Method, device and computer program product for correcting lidar data

Abstract

The present invention discloses a method and a device for correcting lidar data, wherein the method includes: recording a plurality of signal characterization values when the real-time signal intensity values of echo signals respectively reach a plurality of target signal intensity values; and obtaining a data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the plurality of target signal intensity values and the plurality of signal characterization values. Compared with the prior art, the solution of the present invention has advantages such as a simple data correction process and high accuracy of corrected data.

Description

Technical Field

[0001] The present invention generally relates to the field of lidar. More specifically, the present invention relates to a method for correcting lidar data, a lidar device, a device for lidar, and a computer program product. Background Art

[0002] Lidar is a radar system that emits laser signals to detect characteristic quantities such as the position and speed of a target object. Specifically, lidar emits a laser detection signal towards the target object, and then compares the received echo signal reflected from the target object with the transmitted signal. After further processing, relevant information of the target object can be obtained. For example, information such as the distance, speed, and azimuth angle of the target object can be obtained, so that the target object can be detected, tracked, and identified. In lidar technology, the detection sensitivity and accuracy of the lidar for the echo signal determine the performance of the lidar.

[0003] The echo signal of lidar usually has a Gaussian-like waveform distribution. The time for the waveform front to reach the peak point (i.e., the front timing value) is proportional to the energy of the echo signal. Therefore, it is possible that at the same distance, when using lidar to measure target objects with different reflectivities, the front timing values of the obtained echo signals are different, resulting in differences in the ranging values of lidar for target objects with different reflectivities at the same distance. Based on the above principle, in the process of lidar data processing, it is usually necessary to correct the front timing values of echo signals under different energies (for example, which can be represented by the real-time signal intensity).

[0004] Currently, the method for lidar to obtain the aforementioned data correction relationship is usually as follows: at a fixed distance, by using an occluder, such as a diaphragm, to occlude the transmitting field of view or receiving field of view of the lidar, so as to change the transmitting or receiving energy of the lidar, and thus obtain the data correction values of the front timing values under different energies, that is, the data correction relationship. Since the detection sensitivity and accuracy of the echo signal determine the performance of the lidar, the higher the precision of the data correction relationship, the corresponding improvement in the ranging accuracy of the lidar will be obtained.

[0005] In the above-mentioned conventional occlusion-based data correction method, due to the size difference between the light spot and the occluder, it is not easy to ensure the uniform change of the echo signal energy during the movement of the occluder. In actual operation, the movement of the occluder may cause a sudden change in the echo signal energy, and the energy change of the echo signal obtained by moving the occluder is not precise enough, resulting in an inaccurate data correction relationship of the obtained front timing value, and ultimately causing a ranging error for the target object.

[0006] In addition, when using the above-mentioned data correction method based on occlusion, it is necessary to traverse all the energy values of the radar echo signals within the range from the minimum to the maximum during the occlusion process. However, due to the mutual interference between multiple lines, there are often blind spots in the detection of lidar (such as the area from 0 to 4 meters), so the requirement of traversing all energy values cannot be met. In view of this situation, the data correction method based on occlusion has very high requirements for the correction environment. Usually, it needs to be carried out in a sufficiently open space, and a strong reflection target with a sufficiently large area is required to be placed. Further, this data correction method based on occlusion requires the cooperation of the upper and lower computers to obtain echo signals with different energies by adjusting the displacement of the occluder through closed-loop control, which makes the correction process too cumbersome. Summary of the Invention

[0007] To at least solve one or more of the above problems in the background art, the present invention provides a solution for lidar. The solution of the present invention records multiple signal characterization values, and constructs a data correction relationship between the echo signal and the signal characterization values based on the multiple signal characterization values and multiple preset target signal intensity values, so as to obtain a data correction relationship with high accuracy. In some embodiments, the solution of the present invention also sets an intensity threshold for the echo signal intensity, and obtains a signal characterization reference value based on the intensity threshold, so that the data correction relationship can be obtained by using the multiple differences between the multiple signal characterization values and the signal characterization reference value.

