Method and device for eliminating range aliasing of lidar, equipment and storage medium

Abstract

The application discloses a laser radar distance aliasing elimination method and device, equipment and storage medium, relates to the technical field of laser radar, and comprises the following steps: emitting a detection signal pulse to a target object, so that a single photon sensing array receives a reflected echo signal pulse of the target object and feeds back; obtaining a plurality of detection distances based on the time of flight principle and the echo signal pulse; and determining the real distance of the target object from the plurality of detection distances according to the position information of the highest response point of the single photon sensing array. By adopting the technical means of combining the rotating mirror scanning structure and the single photon sensing array, the physical characteristics that the reflected light spots of different distance targets are offset in position on the sensing array due to the continuous rotation of the rotating mirror during the flight of the laser are utilized, the position information of the highest response point is taken as the judgment basis, and the distance aliasing problem caused by the time sequence ambiguity of the echo signal and the emission pulse when the single repetition frequency pulse laser radar is used for distance measurement is effectively solved.

Description

Technical Field

[0001] This application relates to the field of lidar technology, and in particular to lidar range aliasing elimination methods, apparatus, devices and storage media. Background Technology

[0002] In pulsed lidar ranging systems based on the time-of-flight principle, it is necessary to accurately determine the true distance corresponding to the echo signal pulse reflected from the target object in order to avoid the problem of multiple candidate values ​​in the distance measurement result due to the ambiguity of the periodic emission and reception timing of the laser pulse.

[0003] In existing technologies, multi-frequency modulation or variable-time interval laser pulse emission methods are commonly used to eliminate range aliasing. Multi-frequency modulation schemes require multiple lasers or modulation components with different modulation frequencies, leading to complex system structure and control logic, and high costs. Variable-time interval schemes, on the other hand, result in non-uniform variations in the laser pulse repetition frequency, causing inconsistent spatial distribution density of point cloud data and affecting sensing accuracy. Both of these existing methods struggle to completely eliminate range aliasing at a low cost while ensuring point cloud quality and uniformity.

[0004] Therefore, the urgent technical problem to be solved is: how to effectively distinguish multiple candidate distances generated by distance aliasing in a pulse lidar system with a single repetition frequency, without introducing additional frequency components or changing the uniformity of pulse emission, so as to accurately determine the true distance of the target object.

[0005] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The main objective of this application is to provide a method, apparatus, device, and storage medium for eliminating distance aliasing in lidar, aiming to solve the technical problem of how to effectively distinguish the true distance of a target object that cannot be accurately determined due to distance aliasing.

[0007] To achieve the above objectives, this application proposes a method for eliminating range aliasing in lidar, the method comprising: A detection signal pulse is emitted to the target object so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object; Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained; Obtain the location information of the highest response point of the single-photon sensing array; Based on the location information of the highest response point, the true distance of the target object is determined from the plurality of detection distances.

[0008] In one embodiment, the positional relationship between the laser, the rotating mirror, and the single-photon sensing array is configured such that the emitting optical path of the laser and the receiving optical path of the single-photon sensing array form a common optical path or quasi-common optical path structure through the rotating mirror; The transmission of a detection signal pulse to the target object, so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object, includes: Obtain the transmission frequency; Based on the emission frequency, the laser is controlled to emit detection signal pulses to the rotating mirror; The rotating mirror reflects the detection signal pulse to the target object, causing the target object to reflect the detection signal pulse and generate an echo signal pulse. The echo signal pulse is reflected by the rotating mirror to the single-photon sensing array, so that the single-photon sensing array receives the echo signal pulse and feeds it back.

[0009] In one embodiment, after transmitting a detection signal pulse to the target object so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object, the method further includes: Based on the single-photon sensing array, multiple single-photon sensing pixels are determined; The trigger events of each single-photon sensing pixel are obtained based on the echo signal pulses reflected by the target object received by the single-photon sensing array. The trigger events of each single-photon sensing pixel are counted to obtain the trigger count of each single-photon sensing pixel.

