition. According to different distance scenes, set different condition thresholds Th_Area of the difference of echo area, and set different condition thresholds Th_start of the difference of echo starting time. Wherein, it can be understood that the farther the distance, the greater the condition threshold Th_Area of the difference of echo area set, and the farther the distance, the greater the condition threshold Th_start of the difference of echo starting time set. When using both the difference of echo area and the difference of echo starting time as a judgment condition, when the difference of echo area of adjacent data is less than or equal to Th_Area, and when the difference of echo starting time of adjacent data is less than or equal to Th_start, it means that the adjacent data is similar, otherwise it means that it is not similar.

[0059] Wherein, as an optional embodiment, when the similarity is less than or equal to a preset threshold, adjusting the preset field window based on the similarity value, including: when judging that the total similarity value of the corresponding echo signals in the preset field window is less than the preset threshold, calculating the similarity of any two adjacent echo signals in the preset field window respectively, judging the echo signals in the preset field window whose similarity values are different from other echo signals; according to the angle information of the echo signals in the preset field window whose similarity values are different from other echo signals, adjusting the preset field window, so that the similarity values of the echo signals included in the preset field window are greater than the preset threshold.

[0060] For example, as described in Figure 2e , 2e is the specific adjustment process of the preset field window, as Figure 2e (a) shown, the initial preset field window includes A1, A2, A3, B1, B2, B3, C1, C2, C3 and other echo signals, judging the similarity of A1, A2, A3, B1, B2, B3, C1, C2, C3 and other echo signals in the initial preset field window, if the similarity of A3, B3, C3 does not meet the preset requirement, adjust the preset field window to as Figure 2e (b) shown.

[0061] In the embodiment, an echo signal is acquired, wherein the echo signal comprises a multi-dimensional signal transmission angle; distance information of a detected object is determined based on the echo signal; when the distance information of the detected object is less than or equal to a preset distance value, echo signals of each transmission angle for a preset number of times are superimposed, and a superimposed target signal is output; when the distance information of the detected object is greater than the preset distance value, multi-angle echo signals are non-coherent accumulated based on a preset field window, and an accumulated target signal is obtained. By using different echo signal processing methods for echo signals of different distances, the signal-to-noise ratio of the signals of different distances is improved, thereby improving the ranging capability of the radar. It can be understood that for signals of a short distance, the signal-to-noise ratio of each angle echo signal can be improved by superimposing multiple transmission echo signals of each angle, and the detection capability is improved. For echo signals of a long distance, not only the signal-to-noise ratio of each angle echo signal can be improved by superimposing each angle echo signal, but also non-coherent accumulation of the echo signals can be performed on this basis, the spatial correlation between the echo signals of the multi-dimensional signal transmission angle is utilized, the accumulation number of the signals is improved in the case of phase loss of the target signal, the signal-to-noise ratio of the echo signals is improved, and the ranging capability of the echo signals is effectively improved. At the same time, in the embodiment, the similarity of the echo signals in the preset field window is determined, the accuracy of the signals after non-coherent accumulation is ensured, and the ranging capability is further improved.

[0062] In another embodiment, refer to Figure 3 Figure 3 is a flowchart of a laser radar echo signal processing method in the embodiment of the application, the method comprises:

[0063] S301, an echo signal is acquired, wherein the echo signal comprises a multi-dimensional signal transmission angle;

[0064] ​The laser radar transmits a detection signal. After encountering an object to be detected, the detection signal reflects a return signal. The laser radar receives the return signal through a receiver. A computer device receives the return signal transmitted by the laser radar. The return signal can include a preamble signal, an effective return signal, a false return signal, and environmental noise. The return signal includes a multi-dimensional signal transmission angle. The multi-dimensional signal transmission angle can include a pitch angle and a yaw angle. The same pitch angle can correspond to multiple yaw angles, and the same yaw angle can correspond to multiple pitch angles. Different signal transmission angles can correspond to independent signal transmission and reception, i.e., different detection signals and return signals. The number of signal transmission angles can be determined according to the single field resolution of the laser radar. For example, the single field resolution of a solid-state laser radar is 76*250, and the solid-state laser radar can include 76 pitch angles and 250 yaw angles. The return signal of the multi-dimensional signal transmission angle can be obtained by adjusting the deflection angle of the scanning device of the laser radar. It can be understood that the multi-dimensional signal transmission angle can also be achieved by adjusting different emitters to perform fast-scan transmission detection laser.

