Laser radar anti-interference method and device

Abstract

The embodiment of the invention discloses a laser radar anti-interference method and device, the laser radar anti-interference device can comprise a control module, a laser and a detector, the control module is used for determining N first sequences and N groups of first time intervals, and N is an integer greater than or equal to 1; the laser is used for transmitting N first laser signals according to the N first sequences and the N groups of first time intervals; the detector is used for receiving the N second laser signals and converting the N second laser signals into electric signals to obtain N first electric signals; and the control module is also used for superposing the N first electric signals to obtain a first superposed signal, and determining N second sequences and N groups of second time intervals according to the first superposed signal. According to the embodiment of the invention, the anti-interference capability of the laser radar can be improved.

Description

[0001] This application is a divisional application. The application number of the original application is 202110126177.6, and the original application date is January 29, 2021. The entire contents of the original application are incorporated into this application by reference. Technical Field

[0002] The embodiments of the present application relate to the field of optical communication technology, and in particular, to a laser radar anti-interference method and device. Background Art

[0003] LiDAR is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of a target. Its basic working principle is to first emit a detection laser beam to the target, then compare the emitted signal with the reflected signal received from the target, and obtain the target's distance, direction, height, speed, attitude, shape and other information based on the comparison results.

[0004] In reality, there are many interference sources that affect the performance of LiDAR. For example, sunlight, malicious co-frequency interference laser signals, multiple LiDARs with no synergy and using the same laser wavelength, etc. In order to solve the interference problem of LiDAR, LiDAR anti-interference technology came into being. At present, the common anti-interference method of pulsed LiDAR is to modulate the pulse amplitude, pulse width and pulse time interval, etc., so as to transmit a pulse signal carrying specific information. When receiving, a specific pulse signal that corresponds to the modulated pulse amplitude, pulse width and time interval is selected from the received signal as its own echo signal. Considering the issue of eye safety, the laser transmission power is limited, so the signal-to-noise ratio of the received signal is also limited. When LiDAR is used in an environment with interference, it is impossible to simply increase the laser transmission power to improve the anti-interference ability. In this case, the noise formed by the interference signal has a greater impact on the system, reducing the ranging performance of LiDAR. Summary of the invention

[0005] The embodiments of the present application disclose a laser radar anti-interference method and device for improving the anti-interference capability of the laser radar.

[0006] In a first aspect, a laser radar anti-interference device is disclosed, which may include a control module, a laser and a detector, wherein: the control module is used to determine N first sequences and N groups of first time intervals, N is an integer greater than or equal to 1; the laser is used to emit N first laser signals according to the N first sequences and the N groups of first time intervals; the detector is used to receive N second laser signals, convert the N second laser signals into electrical signals, and obtain N first electrical signals; the control module is also used to superimpose the N first electrical signals to obtain a first superimposed signal, and determine N second sequences and N groups of second time intervals according to the first superimposed signal.

[0007] In an embodiment of the present application, the first time interval can determine the sending time of the corresponding first sequence, and the interval length of the N groups of first time intervals is a random time length. Therefore, the time length of the sending time of the corresponding signals of the N first sequences is random. After the detector receives N second laser signals, the control module can superimpose the corresponding electrical signals according to the N groups of first time intervals to obtain a first superimposed signal. Compared with the directly received signal, the amplitude of the superimposed first superimposed signal will be greatly improved, which can improve the signal-to-noise ratio. At the same time, the sending time of the laser signal is random, which can avoid the accumulation of interference signals of fixed frequency. Therefore, the noise points in the point cloud map of the laser radar can be reduced, and the anti-interference ability of the laser radar can be improved.

[0008] As a possible implementation, the device may further include a signal generator, wherein: the signal generator is used to generate N second electrical signals according to the N first sequences and the N groups of first time intervals; the laser emitting N first laser signals according to the N first sequences and the N groups of first time intervals includes: the laser emitting N first laser signals according to the N second electrical signals.

[0009] In the embodiment of the present application, after the control module determines the first sequence and the first time interval, the signal generator can be used to achieve consistency between the first sequence and the sequence of the emitted first laser signal, thereby ensuring consistency between the first sequence and the sequence of the laser signal. In addition, the signal generator can determine the length of the time interval for sending N first laser signals by using N groups of first time intervals, thereby achieving randomness in the sending time. When the control module superimposes the signal, the accumulation of interference signals of fixed frequency can be avoided, thereby improving the signal-to-interference ratio of the superimposed signal.

[0010] As a possible implementation manner, when the N first sequences are the same sequence, the control module superimposes the N first electrical signals to obtain a first superimposed signal, including: superimposing the N first electrical signals according to the N groups of first time intervals to obtain a second superimposed signal; and filtering the second superimposed signal according to the N first sequences to obtain a first superimposed signal.

[0011] In the embodiment of the present application, the N first sequences are the same sequence, that is, the sequence of the N laser signals sent is the same laser sequence, but the N groups of first time intervals are random, and the time used for sending is different, so the corresponding electrical signals can be superimposed to obtain a second superimposed signal, and the signal amplitude of the superimposed signal is greatly improved after accumulation. At the same time, the sending time of the laser signal is random, so the accumulation of interference signals of fixed frequency can be reduced. Furthermore, since the second superimposed signal is formed by the superposition of corresponding signals of the same sequence, the superimposed signal can be directly filtered. After filtering, not only can the influence of the interference signal be further reduced and the anti-interference performance of the laser radar be improved, but also the number of filtering times can be reduced and the internal structure of the control module can be simplified.

[0012] As a possible implementation manner, when the N first sequences are different sequences, the control module superimposes the N first electrical signals to obtain a first superimposed signal, including: filtering the N first electrical signals according to the N first sequences to obtain N filtered signals; and superimposing the N filtered signals according to the N groups of first time intervals to obtain a first superimposed signal.

[0013] In the embodiment of the present application, the N first sequences are different sequences, that is, the sequences of the N laser signals sent are different laser sequences. Since the first superposition signal is a superposition signal of signals corresponding to different sequences, the probability of this laser radar and other laser radars using the same or similar sequences can be reduced to avoid interference caused by multiple laser radars using the same or similar sequences, thereby further improving the anti-interference ability of the laser radar. Due to the different sequences, the signals corresponding to different sequences can be filtered first, and then superimposed to form the first superposition signal, which can reduce the impact of interference signals, thereby improving the anti-interference performance of the laser radar.

[0014] As a possible implementation, the device further includes a spectroscope, and the control module includes a filter, wherein: the spectroscope is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, the third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes the fourth laser signal and the fifth laser signal; the detector is also used to receive N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N third electrical signals, and the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; the control module filters the second superimposed signal according to the N first sequences to obtain the first superimposed signal, comprising: the control module adjusts the filter coefficient of the filter according to the N third electrical signals; the filter filters the second superimposed signal according to the N first sequences to obtain the first superimposed signal.

[0015] In an embodiment of the present application, after the laser emits a laser signal, the emitted laser signal can be reflected and transmitted through a spectroscope to form two laser signals with the same sequence. Among them, one laser signal can be emitted to the detection object, and the other laser signal can be emitted directly to the detector. After the detector receives the signal directly emitted back, the filter coefficient of the filter can be adjusted, and the filter coefficient can correspond to the sequence actually sent by the laser. At this time, by adjusting the filter coefficient, the problem of reduced detection performance of the laser radar caused by internal interference of the device can be avoided, thereby improving the anti-interference ability of the laser radar.

[0016] As a possible implementation, the device further includes a spectroscope, and the control module includes a filter, wherein: the spectroscope is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, the third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes the fourth laser signal and the fifth laser signal; the detector is also used to receive N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N fourth electrical signals, and the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; the control module filters the N first electrical signals according to the N first sequences to obtain N filtered signals, including: the control module adjusts the filter coefficient of the filter according to the N fourth electrical signals; the filter filters the second superposition signal according to the N first sequences to obtain N filtered signals.

[0017] In an embodiment of the present application, after the laser emits a laser signal, the emitted laser signal can be reflected and transmitted through a spectroscope to form two laser signals with the same sequence. Among them, one laser signal can be emitted to the detection object, and the other laser signal can be emitted directly to the detector. After the detector receives the signal directly emitted back, the filter coefficient of the filter can be adjusted, and the filter coefficient can correspond to the sequence actually sent by the laser. At this time, by adjusting the filter coefficient, the problem of reduced detection performance of the laser radar caused by internal interference of the device can be avoided, thereby improving the anti-interference ability of the laser radar.

[0018] As a possible implementation manner, the control module determines N second sequences and N groups of second time intervals based on the first superimposed signal, including: when there is a correlation peak between the N first sequences and the first superimposed signal, and the value of the main-sidelobe ratio of the correlation peak is greater than a first threshold, the N first sequences are determined as the N second sequences, and the N groups of first time intervals are determined as the N groups of second time intervals.

[0019] In an embodiment of the present application, the control module can perform a cross-correlation operation on the first sequence and the first superposition signal. When there is a correlation peak in the result of the cross-correlation, it can be explained that the first superposition signal is an echo signal of the laser signal emitted by the corresponding first sequence. Further, when the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold value, it can be determined that the interference of the received echo signal is small and can meet the detection requirements of the system. When the detection requirements of the system can be met, the control module can determine that the N first sequences and N groups of first time intervals are suitable for the current environment, that is, the N first sequences and N groups of first time intervals can be determined as N second sequences and N groups of second time intervals. At this time, the current N first sequences and the current N groups of first time intervals are no longer adjusted, thereby reducing the processing overhead of the control module and improving the processing efficiency.

