Data processing method of laser radar, laser radar, terminal equipment and medium

Abstract

The invention relates to a data processing method of a laser radar, the laser radar, terminal equipment and a medium. The lidar comprises a pixel array, the pixel array comprises a plurality of macro pixels, each macro pixel comprises a plurality of combined pixels, each macro pixel comprises a first number of pixels, and each combined pixel comprises a second number of pixels. The method comprises the following steps: generating a plurality of first histograms respectively corresponding to a plurality of macro pixels based on echoes of o times of detection scanning detected by a pixel array; in response to the situation that the signal intensity in the first histogram corresponding to the macro pixel exceeds a first detection threshold value, generating a plurality of second histograms respectively corresponding to a plurality of combined pixels in the macro pixel based on echoes of p times of detection scanning detected by the pixel array; and determining a distance and / or reflectivity of the object based on the plurality of second histograms.

Description

Technical Field

[0001] The present disclosure relates to the field of laser radar, and more specifically to a laser radar data processing method and a laser radar. The present disclosure also particularly relates to a terminal device including the above laser radar and a computer-readable storage medium storing a computer program capable of implementing the above method. Background Art

[0002] LiDAR is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of an object. It is an advanced detection method that combines laser technology with photoelectric detection technology. LiDAR is widely used in autonomous driving, transportation communications, drones, intelligent robots, resource exploration and other fields due to its advantages such as high resolution, good concealment, strong anti-active interference ability, good low-altitude detection performance, small size and light weight.

[0003] For data processing at the receiving end of the lidar, higher sampling accuracy and storage accuracy can provide more waveform information and higher detection accuracy, but it will bring greater sampling power consumption and storage resource area overhead. Summary of the invention

[0004] The purpose of the present disclosure is to overcome the above-mentioned and / or other problems in the prior art. It can dynamically adjust the resolution of the lidar, save detection power consumption and storage resources while maintaining good detection performance.

[0005] According to a first aspect of the present disclosure, a data processing method for a laser radar is provided, wherein the laser radar includes a pixel array, the pixel array includes a plurality of macro pixels, each macro pixel includes a plurality of combined pixels, each macro pixel includes a first number of pixels, and each combined pixel includes a second number of pixels, the method comprising: based on the echoes of o detection scans detected by the pixel array, generating a plurality of first histograms corresponding to the plurality of macro pixels respectively, wherein o is an integer greater than 0; in response to the signal intensity in the first histogram corresponding to the macro pixel exceeding a first detection threshold, based on the echoes of p detection scans detected by the pixel array, generating a plurality of second histograms corresponding to the plurality of combined pixels in the macro pixel respectively, wherein p is an integer greater than 0; and determining the distance and / or reflectivity of the object based on the plurality of second histograms.

[0006] Furthermore, the method also includes: superimposing the multiple second histograms with the first histogram respectively to generate a plurality of combined pixel histograms, and further determining the distance and / or reflectivity of the object based on the multiple combined pixel histograms.

[0007] Further, each of the combined pixels includes multiple superpixels, each superpixel contains a third number of pixels, wherein the method also includes: in response to the signal intensity in the combined pixel histogram corresponding to the combined pixel in the macropixel exceeding a second detection threshold, based on the echoes of q detection scans detected by the pixel array, generating multiple third histograms corresponding to the multiple superpixels in the combined pixel, respectively, wherein q is an integer greater than 0; and determining the distance and / or reflectivity of the object based on the multiple third histograms.

[0008] Further, each of the combined pixels includes multiple superpixels, each superpixel contains a third number of pixels, wherein the method also includes: in response to the signal intensity in the second histogram corresponding to the combined pixel in the macropixel exceeding a third detection threshold, based on the echoes of q detection scans detected by the pixel array, generating multiple third histograms corresponding to the multiple superpixels in the combined pixel, respectively, wherein q is an integer greater than 0; and determining the distance and / or reflectivity of the object based on the multiple third histograms.

[0009] Furthermore, the method also includes: respectively superimposing the multiple third histograms with the first histogram and the second histogram to generate multiple superpixel histograms, and further determining the distance and / or reflectivity of the object based on the multiple superpixel histograms.

[0010] Furthermore, the method further includes: determining an echo time according to the first histogram.

[0011] Furthermore, for the p detection scans, the multiple second histograms are generated in a time neighborhood of the echo moment.

[0012] Furthermore, during the p detection scans, the macro-pixel is activated and data is collected for the macro-pixel within a time neighborhood of the echo moment.

[0013] Further, the time bins of the first histogram are characterized by a first width to represent echo intensities detected during a first flight time range, and the time bins of the second histogram are characterized by a second width different from the first width to represent echo intensities detected during a second flight time range different from the first flight time.

[0014] Furthermore, the first width is greater than the second width.

[0015] Furthermore, the method also includes a denoising step, which includes removing noise floor values ​​in the first histogram, the combined pixel histogram and / or the superpixel histogram.

[0016] According to a second aspect of the present disclosure, a laser radar is provided, comprising: a transmitting unit; a pixel array, comprising a plurality of macropixels, each macropixel comprising a plurality of combined pixels, wherein each macropixel includes a first number of pixels, and each combined pixel includes a second number of pixels; a control unit, configured to: cause the transmitting unit to transmit laser pulses to the field of view of the laser radar; generate a plurality of first histograms corresponding to the plurality of macropixels respectively based on echoes of o detection scans detected by the pixel array, wherein o is an integer greater than 0; in response to a signal intensity in the first histogram corresponding to the macropixel exceeding a first detection threshold, generate a plurality of second histograms corresponding to the plurality of combined pixels in the macropixel respectively based on echoes of p detection scans detected by the pixel array, wherein p is an integer greater than 0; and determine the distance and / or reflectivity of the object based on the plurality of second histograms.

[0017] Furthermore, the pixel array includes multiple levels of pixel blocks, wherein a previous level of pixel blocks includes multiple next level of pixel blocks, wherein pixel blocks of different levels have different numbers of pixels, wherein the field of view of the laser radar includes a first area and a second area, wherein the pixel area corresponding to the first area in the pixel array has fewer levels of pixel blocks, and the pixel area corresponding to the second area in the pixel array has more levels of pixel blocks.

[0018] According to a third aspect of the present disclosure, a terminal device is provided, comprising the above-mentioned laser radar.

