WO2023125321A1

WO2023125321A1 - Signal processing method and apparatus of laser radar, and storage medium

Info

Publication number: WO2023125321A1
Application number: PCT/CN2022/141597
Authority: WO
Inventors: 刘登科; 赵文
Original assignee: 武汉万集光电技术有限公司
Priority date: 2021-12-30
Filing date: 2022-12-23
Publication date: 2023-07-06
Also published as: CN116413699A

Abstract

A signal processing method of a laser radar. The method comprises: transmitting a plurality of pulse signals, and acquiring monitoring signals which correspond to the plurality of pulse signals (S101); on the basis of the monitoring signals, determining whether the plurality of pulse signals have echo signals (S102); if the plurality of pulse signals have echo signals, processing the echo signals according to signal features of the echo signals, so as to obtain processed signals (S103); if none of the plurality of pulse signals has an echo signal, superimposing the monitoring signals, and determining processed signals according to the superimposed monitoring signals (S104); and calculating the return time of the plurality of pulse signals according to the processed signals (S105). Further related are a signal processing apparatus of a laser radar, and a laser radar device (600) and a computer-readable storage medium (620).

Description

Laser radar signal processing method, device and storage medium

This application claims the priority of the Chinese patent application with the application number 202111657210.4 and the application title "Signal processing method, device and storage medium for laser radar" submitted to the State Intellectual Property Office on December 30, 2021, the entire content of which is incorporated by reference incorporated in this application.

technical field

The present application belongs to the technical field of radar, and in particular relates to a laser radar signal processing method, device and storage medium.

Background technique

Lidar is a radar system that detects the position, speed and other characteristic quantities of a target by emitting a laser beam. Its working principle is to launch a laser beam to the target, and then compare the received echo signal reflected from the target with the transmitted signal, and after proper processing, the relevant information of the target (such as target distance, azimuth, height, etc.) can be obtained. , speed, attitude, and even shape parameters), so as to detect, track and recognize the target.

Ranging accuracy and detection capability are important indicators of lidar performance. Improving the ranging accuracy and detection capability of LiDAR can be achieved by increasing laser output power, reducing circuit noise, and improving the conversion efficiency of photodetectors. However, limited by hardware, size, power consumption, heat generation, cost, and human eye safety, it is more or less difficult to improve the ranging accuracy and detection capabilities of lidar through the above methods.

Contents of the invention

In view of this, embodiments of the present application provide a laser radar signal processing method, device, and storage medium, so as to improve the ranging accuracy and detection capability of the laser radar.

The first aspect of the embodiments of the present application provides a laser radar signal processing method, including:

transmitting a plurality of pulse signals, and obtaining monitoring signals corresponding to the plurality of pulse signals;

judging whether there are echo signals in a plurality of the pulse signals based on the monitoring signal;

If the echo signal exists in a plurality of the pulse signals, the echo signal is processed according to the signal characteristics of the echo signal to obtain a processed signal;

If the echo signal does not exist in a plurality of the pulse signals, superimposing the monitoring signal, and determining the processed signal according to the superimposed monitoring signal;

and calculating return times of a plurality of pulse signals according to the processed signals.

The second aspect of the embodiment of the present application provides a laser radar signal processing device, including:

A pulse signal transmitting module, configured to transmit multiple pulse signals;

A monitoring signal acquisition module, configured to acquire monitoring signals corresponding to a plurality of the pulse signals;

An echo signal judging module, configured to judge whether there are echo signals in a plurality of the pulse signals based on the monitoring signal;

A first signal processing module, configured to process the echo signal according to the signal characteristics of the echo signal to obtain a processed signal if the echo signal exists in a plurality of the pulse signals;

The second signal processing module is configured to superimpose the monitoring signal if none of the plurality of pulse signals has the echo signal, and determine the processed signal according to the superimposed monitoring signal;

A return time calculation module, configured to calculate the return time of multiple pulse signals according to the processed signal.

A third aspect of the embodiments of the present application provides a laser radar device, including a memory, a processor, and a computer program stored in the memory and operable on the processor, and the processor executes the computer program Realize the signal processing method of the laser radar as described in the first aspect above.

The fourth aspect of the embodiments of the present application provides a computer-readable storage medium, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the laser radar as described in the first aspect above is realized signal processing method.

The fifth aspect of the embodiment of the present application provides a computer program product, when the computer program product is run on the laser radar device, the laser radar device is made to execute the signal processing method of the laser radar described in the first aspect above .