[0065] In the method, it can be understood that the computer device can cache the return signal according to the multi-dimensional signal transmission angle after receiving the return signal. Specifically, the return signal received by the computer device can also include a signal receiving sequence. A plurality of memories are pre-configured in the computer device. The computer device determines a preset memory corresponding to the return signal according to the multi-dimensional signal transmission angle and the signal receiving sequence. Then, the computer device caches the return signal in the determined preset memory.

[0066] S302, determining distance information of the detection object based on distance information of the return signal;

[0067] It can be understood that, based on the return signal, the distance information of the detection object can be determined according to the distance information corresponding to the return signal obtained.

[0068] It can be understood that the distance information of the detection object can also be determined according to the time region in which the return signal is received, for example, the return signal received within a first preset time range after transmitting the detection laser can output that the detection object is at a close distance, and the return signal received within a second preset time range after transmitting the detection laser can output that the detection object is at a long distance. It can be understood that the duration of the second preset time range is greater than the duration of the first preset time range.

[0069] S303, when the distance information of the detection object is less than or equal to a preset distance value, superimposing return signals of each transmission angle for a preset number of times, and outputting a target signal after superposition;

[0070] Wherein, it can be understood that before superimposing the echo signals of each of the preset number of transmission angles, the method further comprises: retrieving the echo signals of the preset number from the preset memory according to the transmission angles.

[0071] Wherein, superimposing the echo signals of each angle outputs a superimposed target signal, as shown in Figure 2a .

[0072] S304, when the distance information of the detected object is greater than a preset distance value, obtaining the multi-angle echo signals corresponding to the central field of view;

[0073] Wherein, it can be understood that the definition of the central field of view and the edge field of view of the radar is related to the design parameters of the radar. As an example, we consider that the central field of view occupies 50% of the overall detection field of view, i.e. in the case of a horizontal detection field of view angle of 120 degrees, we consider that the middle 60 degrees is the central field of view in the horizontal direction; similarly in the vertical direction, i.e. in the case of a vertical detection field of view angle of 40 degrees, we consider that the middle 20 degrees is the central field of view in the vertical direction. As shown in Figure 3a , 3a is a schematic diagram of the central field of view and the edge field of view in a receiving field of view.

[0074] Wherein, it can be understood that obtaining the multi-angle echo signals corresponding to the central field of view specifically comprises: obtaining the horizontal field of view angle range and / or the vertical field of view angle range corresponding to the central field of view;

[0075] Retrieving the echo signals corresponding to the central field of view from the preset memory according to the horizontal field of view angle range and / or the vertical field of view angle range corresponding to the central field of view.

[0076] S305, non-coherent accumulation of the multi-angle echo signals corresponding to the central field of view based on a preset domain window, to obtain a target signal corresponding to the accumulated central field of view;

[0077] Wherein, as an optional embodiment, before non-coherent accumulation of the multi-angle echo signals corresponding to the central field of view based on a preset domain window, the method further comprises: obtaining the receiving order of the multi-angle echo signals; and setting the preset domain window according to the receiving order of the multi-angle echo signals.

[0078] Wherein, it can be understood that the acquisition of the original waveform of any one angle of the multi-angle echo signals can be the result of one measurement; as a preferred embodiment, in order to obtain better ranging performance, any one angle of the echo signals can also be a superimposed echo signal obtained by accumulating multiple measurement results, as shown in Figure 2a .

[0079] As an optional embodiment, before the non-coherent accumulation based on the preset field window is performed on the multi-angle echo signals corresponding to the central field of view, the method further comprises:

[0080] obtaining the similarity of adjacent angle echo data in the preset field window; when the similarity is greater than a preset threshold, performing non-coherent accumulation based on the preset field window to obtain the accumulated target signal; when the similarity is less than or equal to the preset threshold, adjusting the preset field window based on the similarity value.

[0081] It can be understood that the similarity calculation can use the difference between the echo areas of adjacent data as a judgment condition; it can also use the difference between the echo start times of adjacent data as a judgment condition; or both the difference between the echo areas and the difference between the echo start times can be used as a judgment condition. According to different distance scenarios, different condition thresholds Th_Area of the difference between the echo areas and different condition thresholds Th_start of the difference between the echo start times are set. It can be understood that the farther the distance, the greater the condition threshold Th_Area of the difference between the echo areas, and the farther the distance, the greater the condition threshold Th_start of the difference between the echo start times. When both the difference between the echo areas and the difference between the echo start times are used as a judgment condition, when the difference between the echo areas of adjacent data is less than or equal to Th_Area, and when the difference between the echo start times of adjacent data is less than or equal to Th_start, it indicates that the adjacent data are similar, otherwise it indicates that they are not similar.

