Dual-pulse blind area signal processing method, device, radar and storage medium

Abstract

This application is applicable to the field of computer technology and provides a method for processing dual-pulse blind zone signals applied to lidar, including: capturing echo signals corresponding to two detection pulses; delaying the echo signals forward by a duration corresponding to the transmission time interval to obtain first echo signals; adding N zeros to the tail of the echo signals to obtain second echo signals; obtaining first mixed echo signals based on the first echo signals and the second echo signals; deleting the first N signals of the first mixed echo signals to obtain second mixed echo signals; splicing the first N points of the second echo signals with the second mixed echo signals to obtain target echo signals; where N is the number of sampling points corresponding to the transmission time interval. It can effectively remove the problem of short-range blind zones caused by the delay between two detection pulses and improve the short-range detection performance and ranging accuracy of the radar in dual-pulse mode.

Description

Technical Field

[0001] This application belongs to the field of computer technology, and particularly relates to a dual-pulse blind area signal processing method, device, radar and storage medium for lidar. Background Art

[0002] Lidar is commonly used in the field of autonomous driving because it has less restrictions on the usage environment and lower cost compared to millimeter-wave radar. Since dual-pulse mode lidar has the advantage of a longer detection range compared to single-pulse lidar, it is often used in the field of autonomous driving. However, dual-pulse mode lidar has a problem of a close-range blind area, which greatly reduces the near-field detection ability of lidar, making it impossible for vehicles to accurately identify close-range targets and posing a great safety hazard. Summary of the Invention

[0003] In view of this, embodiments of this application provide a dual-pulse blind area signal processing method, device, radar and storage medium to solve the problem of the close-range blind area of dual-pulse mode lidar in the prior art and improve the close-range detection performance of dual-pulse mode lidar.

[0004] The first aspect of the embodiments of this application provides a dual-pulse blind area signal processing method for lidar, including the following steps:

[0005] Capture the echo signals generated by the reflection of two detection pulses by the target detection object, where the two detection pulses are detection pulses sent according to a preset emission time interval within one detection period;

[0006] Delay the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal;

[0007] Add N zeros to the tail of the echo signal to obtain a second echo signal;

[0008] Delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal;

[0009] Perform signal splicing on the first N signals of the second echo signal and the second mixed echo signal to obtain a target echo signal;

[0010] Wherein, N is the number of sampling points corresponding to the emission time interval.

[0011] Optionally, after obtaining the target echo signal based on the two delayed echo signals, it includes:

[0012] Determine the distance to the target detection object according to the target echo signal and the emission time interval.

[0013] Optionally, capturing the echo signals generated by the target detector emitting in response to two detection pulses includes:

[0014] Obtaining the reflection signals generated by the reflection of the two detection pulses at the detection target;

[0015] Performing high-pass filtering on the reflection signals to obtain the echo signals.

[0016] Optionally, before delaying the echo signals forward by a duration corresponding to the emission time interval to obtain the first echo signals, it includes:

[0017] Multiplying the echo signals by a preset compensation time signal to obtain compensated echo signals.

[0018] Optionally, delaying the echo signals forward by a duration corresponding to the emission time interval to obtain the first echo signals includes:

[0019] Delaying the compensated echo signals forward by a duration corresponding to the emission time interval to obtain the first echo signals.

[0020] Optionally, delaying the echo signals backward by a duration corresponding to the emission time interval to obtain the second echo signals includes:

[0021] Adding N zeros to the tail of the compensated echo signals to obtain the second echo signals.

[0022] Optionally, the compensation time signal is calculated based on the pulse width of the detection pulse, the duration corresponding to the emission time interval, and the time interval between the trailing edge of the first detection pulse and the leading edge of the second detection pulse. The first detection pulse and the second detection pulse are two detection pulses transmitted according to a preset emission time interval within one detection cycle.