[0020] As a possible implementation, the control module determines N second sequences and N groups of second time intervals based on the first superposition signal and further includes: when the correlation peak exists and the value of the main-sidelobe ratio is less than or equal to the first threshold, increasing the interval length and / or the number of intervals included in each group of first time intervals in the N groups of first time intervals to obtain N groups of first time intervals.

[0021] In an embodiment of the present application, when there is a correlation peak in the result of the cross-correlation operation between the first sequence and the first superposition signal, it means that there is a certain degree of similarity between the N first sequences and the first superposition signal, and the control module can determine that the first superposition signal is the echo signal of the current N first sequences. Further, when the value of the main-sidelobe ratio of the correlation peak is less than a certain threshold, although it can be determined that the first superposition signal is the echo signal of the first laser sequence sent, it fails to meet the established anti-interference requirements. Therefore, the control module can further increase the interval length and / or the number of intervals of the first time interval, that is, the emission time and / or the number of intervals of the emitted laser signal can be increased, and the accumulation of interference signals can be further avoided so that the signal-to-interference ratio can be improved, thereby improving the anti-interference capability of the laser radar.

[0022] As a possible implementation manner, the control module determines N second sequences and N groups of second time intervals according to the first superimposed signal further includes: when the correlation peak does not exist, adjusting the N first sequences to obtain N first sequences.

[0023] In the embodiment of the present application, when there is no correlation peak between the first sequence and the first superposition signal, the control module cannot determine that the first superposition signal is an echo signal of the laser signal emitted by the first sequence. At this time, the laser signal may be interfered by other laser radars, so the control module can adjust the current first sequence to reduce the influence of the interference signal, thereby improving the anti-interference ability of the laser radar.

[0024] As a possible implementation, the control module determines N second sequences and N groups of second time intervals based on the first superposition signal and further includes: when the value of the main-sidelobe ratio is greater than a second threshold, reducing the interval length and / or number of each group of first time intervals in the N groups of first time intervals to obtain N groups of first time intervals, and the second threshold is greater than the first threshold.

[0025] In an embodiment of the present application, when the value of the main-to-sidelobe ratio is much larger than the second threshold value, the interval length and the number of intervals of the time interval can be reduced. On the premise of ensuring that the anti-interference capability of the laser radar meets the current environment, the processing overhead can be reduced, thereby improving the processing efficiency of the control module and saving processing resources.

[0026] As a possible implementation manner, the control module determines N second sequences and N groups of second time intervals according to the first superimposed signal and further includes: when the signal-to-noise ratio of the first superimposed signal is greater than or equal to the third threshold, adjusting the N first sequences to obtain N first sequences.

[0027] In the embodiment of the present application, when it is not determined that the first superposition signal has a certain similarity with the N first sequences, the control module can determine whether there is a certain signal accumulation in the first superposition signal by determining the signal-to-noise ratio of the first superposition signal. Since the existence of signal accumulation but the absence of correlation peaks may be caused by interference signals in the environment, the control module can improve the anti-interference ability of the laser radar by adjusting the first sequence.

[0028] As a possible implementation manner, the interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

[0029] In the embodiment of the present application, in the process of adjusting the time interval, increasing the interval length and the number of intervals of the time interval improves the anti-interference capability while increasing the processing overhead. When the interval length and the number of intervals of the time interval are increased to a certain extent, continuing to increase the interval length and the number of intervals of the time interval cannot significantly improve the anti-interference capability of the laser radar. Therefore, setting the upper limit of the interval length and the number of intervals of the time interval can not only avoid the endless increase of the interval length and the number of intervals of the time interval to reduce the waste of processing resources, but also improve the processing efficiency.

[0030] The second aspect discloses a laser radar anti-interference method, which is applied to a laser radar anti-interference device. The method may include: determining N first sequences and N groups of first time intervals, where N is an integer greater than or equal to 1; transmitting N first laser signals according to the N first sequences and the N groups of first time intervals; receiving N second laser signals, converting the N second laser signals into electrical signals to obtain N first electrical signals; superimposing the N first electrical signals to obtain a first superimposed signal; and determining N second sequences and N groups of second time intervals according to the first superimposed signal.

[0031] In an embodiment of the present application, the first time interval can determine the sending time of the corresponding first sequence, and the interval length of the N groups of first time intervals is a random time length. Therefore, the time length of the sending time of the corresponding signals of the N first sequences is random. After receiving N second laser signals, the corresponding electrical signals can be superimposed according to the N groups of first time intervals to obtain a first superimposed signal. Compared with the directly received signal, the amplitude of the superimposed first superimposed signal will be greatly improved, which can improve the signal-to-noise ratio. At the same time, the sending time of the laser signal is random, which can avoid the accumulation of noise. Therefore, the noise points in the point cloud map of the laser radar system can be reduced, and the anti-interference ability of the laser radar can be improved.

[0032] As a possible implementation, the method may further include: generating N second electrical signals according to the N first sequences and the N groups of first time intervals; and transmitting N first laser signals according to the N first sequences and the N groups of first time intervals includes: transmitting N first laser signals according to the N second electrical signals.

[0033] In the embodiment of the present application, since after determining the first sequence and the first time interval, the first sequence is consistent with the sequence of the emitted first laser signal, the consistency of the first sequence and the sequence of the laser signal can be ensured. In addition, the length of the time interval for sending N first laser signals can be determined by N groups of first time intervals, and the randomness of the sending time can be achieved. When superimposing the signal, the accumulation of interference signals of fixed frequency can be avoided, thereby improving the signal-to-interference ratio of the superimposed signal.

[0034] As a possible implementation manner, when the N first sequences are the same sequence, superimposing the N first electrical signals to obtain a first superimposed signal includes: superimposing the N first electrical signals according to the N groups of first time intervals to obtain a second superimposed signal; and filtering the second superimposed signal according to the N first sequences to obtain a first superimposed signal.

[0035] In the embodiment of the present application, the N first sequences are the same sequence, that is, the sequence of the N laser signals sent is the same laser sequence, but the N groups of first time intervals are random, and the time used for sending is different, so the corresponding electrical signals can be superimposed to obtain a second superimposed signal, and the signal amplitude of the superimposed signal is greatly improved after accumulation. At the same time, the sending time of the laser signal is random, so the accumulation of interference signals of fixed frequency can be reduced. Furthermore, since the second superimposed signal is formed by the superposition of corresponding signals of the same sequence, the superimposed signal can be directly filtered. After filtering, not only can signal interference be reduced and the anti-interference performance of the laser radar be improved, but also the number of filtering times can be reduced and the internal structure of the control module can be simplified.

[0036] As a possible implementation manner, when the N first sequences are different sequences, superimposing the N first electrical signals to obtain a first superimposed signal includes: filtering the N first electrical signals according to the N first sequences to obtain N filtered signals; and superimposing the N filtered signals according to the N groups of first time intervals to obtain a first superimposed signal.

[0037] In the embodiment of the present application, the N first sequences are different sequences, that is, the sequences of the N laser signals sent are different laser sequences. Since the first superposition signal is a superposition signal of signals corresponding to different sequences, the probability of this laser radar and other laser radars using the same or similar sequences can be reduced to avoid interference caused by multiple laser radars using the same or similar sequences, thereby further improving the anti-interference ability of the laser radar. Due to the different sequences, the signals corresponding to different sequences can be filtered first, and then superimposed to form the first superposition signal, which can reduce the impact of interference signals, thereby improving the anti-interference performance of the laser radar.

[0038] As a possible implementation, the method may further include: receiving N third laser signals, transmitting N fourth laser signals, and reflecting N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the spectrometer, and the third laser signal includes the fourth laser signal and the fifth laser signal; receiving N sixth laser signals, converting the N sixth laser signals into electrical signals to obtain N third electrical signals, wherein the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; filtering the second superimposed signal according to the N first sequences to obtain the first superimposed signal includes: adjusting the filter coefficient of the filter according to the N third electrical signals; filtering the second superimposed signal according to the N first sequences to obtain the first superimposed signal.

[0039] In an embodiment of the present application, after emitting a laser signal, the emitted laser signal can be reflected and transmitted to form two laser signals with the same sequence. Among them, one laser signal can be emitted to the detected object, and the other laser signal can be directly emitted back. After receiving the signal emitted directly back, the filter coefficient of the filter can be adjusted, and the filter coefficient can correspond to the sequence actually sent. At this time, by adjusting the filter coefficient, the problem of reduced detection performance of the laser radar caused by internal interference of the laser radar can be avoided, thereby improving the anti-interference ability of the laser radar.

[0040] As a possible implementation, the method may further include: receiving N third laser signals, transmitting N fourth laser signals, and reflecting N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes the fourth laser signal and the fifth laser signal; receiving N sixth laser signals, converting the N sixth laser signals into electrical signals to obtain N fourth electrical signals, wherein the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; filtering the N first electrical signals according to the N first sequences to obtain N filtered signals includes: adjusting the filter coefficient of the filter according to the N fourth electrical signals; filtering the second superposition signal according to the N first sequences to obtain N filtered signals.

[0041] In an embodiment of the present application, after emitting a laser signal, the emitted laser signal can be reflected and transmitted to form two laser signals with the same sequence. Among them, one laser signal can be emitted to the detected object, and the other laser signal can be directly emitted back. After receiving the signal emitted directly back, the filter coefficient of the filter can be adjusted, and the filter coefficient can correspond to the sequence actually sent. At this time, by adjusting the filter coefficient, the problem of reduced detection performance of the laser radar caused by internal interference of the laser radar can be avoided, thereby improving the anti-interference ability of the laser radar.

[0042] As a possible implementation, determining N second sequences and N groups of second time intervals based on the first superimposed signal includes: when there is a correlation peak between the N first sequences and the first superimposed signal, and the value of the main-sidelobe ratio of the correlation peak is greater than a first threshold, determining the N first sequences as the N second sequences, and determining the N groups of first time intervals as the N groups of second time intervals.