[0019] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores instructions, and the instructions implement the above method when executed by a processor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0021] Figure 1 An example of a histogram obtained from multiple detection scans of a laser radar is shown;

[0022] Figure 2 A schematic diagram of a detection module that can be used for a laser radar is shown;

[0023] Figure 3 The process of sampling and storage by the detection unit is shown;

[0024] Figure 4 is a flowchart of a data processing method of a laser radar according to an exemplary embodiment of the present disclosure;

[0025] Figure 5 is an example detection module of a laser radar according to an exemplary embodiment of the present disclosure;

[0026] Figure 6 shows a histogram obtained by performing a detection scan using macro pixels;

[0027] Figure 7 shows a histogram obtained by dividing a macro pixel into a plurality of composite pixels for detection scanning;

[0028] Figure 8 A schematic diagram showing a plurality of composite pixel histograms generated by respectively superimposing the first histogram with a plurality of second histograms;

[0029] Fig. 9 The generation of a second histogram of combined pixels in the time neighborhood of the echo moment is shown;

[0030] Fig.10 The generation of a third histogram of superpixels in the temporal neighborhood of the echo instant is shown;

[0031] Fig.11 A schematic diagram showing a plurality of third histograms being superimposed on the first histogram and the second histogram to generate a plurality of superpixel histograms;

[0032] Fig.12 A schematic diagram showing a histogram of high temporal resolution superimposed on a histogram of low temporal resolution;

[0033] Fig.13 A schematic diagram showing removal of the noise floor value in the first histogram is shown;

[0034] Fig.14 A schematic diagram showing the removal of noise floor values ​​in a composite pixel histogram; and

[0035] Fig.15 A schematic block diagram of a laser radar according to an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0036] The specific implementation methods of the present disclosure will be described below. It should be noted that in the specific description of these implementation methods, in order to provide a concise description, it is impossible for this specification to provide a detailed description of all the features of the actual implementation methods. It should be understood that in the actual implementation of any implementation method, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet system-related or business-related restrictions, various specific decisions are often made, and this will also change from one implementation method to another. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the content disclosed by the present disclosure, some changes in design, manufacturing or production based on the technical content disclosed in the present disclosure are just conventional technical means, and should not be understood as insufficient content of the present disclosure.

[0037] Unless otherwise defined, the technical or scientific terms used in the claims and the specification shall have the usual meaning understood by persons with ordinary skills in the technical field to which the present disclosure belongs. The words "first", "second" and similar words used in the patent application specification and the claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "one" or "one" do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalent elements, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0038] In the present disclosure, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution. In the present disclosure, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0039] In the description of the embodiments of the present disclosure, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0040] The data processing method of the laser radar provided according to the embodiment of the present disclosure is described in detail below with reference to the accompanying drawings.

[0041] Laser radar (light detection and ranging, LiDAR) is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of an object. Laser radar, also known as laser radar or LADAR, works by emitting a detection signal (laser beam) to the object, and then comparing the received signal (echo) reflected from the object with the transmitted signal. After appropriate processing, relevant information about the object can be obtained. For example, parameters such as object distance, direction, height, speed, attitude, and even shape. The laser radar may include a transmitting end and a receiving end. The transmitting end collimates and shapes the outgoing light of the transmitter through the transmitting optical system and projects it into the detection field of view. The receiving end receives the echo signal reflected by the outgoing light from the object through the receiving optical system and the receiver. The transmitter can be deployed on a transmitting circuit board or a transmitting chip, and the receiver can be deployed on a receiving circuit board or a receiving chip. In the present disclosure, the laser radar can be replaced by other active detection devices that measure the position, speed and other information of the object by emitting signals to the object and receiving signals reflected from the object.

[0042] Single Photon Avalanche Diode (SPAD) is an avalanche photodiode operating in Geiger mode. When the reverse bias voltage across the SPAD is greater than its avalanche breakdown voltage, the internal electric field is extremely strong, the photogenerated carriers gain a large amount of kinetic energy, and the impact ionization will continue to produce an avalanche multiplication effect. Therefore, a single photon can make the avalanche photodiode reach saturation photocurrent. SPAD has extremely high gain and sensitivity, and is often used for single photon detection, which has great advantages in the field of laser ranging.

[0043] The core technology of using SPAD for ToF ranging is time-correlated single photon counting (TCSPC), the basic idea of ​​which is to regard photons as random events and perform statistics after repeated measurements of photons for multiple cycles. When the light signal is very weak and the detection frequency is very high, photons may not be detected in some cycles, and one photon may be detected in some cycles. The detection time of the photon is corresponded to a certain time period. In this way, after a large number of repeated measurements, the number of photons in each time period is counted to obtain a frequency distribution histogram of photons changing with time, and the intensity change of the light signal can be obtained by fitting the histogram. By analyzing the histogram, the return time of the echo can be obtained, and the time of flight (ToF) can be obtained by subtracting the emission time from the return time.

[0044] In the TCSPC (time-correlated single photon counting) system, it is necessary to sample the SPAD triggering behavior within the ToF time in multiple measurements, accumulate and store it in the storage resource in the form of a histogram, and obtain a histogram waveform with a signal-to-noise ratio that meets the requirements after multiple measurements.

[0045] When laser radar detects obstacles in the same field of view, it can perform multiple repeated measurements during one detection process, and one measurement can be called a scan. That is, a laser can emit light multiple times during its emission time, and each emission is called a scan. Each scan emits one detection pulse (the number of repeated measurements can reach 400-500 times, or even thousands of times, or more or less times). Figure 1 As shown in the figure, during a detection process of the laser radar, for example, a total of 400 scans are performed (scan 1, scan 2, scan 3, ..., scan 400). During each scan, the detection pulse emitted during the scan is reflected by the obstacle and the echo generated by the ambient light noise, etc., which will trigger different numbers of SPADs at different times ( Figure 1 The horizontal axis is time, and the vertical axis is the number of triggered SPADs. Based on the results of the previous scan, the results of this scan are continuously accumulated, so that the number of times the photons trigger the SPAD can be counted after repeated scans, and a histogram waveform of the number of photons changing with time can be obtained (i.e. Figure 1 The histogram on the right side of the figure shows that the echo signal of the obstacle will accumulate a higher number at the time corresponding to the obstacle, so that a stronger peak can be accumulated at the time corresponding to the obstacle. Through peak analysis, information such as the distance of the obstacle can be obtained. The scale of the horizontal axis of the histogram is time information, and the scale width on the time axis can be equal to the resolution of the time digital converter in the laser radar, or it can be the resolution of the sampling time.