[0008] Specifically, in one aspect, the present invention discloses a method for lidar. The method includes: recording multiple signal characterization values when the real-time signal intensity values of the echo signal reach multiple target signal intensity values respectively; and obtaining a data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the multiple target signal intensity values and the multiple signal characterization values.

[0009] In one embodiment, the method further includes determining the multiple target signal intensity values according to the signal intensity threshold and the number of records of the echo signal.

[0010] In yet another embodiment, the multiple target signal intensity values include the signal intensity threshold of the echo signal, and the multiple signal characterization values include the signal characterization value when the real-time signal intensity value of the echo signal reaches the signal intensity threshold.

[0011] In another embodiment, the method further includes: recording the signal characterization value when the real-time signal intensity value of the echo signal reaches the intensity threshold as the signal characterization reference value of the multiple signal characterization values; and obtaining the data correction relationship according to the multiple differences between the multiple signal characterization values and the signal characterization reference value.

[0012] In one embodiment, in each recording, the method includes: adjusting the positive pulse width of the laser charging pulse so that the real-time signal intensity value of the echo signal reaches a corresponding target signal intensity value.

[0013] In another embodiment, in each recording, the method includes repeatedly performing the following steps until the real-time signal intensity value is equal to a corresponding target signal intensity value: adjusting the positive pulse width of the laser charging pulse to emit a laser signal; receiving the echo signal for the laser signal and measuring the real-time signal intensity value; determining whether the real-time signal intensity value is equal to a corresponding target signal intensity value; and in response to the real-time signal intensity value not being equal to a corresponding target signal intensity value, repeating the adjustment.

[0014] In yet another embodiment, obtaining the data correction relationship according to the multiple differences between the multiple signal characterization values and the signal characterization reference value includes: fitting the multiple target signal intensity values with the corresponding multiple differences to obtain a relationship curve reflecting the relationship between both the target signal intensity value and the difference.

[0015] In another aspect, the present invention also discloses a lidar device. The device includes: a transmitter configured to emit a laser signal to a target; a receiver configured to receive an echo signal reflected from the target; and a processor configured to execute the foregoing method.

[0016] In yet another aspect, the present invention also discloses a device for lidar. The device includes: at least one processor; and a memory storing program instructions that, when executed by the at least one processor, cause the device to perform: recording multiple signal characterization values when the real-time signal intensity values of the echo signal respectively reach multiple target signal intensity values; and obtaining a data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the multiple target signal intensity values and the multiple signal characterization values.

[0017] In another aspect, the present invention also discloses a computer program product. The computer program product includes computer program instructions for lidar that, when executed by one or more processors, cause it to implement the foregoing method.

[0018] Through the above general description of the technical solution of the present invention, those skilled in the art can understand that the technical solution of the present invention records multiple times to obtain a curve of the corresponding relationship between the signal characterization value of the echo signal (or the difference between the signal characterization value and the signal characterization reference value) and the target signal intensity value, and then uses this curve to correct the signal characterization value of the real-time echo signal of the lidar. The technical solution of the present invention solves the problems of overly complex data correction for signal characterization values and low accuracy in the prior art, thereby achieving the purpose of reducing measurement errors when using the radar device of the technical solution of the present invention to measure a target object. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features, and advantages of the exemplary embodiments of the present invention will become readily understood. In the drawings, several embodiments of the present invention are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0020] Figure 1 is a flowchart showing a method according to an embodiment of the present invention;

[0021] Figure 2 is a detailed flowchart showing a method according to an embodiment of the present invention;

[0022] Figure 3 is a relationship curve showing the target signal intensity value and the difference according to an embodiment of the present invention; and

[0023] Figure 4 is a block diagram showing the composition principle of a lidar device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Figure 1 is a flowchart showing Method 100 according to an embodiment of the present invention. As Figure 1As shown, at step S101, multiple signal characterization values are recorded when the real-time signal intensity values of the echo signal respectively reach multiple target signal intensity values. In one embodiment, the multiple target signal intensity values here can be determined according to the signal intensity threshold of the echo signal and the number of recordings. In another embodiment, the foregoing multiple target signal intensity values may include the signal intensity threshold of the echo signal (this threshold can be set manually or by the manufacturer, for example). Correspondingly, the foregoing multiple signal characterization values may include the signal characterization values measured (or recorded) when the real-time signal intensity value of the echo signal reaches the signal intensity threshold. In some implementation scenarios, the signal intensity threshold and / or the maximum number of recordings here can also be set according to the actual situation of the lidar device and the need to correct the signal characterization values. According to different implementation scenarios, the signal characterization value of the present invention may include the leading edge timing value, trailing edge timing value, signal peak timing value of the echo signal, or any other characterization value that can reflect the attributes of the echo signal.

