Pulse laser ranging method and system based on reverse overshoot suppression

Abstract

The invention provides a pulse laser ranging method and system based on reverse overshoot suppression, and relates to the technical field of laser ranging, and the method comprises the steps: obtaining a to-be-detected target; laser pulses are emitted to a to-be-detected target through a laser; sampling echo signals reflected from the to-be-detected target for multiple times; performing in-phase combination on the echo signals sampled for multiple times to obtain stable echo signals; performing reverse overshoot removal processing on the stable echo signal to obtain an effective echo signal; performing energy detection analysis on the effective echo signal, and calculating the accurate arrival time of the effective echo signal; and determining the actual distance between the to-be-detected target and the laser based on the accurate arrival time. According to the invention, in-phase combination and overshoot removal processing are combined, accurate and effective echo signals are obtained, the problem of small signal loss or false detection caused by reverse overshoot in the prior art is avoided, and the distance measurement precision is remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser ranging technology, in particular to a pulse laser ranging method and system based on reverse overshoot suppression. BACKGROUND

[0002] Pulse laser ranging technology is widely used in unmanned aerial vehicles, laser ranging telescopes, and autonomous driving due to its small size, long range, and fast response speed. Laser range finders emit pulsed laser and receive the echo signal reflected by the object, and calculate the distance between the object and the measuring instrument according to the speed of light and the signal propagation time. With the continuous development of laser ranging technology, the accuracy and reliability of the ranging are increasingly required. Especially when measuring long-distance objects, the laser echo signal may be affected by various interference factors, affecting the accuracy of the measurement results. How to effectively remove the interference signal, especially the reverse overshoot interference signal, has become one of the key technologies to improve the accuracy of the range finder.

[0003] Currently, the technology commonly used by pulse laser range finders is to collect signals through high-speed ADC after receiving echo signals, and process them combined with digital signal processing (DSP) algorithms. These technologies can enhance signal quality through multiple sampling, signal superposition, and other means. However, due to the characteristics of laser emission pulses, the transmitted signal will produce a reverse overshoot at the receiving end, which has a great impact on the detection of echo signals, especially on low reflectivity targets. Existing technologies usually suppress reverse overshoot through hardware means or process it through signal filtering, but this often cannot completely eliminate interference, especially when measuring at a long distance, the interference signal may still affect the correct detection of the echo signal, and the measurement accuracy cannot be guaranteed. SUMMARY

[0004] In view of the above deficiencies of the prior art, the purpose of the embodiments of the present application is to provide a pulse laser ranging method based on reverse overshoot suppression, which can solve the technical problem that the prior art usually suppresses reverse overshoot through hardware means or processes it through signal filtering, but this often cannot completely eliminate interference, especially when measuring at a long distance, the interference signal may still affect the correct detection of the echo signal, and the measurement accuracy cannot be guaranteed.

[0005] The first aspect of the embodiments of the present application proposes a pulse laser ranging method based on reverse overshoot suppression, comprising: S1: acquiring a target to be detected; S2: emitting a laser pulse to the target to be detected through a laser; S3: sampling the echo signal reflected from the target to be detected multiple times; S4: co-phasing the multiple sampled echo signals to obtain a stable echo signal; S5: performing a reverse overshoot removal processing on the stable echo signal to obtain an effective echo signal; S6: performing an energy detection analysis on the effective echo signal to calculate an accurate arrival time of the effective echo signal; S7: determining an actual distance between the to-be-detected target and the laser device based on the accurate arrival time.

[0006] In a second aspect, the embodiment of the present application provides a pulse laser ranging system based on reverse overshoot suppression, comprising a processor and a memory. The memory stores programs or instructions executable on the processor, and the programs or instructions are executed by the processor to implement the steps of the pulse laser ranging method based on reverse overshoot suppression as described in the first aspect.

[0007] In a third aspect, the embodiment of the present application provides a readable storage medium, and the readable storage medium stores programs or instructions, and the programs or instructions are executed by a processor to implement the steps of the pulse laser ranging method based on reverse overshoot suppression as described in the first aspect.