[0046] Figure 2A schematic diagram of a detection module that can be used for a laser radar is shown. The detection module 10 includes a plurality of detection units 15. Each detection unit 15 includes a plurality of (e.g., 16 as shown, or more, such as 20, 32, 48, 96, etc., or fewer, such as 2, 4, 10, etc.) pixels 150, and the pixel 150 can be a SPAD, or a single-photon photodetector similar to a SPAD, or a silicon photomultiplier tube (SiPM), etc. The output end of the pixel 150 of each detection unit 15 is connected to a readout circuit (e.g., a time-to-digital converter TDC) 16, and the range of the detection window of each detection unit 15 (i.e., the time period during which the SPAD can sense incident photons) is independently adjustable, that is, each detection unit 15 can be independently controlled to be in an activated state (e.g., the SPAD is in Geiger mode, i.e., a reverse bias voltage greater than the breakdown voltage is applied to the SPAD, so that the SPAD can trigger an avalanche effect when receiving a photon) or a deactivated state (e.g., a state in which the SPAD cannot be triggered to avalanche by a photon). After the photons are incident on the detection unit 15, one or more pixels are triggered and an electrical signal is generated. Each detection unit 15 is coupled to a readout circuit 16, which can determine the number of pixels triggered in the detection unit 15 and the triggering time. According to the triggering time, the triggering number is sequentially stored in the memory 17.

[0047] Multiple pixels 150 in the detection unit 15 can share a set of readout circuits 16 and memory 17 (in Figure 2 In the example, the four pixels 150 in the detection unit 15 can share a set of readout circuits 16 and memory 17), and the data of multiple pixels 150 can be accumulated and output. If the number of pixels 150 in the detection unit 15 is smaller (in the extreme case, it can only contain one pixel 150), the spatial resolution of the detection module 10 will be higher, but it will also be accompanied by an increase in sampling power consumption and storage resources. As the detection array expands, this will bring great power consumption pressure.

[0048] by Figure 2 Taking the detection unit 15 shown in the figure as an example, the first set of detection data obtained in the process of n detection scans includes the time information obtained in each detection scan and the intensity information corresponding to the time information. The time information is the triggering moment when the photon triggers one or more pixels in the detection unit. The intensity information can represent the number of pixels triggered at the triggering moment, that is, the intensity of the light signal is represented by the number of triggered pixels. The first set of detection data is, for example, Figure 1 As shown, for each detection scan, the triggering time of the pixel and the number of pixels triggered each time can be known.

[0049] Reference Figure 3, which shows the sampling and storage process of the detection unit 15. Each scan samples the number of pixel triggers according to the periodic time sequence T1, T2, T3, ... In the memory, a storage location (S1, S2, S3, ...) can be allocated for each sampling moment (T1, T2, T3, ...), and each storage location can store the number of pixels triggered at the sampling moment. In this way, the trigger data can be stored in the storage location corresponding to the sampling moment in sequence. For example, the number of pixels triggered at the time of the first scan (scan 1) is cnt11 (taking the detection unit 15 including 16 pixels as an example, the number of triggers can be an integer between 0-16), cnt11 is stored in the storage location S1 corresponding to the time of T1; the number triggered at the time of T2 is cnt21, and cnt21 is stored in the storage location S2 corresponding to the time of T2; ... In the second scan (scan 2), the number of pixels triggered at time T1 is cnt12, the number triggered at time T2 is cnt22, ..., and then the trigger data can be accumulated on the basis of the trigger data of the previous scan and then stored in the storage locations corresponding to the sampling times in sequence, for example, the storage data in the storage location S1 corresponding to time T1 is updated to cnt11+cnt12; in the third scan (scan 3), the number of pixels triggered at time T1 is cnt13, the number triggered at time T2 is cnt23, ..., and then accumulated and stored, for example, the storage data in the storage location S1 corresponding to time T1 is updated to cnt11+cnt12+cnt13. After completing all the repeated scans, the detection data corresponding to each sampling moment can be obtained, that is, the histogram waveform. It can be understood that when the number of incident photons is more, the number of pixels triggered is also more, and a higher value will be accumulated at this moment, and when the number of incident photons is less, the number of pixels triggered is also less, and a lower value will be accumulated at this moment. The histogram waveform can reflect the echo signal received within the detection time window of the detection unit 15.

[0050] In the existing scheme, during the entire detection process (multiple scanning processes), a fixed detection unit 15 is maintained for sampling and storage. In order to obtain a higher spatial resolution, each detection unit 15 contains a smaller number of pixels, which will lead to an increase in sampling power consumption and storage resources. However, in many application scenarios, objects may not exist in the object area for a long time. In this case, if the laser radar is always scanning with a higher spatial resolution, it will obviously increase a lot of unnecessary sampling power consumption and storage resource consumption. In view of the above situation, the present disclosure proposes a scheme for dynamically adjusting the detection resolution of the detection module. Specifically, during the process of multiple scanning accumulations, the scheme can dynamically adjust the sampling resolution, first perform echo sampling and signal accumulation at a low resolution, and when an echo that meets the signal-to-noise ratio requirement is found, perform high-resolution detection, and obtain relevant information of the object based on the histogram obtained by the high-resolution detection, such as the distance, resolution, speed and other information of the object.

[0051] See also Figures 4 to 5 . Figure 4 4 is a flowchart of a laser radar data processing method 400 according to an exemplary embodiment of the present disclosure. Figure 5 Detailed Description of the Invention ...

[0052] like Figure 5 As shown, the detection module 500 includes a pixel array 510. The pixel array 510 may include a plurality of macro pixels 511. Each macro pixel 511 may include a plurality of combined pixels 521. Each macro pixel 511 may include a first number of pixels 150. Each combined pixel 521 may include a second number of pixels 150. In some embodiments of the present disclosure, no pixels are shared between the plurality of macro pixels 511, and no pixels are shared between the plurality of combined pixels 521. As an example, Figure 5 Each macro pixel 511 shown in FIG. 5 includes 16 pixels 150 (eg, 16 SPADs) and 4 combined pixels 521 , and each combined pixel 521 includes 4 pixels 150 (eg, 4 SPADs).

[0053] In some other embodiments of the present disclosure, pixels 150 may be shared between multiple macro pixels 511, which means that at least two macro pixels 511 contain some identical pixels 150; or, pixels 150 may be shared between multiple combined pixels 521, which means that at least two combined pixels 521 contain some identical pixels 150. This allows pixel reuse with a high utilization rate, and is suitable for scenarios where the field of view corresponding to one macro pixel 511 or combined pixel 521 overlaps with the field of view corresponding to another macro pixel 511 or combined pixel 521.

[0054] Each macro pixel 511 or each composite pixel 521 can be used as an independent detection unit to perform the following operations: Figure 3 In some embodiments of the present disclosure, the detection module 500 may include a readout circuit and a memory connected to each detection unit (ie, macro pixel 511 or combined pixel 521). Figure 5 As shown, each macro pixel 511 and each combined pixel 521 can use a set of readout circuits 16 and memories 17 separately.

[0055] The method 400 may include the following steps S410 to S450 .

[0056] In step S410, a plurality of first histograms respectively corresponding to a plurality of macro pixels are generated based on the echoes of o detection scans detected by the pixel array, where o is an integer greater than 0.