[0023] Optionally, obtaining the mixed echo signals based on the first echo signals and the second echo signals includes:

[0024] Adding the first echo signals and the second echo signals to generate a sum signal;

[0025] Subtracting the first echo signals from the second echo signals and taking the absolute value to generate a difference signal;

[0026] Taking the difference between the sum signal and the difference signal as the mixed echo signals.

[0027] A second aspect of the embodiments of the present application provides a lidar, including a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes the steps of the dual-pulse blind area signal processing method for lidar provided in the first aspect above.

[0028] A fourth aspect of the embodiments of the present application provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the dual-pulse blind area signal processing method for lidar provided in the first aspect above are implemented.

[0029] Compared with the prior art, the dual-pulse blind area signal processing method for lidar provided in the first aspect of the present application captures the echo signals corresponding to two detection pulses, where the two detection pulses are detection pulses sent according to a preset transmission time interval within one detection period; delays the echo signal forward by a duration corresponding to the transmission time interval to obtain a first echo signal; adds N zeros to the tail of the echo signal to obtain a second echo signal; obtains a first mixed echo signal based on the first echo signal and the second echo signal; deletes the first N points of the first mixed echo signal to obtain a second mixed echo signal; splices the first N points of the second echo signal with the second mixed echo signal to obtain a target echo signal; where N is the number of sampling points corresponding to the transmission time interval. Since the echo signal is delayed forward by a duration corresponding to the transmission time interval to obtain the first echo signal and backward supplemented with the number of sampling points corresponding to the transmission time interval to obtain the second echo signal, and then corresponding signal splicing operations are performed based on the first echo signal and the second echo signal to obtain the target echo signal, it can effectively remove the problem of the near-distance blind area caused by the delay between the two detection pulses, and improve the near-distance detection performance and ranging accuracy of the radar in the dual-pulse mode.

[0030] The lidar provided in the second aspect of the present application and the computer-readable storage medium provided in the third aspect have the same corresponding beneficial effects as those of the dual-pulse blind area signal processing method for lidar provided in the first aspect of the present application, and will not be elaborated here. Description of the Drawings

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] Figure 1It is the implementation flowchart of the dual-pulse blind area signal processing method applied to lidar provided by the first embodiment of the present application;

[0033] Figure 2 It is Figure 1 the specific implementation flowchart of S101 in

[0034] Figure 3 It is Figure 1 the specific implementation flowchart of S104 in

[0035] Figure 4 It is the implementation flowchart of the dual-pulse blind area signal processing method applied to lidar provided by the second embodiment of the present application;

[0036] Figure 5 It is the waveform diagram of the compensation time signal provided by the present application;

[0037] Figure 6 It is the waveform diagram of two echo signals with delay provided by the present application;

[0038] Figure 7 It is Figure 5 in the compensation time signal and Figure 6 the waveform diagram of the compensated echo signal after multiplying the echo signal in

[0039] Figure 8 It is the implementation flowchart of the dual-pulse blind area signal processing method applied to lidar provided by the third embodiment of the present application;

[0040] Figure 9 It is the schematic diagram of the functional modules of the dual-pulse blind area signal processing device applied to lidar provided by the embodiment of the present application;

[0041] Figure 10 It is the schematic diagram of the lidar provided by the embodiment of the present application. Specific Embodiments

[0042] In the following description, specific details such as specific system architectures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application. It should be noted that currently, in a common dual-pulse mode lidar, the transmitter emits two detection pulses within a detection period according to a preset time interval. After the two detection pulses propagate through space, the echo signals received by the lidar usually include interference signals, such as signals generated by real targets reflecting detection pulses emitted by other radars, false echo signals generated by silicon photomultipliers (SiPMs) inside the lidar, and Gaussian noise signals, etc. These interference signals make it necessary for the receiver of the lidar to filter and anti-interference process the received echo signals to obtain real echo signals. During the process of filtering and anti-interference processing of the received echo signals by a common dual-pulse mode lidar, the problem of the near-blind zone of the dual-pulse mode lidar is usually not considered, resulting in relatively low near-distance detection performance of the dual-pulse mode lidar. The present application proposes a new solution to the problem of the near-blind zone of the dual-pulse mode lidar.