[0082] As an optional embodiment, when the similarity is less than or equal to the preset threshold, adjusting the preset field window based on the similarity value comprises: when it is judged that the total similarity value of the echo signals corresponding to the preset field window is less than the preset threshold, calculating the similarity of any two adjacent echo signals in the preset field window respectively, judging the echo signals in the preset field window whose similarity values are different from those of other echo signals; adjusting the preset field window according to the angle information of the echo signals in the preset field window whose similarity values are different from those of other echo signals, so that the similarity values of the echo signals included in the preset field window are greater than the preset threshold.

[0083] S306, obtaining the multi-angle echo signals corresponding to the edge field of view; superimposing each transmission angle echo signal corresponding to the edge field of view to output the target signal corresponding to the superimposed edge field of view.

[0084] It can be understood that the acquisition of the multi-angle echo signal corresponding to the edge field of view specifically includes: acquiring the horizontal field of view angle range and / or the vertical field of view angle range corresponding to the edge field of view.

[0085] The echo signal corresponding to the edge field of view is retrieved from a preset memory according to the horizontal field of view angle range and / or the vertical field of view angle range corresponding to the edge field of view.

[0086] By adopting the embodiment, the echo signal is acquired, wherein the echo signal includes a multi-dimensional signal transmission angle; the distance information of a detected object is judged based on the echo signal; when the distance information of the detected object is less than or equal to a preset distance value, the echo signal of each transmission angle is superimposed for a preset number of times, and a superimposed target signal is output; when the distance information of the detected object is greater than the preset distance value, the multi-angle echo signal corresponding to the center field of view is acquired; the multi-angle echo signal corresponding to the center field of view is non-coherent accumulated based on a preset field window, and a target signal corresponding to the center field of view after accumulation is obtained; the multi-angle echo signal corresponding to the edge field of view is acquired; each transmission angle echo signal corresponding to the edge field of view is superimposed, and a target signal corresponding to the edge field of view after superposition is output. By adopting different echo signal processing methods for echo signals at different distances, the signal-to-noise ratio of the signals at different distances is improved, thereby improving the ranging capability of the radar. It can be understood that for signals at a close distance, the signal-to-noise ratio of each angle echo signal can be improved by superimposing multiple transmission echoes of each angle signal, and the detection capability is improved. For echo signals at a long distance, not only can the signal-to-noise ratio of each angle echo signal be improved by superimposing each angle echo signal, but also non-coherent accumulation of the echo signal can be performed on this basis, the spatial correlation between the echo signals of the multi-dimensional signal transmission angle is utilized, the accumulation number of the signals is improved in the case of phase loss of the target signal, the signal-to-noise ratio of the echo signal is improved, and the ranging capability of the echo signal is effectively improved. Further, the center field of view of the laser radar is mainly used for ranging, and the edge field of view is used for blind filling in the actual application scenario. In the case of improving the signal-to-noise ratio and the ranging capability by performing non-coherent accumulation on the center field of view and superimposing each angle echo signal on the edge field of view, the calculation amount is further reduced. Meanwhile, in the embodiment of the present application, the similarity of the echo signals in the preset field window is judged, the accuracy of the signal after non-coherent accumulation is ensured, and the ranging capability is further improved.

[0087] Please refer to Figure 4 as shown, Figure 4 is a laser radar echo signal processing device 400 provided by the embodiment of the present application, which comprises an acquisition module 401, a judgment module 402, a superposition module 403 and an accumulation module 404, wherein:

[0088] The acquisition module 401 is configured to acquire an echo signal, wherein the echo signal comprises a multi-dimensional signal transmission angle;

[0089] The judgment module 402 is configured to judge a distance of a detected object based on distance information of the echo signal.

[0090] The superposition module 403 is configured to, when the distance information of the detected object is less than or equal to a preset range, superpose echo signals of each transmission angle for a preset number of times, and output a superposed target signal.