Compared with the prior art, the embodiment of the present application has the following advantages:

In the embodiment of the present application, when the lidar device detects the target object, it may detect the target object by transmitting multiple pulse signals. For the acquired monitoring signals corresponding to multiple pulse signals, the lidar device can determine whether they are suitable for superposition by judging whether there are echo signals among the multiple pulse signals before superimposing them. For signals that are suitable for superimposition, the processed signal can be obtained by superposition; for signals that are not suitable for superposition, the current signal can be used as the processed signal through further processing or directly. The return time of the pulse signal calculated based on the signal processed in this way is more accurate than the return time obtained by directly superimposing the signals in the prior art, which improves the ranging accuracy and detection capability of the laser radar.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Apparently, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a laser radar signal processing method provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of an implementation of step S103 in a laser radar signal processing method provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of an implementation of step S104 in a laser radar signal processing method provided in an embodiment of the present application;

FIG. 4 is a schematic diagram of a signal processing flow of a lidar provided in an embodiment of the present application;

FIG. 5 is a schematic diagram of a laser radar signal processing device provided in an embodiment of the present application;

Fig. 6 is a schematic diagram of a lidar device provided by an embodiment of the present application.

Detailed ways

In the following description, specific details such as specific system structures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

Generally, if you want to improve the ranging accuracy and detection ability of lidar, you can improve the signal-to-noise ratio of the signal. Compared with increasing the laser output power, reducing circuit noise, and improving the conversion efficiency of photodetectors, etc., which are easily limited by hardware, volume, power consumption, heat generation, cost, and human eye safety, it is easier to increase the signal-to-noise ratio of the signal. A way of realizing it. Wherein, the method of signal superposition is used to improve the signal-to-noise ratio of the signal.

Let the i-th signal be:

y _i (m) = s _i (m) + n _i (m)

Among them, y is the monitored signal, s is the real signal, n is the signal noise, and m is the sampling point in the signal.

When K signals are superimposed, there is:

It can be seen from the above formula that after K signals are superimposed, the real signal can become K times the original, namely:

Among them, E is the expected value.

Assuming that the signal noise is Gaussian white noise, then:

Wherein, i and j are different signals respectively.

Since the noises are not correlated with each other, when i≠j, there is

Thus, the above expression can be expressed as:

And then get:

It can be seen that by superimposing the signal, the signal noise becomes the original

times.

Let the signal-to-noise ratio be:

Among them, A is the amplitude of the signal, σ is the root mean square of the signal noise.

Then, after superimposing the K signals, the signal-to-noise ratio is:

That is to say, after adding K signals, the signal-to-noise ratio will increase

times.

Usually, since the emissivity of the same target object is almost equal, the distance between each scanning point marked by the laser radar device on the target object and the laser radar device is also almost equal, so it can be considered that the echo signals returned by these scanning points are also basically the same. However, on the other hand, when multiple adjacent scanning points are not on the same target object, the echo signals may not be at the same position due to distance deviation. If these signals are directly superimposed, the superimposed signal may not only The signal-to-noise ratio cannot be improved, and it may also cause changes in the shape of the original signal, resulting in inaccurate ranging. Therefore, the embodiment of the present application provides a laser radar signal processing method, by judging whether there is an echo signal in the pulse signal emitted by the laser radar, and superimposing the signals suitable for superimposition in a targeted manner, which can be used without changing the laser radar In the case of limited hardware, volume, power consumption, heat generation, cost, human eye safety and other constraints, the ranging accuracy and detection ability of the radar can be improved.

The technical solutions of the present application are illustrated below through specific examples.

Referring to FIG. 1 , it shows a schematic diagram of a laser radar signal processing method provided by an embodiment of the present application. The method may specifically include the following steps:

S101. Transmit multiple pulse signals, and acquire monitoring signals corresponding to the multiple pulse signals.

It should be noted that this method can be applied to a laser radar device, that is, the implementation body of the embodiments of the present application is a laser radar device.

In the embodiment of the present application, the laser radar device may transmit multiple pulse signals during the detection process. These pulse signals will be reflected after hitting the target object, and the reflected signal can be received by the laser radar device. The signal received by the lidar device is the monitoring signal. Usually, the monitoring signal can be composed of real signal and noise.