[0057] Specifically, multiple scans are performed during one detection process, and the echo data detected by the pixel array during each scan process is continuously accumulated on the echo data detected during the historical scan process. Based on the echoes of the o detection scans detected by the pixel array, the trigger data of multiple pixels in each macro pixel 511 can be accumulated and stored in the corresponding storage location to obtain the corresponding first histogram. For example, during one scan process, each macro pixel 511 includes 16 pixels, and the trigger data of the 16 pixels are accumulated and stored in the storage location corresponding to the macro pixel 511; during the next scan process, the trigger data of the 16 pixels in the macro pixel 511 is accumulated to obtain the trigger data of the macro pixel 511, and then the trigger data of the macro pixel 511 is accumulated to the storage location, so that the first histogram corresponding to the macro pixel is obtained after o detection scans. The pixel array includes multiple macro pixels, so that multiple first histograms can be generated. The first histogram is generated based on macro pixels, and each macro pixel 511 corresponds to a relatively large area in the field of view of the detection module 500, and the first histogram has a relatively low spatial resolution.

[0058] In step S430, in response to the signal strength in the first histogram corresponding to the macropixel exceeding the first detection threshold, multiple second histograms corresponding to multiple pixels in the macropixel are generated based on the echoes of p detection scans detected by the pixel array, where p is an integer greater than 0.

[0059] Specifically, after each scan to obtain the histogram data, the histogram data in the corresponding memory of each macro pixel 511 can be read to perform waveform analysis. Figure 6After completing o times (for example, 100 times) of scanning, if an echo exceeding the signal-to-noise ratio threshold (or exceeding the detection threshold) is found in the first histogram of one or some macropixels 511 (which means that there is an object in the field of view corresponding to the macropixel 511), then for the macropixel 511, it is possible to switch to using multiple combined pixels 521 contained in the macropixel 511 for data sampling and storage, that is, in the subsequent detection process, the trigger data of multiple pixels in each combined pixel 521 are accumulated and stored in the corresponding storage location to obtain the corresponding second histogram. Each combined pixel 521 includes a smaller number of pixels than each macropixel 511, and each combined pixel 521 corresponds to a relatively smaller area in the field of view of the detection module 500 than each macropixel 511. The second histogram has a higher spatial resolution than the first histogram. For the macropixel 511 that does not detect an echo exceeding the signal-to-noise ratio threshold (or exceeding the detection threshold), the macropixel 511 can still be used as a detection unit for detection. In this way, more detailed detection is only required within the pixel array range corresponding to the object, rather than maintaining detailed detection globally (even in areas without objects), which greatly reduces power consumption and storage resources.

[0060] For example, in Figure 5 In the detection module 500 of the laser radar shown in the figure, for the macro pixel 511 (including 16 pixels) that detects the echo, for the subsequent p scans (for example, the 101st to 200th scans (scans 101-200)), the four combined pixels 521 (including 4 pixels each) included in the macro pixel 511 can be used to perform data sampling and storage. Figure 7 After p scans (for example, the 101st to 200th scans), the trigger data of the four combined pixels 521 are respectively stored in the storage positions corresponding to the combined pixels 521, and then the second histograms corresponding to the four combined pixels 521 can be obtained respectively.

[0061] In step S430 , the distance and / or reflectivity of the object is determined based on the plurality of second histograms.

[0062] Specifically, object analysis can be performed based on the second histogram, for example, the flight time of the echo pulse can be calculated based on the corresponding second histogram, and then the distance and / or reflectivity of the object can be determined to generate a point cloud. Compared with the point cloud generated based on the first histogram, the point cloud generated based on the second histogram has a higher point density (there are more sampling points in the point cloud), which can provide more information and finer details, and can more accurately represent the shape and surface features of the object.

[0063] The above describes the data processing method of the laser radar according to the exemplary embodiment of the present disclosure. By adopting this method, the spatial resolution of the detection module of the laser radar can be dynamically adjusted, so that the detection module first uses a larger macro pixel for detection to generate a first histogram, and then adjusts the spatial resolution of the sampling according to the first histogram. For the macro pixel with a strong received echo signal, the smaller combined pixel in the macro pixel is used for fine detection. At the same time, the area with weak echo signal intensity can still be detected with a larger macro pixel, so that while reducing power consumption, it also maintains a strong detection capability for objects with weak echo signals (the data of multiple pixels in the same detection unit are accumulated and output together, so the more the number of accumulated pixels, the stronger the detection capability for weak echo signals). This can save the detection power consumption and storage resources of the detection module while improving the detection resolution of the object, and ensure the optimal state of detection performance within the full field of view.

[0064] In some embodiments of the present disclosure, the flight time of the echo pulse may be further calculated based on both the first histogram and the second histogram, and then the distance and / or reflectivity of the object may be determined.

[0065] For example, the first histogram of the macro pixel 511 that detects the echo can be superimposed with the multiple second histograms of the multiple combined pixels 521 in the macro pixel 511 to generate multiple combined pixel histograms, and then the distance and / or reflectivity of the object can be determined based on the multiple combined pixel histograms. Specifically, the histograms can be superimposed by adding the number of pixel triggers at a specific sampling time in the first histogram to the number of pixel triggers at the corresponding sampling time in the second histogram. Figure 8 , which shows a schematic diagram of multiple combined pixel histograms generated by superimposing the first histogram with multiple second histograms. It can be understood that the combined pixel histogram is obtained by accumulating the second histogram of the corresponding combined pixel 521 on the basis of the first histogram of the macro pixel 511, so the detection results of the 1st to 200th scans will be reflected in the combined pixel histogram. Compared with the accuracy switching scheme in the prior art, which will lose the histogram data before the switching, this method will not lose the results obtained by the previous detection (the results of the original o detections), thereby avoiding the reduction of the signal-to-noise ratio because the combined pixel histogram contains more data.

[0066] In some embodiments of the present disclosure, the macropixel 511 can be subdivided throughout the detection time, so that continued detection can be performed with a higher spatial resolution within the field of view where the obstacle is detected. In other words, if o scans find that the macropixel 511 has an object echo exceeding the threshold, the macropixel 511 is subdivided into detection units (divided into multiple combined pixels 521), and multiple combined pixels 521 are used to continue scanning, so as to obtain a more refined scanning result, and identify objects with higher spatial resolution in the object area (or strong echo object area). At the same time, for the macropixel 511 whose echo signal does not exceed the threshold, continue to detect with the macropixel as the detection unit to improve the signal-to-noise ratio of the field of view detection corresponding to the macropixel, ensure the effective identification of weak echo objects, and reduce system power consumption. Furthermore, in the subsequent scanning process, the echo signal strength in the histogram can be continuously analyzed. When the echo signal strength corresponding to any macropixel exceeds the threshold, the macropixel can be further subdivided, thereby achieving dynamic adjustment of spatial resolution, signal-to-noise ratio, system power consumption, and storage resources during the entire detection process, so as to optimize the overall detection performance of the lidar.