[0043] To illustrate the technical solutions described in the present application, the following will be described through specific embodiments. As Figure 1 shown, Figure 1 is a flowchart of the implementation of a dual-pulse blind zone signal processing method applied to a lidar provided in the first embodiment of the present application. The dual-pulse blind zone signal processing method applied to a lidar proposed by the present application is applicable to a lidar. For the sake of convenience of description, only the parts related to this embodiment are shown and are described in detail as follows:

[0044] S101, capture the echo signals generated by two detection pulses being reflected by a target detection object, where the two detection pulses are detection pulses sent within a detection period according to a preset transmission time interval.

[0045] In a possible implementation manner, the lidar transmitter sends two detection pulses within a detection period according to a preset transmission time interval, where the transmission time interval can be set in advance according to actual detection needs, and the transmission time interval is less than the detection period. For example, if the detection period is t and the transmission time interval is Nt, then Nt < t.

[0046] Specifically, when the detection pulse detects an object, reflection occurs and a corresponding reflection signal is generated. In this embodiment, since the lidar transmitter sends two detection pulses according to a preset transmission time interval within one detection cycle, the time interval between the two detection pulses detecting the same object is the same as the transmission time interval, resulting in a certain time delay between the captured echo signals.

[0047] Optionally, as Figure 2 shown, is Figure 1 the specific implementation flowchart of S101 in Figure 2 It can be seen that S101 includes:

[0048] S1011, obtain the reflection signals generated by the reflection of the two detection pulses when encountering the target detection object.

[0049] Specifically, when the distance between the target detection object and the lidar is relatively close, for example, the time delay between the reflection signals generated by the two detection pulses reaching the target detection object and reflecting is less than the transmission time interval. For example, if the transmission time interval is Nt, then when the time delay between the reflection signals generated by the two detection pulses reaching the target detection object and reflecting is between 0 and Nt, the lidar obtains one reflection signal. This is because the lidar has received the reflection signal generated by the first detection pulse encountering the target detection object before it has sent the second detection pulse. When the target detection object is far from the lidar, for example, the time delay between the reflection signals generated by the two detection pulses reaching the target detection object and reflecting is greater than or equal to the transmission time interval, the lidar obtains two delayed reflection signals.

[0050] Furthermore, the reflection signal is a complex signal. In the specific implementation process, for the convenience of the signal processing process, it is necessary to perform DC component removal processing on the reflection signal.

[0051] S1012, perform DC removal processing on the reflection signal to obtain the echo signal.

[0052] For example, the DC component in the reflection signal can be removed by means of high-pass filtering to obtain the echo signal. It should be noted that in the signal processing process, the DC is constant and basically cannot be used to express the information of the detected object. Therefore, DC removal processing can be performed first to facilitate subsequent operations. It can be understood that the above method of removing the DC component is only an example and not a limitation.

[0053] S102, delay the echo signal forward by the duration corresponding to the transmission time interval to obtain the first echo signal.

[0054] Specifically, in this embodiment, the echo signal is delayed forward by a duration corresponding to the transmission time interval to obtain a first echo signal. Specifically, it includes adding Nt zeros at the starting position of the echo signal, where Nt is the duration corresponding to the transmission time interval, to obtain the first echo signal.

[0055] S103. Add N zeros at the tail of the echo signal to obtain a second echo signal.

[0056] Specifically, N is the number of sampling points corresponding to the transmission time interval. In this example, by adding N zeros at the tail of the echo signal, the second echo signal is made to match the first echo signal in length.

[0057] S104. Obtain a mixed echo signal based on the first echo signal and the second echo signal.

[0058] Specifically, as Figure 3 shown, it is Figure 1 the specific implementation flowchart of S104. As can be seen from Figure 3 , S104 includes:

[0059] S1041. Add the first echo signal and the second echo signal to generate a sum signal.

[0060] Specifically, within one detection period, add the signal of each sampling point corresponding to the first echo signal to the signal of each sampling point corresponding to the second echo signal to generate a sum signal for one detection period.