[0043] In an embodiment of the present application, a cross-correlation operation can be performed on the first sequence and the first superposition signal. When a correlation peak exists in the result of the cross-correlation, it can be explained that the first superposition signal is an echo signal of the laser signal emitted by the corresponding first sequence. Further, when the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold value, it can be determined that the interference of the received echo signal is small and can meet the detection requirements of the laser radar. When the detection requirements of the laser radar can be met, it can be determined that the N first sequences and N groups of first time intervals are suitable for the current environment, that is, the N first sequences and N groups of first time intervals can be determined as N second sequences and N groups of second time intervals. At this time, the current N first sequences and the current N groups of first time intervals are no longer adjusted, thereby reducing processing overhead and improving processing efficiency.

[0044] As a possible implementation, determining N second sequences and N groups of second time intervals based on the first superposition signal also includes: when the correlation peak exists and the value of the main-sidelobe ratio is less than or equal to the first threshold, increasing the interval length and / or the number of intervals included in each group of first time intervals in the N groups of first time intervals to obtain N groups of first time intervals.

[0045] In an embodiment of the present application, when there is a correlation peak in the result of the cross-correlation operation between the first sequence and the first superposition signal, it means that there is a certain degree of similarity between the N first sequences and the first superposition signal, and it can be determined that the first superposition signal is the echo signal of the current N first sequences. Further, when the value of the main-sidelobe ratio of the correlation peak is less than a certain threshold, although it can be determined that the first superposition signal is the echo signal of the first laser sequence sent, it fails to meet the established anti-interference requirements. Therefore, the interval length and / or the number of intervals of the first time interval can be further increased, that is, the emission time and / or the number of intervals of the emitted laser signal can be increased, and the accumulation of interference signals can be further avoided, so that the signal-to-interference ratio can be improved, thereby improving the anti-interference capability of the laser radar.

[0046] As a possible implementation manner, determining N second sequences and N groups of second time intervals according to the first superimposed signal further includes: when the correlation peak does not exist, adjusting the N first sequences to obtain N first sequences.

[0047] In the embodiment of the present application, when there is no correlation peak between the first sequence and the first superposition signal, it cannot be determined that the first superposition signal is an echo signal of the laser signal emitted by the first sequence. At this time, the laser signal may be interfered by other laser radars, so the current first sequence can be adjusted to reduce the influence of the interference signal, thereby improving the anti-interference ability of the laser radar.

[0048] As a possible implementation, determining N second sequences and N groups of second time intervals based on the first superimposed signal also includes: when the value of the main-sidelobe ratio is greater than the second threshold, reducing the interval length and / or number of each group of first time intervals in the N groups of first time intervals to obtain N groups of first time intervals, and the second threshold is greater than the first threshold.

[0049] In an embodiment of the present application, when the value of the main-to-sidelobe ratio is much larger than the second threshold, the interval length and the number of intervals of the time interval can be reduced. While ensuring that the anti-interference capability meets the current environment, the processing overhead can be reduced, thereby improving processing efficiency and saving processing resources.

[0050] As a possible implementation, determining N second sequences and N groups of second time intervals according to the first superimposed signal further includes: when a signal-to-noise ratio of the first superimposed signal is greater than the third threshold, adjusting the N first sequences to obtain N first sequences.

[0051] In the embodiment of the present application, when it is not determined that the first superposition signal has a certain similarity with the N first sequences, it can be determined whether there is a certain signal accumulation in the first superposition signal by determining the signal-to-noise ratio of the first superposition signal. Since the existence of signal accumulation but the absence of correlation peaks may be caused by interference signals in the environment, the anti-interference ability of the laser radar can be improved by adjusting the first sequence.

[0052] As a possible implementation manner, the interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

[0053] In the embodiment of the present application, in the process of adjusting the time interval, increasing the interval length and the number of intervals of the time interval improves the anti-interference capability while increasing the processing overhead. When the interval length and the number of intervals of the time interval are increased to a certain extent, continuing to increase the interval length and the number of intervals of the time interval cannot significantly improve the anti-interference capability of the laser radar. Therefore, setting the upper limit of the interval length and the number of intervals of the time interval can not only avoid the endless increase of the interval length and the number of intervals of the time interval to reduce the waste of processing resources, but also improve the processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a schematic diagram of an application scenario of a laser radar disclosed in an embodiment of the present application;

[0055] Figure 2 is a schematic diagram of a laser pulse disclosed in an embodiment of the present application;

[0056] Figure 3It is a structural schematic diagram of a laser radar anti-interference device disclosed in an embodiment of the present application;

[0057] Figure 4 is a schematic diagram of a signal superposition method disclosed in an embodiment of the present application;

[0058] Figure 5 It is a schematic structural diagram of another laser radar anti-interference device disclosed in an embodiment of the present application;

[0059] Figure 6 This is a schematic diagram of a method flow of a signal anti-interference strategy disclosed in an embodiment of the present application;

[0060] Figure 7 is a schematic diagram of a cross-correlation calculation method disclosed in an embodiment of the present application;

[0061] Figure 8 It is a structural schematic diagram of another laser radar anti-interference device disclosed in an embodiment of the present application;

[0062] Fig. 9 It is a flow chart of a laser radar anti-interference method disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0063] The embodiments of the present application disclose a laser radar anti-interference method and device, which are used to improve the anti-interference capability of the laser radar.

[0064] In order to better understand the laser radar anti-interference method and device disclosed in the embodiment of the present application, the relevant technologies of the embodiment of the present application are first introduced below.

[0065] Laser detection and ranging (LiDAR) systems are widely used in areas such as assisted or autonomous driving, service robots, and industrial automation. In actual application scenarios, there are many sources of interference to LiDAR. Figure 1 , Figure 1 is a schematic diagram of an application scenario of a laser radar disclosed in an embodiment of the application, such as Figure 1 As shown in Figure 1, with the popularity of vehicle-mounted LiDAR, the phenomenon of LiDAR being interfered with is becoming increasingly serious. This will not only affect the ranging performance of the LiDAR system itself, but also affect the performance of other systems. For example, in the Internet of Vehicles, when the LiDAR is interfered with, the advanced driver assistance systems (ADAS) function will also be interfered with.

[0066] LiDAR can be divided into pulsed LiDAR and continuous wave LiDAR according to the laser emission waveform. Figure 2 , Figure 2 is a schematic diagram of a laser pulse. Figure 2 As shown, by adjusting the time interval and amplitude of a group of laser pulses, each laser radar carries specific information. For example, the emitted pulse signal may include two pulses, the amplitudes of the first pulse and the second pulse may be different, and their amplitudes are fixed. The time interval between the two pulses may also be fixed. After receiving the reflected laser signal, the pulse amplitude of the received laser signal and the time interval between the laser pulses may be detected. When the amplitude value of the received laser signal is equal to the amplitude value of the emitted laser signal, and the time interval between the pulses of the received laser signal is also the same as the time interval between the pulses of the emitted laser signal, it can be determined that the received laser signal is the echo signal reflected from the emitted laser signal by the detection object. The echo signal can be understood as a received laser signal that has a certain similarity with the signal characteristics of the emitted signal after detecting the corresponding signal characteristics (for example, the above-mentioned pulse amplitude and the time interval between pulses).

[0067] When the laser radar emits a laser signal to the object being detected, in order to ensure eye safety, the laser emission power needs to be limited, which limits the signal-to-noise ratio of the received echo signal and the ranging capability of the laser radar. Since interference signals have a great impact on the laser radar, how to further improve the anti-interference capability of the laser radar is an urgent problem to be solved.

[0068] See also Figure 3 , Figure 3 Schematic diagram of the structure of a laser radar anti-interference device disclosed in the embodiment of the present application. Figure 3 As shown, the laser radar anti-interference device may include a control module 301, a laser 302 and a detector 303, wherein:

[0069] A control module 301 is used to determine N first sequences and N groups of first time intervals, where N is an integer greater than or equal to 1;

[0070] A laser 302, configured to emit N first laser signals according to N first sequences and N groups of first time intervals;

[0071] The detector 303 is used to receive the N second laser signals and convert the N second laser signals into electrical signals to obtain N first electrical signals;

[0072] The control module 301 is further configured to superimpose N first electrical signals to obtain a first superimposed signal, and determine N second sequences and N groups of second time intervals according to the first superimposed signal.

[0073] When it is necessary to detect the surrounding environment by laser radar, the control module 301 can determine N first sequences and N groups of first time intervals. The control module 301 can generate N first sequences by generating a random sequence, or select N first sequences from a stored sequence, or adjust the first sequence used last time to obtain N first sequences, or continue to use the first sequence used last time as the current N first sequences. It should be understood that the above is an example of how to determine the first sequence, and does not limit its specific determination method. Among them, the first sequence can be a sequence representing a pulsed laser signal. N is an integer greater than or equal to 1. In one case, each of the N first sequences can be the same. In another case, each of the N first sequences can be different, or partially the same and partially different. A first sequence can include a non-zero value, such as "1"; it can also include multiple non-zero values, such as "10111001".

[0074] The control module 301 can determine the N groups of first time intervals by generating random numbers, or can determine the N groups of first time intervals according to a preset random sequence, or can adjust the first time interval used last time to obtain the N groups of first time intervals, or can continue to use the first time interval used last time as the current N groups of first time intervals. It should be understood that the above is an example of generating N groups of random first time intervals, and does not limit the specific method of generating random time intervals. Among them, the first time interval represents the time interval between two groups of laser signals. The N groups of first time intervals can be time intervals of random time length. Each group of first time intervals in the N groups of first time intervals can be the same, or different, or partially the same and partially different.