[0067] In some embodiments of the present disclosure, method 400 may further include a step of determining the echo time according to the first histogram. For example, the time information corresponding to the echo may be obtained by using the first histogram to calculate the center of gravity or the front time. Figure 6 As shown, the echo time t0 can be determined in the first histogram obtained by accumulating o scans of the macro pixel 511.

[0068] In some embodiments of the present disclosure, it is preferred to perform macro pixel subdivision in the time neighborhood of the echo time t0, that is, for the subsequent p detection scans, multiple second histograms can be generated in the time neighborhood of the echo time t0. Fig. 9 , which shows about Figure 7 For the four combined pixels 521 described above, for p detection scans, data of each combined pixel 521 is collected and stored only in the time neighborhood (t0-a, t0+a) of the echo time t0, thereby generating a corresponding second histogram. In this way, fine sampling is performed only in the time neighborhood corresponding to the distance between the object and the laser radar, which can further save sampling power consumption and storage resources. It should be noted that although Fig. 9 The time neighborhood shown is centered on the echo time t0, but it may not be centered on the echo time t0, as long as the superimposed preset window includes the echo time t0. According to some embodiments of the present disclosure, the echo time t0 may be widened to the left and right by a certain proportion, such as 10% or 20%, respectively, as an adjusted detection window.

[0069] In some embodiments of the present disclosure, during p times (e.g., the 101st to 200th) of detection scanning, the macro pixel 511 that detects the echo may be activated only within the time neighborhood of the echo moment, and data may be collected for the macro pixel 511. At the moment beyond the echo time neighborhood range, the macro pixel 511 may be used to collect data, or data may not be collected (e.g., the pixel may be turned off or data may not be collected and stored), so as to further reduce power consumption and storage resource consumption.

[0070] In some embodiments of the present disclosure, each composite pixel 521 may further include a plurality of superpixels, each superpixel including a third number of pixels. Each superpixel may also be used as an independent detection unit to perform the following steps: Figure 3 As an example, in Figure 5 In the detection module 500 shown, each combined pixel 521 may include two superpixels 531, and each superpixel includes two pixels 150. Each superpixel may use a set of readout circuits and memory ( Figure 5 ). Thus, the method 400 may further include the following steps: in response to the signal strength in the combined pixel histogram corresponding to the combined pixel 521 in the macro pixel 511 exceeding the second detection threshold, or in response to the signal strength in the second histogram corresponding to the combined pixel 521 in the macro pixel 511 exceeding the third detection threshold, based on the echoes of q detection scans detected by the pixel array, generate multiple third histograms corresponding to the multiple super pixels 531 in the combined pixel 521, respectively, where q is an integer greater than 0; and based on the multiple third histograms, determine the distance and / or reflectivity of the object. The second detection threshold and the third detection threshold may be system-set in advance, or may be adjusted in real time according to the number of scans and the noise amplitude.

[0071] For example, in Figure 5 , Figure 7 and Figure 8 In the example of the second histogram or the combined pixel histogram of the four combined pixels 521 shown, for the combined pixel 2 and the combined pixel 4 that detect the echo, for the subsequent q scans (for example, the 201st to 300th scans (scans 201-300)), the two super pixels 531 (each having 2 pixels) contained in the combined pixel 2 and the two super pixels 531 (each having 2 pixels) contained in the combined pixel 4 can be used to perform data sampling and storage, thereby generating a third histogram with higher spatial resolution.

[0072] In some embodiments of the present disclosure, the distance and / or reflectivity of an object can be determined based on multiple third histograms. Specifically, object analysis can be performed based on the third histogram, for example, the flight time of the echo pulse can be calculated based on the corresponding third histogram, and then the distance and / or reflectivity of the object can be determined to generate a point cloud. Compared with the point cloud generated based on the first histogram and / or the second histogram, the point cloud generated based on the third histogram has a higher point density (there are more sampling points in the point cloud), which can provide more information and finer details, and can more accurately represent the shape and surface features of the object.

[0073] In some embodiments of the present disclosure, the combined pixel 521 may be subdivided throughout the detection time, so that continued detection can be performed at a higher spatial resolution within the field of view where an obstacle is detected. In other words, if p scans find that the combined pixel 521 has an object echo exceeding the signal-to-noise ratio threshold, the combined pixel 521 is pixel-subdivided (subdivided into multiple superpixels 531) and continued scanning is performed at a higher spatial resolution.

[0074] In some embodiments of the present disclosure, the echo time t1 may be determined in the second histogram accumulated from the p scans of the combined pixel 2 or the combined pixel 4. Preferably, the combined pixel 521 may be subdivided within the time neighborhood of the echo time t1, that is, for the subsequent q detection scans, multiple third histograms may be generated within the time neighborhood of the echo time t1. Fig.10 , which shows about Figure 7 The combined pixel 2 and the combined pixel 4 described, for the 201st to 300th detection scans, only collect and store data for each superpixel 531 in the time neighborhood (t1-b, t1+b) of the echo time t1, thereby generating a corresponding third histogram. The third histogram has a higher spatial resolution than the second histogram, because each superpixel 531 corresponds to a relatively smaller area in the field of view of the detection module 500. For the combined pixel 1 and the combined pixel 2 that do not detect an echo exceeding the signal-to-noise ratio threshold (or exceeding the detection threshold), the corresponding combined pixel can still be used as a detection unit for detection.

[0075] In some embodiments of the present disclosure, during q detection scans, the superpixel 531 that detects the echo can be activated and data can be collected for the superpixel 531 only within the time neighborhood of the echo moment. At the moment beyond the echo time neighborhood range, the combined pixel 521 can be used to collect data, or data can be not collected (for example, the pixel is turned off or data collection and storage are not performed), so as to further reduce power consumption and storage resource consumption.

[0076] In some embodiments of the present disclosure, the first histogram, the second histogram, and the third histogram may be further used to determine the Figure 3 or determine the distance and / or reflectivity of an object.