[0061] S1042. Subtract the first echo signal from the second echo signal and take the absolute value to generate a difference signal.

[0062] Specifically, within one detection period, subtract the signal of each sampling point corresponding to the first echo signal from the signal of each sampling point corresponding to the second echo signal, and take the absolute value of the subtracted signal to generate a difference signal.

[0063] S1043. Use the difference between the sum signal and the difference signal as the mixed signal.

[0064] Specifically, within one detection period, subtract the difference signal corresponding to each sampling point from the sum signal corresponding to each sampling point to obtain the mixed signal.

[0065] S105. Delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal. Concatenate the first N signals of the second echo signal with the second mixed echo signal to obtain the target echo signal.

[0066] Where N is the number of sampling points corresponding to the transmission time interval.

[0067] It should be noted that within a detection period, the range of the near-field blind zone depends on the time interval T between the trailing edge of the first detection pulse and the leading edge of the second detection pulse among the two detection pulses. Specifically, the length of the near-field blind zone is: where c is the speed of light.

[0068] During the time interval between the trailing edge of the first detection pulse and the leading edge of the second detection pulse among the two detection pulses, the obtained echo signal corresponds to the number of sampling points within the emission time interval. Therefore, in this embodiment, after obtaining the mixed echo signal, the first N signals corresponding to the mixed echo signal are deleted to obtain the second mixed echo signal, and the first N signals of the second echo signal are spliced with the second mixed echo signal to obtain the target echo signal. It should be noted that in practical applications, the first N signals corresponding to the mixed echo signal are the signal range of the near-field blind zone. In this embodiment, deleting the first N signals corresponding to the mixed echo signal to obtain the second mixed echo signal, and splicing the first N signals of the second echo signal with the second mixed echo signal to obtain the target echo signal can solve the problem of the near-field blind zone of the dual-pulse mode lidar and realize the normal detection of near-field targets by the dual-pulse mode lidar.

[0069] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not imply the order of execution. The order of execution of each process should be determined by its function and internal logic and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0070] As can be seen from the above analysis, the dual-pulse blind zone signal processing method for lidar proposed in this embodiment captures the echo signals generated by the target object when two detection pulses are emitted. The two detection pulses are detection pulses sent according to a preset emission time interval within one detection period. The echo signal is delayed forward by a duration corresponding to the emission time interval to obtain a first echo signal. N zeros are added to the tail of the echo signal to obtain a second echo signal. A mixed echo signal is obtained based on the first echo signal and the second echo signal. The first N signals of the first mixed echo signal are deleted to obtain a second mixed echo signal. The first N signals of the second echo signal are spliced with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval. Since the first echo signal and the second echo signal are respectively obtained based on the captured echo signal and the duration corresponding to the emission time interval, and after obtaining the mixed echo signal based on the first echo signal and the second echo signal, the first N signals of the first mixed echo signal are deleted to obtain a second mixed echo signal, and the first N signals of the second echo signal are spliced with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval, the problem of the short-distance blind zone of the dual-pulse lidar can be solved, and the normal detection of the short-distance target by the dual-pulse lidar can be realized.

[0071] It should be noted that although the problem of the short-distance blind zone can be solved through the above embodiment, there may be a problem of distortion of the target echo signal. Specifically, when the delay between the reflection signals generated by the target object for the two detection pulses is exactly equal to the emission time interval, the target echo signal obtained through the above embodiment will have a problem of distortion of the target echo signal at the Nth sampling point (the transition point from the short-distance blind zone to the dual-pulse enhancement). Therefore, it is necessary to further prevent the problem of signal distortion.