In a possible implementation manner of the embodiment of the present application, transmitting multiple pulse signals may be implemented by simultaneously transmitting multiple pulse signals at one time. For example, for a certain scanning point, K pulse signals may be transmitted to the scanning point at the same time. In this way, the laser radar device can also obtain the K monitoring signals returned by the scanning point.

In another possible implementation manner of the embodiment of the present application, transmitting multiple pulse signals may also be implemented by transmitting one pulse signal at a time for multiple scanning points. For example, for K scanning points, a pulse signal is transmitted to each scanning point each time. In this way, the laser radar device can also obtain K monitoring signals returned by K scanning points.

In yet another possible implementation manner of the embodiment of the present application, the above two transmission manners may also be combined. For example, M pulse signals are transmitted each time, and K monitoring signals can also be obtained by storing the monitoring signals returned from the previous N transmissions. Among them, K=M*N.

S102. Determine whether echo signals exist in the plurality of pulse signals based on the monitoring signal.

Usually, the monitoring signal can form a corresponding waveform, through which it can be judged whether the monitoring signal received by the lidar device is an echo signal.

In a specific implementation, a corresponding determination threshold may be set, and whether the monitoring signal is an echo signal is determined in combination with the waveform of the monitoring signal and the determination threshold. This process is to judge whether there is an echo signal in the pulse signal emitted by the laser radar device.

According to the judgment result of whether there is an echo signal in the pulse signal emitted by the laser radar device, different processing methods can be used to process the signal. Wherein, if echo signals exist in multiple pulse signals, S103 may be performed; if echo signals do not exist in any of the multiple pulse signals, S104 may be performed.

S103. Process the echo signal according to the signal characteristics of the echo signal to obtain a processed signal.

In the embodiment of the present application, when there is an echo signal in the transmitted pulse signal, different signal processing methods may be adopted according to the signal characteristics of the echo signal. Wherein, the signal feature of the echo signal may include at least one of the following feature items: the position of the rising edge of the echo signal, the peak value of the echo signal, the peak position of the echo signal, the pulse width of the echo signal, or the adjacent echo signal The sum of squares of the deviations between them is not limited in this embodiment of the present application.

In a possible implementation of the embodiment of the present application, multiple pulse signals have echo signals, which may include two situations, namely: multiple pulse signals all have echo signals; or, multiple pulse signals have echo signals partially Signal. Therefore, when the echo signal is processed according to its signal characteristics, the above two situations can also be processed separately.

As shown in Figure 2, in S103, the echo signal is processed according to the signal characteristics of the echo signal to obtain the processed signal, which may specifically include the following sub-steps S1031-S1033:

S1031. If echo signals exist in all the pulse signals, determine a feature item to be compared from signal features of the echo signals.

In the embodiment of the present application, the feature item to be compared may be any feature item among the signal features of the echo signal. For example, the feature item to be compared may be the rising edge position of the echo signal, or the peak value of the echo signal, or the peak position of the echo signal, etc., which is not limited in this embodiment of the present application.

If there are echo signals among the multiple pulse signals emitted by the lidar, the feature item to be compared can be determined first. After the feature item to be compared is determined, it can be further judged whether the feature item satisfies a preset condition. It should be noted that, for different feature items, the corresponding preset conditions may be different.

S1032. When the feature items of the plurality of echo signals all satisfy the preset condition, superimpose the plurality of echo signals to obtain the processed signal.

In the embodiment of the present application, if the feature items of the multiple echo signals all meet the preset conditions, it can be considered that the received echo signals are transmitted by the same target object, that is, these echo signals belong to the same target. Correspondingly, these echo signals can also be superimposed.

Taking the feature item as the rising edge position of the echo signal as an example, when judging whether the feature item satisfies the preset condition, it can be judged whether the rising edge position of each echo signal is within a certain set range. If the rising edge positions of these echo signals are all within the range, it can be considered that the characteristic item satisfies the preset condition. For other characteristic items, the method of judging whether they meet the preset conditions is similar to this.

It should be noted that the superposition of signals described in the embodiments of the present application includes two steps of superposition and averaging. Therefore, when it is determined that the feature item satisfies the preset condition, the echo signals can be superimposed first, and then the superimposed signals can be averaged to obtain the processed signal. Since superimposing signals is a relatively mature signal processing method in the prior art, this embodiment of the present application will not describe it in detail.