[0026] Next, at step S102, a data correction relationship between the signal intensity value and the signal characterization value of the echo signal is obtained based on the multiple target signal intensity values and the multiple signal characterization values. In one embodiment, when considering that the target signal intensity value includes the signal intensity threshold described above, the signal characterization value corresponding to the signal intensity threshold can be set as the signal characterization reference value. Based on this, the difference operation can be performed on the corresponding signal characterization values of other target signal intensity values and this reference value, so as to obtain the differences of the multiple signal characterization values. In this way, the above data correction relationship of the present invention can be expressed by the one-to-one correspondence between the differences of the multiple signal characterization values and the multiple target signal intensity values.

[0027] To achieve accurate recording, that is, to record when the real-time signal intensity value of the echo signal reaches (or equals) the corresponding target signal intensity value, the solution of the present invention proposes to change the real-time signal intensity value of the echo signal by repeatedly adjusting the transmission power of the lidar (for example, by adjusting the positive pulse width of the laser charging pulse) until it equals the predetermined target signal intensity value. It can be understood that when the real-time intensity value equals the above-mentioned signal intensity threshold, the signal characterization value at this time can be recorded as the signal characterization reference value described above. Regarding the recording operation, the method of the present invention can record the measured signal characterization value and / or its difference from the signal characterization reference value each time starting from the first recording. This recording process continues until the number of recordings reaches the maximum number of recordings and then stops.

[0028] Regarding the above-mentioned target signal strength value, in one embodiment, it can be determined based on the signal strength threshold, the maximum number of recordings, and the number value of the current recording. After determining the target signal strength value corresponding to the current recording, as described above, the transmission power of the lidar can be adjusted in a closed-loop manner repeatedly, so that the real-time signal strength value of the echo signal continuously approaches the target signal strength value, and when the two are equal, the operation of recording the signal characterization value of this time is executed.

[0029] In order to enable the real-time signal strength value to reach the target signal strength value, the real-time signal strength value of the echo signal can be compared with the target signal strength value, and the transmission power of the lidar is adjusted in a closed-loop manner based on the comparison, thereby continuously adjusting the real-time signal strength value to meet the recording conditions. Specifically, when the measured real-time signal strength value of the echo signal is not equal to (i.e., less than or greater than) the target signal strength value, the transmission power of the lidar is adjusted. According to different implementation scenarios, the adjustment of the transmission power in the present invention can be carried out in different ways here. For example, the foregoing transmission power can be adjusted by any suitable means such as adjusting the luminous intensity (such as adjusting the positive pulse width of the laser charging pulse), adjusting the charging voltage, and / or changing the circuit parameters of the laser drive.

[0030] The above adjustment process may last for multiple times in some scenarios and stop until the real-time signal strength value is equal to the target signal strength value. When the two are equal, the signal characterization value of the obtained echo signal can be recorded at this time. As described above, the obtained signal characterization value can also be subtracted from the foregoing signal characterization reference value to obtain the difference value of the signal characterization value of this recording. Based on this, the corresponding relationship between the target signal strength value and the corresponding signal characterization value can also be obtained through this recording.

[0031] In one embodiment, through a predetermined number of recordings and the above subtraction operation, the method of the present invention can obtain the correction relationship data between the target signal strength values of all recording times and their corresponding differences. It can be understood that the correction relationship data can be in the form of multiple discrete values. In order to clearly express the data correction "relationship", the method of the present invention can perform a fitting operation on the above-obtained discrete values, so as to fit the discrete data into a graph reflecting the continuous corresponding relationship. In some application scenarios, the continuous corresponding relationship can be expressed in the form of a continuous function, for example. In some application scenarios, the continuous corresponding relationship can be shown by a curve (such as Figure 3 shown in). After obtaining the above data correction relationship, the signal characterization values corresponding to the echo signals of all real-time signal strength values of the lidar can be corrected through this data correction relationship.