[0091] The accumulation module 404 is configured to, when the distance information of the detected object is greater than the preset range, perform non-coherent accumulation on multi-angle echo signals based on a preset field window to obtain an accumulated target signal.

[0092] In one of the embodiments, the device can further comprise a storage module 405,

[0093] The storage module 405 is configured to determine a preset memory corresponding to the echo signal according to the multi-dimensional signal transmission angle and a signal receiving sequence of the echo signal, and cache the echo signal in the corresponding preset memory.

[0094] In one of the embodiments, the device can further comprise a setting module 406.

[0095] The acquisition module 401 is configured to acquire a receiving sequence of the multi-angle echo signal.

[0096] The setting module 406 is configured to set the preset field window based on the receiving sequence of the multi-angle echo signal.

[0097] In one of the embodiments, the device can further comprise an adjustment module 407.

[0098] The acquisition module 401 is further configured to acquire a similarity of adjacent angle echo data in the preset field window.

[0099] The accumulation module 404 is configured to, when the similarity is greater than a preset threshold, perform non-coherent accumulation based on the preset field window to obtain an accumulated target signal.

[0100] The adjustment module 407 is configured to, when the similarity is less than or equal to a preset threshold, adjust the preset field window based on the similarity value.

[0101] The specific limitations of the laser radar echo signal processing device 400 can refer to the limitations of the laser radar echo signal processing method S201-S204 described above, which will not be repeated here. Each module in the above laser radar echo signal processing device can be realized by software, hardware and their combination. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so that the processor calls and executes the operations corresponding to each module.

[0102] Please refer to Figure 5 as shown, Figure 5 The laser radar echo signal processing device 500 provided by the embodiment of the present application comprises an acquisition module 501, a judgment module 502, a superposition module 503 and an accumulation module 504, wherein:

[0103] The acquisition module 501 is configured to acquire an echo signal, wherein the echo signal comprises a multi-dimensional signal emission angle.

[0104] The judgment module 502 is configured to judge the distance of a detected object based on the distance information of the echo signal.

[0105] The superposition module 503 is configured to superpose the echo signals of each emission angle for a preset number of times when the distance information of the detected object is less than or equal to a preset range, and output a target signal after superposition.

[0106] The acquisition module 501 is further configured to acquire the multi-angle echo signals corresponding to the center field of view when the distance information of the detected object is greater than the preset range.

[0107] The accumulation module 504 is configured to perform non-coherent accumulation on the multi-angle echo signals corresponding to the center field of view based on a preset field window, and obtain a target signal after accumulation.

[0108] The acquisition module 501 is further configured to acquire the multi-angle echo signals corresponding to the edge field of view.

[0109] The superposition module 503 is further configured to superpose the echo signals of each emission angle corresponding to the edge field of view, and output a target signal after superposition corresponding to the edge field of view.

[0110] In one of the optional embodiments, the device comprises a storage module 505,

[0111] The storage module 505 is configured to determine a preset memory corresponding to the echo signal according to the multi-dimensional signal emission angle and the signal receiving sequence of the echo signal, and cache the echo signal in the corresponding preset memory.

[0112] In an optional embodiment, the apparatus further comprises a setting module 506,

[0113] The acquisition module 501 is configured to acquire a receiving sequence of the multi-angle echo signals.

[0114] The setting module 506 is configured to set the preset field window based on the receiving sequence of the multi-angle echo signals.

[0115] In an optional embodiment, the apparatus further comprises an adjusting module 507,

[0116] The acquisition module 501 is further configured to acquire a similarity of adjacent-angle echo data in the preset field window.

[0117] The accumulation module 504 is configured to, when the similarity is greater than a preset threshold, perform non-coherent accumulation based on the preset field window to obtain an accumulated target signal.

[0118] The adjusting module 507 is configured to, when the similarity is less than or equal to the preset threshold, adjust the preset field window based on the similarity value.

[0119] For specific limitations of the laser radar echo signal processing apparatus 500, refer to the limitations of the laser radar echo signal processing method S301-S306 in the foregoing, which will not be repeated here. Each module in the above laser radar echo signal processing apparatus can be realized by software, hardware, and combinations thereof, in whole or in part. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to call and execute the operations corresponding to each module by the processor.