[0008] The technical scheme provided by the embodiment of the present application has at least the following beneficial effects: In the embodiment of the present application, the stability of the echo signal is enhanced by sampling the echo signal multiple times and performing in-phase combination. Meanwhile, the influence of the interference signal is effectively eliminated by using the overshoot removal processing technology for the generated reverse overshoot interference. By combining the in-phase combination and the overshoot removal processing, an accurate effective echo signal is obtained, the problem of small signal loss or false detection caused by reverse overshoot in the prior art is avoided, and the ranging accuracy is significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings are only for the purpose of illustrating specific embodiments and are not considered as limiting the present application. In the entire drawings, the same reference signs represent the same components. Obviously, the accompanying drawings described below are only some embodiments described in the embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0010] Figure 1 is a flowchart of a pulse laser ranging method based on reverse overshoot suppression provided by the embodiment of the present application; Figure 2 is a flowchart of a signal energy detection analysis provided by the embodiment of the present application; Figure 3 is an original signal waveform diagram of reverse overshoot removal provided by the embodiment of the present application; Figure 4Fig. 1 is a structural schematic diagram of a pulse laser ranging system based on reverse overshoot suppression provided by an embodiment of the present application. DETAILED DESCRIPTION

[0011] In order for those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. It should be understood that these descriptions are only exemplary and are not used to limit the scope of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work should belong to the scope of protection of the present application.

[0012] The pulse laser ranging method based on reverse overshoot suppression provided by the embodiments of the present application will be described in detail below in conjunction with the drawings, specific embodiments and application scenarios.

[0013] Reference is made to the accompanying drawings Figure 1 Fig. 1 is a structural schematic diagram of a pulse laser ranging method based on reverse overshoot suppression provided by an embodiment of the present application.

[0014] The pulse laser ranging method based on reverse overshoot suppression provided by the embodiments of the present application can include the following steps: S1: Obtain a target to be detected.

[0015] S2: Emit a laser pulse to the target to be detected by a laser.

[0016] The laser pulse is a high-energy light beam emitted in a short time. It is different from a continuous laser beam. The pulse laser has a clear start and end time in time, and usually emits a light pulse with large energy at a very short time interval (such as nanosecond, picosecond or femtosecond level).

[0017] It should be noted that the system will send different pulse times according to different distances, and the bottom noise will be eliminated and the echo pulse will be strengthened by superposition and averaging. The number of times in the present embodiment is 200.

[0018] Specifically, the laser emits a laser pulse and lasts for a very short period of time (100 ns level). The laser used in the present embodiment is not limited to the type and power of the pulse laser, and a pulse laser with a power of 5w to 100w can be used, which can withstand a single pulse width of 200ns or less. When the emission logic device controls the emission circuit to emit a laser pulse, a weak echo signal will be obtained after reflection by the object.

[0019] S3: Sample the echo signal reflected from the target to be detected multiple times.

[0020] It should be noted that the purpose of multiple samplings is to eliminate noise and enhance the target echo signal by superimposing and averaging the samples.

[0021] Specifically, the receiving end samples the returned signal using a high-speed ADC (60MHz-200MHz): based on the sampling of the high-speed ADC, the acquired signal can be sent to the logic calculation and control module for storage.

[0022] An ADC (Analog-to-Digital Converter) is an electronic device or circuit that converts analog signals into digital signals. It is an indispensable component of modern electronic devices and is widely used in communication, audio processing, image processing, sensors, measurement systems, and many other fields. The basic function of an ADC is to convert continuous analog signals (such as temperature, pressure, and voltage) into discrete digital signals so that computers or digital processing systems can process and analyze them.

[0023] In one possible implementation, the echo signal acquired in a single acquisition is specifically:

[0024] in, y n Indicates the first n The echo signal acquired in this second acquisition Indicates the first n The Mth sampling point of the echo signal M Indicates the sampling length of the echo signal. N This indicates the total number of samples.

[0025] In this embodiment of the invention, by sampling the echo signal multiple times, the system can acquire more detailed signal information. Each acquired echo signal may be affected by noise or interference; however, by sampling and storing these signals multiple times, noise can be effectively suppressed, ensuring that subsequent processing can more accurately extract the valid echo signal. Simultaneously, since the intensity of the echo signal may be very weak, especially during long-distance measurements, multiple sampling can obtain multiple echo data points, thereby increasing the stability of the echo signal. This reduces the impact of occasional signal fluctuations or short-term noise, making the acquired data more stable.