[0075] After the control module 301 determines the N first sequences and the N groups of first time intervals, the N first sequences and the N groups of first time intervals can be sent to the laser 302. After the laser 302 receives the N first sequences and the N groups of first time intervals, the N first laser signals can be emitted according to the N first sequences and the N groups of first time intervals. The first laser signal can be a pulsed laser signal, wherein the sequence of the first laser signal can correspond to the first sequence. That is, it can be understood that the sequence of the N first laser signals can be determined by the N first sequences, and the two-to-two adjacent emission times of the N first laser signals can be determined by the N groups of first time intervals. For example, the sequence of the first first laser signal emitted by the laser 302 is consistent with the first first sequence (such as this first sequence is "1010", and the sequence of the corresponding first laser signal is also "1010"), the sequence of the second first laser signal is consistent with the second first sequence, ..., the sequence of the Nth first laser signal is consistent with the Nth first sequence. The laser 302 can calculate the starting time of the emission of each first laser signal according to the N groups of first time intervals. For example, a set of first time intervals may represent the time intervals between two first laser signals emitted one after the other. For example, the sequence of the first first laser signal is "1010", and the sequence of the second first laser signal is "0101", and the first time interval may represent the interval length between the first sequence "1" in the emission of "1010" and the first sequence "0" in the emission of "0101". When the laser determines the start time of emitting N first laser signals through the N-1th first time interval, further, the end time of emitting N first laser signals may be determined through the Nth first time interval.

[0076] When the laser 302 emits a laser signal, the detector 303 may detect a reflected signal of the laser signal emitted by the laser 302. Therefore, after the laser 302 emits N first laser signals according to N first sequences and N groups of first time intervals, the detector 303 may receive N second laser signals. The second laser signal may include a laser signal reflected by the first laser signal through the detection object, and may also include an interference signal, and may also include an interference signal and a laser signal reflected by the first laser signal through the detection object. Among them, the interference signal may include other laser signals that are not the first laser signal that the detector 303 can receive and are reflected by the detection object. Afterwards, the detector 303 may convert the N second laser signals into electrical signals to obtain N first electrical signals, and may send the N first electrical signals to the control module 301.

[0077] After the control module 301 receives the N first electrical signals from the detector 303, the N first electrical signals may be superimposed to obtain a first superimposed signal. Figure 4 , Figure 4A schematic diagram of a signal superposition method disclosed in an embodiment of the present application. Figure 4 As shown, the interval length of the first time interval of group 1 is T 1 , the interval length of the first time interval of the second group is T 2 , ..., the interval length of the first time interval of the Nth group is T N The control module 301 can correspondingly superimpose T 1 , T 2 ,……,T N N first electrical signals at corresponding time intervals. Figure 4 As shown in (a) of FIG. 1 , the control module 301 can detect a sequence of N first electrical signals. The control module 301 can detect a sequence of N first electrical signals according to the start time and the N groups of first time intervals T 1 , T 2 ,……,T N , superimpose N first electrical signals to obtain a first superimposed signal. Figure 4 As shown in (b) in FIG. 3 , the signal after reflection may contain interference signals, that is, the received N second laser signals may be the laser signals reflected by the N first laser signals from the detection object and the N interference signals. That is, there may be interference in the N first electrical signals received by the control module 301. The control module 301 can superimpose the corresponding N first electrical signals to obtain a superimposed signal. The superimposed signal obtained by the control module 301 may contain interference, but due to the 1 , T 2 The time length from TN to TN is random, which can avoid the accumulation of interference signals to a certain extent. In addition, compared with the signal without superposition, the amplitude of the first sequence in the superimposed signal will increase, so a larger signal-to-interference ratio can be generated, thereby improving the anti-interference ability of the laser radar. It should be noted that the control module 301 can perform filtering in the process of superimposing N first electrical signals, and the signal after filtering and superposition is the first superimposed signal.

[0078] After the control module 301 obtains the first superposition signal, a cross-correlation operation can be performed between the obtained first superposition signal and the known first sequence to determine whether the first superposition signal is an echo signal reflected from the laser signal emitted by the first sequence. The control module 301 can determine N second sequences and N groups of second time intervals according to whether the echo signal contains the laser emission signal.

[0079] See also Figure 5 , Figure 5 : is a schematic diagram of the structure of another laser radar anti-interference device disclosed in the embodiment of the present application. Figure 5 The laser radar anti-interference device shown is composed of Figure 3The laser radar anti-interference device shown is optimized. Figure 5 As shown, the laser radar anti-interference device may include a control module 501 , a laser 502 and a detector 503 .

[0080] A detailed description can be found in Figure 3 The corresponding description.

[0081] In one embodiment, the laser radar anti-interference device may further include a signal generator 504, wherein:

[0082] A signal generator 504, configured to generate N second electrical signals according to the N first sequences and the N groups of first time intervals;

[0083] The laser 502 transmits N first laser signals according to the N first sequences and the N groups of first time intervals, including:

[0084] The laser 502 emits N first laser signals according to the N second electrical signals.

[0085] The signal generator 504 can be coupled to the control module 501 and the laser 502 respectively. The control module 501 can send the determined N first sequences and N groups of first time intervals to the signal generator 504. After receiving the N first sequences and the N groups of first time intervals, the signal generator 504 can generate N second electrical signals according to the N first sequences and the N groups of first time intervals. That is, the signal generator 504 can determine the sequence of the N second electrical signals according to the N first sequences, and can determine the time intervals between the N second electrical signals according to the N groups of first time intervals. The sequence of each signal in the N second electrical signals can be determined by the N first sequences, and the start time of the emission corresponding to each sequence in the N second electrical signals can be determined by the N groups of time intervals. For example, the sequence of the first second electrical signal generated by the signal generator 504 is the same as the first first sequence, and the sequence of the second second electrical signal is the same as the second first sequence. In addition, the time interval between the start time of the first second electrical signal emitted by the signal generator 504 and the start time of the second second electrical signal is the first group of first time intervals, ..., the time interval between the start time of the N-1th second electrical signal and the start time of the Nth second electrical signal is the N-1th group of first time intervals, and the time interval between the start time and the end time of the Nth second electrical signal is the Nth group of first time intervals. Further, the laser 502 can emit N first laser signals according to the N second electrical signals, which can be understood as the sequence of the N first laser signals being the same as the sequence of the N second electrical signals, and the time interval between two adjacent first laser signals being the same as the time interval between two corresponding adjacent second electrical signals, and the time interval between the start time and the end time of the last first laser signal being the same as the time interval between the start time and the end time of the last second electrical signal.

[0086] In one embodiment, when the N first sequences are the same sequence, the control module 501 superimposes the N first electrical signals to obtain a first superimposed signal, including:

[0087] Superimposing N first electrical signals according to N groups of first time intervals to obtain a second superimposed signal;

[0088] The second superimposed signal is filtered according to the N first sequences to obtain a first superimposed signal.

[0089] After the detector 503 receives the N second laser signals, it can convert the N second laser signals into electrical signals to obtain N first electrical signals. Figure 3. The detector 503 may send N first electrical signals to the control module 501. The control module 501 may include a filter 5011. When the N first sequences are the same sequence, after the control module 501 receives the N first electrical signals, the N first electrical signals may be superimposed according to the N groups of first time intervals to obtain a second superimposed signal, and then the second superimposed signal may be filtered according to the N first sequences to obtain the first superimposed signal. The specific superposition method can be referred to above Figure 4 and Figure 5 The corresponding method is not elaborated here. The control module 501 can determine the filter coefficient of the filter according to the first sequence, and then filter the second superimposed signal through the filter to obtain the first superimposed signal. The control module 501 can first determine N first sequences, and determine the filter coefficient of the filter according to the first sequence. For example, when the first sequence is the same sequence, assuming that this sequence is "1010", the control module 501 can set the filter coefficient to "1010". Of course, other filter coefficients can also be set as needed. After filtering, the interference signal and noise can be removed, so that the signal-to-noise ratio of the superimposed signal can be further improved, and the anti-interference ability of the laser radar can be improved.

[0090] It should be understood that the control module 501 may include a decoder 5013 , and the control module 501 superimposes N first electrical signals to obtain a first superimposed signal, which may be completed by the decoder 5013 .

[0091] In one embodiment, the laser radar anti-interference device may further include a spectroscope 505, and the control module 501 may include a filter 5011, wherein:

[0092] A beam splitter 505 is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, where the third laser signal is a laser signal transmitted from the first laser signal to the beam splitter, and the third laser signal includes the fourth laser signal and the fifth laser signal;

[0093] The detector 503 is further used to receive N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N third electrical signals, where the sixth laser signal is the laser signal transmitted to the detector by the fifth laser signal;

[0094] The control module 501 filters the second superimposed signal according to the N first sequences to obtain the first superimposed signal including:

[0095] The control module 501 adjusts the filter coefficient of the filter 5011 according to the N third electrical signals;

[0096] The filter 5011 filters the second superimposed signal according to the N first sequences to obtain a first superimposed signal.

[0097] The laser 502 can send N first laser signals to the spectroscope 505, and the spectroscope 505 can receive N third laser signals. After receiving the N third laser signals, the spectroscope 505 can transmit N fourth laser signals and reflect N fifth laser signals. The third laser signal can be a laser signal transmitted from the first laser signal to the spectroscope 505. The third laser signal can include a fourth laser signal and a fifth laser signal, that is, it can be understood that the spectroscope 505 can transmit and reflect the N third laser signals to obtain N fourth laser signals and N fifth laser signals. After that, the spectroscope 505 can emit N fourth laser signals to the detection object, and can directly send N fifth laser signals to the detector 503. After that, the detector 503 can receive N second laser signals, convert the N second laser signals into electrical signals, and obtain N first electrical signals. The detector 503 can also receive N sixth laser signals, and the N sixth laser signals can be laser signals transmitted from the N fifth laser signals to the detector 503. Then the detector 503 can convert the N sixth laser signals into electrical signals to obtain N third electrical signals.