[0072] Specifically, as Figure 4 shown, it is a flowchart of the implementation of a dual-pulse blind zone signal processing method for lidar provided by the second embodiment of the present application. As can be seen from Figure 2 this, compared with the embodiment shown in Figure 1 , the specific implementation processes of S401 and S101 are the same, and the specific implementation processes of S405 - S406 are the same as those of S104 - S105. The difference is that S402 is included before S403, and the specific implementation processes of S403 - S404 are the same as those of S102 - S103. It should be noted that S402 is executed after S401. Specifically, the specific implementation processes of S402 - S404 are described in detail as follows:

[0073] S402, multiply the echo signal with a preset compensation time signal to obtain a compensated echo signal.

[0074] Specifically, the preset compensation time signal within the detection period is a compensation time signal determined according to the emission time interval between two detection pulses, the emission times of the two detection pulses, and the time delay between the two detection pulses.

[0075] In a possible implementation, the compensation time signal is:

[0076]

[0077] where pulse_T is the pulse width of the detection pulse, Nt is the duration corresponding to the emission time interval, and T is the time interval between the trailing edge of the first detection pulse and the leading edge of the second detection pulse among the two detection pulses.

[0078] Optionally, as Figures 5 to 7 shown, Figure 5 is the waveform diagram of the compensation time signal provided by this application. Figure 6 is the waveform diagram of two echo signals with delay provided by this application. Figure 7 is Figure 5 the compensated echo signal waveform diagram after multiplying the compensation time signal in Figure 6 with the echo signal in

[0079] Specifically, as Figure 5 shown, the compensation time signal takes a value of 1 within the range of 0 to the pulse width pulse_T of the detection pulse, is in an upward trend during the time period t between the trailing edge of the first detection pulse and the leading edge of the second detection pulse, that is, rises from 1 to 2, and remains at 2 starting from the leading edge of the second detection pulse.

[0080] Specifically, as Figure 6 shown, after the two detection pulses propagate a certain distance, the radar receiver captures two echo signals generated by the reflection of the two detection pulses at the target detection object. As can be seen from Figure 6 , in this embodiment, there is a delay of 50 sampling points between the two echo signals.

[0081] Specifically, as Figure 7 shown, after multiplying the compensated echo signal obtained by multiplying the compensation time signal in Figure 5 with the echo signal in Figure 6 , the compensated echo signal is obtained. It should be noted that based on the compensated echo signal, the signal distortion problem of the target echo signal obtained after filtering and anti-interference processing of the echo signal due to the delay between the two reflected echo signals can be compensated.

[0082] S403. Delay the compensated echo signal forward by a duration corresponding to the transmit time interval to obtain the first echo signal.

[0083] S404. Add N zeros at the tail of the compensated echo signal to obtain the second echo signal.

[0084] It should be noted that when the delay between the reflection signals generated by the target detector for two detection pulses is exactly equal to the transmit time interval, there will be a problem of distortion of the target echo signal at the Nth sampling point (the transition point from the near - range blind zone to double - pulse enhancement). That is, when the target appears at the Nth sampling point, through Figure 1 the signal processing method in the embodiment, it is easy to have a problem of signal distortion. Therefore, in this embodiment, by delaying the compensated echo signal forward by a duration corresponding to the transmit time interval to obtain the first echo signal and delaying the compensated echo signal backward by a duration corresponding to the transmit time interval to compensate for the distortion problem that occurs at the Nth sampling point.

[0085] Specifically, the step of delaying the compensated echo signal forward by a duration corresponding to the transmit time interval to obtain the first echo signal includes: adding Nt zeros at the starting position of the compensated echo signal to obtain the first echo signal, where Nt is the duration corresponding to the transmit time interval.

[0086] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0087] As can be seen from the above analysis, the dual-pulse blind zone signal processing method for lidar proposed in this embodiment captures the echo signals generated by the two detection pulses encountering the target object. The two detection pulses are the detection pulses sent according to the preset emission time interval within one detection period. Multiply the echo signal by the preset compensation time signal to obtain a compensated echo signal. Delay the compensated echo signal forward by the duration corresponding to the emission time interval to obtain a first echo signal. Add N zeros to the tail of the compensated echo signal to obtain a second echo signal. Obtain a mixed echo signal based on the first echo signal and the second echo signal. Delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal. Splices the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval. Since a preset compensation time signal is added, and the first echo signal and the second echo signal are respectively obtained based on the echo signal, the preset compensation time signal, and the duration corresponding to the emission time interval, and after obtaining the mixed echo signal based on the first echo signal and the second echo signal, delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal, and splice the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval, it can solve the problem of the near-distance blind zone of the dual-pulse mode lidar while solving the problem of signal distortion of the target echo signal, and realize the normal detection of near-distance targets by the dual-pulse mode lidar.