[0026] S4: Combine the echo signals sampled multiple times in phase to obtain a stable echo signal.

[0027] Among them, coherent averaging (Coherent Averaging or Coherent Addition) is a signal processing technique used to improve the quality and reliability of signals by combining signals in multiple samplings or multiple measurements. This method is especially suitable for obtaining weak signals in a noisy environment, which can effectively enhance the target signal while suppressing interference and noise. The core idea is to combine signals with the same phase to obtain a higher signal-to-noise ratio.

[0028] Optionally, after N =200 or more times of merging, a stable signal is obtained.

[0029] In one possible implementation, S4 specifically includes: S401: Superimpose and average the echo signals collected each time at the same time point to obtain the average signal at each time point:

[0030] Among them, represents the average signal at the m -1th time point, represents the echo signal at the N -1th time point collected m -1th time.

[0031] In the embodiments of the present application, by superimposing and averaging multiple signals, the strength of the signal is enhanced, while the strength of the noise is reduced. With the increase of the number of mergers (for example, 200 or more times), the signal-to-noise ratio (SNR) will continue to improve, which makes the final echo signal clearer and more stable, which helps subsequent signal processing and analysis.

[0032] S402: Arrange the average signals at each time point in time point order to obtain a stable echo signal:

[0033] Among them, represents the stable echo signal, represents the average signal at the M -1th time point.

[0034] In the embodiments of the present application, by arranging the time points in order, all the average signals after coherent merging will be continuous and stable. This makes the signal sequence smoother, reducing the instantaneous fluctuations caused by noise or random interference. The smoothness and stability of the signal are improved, avoiding errors or fluctuations that may exist in the single sampling process, thereby enhancing the reliability of the overall signal.

[0035] It should be noted that, since the far distance echo signal detection needs to be performed, the laser emission voltage is adjusted to the highest gear, and the receiving APD amplification is adjusted to the maximum, so as to perform centroid detection on the far distance small signal. Since there is self-interference of the transmitted signal at a short distance, a large reverse overshoot interference signal will be generated at the receiving end. Therefore, through the function of removing the reverse overshoot, the signal can be easily detected in the base noise.

[0036] Among them, the centroid detection (Centroid Detection) is a signal processing method for accurately determining the center position of the laser spot, and the core purpose is to calculate the "center of gravity" position of the spot by analyzing the intensity distribution of the received signal, so as to improve the ranging accuracy.

[0037] Among them, the base noise (Base Noise) refers to the inherent noise level introduced by the system itself and the environment when the laser ranging system does not receive the effective laser signal reflected by the target (or the useful signal is zero).

[0038] S5: removing the reverse overshoot of the stable echo signal to obtain the effective echo signal.

[0039] Among them, the reverse overshoot removal (Reverse Overshoot Removal) is a signal processing technology, which is usually used in laser ranging, radar, sensor and other applications, especially in pulsed laser ranging systems, and the purpose is to eliminate the interference signal generated by the laser pulse transmission, which is usually manifested as reverse overshoot. This reverse overshoot may affect the accurate detection of the target signal, so the removal of the reverse overshoot is a key step to improve the accuracy of the system.

[0040] In one possible implementation, S5 specifically includes: S501: performing weighted average processing on the stable echo signal using a smoothing window to obtain a smoothed signal.

[0041] S502: subtracting the smoothed signal from the stable echo signal to remove the reverse overshoot interference generated when the laser emits to obtain the effective echo signal.

[0042] It should be noted that the core of the whole step is to estimate and remove the reverse overshoot interference by performing weighted average on the current signal and its surrounding signals.

[0043] In one possible implementation, S502 specifically includes: Subtract the smoothed signal from the stable echo signal to remove the reverse overshoot interference generated when the laser emits to obtain the effective echo signal through the following formula:

[0044] Among them, represents an effective echo signal, represents the average value of the stable echo signal at the n th time point, represents the stable echo signal value at the n + m th time point, m represents the index of the time point.