[0077] For example, the combined pixel histogram of the combined pixel 521 where the echo is detected can be superimposed with multiple third histograms of multiple superpixels 531 in the combined pixel 521 to generate multiple superpixel histograms, and then the distance and / or reflectivity of the object can be determined based on the multiple superpixel histograms. The histograms can be superimposed by adding the number of pixel triggers at a specific sampling time in the third histogram to the number of pixel triggers at the corresponding sampling time in the combined pixel histogram. Fig.11 , which shows a schematic diagram of superimposing multiple third histograms with the first histogram and the second histogram to generate multiple superpixel histograms. It can be understood that the superpixel histogram is obtained by accumulating the third histogram of the corresponding superpixel 531 on the basis of the first histogram of the macropixel 511 and the second histogram of the combined pixel 521, so all (including o times, p times, q times) scanning detection results will be reflected in the superpixel histogram. Compared with the accuracy switching scheme in the prior art that loses the histogram data before the switch, this method can avoid losing the results obtained by the previous detection (the original o+p detection results will not be lost), thereby avoiding the reduction of the signal-to-noise ratio because the superpixel histogram contains more data.

[0078] In some embodiments of the present disclosure, similar to the subdivision method of macro pixels or composite pixels described above, the pixel array can be subdivided into detection units multiple times until the pixel level is reached. In other words, the pixel array can be dynamically subdivided into detection units in real time according to the results of the current detection scan, and then for subsequent detection scans, the subdivided detection units can be used to generate a subdivided histogram or cumulative histogram, and then based on the subdivided histogram or cumulative histogram, it is determined whether to further subdivide the pixel array into detection units, and generate a further subdivided histogram or cumulative histogram, and so on. The principle of the degree of subdivision can be achieved until a single pixel is a detection unit. In actual use, it can be specifically set according to system requirements and radar performance requirements. In this way, continuous dynamic adjustment of spatial resolution following the actual scene can be achieved during a detection process.

[0079] In some embodiments of the present disclosure, different time resolutions (i.e., quantization time accuracy / storage time resolution of the readout circuit) may be used for sampling and storage of the macropixel 511 and the combined pixel 521. Specifically, for o detection scans of the macropixel 511, low time resolution may be used for sampling and storage. After o scans, an echo that meets the signal-to-noise ratio requirement is found at time t0, then in the neighborhood of t0 (t0-a, t0+a), for p detection scans of the combined pixel 521, high time resolution may be used for sampling and storage. A histogram with high time resolution may be directly superimposed on a histogram with low time resolution. For example, the histogram may be superimposed by adding the number of pixel triggers at a specific sampling moment in a high time resolution histogram to the number of pixel triggers in the time interval in which the specific sampling moment is located in a low time resolution histogram.

[0080] See also Fig.12 , which shows a schematic diagram of a histogram with high time resolution superimposed on a histogram with low time resolution. In a detection process, based on the detection results of the previous o scans (for example, the 1st to the 100th (scan 1-100)), a first histogram of a macropixel 511 can be obtained. The time bin 1201 of the first histogram can be characterized by a first width d1 to represent the echo intensity detected during the first flight time range (for example, 4ns). After completing o scans, if an echo exceeding the signal-to-noise ratio threshold (or exceeding the detection threshold) is found at time t0 of the first histogram of one or some macropixels 511 (meaning that there is an object in the field of view corresponding to the macropixel 511), then for the macropixel 511, it can be switched to use the multiple combined pixels 521 contained in the macropixel 511 for data sampling and storage, that is, in the subsequent detection process (including p scans), the trigger data of multiple pixels in each combined pixel 521 are accumulated and stored in the corresponding storage location to obtain the corresponding second histogram. The time bins 1202 of the second histogram may be characterized by a second width d2 different from the first width d1 to represent echo intensities detected during a second time-of-flight range (eg, 1 ns). The first width d1 may be greater than the second width d2.

[0081] exist Fig.12In the example, for the 1st to 100th scans (scans 1-100), the macropixel 511 is sampled and stored with a time period of 4ns, and the first histogram reflects the number of pixels triggered at each sampling moment (4ns, 8ns, 12ns, 16ns, ...) (it can be understood that the data stored in each time box in the first histogram is the trigger data within a certain time interval, for example, the first time box can store the trigger data of the corresponding macropixel within the time range of 0-4ns, and the second time box can store the trigger data of the corresponding macropixel within the time range of 4-8ns, ...). If an echo exceeding the signal-to-noise ratio threshold (or exceeding the detection threshold) is found at time t0 (for example, 12ns) of the first histogram. Afterwards, in the neighborhood of 8-16ns of t0 (12ns), the combined pixel 521 in the macropixel 511 is sampled and stored with a time period of 1ns, and the second histogram reflects the number of pixels triggered at each sampling moment (8ns, 9ns, 10ns, ..., 16ns). As shown in the figure, the superposition of histograms with different time resolutions can be achieved by adding the number of pixel triggers at specific sampling moments (9ns, 10ns, 11ns, 12ns) in the second histogram to the number of pixel triggers in the time interval (between 8ns and 12ns, that is, the first histogram at the sampling moment 12ns) where the specific sampling moment is located in the first histogram, and by adding the number of pixel triggers at specific sampling moments (for example, 13ns, 14ns, 15ns, 16ns) in the second histogram to the number of pixel triggers in the time interval (between 12ns and 16ns, that is, the first histogram at the sampling moment 16ns) where the specific sampling moment is located in the first histogram.

[0082] In order to reduce the use of storage resources, method 400 may also include a denoising step. For example, the noise floor of the histogram may be dynamically removed as the scan progresses, that is, the accumulated floor noise in the histogram is removed once every n scans, thereby reducing the amount of data without affecting signal superposition.

[0083] In some embodiments of the present disclosure, the denoising step may include removing the noise floor value in the first histogram, the combined pixel histogram, and / or the superpixel histogram. For example, after the detection scan is performed o times, the noise floor may be determined based on the noise level of the entire detection time window of the first histogram, and the noise floor value may be subtracted from the accumulated data as the basis for subsequent accumulation, such as Fig.13 After continuing to detect and scan for p times, the noise floor can be determined based on the noise level of the entire detection time window of the pixel histogram, and the noise floor value is subtracted from the accumulated data as the basis for subsequent accumulation, as shown in Fig.14After continuing to detect and scan for q times, the noise floor can be determined based on the noise level of the entire detection time window of the superpixel histogram, and the noise floor value is subtracted from the accumulated data as the basis for subsequent accumulation.

[0084] In some embodiments of the present disclosure, dynamically adjusting the spatial resolution and the temporal resolution can be used in combination with the denoising step. For example, first use a large macro pixel 511 and a low temporal resolution for sampling or storage, and when an echo exceeding a signal-to-noise ratio threshold is identified, use a small composite pixel 521 and use a high temporal resolution to sample and store data, and at the same time, deduct the noise floor when each echo is counted.

[0085] Although the exemplary embodiments of the present disclosure use SPAD as an example to illustrate time information and intensity information, it is easy for those skilled in the art to understand that the present disclosure is not limited thereto, and other types of photodetectors may also be used, including but not limited to avalanche photodiodes APD, silicon photomultipliers SiPM, etc. For different photodetectors, different parameters may be used to characterize intensity information. For example, if the photodetector is a SPAD array, the number of SPADs triggered simultaneously corresponding to the time information may be used as the intensity information; if the photodetector is a SiPM, the output level / current intensity corresponding to the time information may be used to represent the intensity information of the optical signal.