[0088] As Figure 8 shown, it is a flowchart of the implementation of a dual-pulse blind zone signal processing method for lidar provided in the third embodiment of the present application. As Figure 8 can be seen, compared with the embodiment shown in Figure 4 , the specific implementation processes of S801 to S806 are the same as those of S401 to S406. The difference is that after S806, S807 is further included. Specifically, S807 is described in detail as follows:

[0089] S807, determine the distance to the target object according to the target echo signal and the emission time interval.

[0090] Generally, the peak position in the target echo signal corresponds to the position of the target detector. When the echo signals are generated by the reflection of two detection pulses encountering the target detector, through experiments, it can be known that when the target detector is in the near-distance blind area, after being processed by the above method, there is only one peak position in the target echo signal, and this peak position corresponds to the position of the target detector. When the target detector is not in the near-distance blind area, after being processed by the above method, two peaks will appear in the target echo signal. At this time, taking the emission time interval as the time delay of the target detector, the position corresponding to the peak with the emission time interval time delay in the target echo signal is determined as the position of the target detector. It should be noted that the position of the target detector is at the position with the largest peak in the target echo signal.

[0091] From the above analysis, it can be seen that the dual-pulse blind area signal processing method applied to lidar proposed in this embodiment captures the echo signals generated by the emission of two detection pulses encountering the target detector. The two detection pulses are detection pulses sent according to a preset emission time interval within one detection period; multiplying the echo signal by a preset compensation time signal to obtain a compensated echo signal; delaying the compensated echo signal forward by the duration corresponding to the emission time interval to obtain a first echo signal; adding N zeros at the tail of the compensated echo signal to obtain a second echo signal; obtaining a mixed echo signal based on the first echo signal and the second echo signal; deleting the first N signals of the first mixed echo signal to obtain a second mixed echo signal, splicing the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval. Since a preset compensation time signal is added, and the first echo signal and the second echo signal are respectively obtained based on the echo signal, the preset compensation time signal, and the duration corresponding to the emission time interval, and after obtaining the mixed echo signal based on the first echo signal and the second echo signal, deleting the first N signals of the first mixed echo signal to obtain a second mixed echo signal, splicing the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal, where N is the number of sampling points corresponding to the emission time interval, it can solve the near-distance blind area problem of the dual-pulse mode lidar and at the same time solve the signal distortion problem of the target echo signal, realizing the normal detection of near-distance targets by the dual-pulse mode lidar.

[0092] Figure 9 It is a schematic diagram of the functional modules of the dual-pulse blind area signal processing device applied to lidar provided by this application. As Figure 9As shown in the figure, the dual-pulse blind area signal processing device 9 applied to lidar includes: an echo signal capture module 910, a first echo signal acquisition module 920, a second echo signal acquisition module 930, a mixed echo signal acquisition module 940, and a target echo signal acquisition module 950. Among them,

[0093] The echo signal capture module 910 is used to capture the echo signals generated by the two detection pulses encountering the target object for emission. The two detection pulses are detection pulses sent according to a preset emission time interval within one detection period;

[0094] The first echo signal acquisition module 920 is used to delay the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal;

[0095] The second echo signal acquisition module 930 is used to add N zeros to the tail of the echo signal to obtain a second echo signal;

[0096] The mixed echo signal acquisition module 940 is used to obtain a mixed echo signal based on the first echo signal and the second echo signal;

[0097] The target echo signal acquisition module 950 is used to delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal, and splice the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal;

[0098] Among them, N is the number of sampling points corresponding to the emission time interval.