S1033. If there is a feature item of the echo signal that does not meet the preset condition, determine a signal to be superimposed from a plurality of echo signals, and superimpose the signal to be superimposed to obtain the processed signals; wherein, the number of the signals to be superimposed is smaller than the number of the echo signals.

If the feature items of the echo signals do not meet the preset conditions, it can be considered that these echo signals cannot be directly superimposed.

In the embodiment of the present application, for echo signals that cannot be directly superimposed, part of the echo signals may be superimposed by reducing the number of superimposed signals.

In a specific implementation, when it is determined that the feature item of the echo signal does not satisfy the preset condition, the signal to be superimposed may be firstly determined from the plurality of echo signals. The number of these signals to be superimposed is smaller than the number of echo signals.

In an example, the signals to be superimposed may be those echo signals whose feature items satisfy the aforementioned preset conditions. For example, also taking the characteristic item as an example of the rising edge position of the echo signal, it may be determined whether the rising edge position of each echo signal is within a certain set range. Then those echo signals whose rising edge positions are within this range are determined as signals to be superimposed. Then, superimpose the signal to be superimposed to obtain the processed signal.

In a possible implementation of the embodiment of the present application, if there are echo signals in multiple pulse signals, but the characteristic items of these echo signals do not meet the preset conditions, it can also be considered that the echo signals cannot be superimposed, Therefore, the current signal is directly used as the processed signal to perform subsequent signal processing operations. Wherein, the current signal may be an echo signal that is currently received and cannot be superimposed with other echo signals.

In the embodiment of the present application, if the plurality of pulse signals emitted by the lidar only partially have echo signals, it is also possible to superimpose only the received echo signals by reducing the number of superimposed signals to obtain a processed signal; Alternatively, the echo signal may also be directly used as the processed signal, which is not limited in this embodiment of the present application.

S104. Superimpose the monitoring signal, and determine the processed signal according to the superimposed monitoring signal.

If there is no echo signal among the multiple pulse signals emitted by the lidar device, it can be considered that the target object is far away or the reflectivity of the target object is too low. At this time, the acquired monitoring signals may be directly superimposed, and a processed signal may be determined according to the superimposed monitoring signals for subsequent signal processing operations.

In the embodiment of the present application, superimposing the obtained monitoring signals is similar to the method of superimposing the echo signals in the above steps, that is, first superimposing multiple monitoring signals, and then averaging the superimposed monitoring signals deal with.

As shown in Figure 3, in S104, the monitoring signal is superimposed, and the processed signal is determined according to the superimposed monitoring signal, which may specifically include the following sub-steps S1041-S1044:

S1041. Superimpose the monitoring signal.

S1042. Determine whether the echo signal exists in the superimposed monitoring signal based on a first preset determination threshold.

In this embodiment of the present application, the first preset determination threshold may be a relatively low echo signal determination threshold. Exemplarily, if in S102 it is determined based on the monitoring signal whether there is an echo signal in a plurality of pulse signals is determined by the second preset determination threshold, then this step is used to determine whether there is an echo signal in the superimposed monitoring signal The first preset decision threshold may be a certain value smaller than the above-mentioned second preset decision threshold.

If it is determined based on the above-mentioned first preset determination threshold that there is an echo signal in the superimposed monitoring signal, S1043 can be executed to determine the superimposed monitoring signal as a processed signal; otherwise, S1044 can be executed to directly discard the superimposed monitoring signal. Signal, end the signal processing flow.

S1043. Determine the superimposed monitoring signal as the processed signal.

S1044. Discard the superimposed monitoring signal.

S105. Calculate return times of multiple pulse signals according to the processed signals.

For the processed signal obtained through the aforementioned steps, the laser radar device can calculate the return time of multiple pulse signals based on the processed signal, so as to determine the distance, orientation, height, speed, Parameters such as pose and even shape.

In a possible implementation manner of the embodiment of the present application, the lidar device may use the intersection of the preset percentage of the peak value of the processed signal and the rising edge of the signal as the return time of the multiple pulse signals. The foregoing preset percentage may be determined according to actual needs, for example, 60%, 80%, etc., which is not limited in this embodiment of the present application.

In the embodiment of the present application, when the laser radar device detects the target object, it may perform the detection by transmitting multiple pulse signals. For the acquired monitoring signals corresponding to multiple pulse signals, the lidar device can determine whether they are suitable for superposition by judging whether there are echo signals among the multiple pulse signals before superimposing them. For signals that are suitable for superimposition, the processed signal can be obtained by superposition; for signals that are not suitable for superposition, the current signal can be used as the processed signal through further processing or directly. The return time of the pulse signal calculated based on the signal processed in this way is more accurate than the return time obtained by directly superimposing the signals in the prior art, which improves the ranging accuracy and detection capability of the laser radar.