[0032] Figure 2is a detailed flowchart showing method 200 according to an embodiment of the present invention. It can be understood that Figure 2 the shown method 200 is Figure 1 a specific implementation of the shown method 100. Therefore, in combination with Figure 1 the description of method 100 also applies to the description of method 200, and Figure 2 the shown method 200 is merely exemplary and illustrative, and it cannot be used to limit the solution of the present invention.

[0033] As Figure 2 shown, at step S201, the process of setting the maximum threshold of the echo signal intensity (i.e., the aforementioned signal intensity threshold) and the maximum number of records, where the signal intensity threshold and the maximum number of records can be set according to the actual situation of the lidar device and the need to correct the signal characterization value of the echo signal. Then, at step S202, the signal characterization reference value of the echo signal is calculated. Specifically, let the target signal intensity value be equal to the signal intensity threshold of the echo signal. On this basis, by adjusting the transmission power of the lidar in a closed loop (for example, by adjusting the positive pulse width of the laser charging pulse), the real-time signal intensity value of the echo signal is made equal to the signal intensity threshold, and the signal characterization value of the echo signal at this time is used as the signal characterization reference value.

[0034] Subsequently, at step S203, the number of records is cleared (or the number of records is initialized), so as to eliminate the previous records and make the records of this round start from the first time until the maximum number of records is reached. After that, at step S204, the target intensity value of the current record is calculated. When the current record is the first record, its target intensity value can be determined according to the signal intensity threshold of the echo signal and the maximum number of records. For example, assume the signal intensity threshold is V max , and the maximum number of records is N. Then, on the premise of obtaining uniformly discrete signal characterization value correction data, the target intensity value of the first record is equal to 1×V max / N. Similarly, the target intensity value of the nth record is equal to n×V max / N. In addition, it can be understood that the calculation operation in step S204 can also be executed after step S201. Further, all the target signal intensity values corresponding to the records can be pre-calculated in step S204, thereby avoiding the need to calculate the aforementioned target signal intensity value separately during each record.

[0035] Next, perform step S205 and step S206. At step S205, determine whether the real-time signal intensity value of the echo signal is equal to the target signal intensity value. If, after judgment, the real-time signal intensity value of the echo signal is not equal to the target signal intensity value (i.e., "No" in the figure), then at step S206, adjust the transmission power of the lidar. For example, the transmission power of the lidar can be changed by adjusting the positive pulse width of the laser charging pulse, so as to adjust the real-time signal intensity value. Specifically, the process of adjusting the transmission power of the lidar is a closed-loop process, that is, when the real-time signal intensity value of the echo signal is not equal to the target signal intensity value, the above judgment and adjustment processes will be repeatedly executed until the real-time signal intensity value of the echo signal is equal to the corresponding target signal intensity value.

[0036] When it is determined at step S205 that the real-time signal intensity value of the echo signal is equal to the target signal intensity value (i.e., "Yes" in the figure), the process proceeds to step S207. At this step, stop adjusting the transmission power of the lidar. Subsequently, at steps S208 and S209, calculate the difference between the signal characterization values of the echo signal recorded this time, and record the corresponding relationship between the target intensity value and the signal characterization value this time. Specifically, the difference operation can be performed between the signal characterization value of the echo signal at this time and the signal characterization reference value obtained in the above step S202, so as to obtain the difference between the signal characterization values recorded this time. Further, establish a one-to-one correspondence between the target intensity value recorded this time and the difference between the signal characterization values recorded this time, so as to be used as the data recorded this time.

[0037] Next, the process proceeds to step S210. At this step, determine whether the number of records is equal to the maximum number of records. If the number of records this time is less than the maximum number of records (i.e., "No" in the figure), then at step S211, perform an operation of adding 1 to the number of records. Subsequently, the process jumps back to execute step S204, that is, start the next recording process, which will not be elaborated here. When it is determined at step S210 that the number of records this time is equal to the maximum number of records (i.e., "Yes" in the figure), then at step S212, fit the corresponding relationship between the target signal intensity values and the signal characterization values recorded for all records to obtain a graphical representation such as a relationship curve. According to different scenarios, the relationship curve can satisfy a certain linear function and / or non-linear function, and the fitted curve can be a regular curve or a free curve, and the present invention does not make any restrictions in this regard.