[0045] In the embodiments of the present application, a kind of noise or unnecessary peak value is often formed in the received echo signal, and this overshoot signal often interferes with the accurate detection of target signal. By subtracting the smooth signal from the stable echo signal, the unnecessary interference can be effectively removed, thereby retaining the actual target signal. At the same time, due to the removal of the reverse overshoot, the system is not easy to cause measurement error due to the false identification of interference signals. For example, the reverse overshoot can cause the system to mistakenly believe that there is an additional echo signal, and after removing these interferences, the system can accurately identify the true echo signal and reduce the possibility of misjudgment.

[0046] Referring to the accompanying drawings of the specification, Figure 2 , a flowchart of a signal energy detection analysis provided by an embodiment of the present application is shown.

[0047] S6: performing energy detection analysis on the effective echo signal to calculate the accurate arrival time of the effective echo signal.

[0048] Energy detection analysis is a technique commonly used in signal processing and communication, especially in wireless communication, radar, laser ranging, sonar and other applications that need to detect the presence or absence of signals. Its main purpose is to analyze the energy of the signal to determine the strength, existence and other characteristics of the signal. Energy detection analysis is usually used to identify the presence of a signal or to determine whether the signal exceeds a certain threshold, helping the system to effectively extract useful information in a noisy environment.

[0049] In one possible implementation, S6 specifically includes: S601: segmenting the effective echo signal using a sliding window method.

[0050] In the embodiments of the present application, the sliding window method divides the signal into small segments for processing, which can concentrate on processing each segment of the signal and avoid errors caused by large fluctuations when processing the entire signal. This is particularly suitable for environments with strong noise and interference, and segmented processing can more accurately identify effective signals.

[0051] S602: using a first-in-first-out queue to average process the effective echo signal data in each window to obtain a dynamic threshold of the noise floor.

[0052] It should be noted that the dynamic threshold is self-adaptively adjusted according to the data of the sliding window to adapt to the change of different signal strengths.

[0053] In the embodiment of the present application, by averaging the effective echo signal data in each window, the influence of noise can be effectively reduced, because noise is usually random, and after averaging, the noise is smoothed, and the effective signal is enhanced.

[0054] S603: A fixed coefficient is superimposed on the dynamic threshold to adjust the sensitivity of the dynamic threshold to obtain a sensitive dynamic threshold.

[0055] It should be noted that the fixed value is a constant, which is used to further adjust the sensitivity of the threshold to ensure that the system will not mistakenly judge noise as effective signal.

[0056] In the embodiment of the present application, superimposing the fixed coefficient can increase or decrease the sensitivity of the threshold. This is very useful for signal detection in different scenarios, for example, when the environmental noise is high, the sensitivity of the threshold can be increased to avoid false detection; in the case of small noise or weak signal, the sensitivity can be reduced to avoid missing important signals.

[0057] S604: Determine whether the maximum value of the effective echo signal data in the first-in first-out queue is greater than the sensitive dynamic threshold. If yes, record the position information of the current effective echo signal, and proceed to the next step. Otherwise, continue to detect until all the effective echo signal data are detected.

[0058] In the embodiment of the present application, by comparing the maximum value with the sensitive dynamic threshold, the system can ensure that only when the amplitude of the signal exceeds a certain preset standard, the signal can be considered as an effective signal. This judgment mechanism can effectively filter out noise smaller than the threshold, and ensure that only echo signals with sufficient strength are detected.

[0059] S605: According to the position information of the current effective echo signal, the accurate arrival time of the effective echo signal is calculated.

[0060] In a possible implementation, the calculation formula of the accurate arrival time of the effective echo signal is specifically:

[0061] Wherein, t T represents the accurate arrival time of the effective echo signal, t end T represents the arrival time of the effective echo signal, t start T represents the start time of the effective echo signal.

[0062] Specifically, the data with the length of 257 is averaged by using two FIFOs to obtain a dynamic threshold, and then a fixed value CThres is superimposed, and compared with the maximum value point in the middle of the FIFO, if B>A, the detection is successful, the information of the position is output, and the third formula is calculated, otherwise, the detection is continued until all the data are detected.

[0063] For example, the signal can be detected easily only when the signal is higher than the dynamic threshold in the position inside the box. According to the actual example of the waveform in the above figure, the echo arrival time is .