It should be noted that the sequence numbers of the steps in the above embodiments do not mean the order of execution, the execution order of each process should be determined by its functions and internal logic, and should not constitute any limited.

For ease of understanding, the signal processing method of the lidar provided in the embodiment of the present application is introduced below with a complete example.

As shown in FIG. 4 , it is a schematic diagram of a signal processing flow of a lidar provided in an embodiment of the present application. The signal processing flow of the lidar shown in Figure 4 may include the following steps:

S1. The lidar device transmits M pulse signals each time, and stores K=M*N signals received in the previous N times. The above K signals are the signals reflected by the target object received by the lidar device after transmitting the pulse signal, that is, the monitoring signals in the aforementioned method embodiments.

S2. The lidar device judges whether echoes exist in the K signals. The lidar device may judge whether there are echoes in the K signals based on the set judgment threshold, and the judgment result may include whether there are echo signals or no echo signals. Wherein, the existence of the echo signal can be further divided into two situations that all of the K signals have the echo signal, and that only some of the K signals have the echo signal.

S3. If there are echo signals in all the K signals, compare the signal characteristics of their echo signals to determine whether they meet the preset conditions. The signal characteristics may include any of the following feature items: the position of the rising edge of the echo signal, the peak value of the echo signal, the position of the peak value of the echo signal, the pulse width of the echo signal, or the sum of the squares of the deviations between adjacent echo signals . When comparing signal features, one of the feature items can be selected for comparison to determine whether it satisfies a preset condition, or multiple feature items can be selected for comparison. If the signal features all meet the preset conditions, it is considered that the echo signal can be superimposed. Therefore, the K echo signals can be superimposed and averaged, and then jump to step S6; if there is a signal characteristic of the echo signal that does not meet the preset condition, then jump to step S5.

S4. If there is no echo signal among the K signals, it is considered that the target object is far away or the reflectivity is too low. At this point, the K signals can be directly superimposed and averaged. Then, the decision threshold for judging whether there is an echo signal is lowered, and based on the lowered decision threshold, it is judged whether there is an echo signal in the superimposed signal. If there is an echo signal in the superimposed signal, the superimposed signal may be used as the processed signal, and the procedure goes to step S6.

S5. If only some of the K signals have echo signals, or if the signal characteristics of the echo signals do not meet the preset conditions, then the number of superimposed signals can be reduced, or it is directly considered that these K signals cannot be superimposed, and the current The signal is used as a processed signal, and the process goes to step S6.

S6. Taking the intersection of a certain percentage of the peak value of the processed signal and its rising edge as the signal return time.

Referring to FIG. 5 , it shows a schematic diagram of a laser radar signal processing device provided by an embodiment of the present application. The device may specifically include a pulse signal transmitting module 501, a monitoring signal acquiring module 502, an echo signal judging module 503, a first Signal processing module 504, second signal processing module 505, return time calculation module 506, wherein:

A pulse signal transmitting module 501, configured to transmit multiple pulse signals;

A monitoring signal acquisition module 502, configured to acquire monitoring signals corresponding to a plurality of pulse signals;

An echo signal judging module 503, configured to judge whether there are echo signals in a plurality of the pulse signals based on the monitoring signal;

The first signal processing module 504 is configured to process the echo signal according to the signal characteristics of the echo signal to obtain a processed signal if the echo signal exists in a plurality of the pulse signals;

The second signal processing module 505 is configured to superimpose the monitoring signal if none of the plurality of pulse signals has the echo signal, and determine the processed signal according to the superimposed monitoring signal;

A return time calculation module 506, configured to calculate the return time of multiple pulse signals according to the processed signal.

In the embodiment of the present application, the first signal processing module 504 can be specifically configured to: if the echo signals exist in a plurality of the pulse signals, determine the signal to be compared from the signal characteristics of the echo signals. A characteristic item; when the characteristic items of the plurality of echo signals all meet the preset conditions, then superimposing the plurality of echo signals to obtain the processed signal; if there is a characteristic of the echo signal When the item does not meet the preset condition, the signal to be superimposed is determined from a plurality of echo signals, and the signal to be superimposed is superimposed to obtain the processed signal; wherein, the signal to be superimposed The number of is less than the number of echo signals.