[0086] According to another exemplary embodiment of the present disclosure, a laser radar is also provided.

[0087] like Fig.15 As shown, the laser radar 1500 may include a transmitting unit 1510, a pixel array 1520 and a control unit 1530.

[0088] The transmitting unit 1510 can provide a detection light beam 1501 to the target space to illuminate the object 20 in the space. At least part of the detection light beam 1501 is reflected by the object 20 to form an echo light beam 1502. At least part of the light signal (such as photons) of the echo light beam 1502 is collected by the pixel array 1520. The control unit 1530 is respectively connected to the transmitting unit 1510 and the pixel array 1520, and the trigger signals of the synchronous transmitting unit 5101 and the pixel array 1520 are used to calculate the time required for the light beam to be emitted by the transmitting unit 1510 and received by the pixel array 1520, that is, the flight time.

[0089] Specifically, the pixel array 1520 may be as described above with reference to Figure 5The described pixel array 510 may include multiple macro pixels, each macro pixel includes multiple combined pixels. Each macro pixel includes a first number of pixels, and each combined pixel includes a second number of pixels. The control unit 1530 may be configured to: enable the transmitting unit 1510 to emit laser pulses to the field of view of the laser radar 1500; based on the echoes of the o detection scans detected by the pixel array 1520, generate multiple first histograms corresponding to the multiple macro pixels, where o is an integer greater than 0; in response to the signal intensity in the first histogram corresponding to the macro pixel exceeding the first detection threshold, based on the echoes of the p detection scans detected by the pixel array, generate multiple second histograms corresponding to the multiple combined pixels in the macro pixel, where p is an integer greater than 0; and determine the distance and / or reflectivity of the object based on the multiple second histograms. The details of the operation of the control unit 1530 are the same or similar to the method 400 described above, and will not be repeated here.

[0090] In some embodiments of the present disclosure, the pixel array 1520 may include multiple levels of pixel blocks (eg, Figure 5 The described pixel array 510 includes three levels of pixel blocks, namely macro pixels, composite pixels and super pixels, and may also include more levels), and each pixel block in each level of pixel blocks can be used as an independent detection unit. The pixel blocks of the previous level include multiple pixel blocks of the next level, and the pixel blocks of different levels have different numbers of pixels. The field of view of the laser radar 1500 may include a first area and a second area. The pixel area corresponding to the first area in the pixel array 1520 may have fewer levels of pixel blocks, and the pixel area corresponding to the second area in the pixel array 1520 may have more levels of pixel blocks.

[0091] As an example, when the laser radar 1500 is deployed on a vehicle, the first area may be an area with relatively few objects, such as a sky area, and the second area may be an area of ​​interest of the vehicle, which may refer to an area where there may be more objects. In this case, the pixel area corresponding to the first area in the pixel array 1520 may have n-level pixel blocks, and the pixel area corresponding to the second area in the pixel array 1520 may have m-level pixel blocks, where n and m are integers greater than 1, and n <m。

[0092] According to another exemplary embodiment of the present disclosure, a terminal device is also provided. The terminal device may include the laser radar as described above. The terminal device may be a vehicle (e.g., a smart car), a surveying and mapping device, an aircraft (e.g., a drone), a ship, etc.

[0093] The technology described herein can be implemented in hardware, software, firmware, or any combination thereof, unless specifically described as being implemented in a particular manner. Any features described as modules or components can also be implemented together in an integrated logic device, or separately implemented as discrete but interoperable logic devices. If implemented in software, the technology can be implemented at least in part by a non-transient processor-readable storage medium including instructions, and when the instructions are executed, one or more of the above methods are executed. The non-transient processor-readable data storage medium can form a part of a computer program product that may include packaging materials. The program code can be implemented in a high-level procedural programming language or an object-oriented programming language to communicate with a processing system. If necessary, the program code can also be implemented in assembly language or machine language. In fact, the mechanism described herein is not limited to the scope of any particular programming language. In any case, the language can be a compiled language or an interpreted language.

[0094] One or more aspects of at least some embodiments may be implemented by representative instructions stored on a machine-readable medium that represent various logic within a processor, which when read by a machine causes the machine to fabricate logic for performing the techniques described herein.

[0095] Such machine-readable storage media may include, but are not limited to, a non-transitory tangible arrangement of articles manufactured or formed by a machine or apparatus, including storage media such as: a hard disk; any other type of disk, including floppy disks, optical disks, compact disk-read only memory (CD-ROM), compact disk-rewritable (CD-RW), and magneto-optical disks; semiconductor devices, such as read-only memory (ROM), random access memory (RAM) such as dynamic random access memory (DRAM) and static random access memory (SRAM), erasable programmable read-only memory (EPROM), flash memory, electrically erasable programmable read-only memory (EEPROM); phase change memory (PCM); magnetic or optical cards; or any other type of medium suitable for storing electronic instructions.

[0096] So far, the data processing method and laser radar according to the present disclosure have been described, and a terminal device including the laser radar and a computer-readable storage medium have also been introduced.

[0097] Through the present disclosure, the detection resolution (spatial resolution and / or temporal resolution) of the laser radar can be dynamically adjusted to save the detection power consumption and storage resources of the detection module. Furthermore, the histogram after adjusting the detection resolution can be obtained by superimposing the original histogram, without losing the detection results before the adjustment, thereby avoiding reducing the signal-to-noise ratio.

[0098] Some exemplary embodiments have been described above. However, it should be understood that various modifications may be made to the exemplary embodiments described above without departing from the spirit and scope of the present disclosure. For example, if the described techniques are performed in a different order and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways and / or replaced or supplemented by other components or their equivalents, suitable results may be achieved, and accordingly, these modified other implementations also fall within the scope of protection of the claims.

Claims

1. A method for processing laser radar data, wherein the laser radar comprises a pixel array, the pixel array comprises a plurality of macro pixels, each macro pixel comprises a plurality of composite pixels, each macro pixel comprises a first number of pixels, each composite pixel comprises a second number of pixels, the method comprising: Based on the echoes of o detection scans detected by the pixel array, generate a plurality of first histograms respectively corresponding to the plurality of macro pixels, wherein o is an integer greater than 0; In response to the signal intensity in the first histogram corresponding to the macropixel exceeding a first detection threshold, generating a plurality of second histograms corresponding to a plurality of pixels in the macropixel respectively based on the echoes of p detection scans detected by the pixel array, where p is an integer greater than 0; as well as Based on the plurality of second histograms, a distance and / or a reflectivity of the object is determined.