[0064] Referring to the accompanying drawings in the description Figure 3 , a raw signal waveform diagram for removing reverse overshoot is shown.

[0065] S7: determining the actual distance of the to-be-detected target from the laser based on the accurate arrival time.

[0066] In a possible implementation, S7 specifically includes: determining the actual distance from the to-be-detected target based on the accurate arrival time by using the following formula:

[0067] wherein, d the actual distance of the to-be-detected target, c the speed of light, t the accurate arrival time of the effective echo signal.

[0068] For example, the actual distance can be calculated according to the speed of light 3e8 m / s. .

[0069] In the embodiment of the present application, the actual distance of the target is calculated based on the accurate arrival time, and the speed of light formula is used to ensure high accuracy and high efficiency of distance measurement. This method is simple and real-time, can quickly adapt to dynamic environment, and avoid error accumulation, and is suitable for measurement requirements in long distance and complex environment.

[0070] The technical scheme provided by the embodiment of the present application has at least the following beneficial effects: In the embodiment of the present application, the stability of the echo signal is enhanced by sampling the echo signal multiple times and performing in-phase combination, and the influence of the interference signal is effectively eliminated by using the overshoot removal processing technology. Combined with in-phase combination and overshoot removal processing, the accurate effective echo signal is obtained, the problem of small signal loss or false detection caused by reverse overshoot in the prior art is avoided, and the ranging accuracy is significantly improved.

[0071] With reference to the accompanying drawings Figure 4 , a structure schematic diagram of a pulse laser ranging system based on reverse overshoot suppression provided by an embodiment of the present application is shown.

[0072] An embodiment of the present application provides a pulse laser ranging system 20 based on reverse overshoot suppression, comprising a processor 201 and a memory 202. The memory 202 stores programs or instructions executable on the processor 201, the programs or instructions are executed by the processor 201 to realize the steps of the pulse laser ranging method based on reverse overshoot suppression described above, and the same technical effects can be achieved, to avoid repetition, the present application will not repeat the present application will not repeat.

[0073] It should be understood that the processor 201 in the embodiment of the present application can be a central processing unit (CPU), and the processor can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), ready programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0074] It is also to be understood that the memory 202 in embodiments of the present application can be volatile or nonvolatile memory, or can include both volatile and nonvolatile memory. Nonvolatile memory can be read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically EPROM (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), used as external cache. By way of example, and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0075] The above-described embodiments can be implemented in whole or in part by software, hardware (e.g., circuitry), firmware, or any combination of the three. When implemented in software, the above-described embodiments can be implemented in the form of one or more computer programs that are stored in a computer-readable storage medium. The computer-readable storage medium can be loaded into a computer, and the computer can execute the computer program to wholly or partially produce the processes or functions described in the embodiments of the present application. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable apparatus. The computer program can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium, for example, the computer program can be transferred from one website, computer, server, or data center to another website, computer, server, or data center through a wired (e.g., infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that includes one or a collection of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium can be a solid-state disk.

[0076] It should be understood that the size of the sequence number of each process described above in various embodiments of the present application does not mean the order of execution, and the execution order of each process should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0077] Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be realized in electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Those of ordinary skill in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0078] Those of ordinary skill in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the devices, apparatuses and units described above can refer to the corresponding processes in the foregoing method embodiments, which will not be described here.

[0079] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other manners. For example, the embodiments of the apparatus described above are merely schematic. For example, the division of the units is only a logical function division. There can be another division manner for the actual implementation, for example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections between the units can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0080] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, can be located in one place, or can be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiments.

[0081] In addition, each functional unit in the various embodiments of the present application can be integrated into a processing unit, or each unit can exist physically, or two or more units can be integrated into one unit.

[0082] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts of the present application that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0083] The embodiments of the present application provide a readable storage medium, which includes: a program or instructions stored on the readable storage medium, the program or instructions are executed by a processor to realize the steps of the above-mentioned reverse overshoot suppression based pulse laser ranging method, and the same technical effects can be achieved. To avoid repetition, the present application will not be described again.