In the embodiment of the present application, the first signal processing module 504 may also be configured to: if there is a characteristic item of the echo signal that does not meet the preset condition, then use the current signal as the processed signal; Wherein, the current signal is an echo signal that is currently received and cannot be superimposed with other echo signals.

In this embodiment of the application, the signal features may include at least one of the following feature items:

The position of the rising edge of the echo signal, the peak value of the echo signal, the position of the peak value of the echo signal, the pulse width of the echo signal, or the sum of squares of deviations between adjacent echo signals.

In the embodiment of the present application, the first signal processing module 504 may also be configured to: if the echo signals exist in a plurality of the pulse signal parts, superimpose the received echo signals to obtain the the processed signal; or, use the echo signal as the processed signal.

In the embodiment of the present application, the second signal processing module 505 may be specifically configured to: judge whether the superimposed monitoring signal has the echo signal based on a first preset judgment threshold; wherein, the first preset The determination threshold is set to be smaller than the second preset determination threshold for judging whether there are echo signals in a plurality of pulse signals based on the monitoring signal; if the superimposed monitoring signal exists based on the first preset determination threshold For the echo signal, determine the superimposed monitoring signal as the processed signal; otherwise, discard the superimposed monitoring signal.

In the embodiment of the present application, the return time calculation module 506 can be specifically configured to: use the intersection points of the preset percentage of the peak value of the processed signal and the rising edge of the processed signal as multiple The return time of the pulse signal.

As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for related details, please refer to the description of the method embodiment.

Referring to FIG. 6 , it shows a schematic diagram of a lidar device provided by an embodiment of the present application. As shown in FIG. 6 , the lidar device 600 in the embodiment of the present application includes: a processor 610 , a memory 620 , and a computer program 621 stored in the memory 620 and operable on the processor 610 . When the processor 610 executes the computer program 621 , the steps in the various embodiments of the signal processing method of the above-mentioned lidar are implemented, such as steps S101 to S105 shown in FIG. 1 . Alternatively, when the processor 610 executes the computer program 621, functions of the modules/units in the above-mentioned device embodiments, for example, the functions of the modules 501 to 506 shown in FIG. 5 , are implemented.

Exemplarily, the computer program 621 can be divided into one or more modules/units, and the one or more modules/units are stored in the memory 620 and executed by the processor 610 to complete this application. The one or more modules/units may be a series of computer program instruction segments capable of accomplishing specific functions, and the instruction segments may be used to describe the execution process of the computer program 621 in the lidar device 600 . For example, the computer program 621 can be divided into a pulse signal transmission module, a monitoring signal acquisition module, an echo signal judgment module, a first signal processing module, a second signal processing module, and a return time calculation module. The specific functions of each module are as follows:

The lidar device 600 may be the lidar described in the foregoing method embodiments, and the lidar device 600 may include, but not limited to, a processor 610 and a memory 620 . Those skilled in the art can understand that FIG. 6 is only an example of the laser radar device 600, and does not constitute a limitation to the laser radar device 600. It may include more or less components than those shown in the figure, or combine certain components, Or different components, for example, the lidar device 600 may also include an input and output device, a network access device, a bus, and the like.

The processor 610 can be a central processing unit (Central Processing Unit, CPU), and can also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Off-the-shelf programmable gate array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

The memory 620 may be an internal storage unit of the lidar device 600 , such as a hard disk or memory of the lidar device 600 . The memory 620 can also be an external storage device of the laser radar device 600, such as a plug-in hard disk equipped on the laser radar device 600, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, flash memory card (Flash Card) and so on. Further, the memory 620 may also include both an internal storage unit of the lidar device 600 and an external storage device. The memory 620 is used to store the computer program 621 and other programs and data required by the lidar device 600 . The memory 620 can also be used to temporarily store data that has been output or will be output.

The embodiment of the present application also discloses a laser radar device, including a memory, a processor, and a computer program stored in the memory and operable on the processor, when the processor executes the computer program, the following is realized: The laser radar signal processing method described in the foregoing embodiments.

The embodiment of the present application also discloses a computer-readable storage medium, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it realizes the signal processing of the laser radar as described in the foregoing embodiments method.

The embodiment of the present application also discloses a computer program product. When the computer program product is run on a laser radar device, the laser radar device is made to execute the laser radar signal processing method described in the foregoing embodiments.