[0098] After the control module 501 receives the N third electrical signals from the detector 503, the filter coefficient of the filter 5011 can be determined based on the N third electrical signals. The control module 501 can filter the superposition signal of the N first electrical signals (i.e., the second superposition signal) to obtain the first superposition signal. The control module 501 can determine the filter coefficient based on the N third electrical signals. The control module 501 can adjust the filter coefficient of the filter 5011 based on the same sequence corresponding to the N third electrical signals. After the filter coefficient is determined, the control module 501 can filter the second superposition signal. The detailed filtering method can refer to the above Figure 7 The relevant description in the above description will not be repeated here. It should be understood that after reflection and transmission by the spectroscope 505, the fifth laser signal can be directly sent to the detector 503 instead of being sent to the detection object, and the detector 503 can directly receive N sixth laser signals, and can determine N third electrical signals according to the laser signal emitted by the laser 502, and the control module 501 can determine the sequence of the N first laser signals emitted according to the N third electrical signals. In this case, even if interference occurs inside the control module 501, the signal generator 504 and the laser 502, since the coefficients of the filter are readjusted according to the N third electrical signals, the control module 501 can also increase the probability of correctly superimposing and filtering the N first electrical signals, thereby improving the anti-interference ability of the laser radar device.

[0099] It should be understood that, generally, the detector 501 should receive the sixth laser signal first and then the second laser signal, but special circumstances are not excluded. Therefore, the order in which the detector 504 receives the sixth laser signal and the second laser signal is not limited here.

[0100] In one embodiment, the control module 501 determines N second sequences and N groups of second time intervals according to the first superposition signal, including:

[0101] When there is a correlation peak between the N first sequences and the first superimposed signal, and the main lobe to side lobe ratio of the correlation peak is greater than a first threshold, the N first sequences are determined as N second sequences, and the N groups of first time intervals are determined as N groups of second time intervals.

[0102] In one embodiment, the control module 501 determines the N second sequences and the N groups of second time intervals according to the first superimposed signal further includes:

[0103] When there is a correlation peak and the value of the main-sidelobe ratio is less than or equal to the first threshold, the interval length and / or the number of intervals included in each group of N groups of first time intervals is increased to obtain N groups of new first time intervals.

[0104] In one embodiment, the control module 501 determines the N second sequences and the N groups of second time intervals according to the first superimposed signal further includes:

[0105] When the value of the main-sidelobe ratio is greater than the second threshold, the interval length and / or the number of intervals of each group of N groups of first time intervals are reduced to obtain N groups of new first time intervals, and the second threshold is greater than the first threshold.

[0106] In one embodiment, the control module 501 determines the N second sequences and the N groups of second time intervals according to the first superimposed signal further includes:

[0107] When there is no correlation peak, the N first sequences are adjusted to obtain new N first sequences.

[0108] In one embodiment, the control module 501 determines the N second sequences and the N groups of second time intervals according to the first superimposed signal further includes:

[0109] When the signal-to-noise ratio of the first superimposed signal is greater than a third threshold, the N first sequences are adjusted to obtain N first sequences.

[0110] See also Figure 6 , Figure 6 Schematic diagram of a signal anti-interference strategy disclosed in the embodiment of the present application. Figure 6As shown, the control module 501 can first determine the current N first sequences and the current N groups of first time intervals. After the control module 501 receives the N first electrical signals (and can also receive the N third electrical signals), it can superimpose and filter the N first electrical signals to obtain a first superimposed signal. Then the control module 501 can determine whether there is a correlation peak between the first superimposed signal and the current first sequence. When it is determined that there is a correlation peak, the control module 501 can continue to determine whether the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold. When it is determined that the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold, the control module 501 can determine N second sequences and N groups of second time intervals. Further, the control module 501 can determine the first superimposed signal as a target echo signal and output the target echo signal. In one case, when it is determined that the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold, the control module 501 can determine the current N first sequences as N second sequences, determine the current N groups of first time intervals as N groups of second time intervals, and output the target echo signal. In another case, when it is determined that the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold, the control module 501 may continue to determine whether the value of the main-sidelobe ratio of the correlation peak is greater than the second threshold. When it is determined that the value of the main-sidelobe ratio of the correlation peak is less than or equal to the second threshold, the control module 501 may determine the current N first sequences as N second sequences, determine the current N groups of first time intervals as N groups of second time intervals, and output the target echo signal. The second threshold is greater than the first threshold.

[0111] When it is determined that the value of the main-sidelobe ratio of the correlation peak is less than or equal to the first threshold, the control module 501 can adjust the current N groups of first time intervals. When it is determined that the value of the main-sidelobe ratio of the correlation peak is greater than the second threshold, the control module 501 can adjust the current N groups of first time intervals. When it is determined that there is no correlation peak, the control module 501 can continue to determine whether the signal-to-noise ratio of the first superimposed signal is greater than the third threshold. When it is determined that the signal-to-noise ratio is greater than the third threshold, the control module 501 can adjust the current N first sequences. When it is determined that the signal-to-noise ratio is less than or equal to the third threshold, it can indicate that the second laser signal does not include the echo signal of the first laser signal, and the target echo signal may not be output at this time. The correlation peak may be a correlation peak obtained by the control module 501 cross-correlating the current N first sequences with the first superimposed signal. For one possible case, please refer to Figure 7 , Figure 7 Schematic diagram of a cross-correlation calculation method disclosed in the embodiment of the present application. Figure 7 (a) is the first superposition signal, and the control module 501 can perform a cross-correlation operation on the first superposition signal and the N first sequences. Figure 7It can be seen from (b) in that the result of the cross-correlation operation may have a correlation peak. When there is a correlation peak between the current first sequence and the first superposition signal, it can be reflected that the first sequence and the first superposition signal are sufficiently similar, and the control module 501 can determine that the first superposition signal is the echo signal corresponding to the N first sequences. Further, when the value of the main-sidelobe ratio of the correlation peak is greater than the first threshold, it can be indicated that the echo signal can meet the requirements of the system, and the first superposition signal can be output as the selected target echo signal.

[0112] The first threshold value may be variable. For example, the control module 501 may adjust the first threshold value according to the signal-to-noise ratio of the first superimposed signal, or may adjust the first threshold value according to the value of the main-sidelobe ratio of the correlation peak, or may be set according to the requirements of the system, or may be set by other methods. The first threshold value may also be fixed, that is, it may be a pre-set value. It should be understood that the above is only an example of a method for determining the first threshold value and does not constitute a limitation.

[0113] The second threshold value may be variable. For example, the control module 501 may adjust the second threshold value according to the absolute value of the difference between the main-sidelobe ratio of the correlation peak corresponding to the last first superposition signal and the current first superposition signal. When the absolute value of the difference is greater than the sixth threshold value, it indicates that the values ​​of the main-sidelobe ratio of their correlation peaks differ greatly, and the control module 501 may increase the second threshold value. When the absolute value of the difference is less than or equal to the sixth threshold value, it indicates that the values ​​of the main-sidelobe ratio of their corresponding correlation peaks differ slightly, and the control module 501 may reduce the second threshold value or keep the second threshold value unchanged. The second threshold value may also be fixed.

[0114] The third threshold may be variable or fixed. The control module 501 may set the third threshold to a fixed value, or adjust the third threshold according to the signal-to-noise ratio of the first superimposed signal or the main-sidelobe ratio of the correlation peak.

[0115] Before determining whether there is a correlation peak, the control module 501 may first perform a dynamic threshold detection on the first superimposed signal. The control module 501 may determine a threshold value, and then determine whether the amplitude value of the first superimposed signal is greater than the threshold value. When it is determined that the amplitude value is greater than the threshold value, it may continue to determine whether there is a correlation peak; when it is determined that the amplitude value is less than or equal to the threshold value, the first superimposed signal may be discarded. This threshold value may be dynamically changed. The dynamic threshold value may be determined according to the channel conditions. For example, when the signal-to-noise ratio is less than or equal to the seventh threshold value, the value of the threshold value may be reduced, and when the signal-to-noise ratio is greater than the seventh threshold value, the value of the threshold value may be increased. This threshold value may also be determined according to the amplitude of other received signals. It should be understood that the above is only an example of the determination of the dynamic threshold, and does not constitute a limitation on the specific determination method.