[0038] Figure 3 FIG. 300 is a relationship curve showing the difference between the target signal intensity value and the signal characterization value according to an embodiment of the present invention. It can be understood that Figure 3 The shown curve 300 can be Figure 1 of the method 100 and / or Figure 2Further, the curve 300 is only exemplary and illustrative, and does not limit the data correction relationship obtained by the method 100 and the method 200 in any sense.

[0039] like Figure 3 The curve 300 shown in FIG. 3 has a horizontal coordinate of the difference ΔTn of the signal characterization value and a vertical coordinate of the target signal strength value V. In this example, the number of recordings can be set to 10 according to the correction requirements, and 10 discrete data are obtained after 10 recording processes, which corresponds to Figure 3 For example, the data recorded for the sixth time corresponds to Figure 3 Points in (ΔT 6 , V 6 ), the data recorded for the Nth time corresponds to Figure 3 Points in (ΔT N , V max ), where V max is the signal strength threshold of the set echo signal. Optionally, the 10 discrete points may be evenly distributed on the abscissa, so as to obtain a correction relationship of a uniform signal characterization value.

[0040] Furthermore, by performing a fitting operation on these 10 discrete points, the 10 discrete points are connected to obtain Figure 3 After obtaining the continuous curve, the max The signal characterization value of the echo signal of any intensity value within the energy range is corrected. Taking the signal characterization value as the leading edge timing value as an example, when the real-time signal strength value of the echo signal is v, by querying Figure 3 A continuous curve is obtained to obtain the corresponding difference Δt. Further, the current leading edge timing value of the echo signal is added with the difference Δt to obtain the corrected leading edge timing value.

[0041] Figure 4 4 is a block diagram showing the composition principle of the laser radar device 400 according to an embodiment of the present invention. In order to better understand the principle and function of the laser radar device of the present invention, Figure 4 The application environment including the target object 440 is also depicted, wherein the target object receives the laser signal (i.e. Figure 4 The emission signal in the laser beam is Figure 4 The echo signal in the laser radar device 400 is reflected back to the laser radar device 400.

[0042] like Figure 4As shown, the lidar device may include a transmitter 410, a receiver 420, and a processor 430. Further, the transmitter 410 may include a transmitting unit 411 and a transmitting antenna 412. In one embodiment, the transmitting unit may generate modulated pulsed laser and transmit it to the target via the transmitting antenna. Correspondingly, the receiver 420 may include a receiving unit 421 and a receiving antenna 422, which are configured to receive the echo signal reflected back from the target. The processor of the lidar device of the present invention may be composed of a chip or module such as a CPU with functions of analysis, judgment, and calculation, and is configured to execute the foregoing method 100 and / or method 200 to correct the signal characterization value of the echo signal reflected by the target.

[0043] In yet another aspect, the present invention also discloses a device for lidar. The device may include at least one processor and a memory, where the memory stores program instructions, and when the program instructions are executed by the at least one processor, the device is caused to perform the following operations: (1) Record a plurality of signal characterization values when the real-time signal intensity values of the echo signal reach a plurality of target signal intensity values respectively. (2) Obtain the data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the plurality of target signal intensity values and the plurality of signal characterization values. According to different application scenarios, the device herein of the present invention may be connected to the lidar device in various ways and receive various data of the present invention from the lidar device, such as including each real-time signal intensity value of the echo signal, so as to obtain the data correction relationship of the present invention.

[0044] In another aspect, the present invention also discloses a computer program product. The computer program product may include computer program instructions for lidar, and when the computer program instructions are executed by one or more processors, it causes the implementation of the foregoing method 100 and / or method 200.