[0099] Preferably, it further includes:

[0100] The target object distance determination module is used to determine the distance to the target object according to the target echo signal and the emission time interval.

[0101] Preferably, the echo signal capture module 910 includes:

[0102] An acquisition unit is used to acquire the reflection signals generated by the two detection pulses reflecting at the detection target;

[0103] A obtaining unit is used to perform high-pass filtering on the reflection signal to obtain the echo signal.

[0104] Preferably, it further includes:

[0105] The compensated echo signal acquisition module is used to multiply the echo signal by a preset compensated time signal to obtain a compensated echo signal.

[0106] Preferably, the first echo signal acquisition module 920 is further configured to:

[0107] Delay the compensated echo signal forward by a duration corresponding to the transmission time interval to obtain the first echo signal.

[0108] Preferably, the second echo signal acquisition module 930 is further configured to:

[0109] Add N zeros to the tail of the compensated echo signal to obtain the second echo signal.

[0110] Preferably, the compensation time signal is calculated according to the pulse width of the detection pulse, the duration corresponding to the transmission time interval, and the time interval between the trailing edge of the first detection pulse and the leading edge of the second detection pulse. The first detection pulse and the second detection pulse are two detection pulses transmitted according to a preset transmission time interval within one detection period.

[0111] Preferably, the mixed echo signal acquisition module 940 includes:

[0112] A first generation unit, configured to add the first echo signal and the second echo signal to generate a sum signal;

[0113] A second generation unit, configured to subtract the first echo signal from the second echo signal and take the absolute value to generate a difference signal;

[0114] A subtraction unit, configured to use the difference between the sum signal and the difference signal as the mixed echo signal.

[0115] Figure 10 is a schematic diagram of a lidar provided by an embodiment of the present application. As Figure 10 shown, the lidar 10 of this embodiment includes: a processor 100, a memory 110, and a computer program 120 stored in the memory 110 and executable on the processor 100, such as a dual-pulse blind area signal processing program applied to a lidar. When the processor 100 executes the computer program 120, the steps in the above-mentioned embodiments of the dual-pulse blind area signal processing method applied to a lidar are implemented, such as Figure 1 the steps 101 to 105 shown. Alternatively, when the processor 100 executes the computer program 120, the functions of the modules / units in the above-mentioned embodiments of the dual-pulse blind area signal processing device applied to a lidar are implemented, such as Figure 9 the functions of the modules 910 to 950 shown.

[0116] Exemplarily, the computer program 120 may be divided into one or more modules / units, which are stored in the memory 110 and executed by the processor 100 to complete this application. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and these instruction segments are used to describe the execution process of the computer program 120 in the lidar 10. For example, the computer program 120 may be divided into an echo signal capture module, a first echo signal acquisition module, a second echo signal acquisition module, a mixed echo signal acquisition module, and a target echo signal acquisition module (modules in the virtual device), and the specific functions of each module are as follows:

[0117] The echo signal capture module is configured to capture echo signals generated by two detection pulses encountering a target object for emission. The two detection pulses are detection pulses sent according to a preset emission time interval within one detection period;

[0118] The first echo signal acquisition module is configured to delay the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal;

[0119] The second echo signal acquisition module is configured to add N zeros to the tail of the echo signal to obtain a second echo signal;

[0120] The mixed echo signal acquisition module is configured to obtain a mixed echo signal based on the first echo signal and the second echo signal;

[0121] The target echo signal acquisition module is configured to delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal, and splice the first N signals of the second echo signal with the second mixed echo signal to obtain a target echo signal;

[0122] Wherein, N is the number of sampling points corresponding to the emission time interval.

[0123] Those skilled in the art can understand that Figure 10 This is only a possible implementation manner of the lidar, and does not constitute a limitation on the lidar. It may further include more or fewer components than shown in the figure, or combine some components. For example, it may further include input / output devices, communication access devices, buses, etc.