[0116] When it is determined that the value of the main-sidelobe ratio of the correlation peak is less than or equal to the first threshold value, the control module 501 can increase the interval length and / or the number of intervals of the current N groups of first time intervals to determine a new N groups of first time intervals. That is, it can be understood that the time interval between two adjacent emitted first laser signals can be increased and / or the number of transmitted first laser signals can be increased (i.e., the size of N is increased). In one case, the interval length and / or the number of intervals increased each time can be the same. The control module 501 can increase the interval length and / or the number of intervals of the first time interval according to the step length. The control module 501 can pre-set the step length a of the interval length and the step length b of the interval number, and both a and b are greater than zero. Assuming that one of the current N groups of first time intervals has an interval length of a1 and an interval number of b1, when it is necessary to increase this group of first time intervals, the interval length of a new group of time intervals of the group of first time intervals may be a2, and the interval number may be b2. It should be understood that the interval length and interval number of a new group of first time intervals corresponding to the group of first time intervals may be a2=a1+a, b2=b1, or a2=a1, b2=b1+b, or a2=a1+a, b2=b1+b. In another case, the interval length and / or interval number increased each time may be different. The control module 501 may increase the interval length and / or interval number of the time interval according to the absolute value of the difference between the main-sidelobe ratio value of the current correlation peak and the first threshold. When the absolute value of the difference between the first threshold and the main-sidelobe ratio value of the correlation peak is large, the amplitude of the increase of the interval length and / or interval number of the first time interval by the control module 501 may be large. For example, an increasing linear function (such as y=x, x is the absolute value of the difference between the first threshold and the main sidelobe ratio of the correlation peak, and y is the interval length or number of intervals for increasing the first time interval) or a quadratic function y=x can be set. 2 , where x is greater than zero), etc. The control module 501 may also increase the interval length and / or the number of intervals of the first time interval in other ways, and the specific increase method is not limited here. Increasing the interval length of the first time interval can reduce the probability of accumulation of interference signals during the superposition process, and increasing the number of intervals of the first time interval can increase the amplitude of the superposition signal, thereby increasing the signal-to-noise ratio of the first superposition signal, and further improving the anti-interference ability of the laser radar device.

[0117] When it is determined that the value of the main-sidelobe ratio of the correlation peak is greater than the second threshold value, the control module 501 can reduce the interval length and / or the number of intervals of each group of first time intervals in the current N groups of first time intervals to obtain new N groups of first time intervals. That is, it can be understood that the time interval between two adjacent emitted first laser signals can be reduced and / or the number of transmitted first laser signals can be reduced (i.e., the size of N is reduced). In one case, the interval length and / or the number of intervals reduced each time can be the same. The control module 501 can reduce the interval length and / or the number of intervals of the first time interval according to the step length. The control module 501 can pre-set the step length a3 of the interval length and the step length b3 of the interval number, and both a3 and b3 are greater than zero. Assuming that there is a group of first time intervals in the current N groups of first time intervals with an interval length of a1 and an interval number of b1, when it is necessary to reduce this group of first time intervals, the interval length of a new group of time intervals corresponding to the group of first time intervals can be a2, and the interval number can be b2. It should be understood that the interval length and the number of intervals of a new group of first time intervals corresponding to the group of first time intervals may be a2=a1-a3, b2=b1, or a2=a1, b2=b1-b3, or a2=a1-a3, b2=b1-b3. In another case, the interval length and / or the number of intervals reduced each time may be different. The control module 501 may also reduce the interval length and / or the number of intervals of the current N first time intervals according to the absolute value of the difference between the second threshold and the value of the main-sidelobe ratio of the correlation peak. The greater the absolute value of the difference, the greater the reduction. For example, a function may be set (e.g., y=x, x is the absolute value of the difference between the second threshold and the value of the main-sidelobe ratio of the correlation peak, and y is the interval length or the number of intervals of the first time interval to reduce the interval length and / or the number of intervals of the time interval. The interval length and / or the number of intervals of the current N first time intervals may also be reduced in other ways. Since the control module 501 may continuously increase the interval length and / or the number of intervals of the N first time intervals, even if the interval length and / or the number of intervals of the current N first time intervals are further increased, the effect of the output echo signal may not be significantly improved. Therefore, reducing the excessively long time intervals and / or the excessive number of intervals of the first time intervals can improve processing efficiency and reduce the waste of processing resources.

[0118] When it is determined that there is no correlation peak and the signal-to-noise ratio of the first superposition signal is greater than the third threshold, the control module 501 can adjust the current N first sequences to obtain new N first sequences. The control module 501 can adjust the N first sequences so that the new N first sequences are different from the unadjusted first sequences, and can also increase or decrease the length of the current sequence. For example, when the current N first sequences are the same first sequence, and the first sequence is 10011010, it can be determined that the new first sequence is 11001011, or 100110101011, or 100110. It should be understood that when there is no correlation peak, the first superposition signal may also be a certain echo signal received, but due to external interference signals or other factors, the control module 501 may not be able to determine that this signal is an echo signal. Therefore, it can be determined by the signal-to-noise ratio whether there is a certain signal accumulation in the first superposition signal, that is, whether the signal-to-noise ratio of the first superposition signal is greater than the third threshold. When it is judged to be greater than the third threshold, it can be indicated that there is a certain signal accumulation. The control module 501 adjusts the N first sequences so that the signal-to-noise ratio of the first superposition signal obtained next time can be improved by changing the sequence. When it is judged to be less than or equal to the second threshold, it can be indicated that there is no signal accumulation in the first superposition signal, and the target echo signal can be output. When the surrounding laser radar uses the same or similar sequence to detect the surrounding environment, it may interfere with the detection performance of the laser radar device. At this time, the control module 501 can adjust the N first sequences to make the sequence used by the laser radar device different from that of the surrounding laser radar devices, thereby improving the anti-interference ability of the laser radar device.

[0119] In one embodiment, the interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

[0120] The control module 501 can set the fourth threshold and the fifth threshold so that the interval length included in the above-mentioned N groups of second time intervals is less than or equal to the fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to the fifth threshold. Among them, the fourth threshold and / or the fifth threshold can be a fixed value or a variable value. In the case where the fourth threshold and / or the fifth threshold are variable values, the control module 501 can adjust their values ​​according to the received signal quality, channel interference, etc. The specific method for determining the fourth threshold and the fifth threshold is not limited here. When the upper limit of the interval length and the number of intervals of the time interval is set, the time interval can be avoided from endlessly increasing, thereby improving the processing efficiency of the laser radar device and preventing the endless consumption of processing resources.

[0121] The control module 501 may further include a coding / decoding control unit 5012, and the step of determining the current N first sequences and the current N groups of first time intervals according to the first superposition signal may be performed by the coding / decoding control unit 5012. The control module 501 may further include a signal selector 5014, Figure 6 The judgment step in the above example can be performed by the signal selector 5014, and the adjustment of the current N first sequences and the current N groups of first time intervals can be completed by the encoding / decoding control unit 5012. Figure 5 As shown, it can be understood that the encoding / decoding control unit 5012 can first determine the current N first sequences and the current N groups of first time intervals. The control module 501 can also include a decoder 5013. In one case, the decoder 5013 can include a filter 5011. After the decoder 5013 receives the N first electrical signals, it can complete the superposition and filtering of the first electrical signal according to the current N groups of first time intervals and the current N first sequences to obtain a first superposition signal. The signal selector 5014 can obtain the first superposition signal from the decoder 5013, and then determine the N second sequences and N groups of second time intervals according to the first superposition signal. For a detailed description, please refer to the above Figure 6 The corresponding description.

[0122] It should be understood that the current N first sequences and the current N groups of first time intervals determined by the above-mentioned control module 501 are the N first sequences and N groups of first time intervals used for this cycle, and the determined new N first sequences and new N groups of first time intervals are the N first sequences and N groups of first time intervals used for the next cycle. The N second sequences and N groups of second time intervals are the final results obtained after one or more cycles, and are the best sequences and time intervals that can be used by the device in the current environment, and have higher anti-interference capabilities. However, it is only applicable to the current environment. When the environment changes, the anti-interference capabilities of the determined N second sequences and N groups of second time intervals may change. In one possible case, Figure 6 As shown, when the environment changes, the N second sequences and N groups of second time intervals determined in this cycle can be used as the N first sequences and N groups of first time intervals determined for the first time in the next cycle. After the cycle, the next N second sequences and N groups of second time intervals can be determined.

[0123] See also Figure 8 , Figure 8 is a schematic diagram of the structure of another laser radar anti-interference device disclosed in the embodiment of the present application. Figure 8 The laser radar anti-interference device shown is composed of Figure 3 The laser radar anti-interference device shown is optimized. Figure 8As shown, the laser radar anti-interference device may include a control module 801, a laser 802 and a detector 803, wherein:

[0124] A detailed description can be found in Figure 3 and Figure 5 The corresponding description.

[0125] In one embodiment, the laser radar anti-interference device may further include a signal generator 804, wherein:

[0126] A signal generator 804 is used to generate N second electrical signals according to the N first sequences and the N groups of first time intervals;

[0127] The laser 802 transmits N first laser signals according to the N first sequences and the N groups of first time intervals, including:

[0128] The laser 802 emits N first laser signals according to the N second electrical signals.

[0129] For detailed description, please refer to Figure 3 and Figure 5 The corresponding description.

[0130] In one embodiment, when the N first sequences are different sequences, the control module 801 superimposes the N first electrical signals to obtain a first superimposed signal, including:

[0131] Filtering the N first electrical signals according to the N first sequences to obtain N filtered signals;

[0132] N filtered signals are superimposed according to N groups of first time intervals to obtain a first superimposed signal.

[0133] After the detector 801 receives N second laser signals, it can convert the N second laser signals into electrical signals to obtain N first electrical signals. The detector 803 can send the N first electrical signals to the control module 801. The control module 801 may include a filter 8011. When the N first sequences are different sequences, the control module 801 can first filter the N first electrical signals according to the N first sequences to obtain N filtered signals, and then superimpose the N filtered signals according to N groups of first time intervals to obtain a first superimposed signal. That is, it can be understood that the coefficients of N different filters 8011 can be determined first according to N different first sequences, and then the N first electrical signals can be respectively input into the filters 8011 with N corresponding filter coefficients for filtering to obtain N filtered signals. A detailed description of filtering can be referred to. Figure 7Corresponding to the relevant description, it should be noted that at this time, the number of filters 8011 can be one or more, and the filter can determine one or more filter coefficients accordingly. For example, when the number of filters is 1, the order of the N filter coefficients can be determined according to the order of the N first electrical signals received; when the number of filters is multiple, a filter can be determined for each first electrical signal, and each filter can determine a filter coefficient. Further, the control module 801 can superimpose the N filtered signals to obtain a first superimposed signal. The specific superposition process can refer to the above Figure 4 The relevant description of is not repeated here. When the N first sequences are different sequences, even if the sequence of the interference signal is partially the same as the sequence of the first electrical signal, the control module 801 can avoid the influence caused by the interference by filtering and superposition. Therefore, the anti-interference ability of the laser radar can be improved.