2. The method according to claim 1, characterized in that The method further includes: superimposing the plurality of second histograms with the first histogram respectively to generate a plurality of combined pixel histograms, and further determining the distance and / or reflectivity of the object based on the plurality of combined pixel histograms.

3. The method according to claim 2, characterized in that Each of the combined pixels includes a plurality of super pixels, each super pixel includes a third number of pixels, wherein the method further includes: In response to a signal intensity in a combined pixel histogram corresponding to a combined pixel in the macro pixel exceeding a second detection threshold, generating a plurality of third histograms corresponding to a plurality of super pixels in the combined pixel, respectively, based on echoes of q detection scans detected by the pixel array, where q is an integer greater than 0; and Based on the plurality of third histograms, a distance and / or a reflectivity of the object is determined.

4. The method according to claim 1, characterized in that Each of the combined pixels includes a plurality of super pixels, each super pixel includes a third number of pixels, wherein the method further includes: In response to the signal intensity in the second histogram corresponding to the combined pixel in the macro pixel exceeding a third detection threshold, based on the echoes of q detection scans detected by the pixel array, generate a plurality of third histograms corresponding to a plurality of super pixels in the combined pixel, respectively, where q is an integer greater than 0; and Based on the plurality of third histograms, a distance and / or a reflectivity of the object is determined.

5. The method according to claim 3 or 4, characterized in that The method also includes: respectively superimposing the multiple third histograms with the first histogram and the second histogram to generate multiple superpixel histograms, and further determining the distance and / or reflectivity of the object based on the multiple superpixel histograms.

6. The method according to claim 1, characterized in that The method further includes: determining an echo time according to the first histogram.

7. The method according to claim 6, characterized in that For the p detection scans, the multiple second histograms are generated in a time neighborhood of the echo moment.

8. The method according to claim 6, characterized in that During the p detection scans, the macro pixel is activated and data is collected for the macro pixel in the time neighborhood of the echo moment.

9. The method according to claim 1, characterized in that The time bins of the first histogram are characterized by a first width to represent echo intensities detected during a first flight time range, and the time bins of the second histogram are characterized by a second width different from the first width to represent echo intensities detected during a second flight time range different from the first flight time.

10. The method according to claim 9, characterized in that The first width is greater than the second width.

11. The method according to any one of claims 1, 2 and 5, characterized in that The method further comprises a denoising step, wherein the denoising step comprises removing noise floor values ​​in the first histogram, the combined pixel histogram and / or the superpixel histogram.

12. A laser radar, comprising: Transmitting unit; A pixel array including a plurality of macro-pixels, each macro-pixel including a plurality of composite pixels, wherein each macro-pixel includes a first number of pixels and each composite pixel includes a second number of pixels; A control unit configured as follows: The transmitting unit transmits laser pulses toward the field of view of the laser radar; Based on the echoes of o detection scans detected by the pixel array, generate a plurality of first histograms respectively corresponding to the plurality of macro pixels, wherein o is an integer greater than 0; In response to the signal intensity in the first histogram corresponding to the macropixel exceeding a first detection threshold, generating a plurality of second histograms corresponding to a plurality of pixels in the macropixel respectively based on the echoes of p detection scans detected by the pixel array, where p is an integer greater than 0; as well as Based on the plurality of second histograms, a distance and / or a reflectivity of the object is determined.

13. The laser radar according to claim 12, characterized in that: The control unit is further configured to: superimpose the plurality of second histograms with the first histogram respectively to generate a plurality of combined pixel histograms, and further determine the distance and / or reflectivity of the object based on the plurality of combined pixel histograms.

14. The laser radar according to claim 13, characterized in that: Each of the combined pixels includes a plurality of super pixels, each super pixel includes a third number of pixels, wherein the control unit is further configured to: In response to a signal intensity in a combined pixel histogram corresponding to a combined pixel in the macro pixel exceeding a second detection threshold, generating a plurality of third histograms corresponding to a plurality of super pixels in the combined pixel, respectively, based on echoes of q detection scans detected by the pixel array, where q is an integer greater than 0; as well as Based on the plurality of third histograms, a distance and / or a reflectivity of the object is determined.

15. The laser radar according to claim 12, characterized in that: Each of the combined pixels includes a plurality of super pixels, each super pixel includes a third number of pixels, wherein the control unit is further configured to: In response to a signal intensity in a second histogram corresponding to a combined pixel in the macro pixel exceeding a second detection threshold, generating a plurality of third histograms corresponding to a plurality of super pixels in the combined pixel, respectively, based on echoes of q detection scans detected by the pixel array, where q is an integer greater than 0; as well as Based on the plurality of third histograms, a distance and / or a reflectivity of the object is determined.

16. The laser radar according to claim 14 or 15, characterized in that: The control unit is also configured to: superimpose the multiple third histograms with the first histogram and the second histogram respectively to generate multiple superpixel histograms, and determine the distance and / or reflectivity of the object further based on the multiple superpixel histograms.

17. The laser radar according to claim 12, characterized in that: The control unit is further configured to determine an echo time according to the first histogram.

18. The laser radar according to claim 17, characterized in that: For the p detection scans, the multiple second histograms are generated in a time neighborhood of the echo moment.

19. The laser radar according to claim 18, characterized in that: The control unit is further configured to: during the p detection scans, activate the macro pixel and collect data for the macro pixel within a time neighborhood of the echo moment.

20. The laser radar according to claim 12, characterized in that: The time bins of the first histogram are characterized by a first width to represent echo intensities detected during a first time-of-flight range, and the time bins of the second histogram are characterized by a second width different from the first width to represent echo intensities detected during a second time-of-flight range different from the first time-of-flight range.

21. The laser radar according to claim 20, characterized in that The first width is greater than the second width.

22. The laser radar according to any one of claims 12, 13 and 16, characterized in that: The control unit is further configured to perform a denoising operation, wherein the denoising operation includes removing a noise floor value in the first histogram, the combined pixel histogram and / or the superpixel histogram.

23. The laser radar as claimed in claim 12, wherein the pixel array includes multiple levels of pixel blocks, wherein a pixel block of a previous level includes multiple pixel blocks of a subsequent level, wherein pixel blocks of different levels have different numbers of pixels, wherein the field of view of the laser radar includes a first area and a second area, The pixel area corresponding to the first area in the pixel array has fewer levels of pixel blocks, while the pixel area corresponding to the second area in the pixel array has more levels of pixel blocks.

24. A terminal device, comprising the laser radar as described in any one of claims 12-23.

25. A computer-readable storage medium storing instructions, wherein the instructions are executed by a processor to implement the method according to any one of claims 1 to 11.

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