[0124] The processor 100 can be a Central Processing Unit (CPU), or it can also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0125] The memory 110 can be an internal storage unit of the lidar, such as the hard disk or memory of the lidar. The memory 110 can also be an external storage device of the lidar 10, such as a plug-in hard disk equipped on the lidar 10, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. Further, the memory 110 can also include both the internal storage unit of the lidar 10 and the external storage device. The memory 110 is used to store the computer program 120 and other programs and data required by the lidar 10. The memory 110 can also be used to temporarily store the data that has been output or will be output.

[0126] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is used as an example. In practical applications, the above functions can be allocated to different functional units and modules according to needs, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction and do not limit the protection scope of this application. The specific working process of the units and modules in the above system can refer to the corresponding process in the foregoing method embodiment and will not be elaborated here.

[0127] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0128] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0129] In the embodiments provided in this application, it should be understood that the disclosed devices / radars and methods can be implemented in other ways. For example, the device / radar embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of the devices or units can be in electrical, mechanical or other forms.

[0130] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple communication units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0131] In addition, the functional units in each embodiment of this application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0132] When the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, to implement all or part of the processes in the above-described embodiment methods of the present application, it can also be completed by a computer program instructing relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-described various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0133] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for processing double - pulse blind - area signals applied to lidar, characterized in that, it includes the following steps: Capture the echo signals generated by the reflection of two detection pulses encountering a target object, where the two detection pulses are detection pulses sent according to a preset emission time interval within one detection period; Delay the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal; Add N zeros to the tail of the echo signal to obtain a second echo signal; Obtain a first mixed echo signal based on the first echo signal and the second echo signal, including: adding the first echo signal and the second echo signal to generate a sum signal; subtracting the first echo signal from the second echo signal and taking the absolute value to generate a difference signal; using the difference between the sum signal and the difference signal as the first mixed echo signal; Delete the first N signals of the first mixed echo signal to obtain a second mixed echo signal, splice the first N signals of the second echo signal and the second mixed echo signal to obtain a target echo signal; where N is the number of sampling points corresponding to the emission time interval.

2. The method for processing double - pulse blind - area signals applied to lidar according to claim 1, characterized in that, after splicing the first N signals of the second echo signal and the second mixed echo signal to obtain a target echo signal, it includes: Determine the distance to the target object according to the target echo signal and the emission time interval.

3. The method for processing double - pulse blind - area signals applied to lidar according to claim 1, characterized in that, the capturing of the echo signals generated by the reflection of two detection pulses encountering a target object includes: Obtain the reflection signals generated by the reflection of the two detection pulses on the target object; Perform high - pass filtering on the reflection signals to obtain the echo signals.

4. The method for processing double - pulse blind - area signals applied to lidar according to claim 1, characterized in that, before delaying the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal, it includes: Multiply the echo signal by a preset compensation time signal to obtain a compensated echo signal.

5. The method for processing double - pulse signals applied to lidar according to claim 4, characterized in that, the delaying of the echo signal forward by a duration corresponding to the emission time interval to obtain a first echo signal includes: Delay the compensated echo signal forward by a duration corresponding to the emission time interval to obtain the first echo signal.

6. The method for processing double - pulse signals applied to lidar according to claim 4, characterized in that, the adding of N zeros to the tail of the echo signal to obtain a second echo signal includes: Add N zeros to the tail of the compensated echo signal to obtain the second echo signal.

7. The method for processing double - pulse blind - area signals applied to lidar according to claim 4, characterized in that, The compensation time signal is calculated based on the pulse width of the detection pulse, the duration corresponding to the emission time interval, and the time interval between the trailing edge of the first detection pulse and the leading edge of the second detection pulse. The first detection pulse and the second detection pulse are two detection pulses transmitted according to a preset emission time interval within one detection period.

8. A lidar, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, when the processor executes the computer program, the steps of the dual-pulse blind area signal processing method according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium storing a computer program, characterized in that, when the computer program is executed by a processor, the steps of the dual-pulse blind area signal processing method according to any one of claims 1 to 7 are implemented.

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