[0134] In one embodiment, the laser radar anti-interference device may further include a spectroscope 805, and the control module 801 may include a filter 8011, wherein:

[0135] A beam splitter 805 is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, where the third laser signal is a laser signal transmitted from the first laser signal to the beam splitter, and the third laser signal includes the fourth laser signal and the fifth laser signal;

[0136] The detector 803 is further used to receive N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N fourth electrical signals, where the sixth laser signal is the laser signal transmitted from the fifth laser signal to the detector 803;

[0137] The control module 801 filters the N first electrical signals according to the N first sequences to obtain N filtered signals including:

[0138] The control module 801 adjusts the filter coefficient of the filter 8011 according to the N fourth electrical signals;

[0139] The filter 8011 filters the second superimposed signal according to the N first sequences to obtain N filtered signals.

[0140] The laser 802 may send N first laser signals to the beam splitter 805, and the beam splitter 805 receives N third laser signals. After receiving the N third laser signals, the beam splitter 805 may transmit N fourth laser signals and reflect N fifth laser signals. For related descriptions, please refer to Figure 5 It should be noted that after the detector 803 receives the N sixth laser signals, it can convert the N sixth laser signals into N fourth electrical signals, and then send the N fourth electrical signals to the control module 801.

[0141] After the control module 801 receives the N fourth electrical signals from the detector 803, it can determine the filter coefficient of the filter 8011 according to the N fourth electrical signals. The control module 801 can filter the N first electrical signals to obtain N filtered signals, and then superimpose the N filtered signals to obtain a first superimposed signal. The control module 801 can first determine whether the received N fourth electrical signals are different sequences or partially different sequences, and then determine the corresponding filter coefficients of the filter 8011 according to the N fourth electrical signals. After the control module 801 determines the filter coefficients, it can further filter and superimpose the N first electrical signals. For a detailed description, please refer to the above Figure 5 Related description.

[0142] It should be understood that the order in which the detector 803 receives the sixth laser signal and the second laser signal is not limited herein.

[0143] In one embodiment, the control module 801 determines N second sequences and N groups of second time intervals according to the first superposition signal, including:

[0144] When there is a correlation peak between the N first sequences and the first superimposed signal, and the main lobe to side lobe ratio of the correlation peak is greater than a first threshold, the N first sequences are determined as N second sequences, and the N groups of first time intervals are determined as N groups of second time intervals.

[0145] In one embodiment, the control module 801 determines the N second sequences and the N groups of second time intervals according to the first superposition signal further includes:

[0146] When there is a correlation peak and the value of the main-sidelobe ratio is less than or equal to the first threshold, the interval length and / or the number of intervals included in each group of N groups of first time intervals is increased to obtain N groups of new first time intervals.

[0147] In one embodiment, the control module 801 determines the N second sequences and the N groups of second time intervals according to the first superposition signal further includes:

[0148] When the value of the main-sidelobe ratio is greater than the second threshold, the interval length and / or the number of intervals of each group of N groups of first time intervals are reduced to obtain N groups of new first time intervals, and the second threshold is greater than the first threshold.

[0149] In one embodiment, the control module 801 determines the N second sequences and the N groups of second time intervals according to the first superposition signal further includes:

[0150] When there is no correlation peak, the N first sequences are adjusted to obtain new N first sequences.

[0151] In one embodiment, the control module 801 determines the N second sequences and the N groups of second time intervals according to the first superposition signal further includes:

[0152] When the signal-to-noise ratio of the first superimposed signal is greater than a third threshold, the N first sequences are adjusted to obtain N first sequences.

[0153] For detailed description, please refer to Figure 8 The relevant description is not repeated here.

[0154] In one embodiment, the interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

[0155] For detailed description, please refer to Figure 5 It should be noted that, before determining whether there is a correlation peak between the N first sequences and the first superposition signal, the control module 801 may first superimpose the N first sequences to obtain a composite sequence of the first sequences. Further, the control module 801 may determine whether there is a correlation peak between the composite sequence of the first sequences and the first superposition signal.

[0156] The control module 801 may further include a coding / decoding control unit 8012, and the step of determining the current N first sequences and the current N groups of first time intervals according to the first superposition signal may be performed by the coding / decoding control unit 8012. The control module 801 may further include a signal selector 8014, Figure 6 The judgment step in the above can be performed by the signal selector 8014, and the adjustment of the current N first sequences and the current N groups of first time intervals can be completed by the encoding / decoding control unit 8012. The control module 801 can also include a decoder 8013, and the decoder 8013 can filter the N first electrical signals and superimpose them to obtain a first superimposed signal. The decoder 8013 can include a filter 8011. For detailed description, please refer to Figure 6 The corresponding description.

[0157] It should be understood that the control module 801 determines the current N first sequences and the current N groups of first time intervals as the N first sequences and N groups of first time intervals used for this cycle, and determines the new N first sequences and the new N groups of first time intervals as the N first sequences and N groups of first time intervals used for the next cycle. The N second sequences and N groups of second time intervals are the final results obtained after one or more cycles, and are the best sequences and time intervals that can be used by the device in the current environment, with high anti-interference capabilities. However, it is only applicable to the current environment. When the environment changes, the anti-interference capabilities of the determined N second sequences and N groups of second time intervals may change. In one possible case, Figure 6As shown, when the environment changes, the N second sequences and N groups of second time intervals determined in this cycle can be used as the N first sequences and N groups of first time intervals determined for the first time in the next cycle. After the cycle, the next N second sequences and N groups of second time intervals can be determined.

[0158] See also Fig. 9 , Fig. 9 Schematic diagram of a laser radar anti-interference method disclosed in the embodiment of the present application. Fig. 9 As shown, the laser radar anti-interference method may include the following steps.

[0159] 901. Determine N first sequences and N groups of first time intervals through a control module.

[0160] Wherein, N is an integer greater than or equal to 1.

[0161] 902. Use a laser to emit N first laser signals according to N first sequences and N groups of first time intervals.

[0162] 903. Receive N second laser signals through a detector, convert the N second laser signals into electrical signals, and obtain N first electrical signals.

[0163] 904. Superimpose N first electrical signals through a control module to obtain a first superimposed signal.

[0164] 905. Determine N second sequences and N groups of second time intervals according to the first superimposed signal through a control module.

[0165] In one embodiment, a signal generator may generate N second electrical signals according to N first sequences and N groups of first time intervals, and then a laser may emit N first laser signals according to the N second electrical signals.

[0166] In one embodiment, when the N first sequences are the same sequence, the control module can superimpose the N first electrical signals according to N groups of first time intervals to obtain a second superimposed signal, and then the control module can filter the second superimposed signal according to the N first sequences to obtain the first superimposed signal.

[0167] In one embodiment, N third laser signals can be received by a spectroscope, N fourth laser signals can be transmitted, and N fifth laser signals can be reflected. The third laser signal can be a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal can include a fourth laser signal and a fifth laser signal. N sixth laser signals can also be received by a detector, and the N sixth laser signals can be converted into electrical signals to obtain N third electrical signals. The sixth laser signal can be a laser signal transmitted from the fifth laser signal to the detector. The filter coefficient of the filter can be adjusted according to the N third electrical signals by a control module, and the second superposition signal can be filtered by a filter according to the N first sequences to obtain a first superposition signal.

[0168] In one embodiment, when the N first sequences are different sequences, the control module can filter the N first electrical signals according to the N first sequences to obtain N filtered signals, and the control module can superimpose the N filtered signals according to N groups of first time intervals to obtain a first superimposed signal.

[0169] In one embodiment, N third laser signals can be received by a spectroscope, N fourth laser signals can be transmitted, and N fifth laser signals can be reflected. The third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes a fourth laser signal and a fifth laser signal. N sixth laser signals can also be received by a detector, and the N sixth laser signals can be converted into electrical signals to obtain N fourth electrical signals. The sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector. The filter coefficient of the filter can also be adjusted according to the N fourth electrical signals by the control module, and the second superposition signal can also be filtered according to the N first sequences by the control module filter to obtain N filtered signals.

[0170] In one embodiment, a control module can be used to determine whether a correlation peak exists between the first superimposed signal and the first sequence. When a correlation peak exists and the value of the main-to-sidelobe ratio of the correlation peak is greater than a first threshold, the control module can be used to determine N first sequences as N second sequences and determine N groups of first time intervals as N groups of second time intervals.

[0171] In one embodiment, a control module can be used to determine whether a correlation peak exists between the first superimposed signal and the first sequence. When a correlation peak exists and the value of the main-to-sidelobe ratio is less than or equal to a first threshold, the control module can be used to increase the interval length and / or the number of intervals included in each group of N groups of first time intervals to obtain N groups of first time intervals.

[0172] In one embodiment, when there is a correlation peak between the first superimposed signal and the first sequence, and the value of the main-to-sidelobe ratio is greater than the second threshold, the control module can reduce the interval length and / or the number of intervals of each group of first time intervals in N groups of first time intervals to obtain N groups of first time intervals, and the second threshold is greater than the first threshold.

[0173] In one embodiment, the control module may determine whether there is a correlation peak between the first superimposed signal and the first sequence. When there is no correlation peak, the N first sequences are adjusted to obtain N first sequences.