[0045] The above computer program product may be any suitable magnetic storage medium or magneto-optical storage medium, such as, resistive random access memory (RRAM), dynamic random access memory (DRAM), static random-access memory (SRAM), enhanced dynamic random access memory (EDRAM), high-bandwidth memory (HBM), hybrid memory cube (HMC), etc., or any other medium that can be used to store the required information and can be accessed by an application program, a module, or both. Any such computer storage medium may be part of the device or accessible or connectable to the device. Any application or module described in the present invention may be implemented using computer-readable / executable instructions that can be stored or otherwise held by such a computer-readable medium.

[0046] It should be understood that the terms "first", "second", "third", "fourth", etc. in the claims, the description and the drawings of the present invention may be used to distinguish different objects, rather than to describe a specific order. The terms "comprising" and "including" used in the description and claims of the present invention indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0047] It should also be understood that the terms used in the specification of the present invention disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present invention disclosure. As used in the specification and claims of the present invention disclosure, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms. It should be further understood that the term "and / or" used in the specification and claims of the present invention disclosure refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0048] Although the embodiments of the present invention are as above, the above content is only an example used to facilitate the understanding of the present invention and is not intended to limit the scope and application scenarios of the present invention. Any person skilled in the art within the technical field described in the present invention may make any modifications and changes in the form of implementation and details without departing from the spirit and scope disclosed by the present invention. However, the scope of patent protection of the present invention shall still be subject to the scope defined by the appended claims.

Claims

1. A method for correcting lidar data, comprising: recording a plurality of signal characterization values when the real-time signal intensity values of the echo signals respectively reach a plurality of target signal intensity values; and obtaining a data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the plurality of target signal intensity values and the plurality of signal characterization values; recording the signal characterization value when the real-time signal intensity value of the echo signal reaches an intensity threshold as the signal characterization reference value of the plurality of signal characterization values; wherein the correction relationship is expressed by a one-to-one correspondence between a plurality of differences between the plurality of signal characterization values and the signal characterization reference value and the plurality of target signal intensity values.

2. The correction method according to claim 1, further comprising: determining the plurality of target signal intensity values according to the signal intensity threshold and the number of records of the echo signal.

3. The correction method according to claim 1, wherein the plurality of target signal intensity values include the signal intensity threshold of the echo signal, and the plurality of signal characterization values include the signal characterization value when the real-time signal intensity value of the echo signal reaches the signal intensity threshold.

4. The correction method according to claim 1, wherein in each record, the method comprises: adjusting the positive pulse width of the laser charging pulse so that the real-time signal intensity value of the echo signal reaches a corresponding target signal intensity value.

5. The correction method according to claim 1, wherein in each record, the method comprises repeatedly performing the following steps until the real-time signal intensity value is equal to a corresponding target signal intensity value: adjusting the transmission power to transmit a laser signal; receiving the echo signal for the laser signal and measuring the real-time signal intensity value; judging whether the real-time signal intensity value is equal to a corresponding target signal intensity value; and responding to the real-time signal intensity value not being equal to a corresponding target signal intensity value, repeating the adjustment.

6. The correction method according to claim 5, wherein adjusting the transmission power includes adjusting the transmission power in one or more of the following ways: adjusting the positive pulse width of the laser charging pulse; adjusting the charging voltage; and changing the circuit parameters of the laser drive.

7. The correction method according to claim 1, wherein obtaining the data correction relationship according to the plurality of differences between the plurality of signal characterization values and the signal characterization reference value comprises: fitting the plurality of target signal intensity values with the corresponding plurality of differences to obtain a relationship curve reflecting the relationship between the target signal intensity value and the difference.

8. A lidar device, comprising: a transmitter configured to transmit a laser signal to a target; a receiver configured to receive an echo signal reflected from the target; and a processor configured to execute the method according to any one of claims 1-7.

9. A device for lidar, comprising: at least one processor; and a memory storing program instructions, which when executed by the at least one processor cause the device to execute: Record multiple signal characterization values when the real-time signal intensity values of the echo signals respectively reach multiple target signal intensity values; And Obtain a data correction relationship between the signal intensity value and the signal characterization value of the echo signal based on the multiple target signal intensity values and the multiple signal characterization values.

10. A computer program product, comprising computer program instructions for correcting lidar data, which, when executed by one or more processors, cause it to implement the method according to any one of claims 1-7.

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