[0120] In another embodiment, a computer device is provided, and an internal structure diagram thereof can be as shown in Figure 6 The computer device comprises a processor, a memory, a communication interface, and a database connected through a system bus. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, computer readable instructions, and a database. The internal memory provides an environment for the operating system and computer readable instructions in the non-volatile storage medium. The database of the computer device is configured to store echo signals and target signals. The communication interface of the computer device is configured to connect and communicate with a laser radar. The computer readable instructions are executed by the processor to implement the above laser radar echo signal processing method S201-S204 or S301-S306, which will not be repeated here.

[0121] Those skilled in the art can understand that,Figure 6 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0122] One or more non-volatile computer-readable storage media storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of any of the various method embodiments described above.

[0123] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by computer-readable instructions instructing related hardware. The computer-readable instructions can be stored in a non-volatile computer-readable storage medium and, when executed, can include the processes of the above-mentioned method embodiments. Any reference to memory, storage, databases, or other media in each embodiment provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0124] Each technical feature of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist, they should be considered as within the scope of the present application.

[0125] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that, for a person of ordinary skill in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A method for processing a laser radar echo signal, the method comprising: acquiring an echo signal, wherein the echo signal comprises a plurality of signal transmission angles; judging distance information of a detected object based on the echo signal; when the distance information of the detected object is less than or equal to a preset distance value, superimposing echo signals of each transmission angle for a preset number of times, and outputting a superimposed target signal; when the distance information of the detected object is greater than the preset distance value, acquiring a receiving sequence of the echo signals of a plurality of angles, setting a preset field window based on the receiving sequence of the echo signals of the plurality of angles, and acquiring a similarity of adjacent angle echo data within the preset field window; when the similarity is greater than a preset threshold, non-coherent accumulation of the echo signals of the plurality of angles based on the preset field window to obtain an accumulated target signal; and when the similarity is less than or equal to the preset threshold, adjusting the preset field window based on the similarity value.

2. The method of claim 1, wherein, After the echo signal is acquired, the method further comprises determining a preset memory corresponding to the echo signal according to the plurality of signal transmission angles and a signal receiving sequence of the echo signal; and storing the echo signal in the corresponding preset memory.

3. The method of claim 1, wherein, When the distance information of the detected object is greater than the preset distance value, the non-coherent accumulation of the echo signals of the plurality of angles based on the preset field window to obtain the accumulated target signal comprises: when the distance information of the detected object is greater than the preset distance value, acquiring the echo signals of the plurality of angles corresponding to a central field of view; non-coherent accumulation of the echo signals of the plurality of angles corresponding to the central field of view based on the preset field window to obtain an accumulated target signal corresponding to the central field of view; acquiring the echo signals of the plurality of angles corresponding to an edge field of view; superimposing echo signals of each transmission angle corresponding to the edge field of view, and outputting a superimposed target signal corresponding to the edge field of view. 4.A device for processing a laser radar echo signal, the device comprising: an acquisition module configured to acquire an echo signal, wherein the echo signal comprises a plurality of signal transmission angles; a judgment module configured to judge distance information of a detected object based on the echo signal; a superimposition module configured to, when the distance information of the detected object is less than or equal to a preset range, superimpose echo signals of each transmission angle for a preset number of times, and output a superimposed target signal; a setting module configured to set a preset field window based on a receiving sequence of the echo signals of a plurality of angles acquired by the acquisition module; an accumulation module configured to, when the distance information of the detected object is greater than the preset range, acquire a similarity of adjacent angle echo data within the preset field window based on the acquisition module, and when the similarity is greater than a preset threshold, perform non-coherent accumulation based on the preset field window to obtain an accumulated target signal; and an adjustment module configured to, when the similarity is less than or equal to the preset threshold, adjust the preset field window based on the similarity value.

5. The apparatus of claim 4 wherein, The apparatus further comprises a storage module configured to determine a preset storage corresponding to the echo signal according to the multi-dimensional signal transmission angle and the signal receiving sequence of the echo signal, and store the echo signal in the corresponding preset storage.

6. The apparatus of claim 4, wherein, The acquisition module is further configured to acquire the multi-angle echo signal corresponding to the center field of view when the distance information of the detected object is greater than a preset range. The accumulation module is further configured to perform non-coherent accumulation on the multi-angle echo signal corresponding to the center field of view based on a preset field window to obtain an accumulated target signal. The acquisition module is further configured to acquire the multi-angle echo signal corresponding to the edge field of view. The superposition module is further configured to superimpose each transmission angle echo signal corresponding to the edge field of view to output a target signal corresponding to the superimposed edge field of view.

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