[0174] In one embodiment, a control module can be used to determine whether there is a correlation peak between the first superimposed signal and the first sequence. When there is no correlation peak and the signal-to-noise ratio of the first superimposed signal is greater than a third threshold, the control module can be used to adjust the N first sequences to obtain N first sequences.

[0175] In one embodiment, the interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

[0176] In one embodiment, after the control module obtains the first superimposed signal and before determining whether there is a correlation peak between the first superimposed signal and the first sequence, the control module can perform dynamic threshold detection on the first superimposed signal. That is, the control module can determine whether the amplitude of the first superimposed signal is greater than the dynamic threshold. When it is greater than the dynamic threshold value, it can be further determined whether there is a correlation peak between the first superimposed signal and the first sequence. When it is less than or equal to the dynamic threshold value, the first superimposed signal can be discarded.

[0177] It should be noted that the relevant functions of the specific process in the laser radar anti-interference method described in the embodiment of the present application can be found in the above Figure 3 , Figure 5 and Figure 8 The relevant description in the laser radar anti-interference device embodiment will not be repeated here.

[0178] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation methods of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the present application should be included in the scope of protection of the present application.

Claims

1. A laser radar anti-interference device, characterized in that: The device comprises a control module, a laser, a detector and a signal generator for generating an electrical signal, wherein: The control module is used to determine N first sequences and N groups of first time intervals, where N is an integer greater than or equal to 1; The laser is used to emit N first laser signals according to the N first sequences and the N groups of first time intervals; The detector is used to receive N second laser signals and convert the N second laser signals into electrical signals to obtain N first electrical signals; The control module is further configured to superimpose the N first electrical signals to obtain a first superimposed signal, and determine N second sequences and N groups of second time intervals according to the first superimposed signal.

2. The device according to claim 1, characterized in that When the N first sequences are the same sequence, the control module superimposing the N first electrical signals to obtain a first superimposed signal includes: Superimposing the N first electrical signals according to the N groups of first time intervals to obtain a second superimposed signal; The second superimposed signal is filtered according to the N first sequences to obtain a first superimposed signal.

3. The device according to claim 1, characterized in that When the N first sequences are different sequences, the control module superimposing the N first electrical signals to obtain a first superimposed signal includes: Filtering the N first electrical signals according to the N first sequences to obtain N filtered signals; The N filtered signals are superimposed according to the N groups of first time intervals to obtain a first superimposed signal.

4. The device according to claim 2, characterized in that The device further comprises a spectroscope, and the control module comprises a filter, wherein: The spectroscope is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes the fourth laser signal and the fifth laser signal; The detector is further used to receive the N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N third electrical signals, wherein the sixth optical signal is a laser signal transmitted from the fifth laser signal to the detector; The control module filters the second superimposed signal according to the N first sequences to obtain the first superimposed signal, comprising: The control module adjusts the filter coefficient of the filter according to the N third electrical signals; The filter filters the second superimposed signal according to the N first sequences to obtain a first superimposed signal.

5. The device according to claim 3, characterized in that The device further comprises a spectroscope, and the control module comprises a filter, wherein: The spectroscope is used to receive N third laser signals, transmit N fourth laser signals, and reflect N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the spectroscope, and the third laser signal includes the fourth laser signal and the fifth laser signal; The detector is further used to receive N sixth laser signals, convert the N sixth laser signals into electrical signals, and obtain N fourth electrical signals, wherein the sixth laser signal is a laser signal transmitted to the detector by the fifth laser signal; The control module filters the N first electrical signals according to the N first sequences to obtain N filtered signals, including: The control module adjusts the filter coefficient of the filter according to the N fourth electrical signals; The filter filters the second superimposed signal according to the N first sequences to obtain N filtered signals.

6. The device according to any one of claims 1 to 5, characterized in that: The control module determines N second sequences and N groups of second time intervals according to the first superposition signal, including: When there is a correlation peak between the N first sequences and the first superimposed signal, and the value of the main-to-sidelobe ratio of the correlation peak is greater than a first threshold, the N first sequences are determined as the N second sequences, and the N groups of first time intervals are determined as the N groups of second time intervals.

7. The device according to claim 6, characterized in that The control module determining N second sequences and N groups of second time intervals according to the first superposition signal further includes: When the correlation peak exists and the value of the main-to-sidelobe ratio is less than or equal to the first threshold, the interval length and / or the number of intervals included in each group of the N groups of first time intervals is increased to obtain N groups of first time intervals.

8. The device according to claim 6 or 7, characterized in that The control module determining N second sequences and N groups of second time intervals according to the first superposition signal further includes: When the correlation peak does not exist, the N first sequences are adjusted to obtain N first sequences.

9. The device according to claim 8, characterized in that The control module determining N second sequences and N groups of second time intervals according to the first superposition signal further includes: When the value of the main-to-sidelobe ratio is greater than the second threshold, the interval length and / or number of each group of first time intervals in the N groups of first time intervals is reduced to obtain N groups of first time intervals, and the second threshold is greater than the first threshold.

10. The device according to claim 8, characterized in that The control module determining N second sequences and N groups of second time intervals according to the first superposition signal further includes: When the signal-to-noise ratio of the first superimposed signal is greater than the third threshold, the N first sequences are adjusted to obtain N first sequences.

11. The device according to any one of claims 1 to 10, characterized in that: The interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

12. A laser radar anti-interference method, characterized in that: The method is applied to a laser radar anti-interference device, and the method comprises: Determine N first sequences and N groups of first time intervals, where N is an integer greater than or equal to 1; Transmitting N first laser signals according to the N first sequences and the N groups of first time intervals; Receiving N second laser signals, converting the N second laser signals into electrical signals to obtain N first electrical signals; Superimposing the N first electrical signals to obtain a first superimposed signal; N second sequences and N groups of second time intervals are determined according to the first superimposed signal.

13. The method according to claim 12, characterized in that The method further comprises: Generate N second electrical signals according to the N first sequences and the N groups of first time intervals; The transmitting N first laser signals according to the N first sequences and the N groups of first time intervals comprises: N first laser signals are emitted according to the N second electrical signals.

14. The method according to claim 12 or 13, characterized in that When the N first sequences are the same sequence, superimposing the N first electrical signals to obtain a first superimposed signal includes: Superimposing the N first electrical signals according to the N groups of first time intervals to obtain a second superimposed signal; The second superimposed signal is filtered according to the N first sequences to obtain a first superimposed signal.

15. The method according to claim 12 or 13, characterized in that When the N first sequences are different sequences, superimposing the N first electrical signals to obtain a first superimposed signal includes: Filtering the N first electrical signals according to the N first sequences to obtain N filtered signals; The N filtered signals are superimposed according to the N groups of first time intervals to obtain a first superimposed signal.

16. The method according to claim 14, characterized in that The method further comprises: receiving N third laser signals, transmitting N fourth laser signals, and reflecting N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the beam splitter, and the third laser signal includes the fourth laser signal and the fifth laser signal; receiving N sixth laser signals, converting the N sixth laser signals into electrical signals to obtain N third electrical signals, wherein the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; The filtering the second superimposed signal according to the N first sequences to obtain the first superimposed signal comprises: adjusting a filter coefficient of the filter according to the N third electrical signals; The second superimposed signal is filtered according to the N first sequences to obtain a first superimposed signal.

17. The method according to claim 15, characterized in that The method further comprises: receiving N third laser signals, transmitting N fourth laser signals, and reflecting N fifth laser signals, wherein the third laser signal is a laser signal transmitted from the first laser signal to the beam splitter, and the third laser signal includes the fourth laser signal and the fifth laser signal; receiving N sixth laser signals, converting the N sixth laser signals into electrical signals to obtain N fourth electrical signals, wherein the sixth laser signal is a laser signal transmitted from the fifth laser signal to the detector; The filtering the N first electrical signals according to the N first sequences to obtain N filtered signals comprises: adjusting a filter coefficient of the filter according to the N fourth electrical signals; The second superimposed signal is filtered according to the N first sequences to obtain N filtered signals.

18. The method according to any one of claims 12 to 17, characterized in that: The determining, according to the first superposition signal, N second sequences and N groups of second time intervals comprises: When there is a correlation peak between the N first sequences and the first superimposed signal, and the value of the main-to-sidelobe ratio of the correlation peak is greater than a first threshold, the N first sequences are determined as the N second sequences, and the N groups of first time intervals are determined as the N groups of second time intervals.

19. The method according to claim 18, characterized in that The determining of N second sequences and N groups of second time intervals according to the first superposition signal further comprises: When the correlation peak exists and the value of the main-to-sidelobe ratio is less than or equal to the first threshold, the interval length and / or the number of intervals included in each group of the N groups of first time intervals is increased to obtain N groups of first time intervals.

20. The method according to claim 18 or 19, characterized in that The determining of N second sequences and N groups of second time intervals according to the first superposition signal further comprises: When the correlation peak does not exist, the N first sequences are adjusted to obtain N first sequences.

21. The method according to claim 18, characterized in that The determining of N second sequences and N groups of second time intervals according to the first superposition signal further comprises: When the value of the main-to-sidelobe ratio is greater than the second threshold, the interval length and / or number of each group of first time intervals in the N groups of first time intervals is reduced to obtain N groups of first time intervals, and the second threshold is greater than the first threshold.

22. The method according to claim 20, characterized in that The determining of N second sequences and N groups of second time intervals according to the first superposition signal further comprises: When the signal-to-noise ratio of the first superimposed signal is greater than the third threshold, the N first sequences are adjusted to obtain N first sequences.

23. The method according to any one of claims 12 to 22, characterized in that: The interval lengths included in the N groups of second time intervals are less than or equal to a fourth threshold, and the number of intervals in the N groups of second time intervals is less than or equal to a fifth threshold.

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