[0084] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present application, but not to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application. Any changes or replacements that can be easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered within the protection scope of the present application.

Claims

1. A pulsed laser ranging method based on reverse overshoot suppression, characterized in that, include: S1: Obtain the target to be detected; S2: Emit laser pulses toward the target to be detected using a laser; S3: Sample the echo signal reflected from the target to be detected multiple times; S4: Combine the echo signals sampled multiple times in phase to obtain a stable echo signal; S5: Remove the reverse overshoot from the stable echo signal to obtain an effective echo signal; S6: Perform energy detection analysis on the effective echo signal and calculate the precise arrival time of the effective echo signal; S7: Based on the precise arrival time, determine the actual distance between the target to be detected and the laser.

2. The pulsed laser ranging method based on reverse overshoot suppression according to claim 1, characterized in that, The echo signal acquired in a single acquisition is specifically as follows: ； in, y n Indicates the first n The echo signal acquired in this second acquisition Indicates the first n The Mth sampling point of the echo signal M Indicates the sampling length of the echo signal. N This indicates the total number of samples.

3. The pulsed laser ranging method based on reverse overshoot suppression according to claim 2, characterized in that, S4 specifically includes: S401: Superimpose the echo signals acquired each time at the same time point and calculate the average signal at each time point: ； in, Indicates the first m The average signal at each time point Indicates the first N -1st collection m Echo signals at each time point; S402: Arrange the average signals at each time point in chronological order to obtain the stable echo signal: ； in, Indicates a stable echo signal. Indicates the first M -1 is the average signal at one time point.

4. The pulsed laser ranging method based on reverse overshoot suppression according to claim 1, characterized in that, S5 specifically includes: S501: The stable echo signal is weighted and averaged using a smoothing window to obtain a smoothed signal; S502: Subtract the smoothed signal from the stable echo signal to remove the reverse overshoot interference generated when the laser is emitted, and obtain the effective echo signal.

5. The pulsed laser ranging method based on reverse overshoot suppression according to claim 4, characterized in that, Specifically, S502 is as follows: The effective echo signal is obtained by subtracting the smoothed signal from the stable echo signal using the following formula to remove the reverse overshoot interference generated during laser emission: ； in, Indicates a valid echo signal. Indicating the first stable echo signal n The average value at each time point Indicates the first n + m Stable echo signal values ​​at each time point m Index representing a point in time.

6. The pulsed laser ranging method based on reverse overshoot suppression according to claim 5, characterized in that, S6 specifically includes: S601: The effective echo signal is segmented using a sliding window method; S602: The effective echo signal data in each window is averaged using a first-in-first-out queue to obtain the dynamic threshold of the noise floor; S603: A fixed coefficient is superimposed on the dynamic threshold to adjust the sensitivity of the dynamic threshold, thereby obtaining a sensitive dynamic threshold; S604: Determine whether the maximum value of the valid echo signal data in the first-in-first-out queue is greater than the sensitive dynamic threshold; if so, record the position information of the current valid echo signal and proceed to the next step; otherwise, continue detection until all valid echo signal data have been detected. S605: Calculate the precise arrival time of the valid echo signal based on the location information of the current valid echo signal.

7. The pulsed laser ranging method based on reverse overshoot suppression according to claim 6, characterized in that, The formula for calculating the precise arrival time of the effective echo signal is as follows: ； in, t Indicates the precise arrival time of the valid echo signal. t end Indicates the arrival time of the valid echo signal. t start Indicates the start time of the valid echo signal.

8. The pulsed laser ranging method based on reverse overshoot suppression according to claim 1, characterized in that, Specifically, S7 is: Based on the precise arrival time, the actual distance to the target to be detected is determined using the following formula: ； in, d This indicates the actual distance to the target being detected. c Represents the speed of light. t This indicates the precise arrival time of the valid echo signal.

9. A pulsed laser ranging system based on reverse overshoot suppression, characterized in that, include: Processor and memory; The memory stores programs or instructions that can run on the processor, which, when executed by the processor, implement the steps of the pulsed laser ranging method based on reverse overshoot suppression as described in any one of claims 1 to 8.

10. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the pulsed laser ranging method based on reverse overshoot suppression as described in any one of claims 1 to 8.

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