The above-mentioned embodiments are only used to illustrate the technical solution of the present application, but not to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that: they can still modify the technical solutions described in the aforementioned embodiments, or perform equivalent replacements for some of the technical features; and these Any modification or replacement that does 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 shall be included within the protection scope of the present application.

Claims

A signal processing method for laser radar, characterized in that, comprising:

transmitting a plurality of pulse signals, and obtaining monitoring signals corresponding to the plurality of pulse signals;

judging whether there are echo signals in a plurality of the pulse signals based on the monitoring signal;

If the echo signal exists in a plurality of the pulse signals, the echo signal is processed according to the signal characteristics of the echo signal to obtain a processed signal;

If the echo signal does not exist in a plurality of the pulse signals, superimposing the monitoring signal, and determining the processed signal according to the superimposed monitoring signal;

and calculating return times of a plurality of pulse signals according to the processed signals.
The method according to claim 1, characterized in that if the echo signals exist in a plurality of the pulse signals, the echo signals are processed according to the signal characteristics of the echo signals to obtain the processed After the signal, including:

If the echo signal exists in a plurality of the pulse signals, then determine the characteristic item to be compared from the signal characteristics of the echo signal;

When the feature items of the plurality of echo signals all meet the preset conditions, superimposing the plurality of echo signals to obtain the processed signal;

If there is a feature item of the echo signal that does not meet the preset condition, then determine a signal to be superimposed from a plurality of echo signals, superimpose the signal to be superimposed, and obtain the processed signal; wherein, the number of the signals to be superimposed is smaller than the number of the echo signals.
The method according to claim 2, further comprising:

If there is a characteristic item of the echo signal that does not meet the preset condition, the current signal is used as the processed signal; wherein, the current signal is currently received and cannot be superimposed with other echo signals echo signal.
The method according to claim 2 or 3, wherein the signal features include at least one of the following feature items:

The position of the rising edge of the echo signal, the peak value of the echo signal, the position of the peak value of the echo signal, the pulse width of the echo signal, or the sum of squares of deviations between adjacent echo signals.
The method according to claim 4, characterized in that if the echo signals exist in a plurality of the pulse signals, the echo signals are processed according to the signal characteristics of the echo signals to obtain the processed After the signal, also include:

If the echo signal exists in a plurality of the pulse signal parts, superimpose the received echo signal to obtain the processed signal; or, use the echo signal as the processed signal Signal.
The method according to claim 1, wherein the determining the processed signal according to the superimposed monitoring signal comprises:

Judging whether the echo signal exists in the superimposed monitoring signal based on a first preset determination threshold; wherein, the first preset determination threshold is smaller than the threshold used to determine whether a plurality of the pulse signals exist based on the monitoring signal a second preset judgment threshold of the echo signal;

If it is judged that the superimposed monitoring signal has the echo signal based on the first preset determination threshold, the superimposed monitoring signal is determined as the processed signal; otherwise, the superimposed monitoring signal is discarded. monitoring signal.
The method according to any one of claims 1-3 or 5-6, wherein the calculating the return time of a plurality of pulse signals according to the processed signal comprises:

The intersection of the preset percentage of the peak value of the processed signal and the rising edge of the processed signal is used as the return time of the plurality of pulse signals.
A signal processing device for laser radar, characterized in that it comprises:

A pulse signal transmitting module, configured to transmit multiple pulse signals;

A monitoring signal acquisition module, configured to acquire monitoring signals corresponding to a plurality of the pulse signals;

An echo signal judging module, configured to judge whether there are echo signals in a plurality of the pulse signals based on the monitoring signal;

A first signal processing module, configured to process the echo signal according to the signal characteristics of the echo signal to obtain a processed signal if the echo signal exists in a plurality of the pulse signals;

The second signal processing module is configured to superimpose the monitoring signal if none of the plurality of pulse signals has the echo signal, and determine the processed signal according to the superimposed monitoring signal;

A return time calculation module, configured to calculate the return time of multiple pulse signals according to the processed signal.
A laser radar device, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, wherein the computer program according to claim 1 is implemented when the processor executes the computer program. -The signal processing method of the lidar described in any one of 7.
A computer-readable storage medium, the computer-readable storage medium stores a computer program, characterized in that, when the computer program is executed by a processor, the signal of the laser radar according to any one of claims 1-7 is realized Approach.