[0010] In one embodiment, the multiple detection distances obtained based on the time-of-flight principle and the echo signal pulse include: Based on the echo signal pulses, multiple candidate flight times are obtained; Based on the time-of-flight principle and the candidate flight times, multiple detection distances are obtained, and the candidate flight times correspond one-to-one with the detection distances.

[0011] In one embodiment, obtaining the location information of the highest response point of the single-photon sensing array includes: Obtain the trigger count of the single-photon sensing pixel of the single-photon sensing array; The highest response point is determined based on the number of triggers of each single-photon sensing pixel. Based on the highest response point, the location information of the highest response point is obtained.

[0012] In one embodiment, determining the true distance of the target object from the plurality of detection distances based on the location information of the highest response point includes: Obtain the preset distance-location mapping relationship; Based on the preset distance-location mapping relationship and the location information of the highest response point, the theoretical distance is determined; The theoretical distance is compared with each of the detection distances, and the true distance of the target object is obtained based on the comparison result.

[0013] In one embodiment, before obtaining the preset distance-location mapping relationship, the method further includes: Place the reflective object at multiple known distances; The laser, the single-photon sensing array, and the rotating mirror are controlled to measure the reflective objects at each known distance to obtain the position of the highest response point corresponding to each known distance. Based on each known distance and the location of the highest response point corresponding to each known distance, a preset distance-location mapping relationship is established.

[0014] Furthermore, to achieve the above objectives, this application also proposes a laser radar range aliasing elimination device, the laser radar range aliasing elimination device comprising: The scanning module is used to transmit a detection signal pulse to the target object so that the single-photon sensing array receives the echo signal pulse reflected by the target object and feeds it back. The detection module is used to obtain multiple detection distances based on the time-of-flight principle and the echo signal pulses; The calibration module is used to obtain the location information of the highest response point of the single-photon sensing array; The output module is used to determine the true distance of the target object from the plurality of detection distances based on the location information of the highest response point.

[0015] In addition, to achieve the above objectives, this application also proposes a lidar range aliasing elimination device, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the lidar range aliasing elimination method described above.

[0016] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the lidar range aliasing elimination method described above.

[0017] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the lidar range aliasing elimination method described above.

[0018] This application transmits a detection signal pulse to a target object, enabling a single-photon sensing array to receive and feed back the echo signal pulse reflected from the target object. Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained. The position information of the highest response point of the single-photon sensing array is acquired. Based on the position information of the highest response point, the true distance of the target object is determined from the multiple detection distances. This application employs a technique combining a rotating mirror scanning structure with a single-photon sensing array. It utilizes the physical characteristic that the continuous rotation of the mirror during laser flight causes the position of the reflected light spot from targets at different distances to shift on the sensing array. By using the position information of the highest response point as the judgment criterion, this application effectively solves the distance aliasing problem caused by the ambiguity between the echo signal and the transmitted pulse timing in single-repetition-frequency pulse lidar during ranging. While maintaining uniform laser pulse emission, it achieves aliasing elimination without increasing hardware costs using only a single-frequency laser and existing optical structures. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating an embodiment of the lidar range aliasing elimination method of this application. Figure 2 This is the emission optical path diagram provided in Embodiment 1 of the lidar range aliasing elimination method of this application; Figure 3 This is a reflection optical path diagram provided in Embodiment 1 of the lidar range aliasing elimination method of this application; Figure 4 This is an example diagram illustrating the range aliasing phenomenon provided in Embodiment 1 of the lidar range aliasing elimination method of this application; Figure 5 This is a schematic diagram of the module structure of the lidar range aliasing elimination device according to an embodiment of this application; Figure 6 This is a schematic diagram of the device structure of the hardware operating environment involved in the lidar range aliasing elimination method in the embodiments of this application.

[0022] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0023] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0024] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0025] The main solution of this application embodiment is: to transmit a detection signal pulse to the target object so that the single-photon sensing array receives the echo signal pulse reflected by the target object and feeds it back; to obtain multiple detection distances based on the time-of-flight principle and the echo signal pulse; to obtain the position information of the highest response point of the single-photon sensing array; and to determine the true distance of the target object from the multiple detection distances based on the position information of the highest response point.

[0026] In this embodiment, for ease of description, the controller of the lidar distance measurement system will be used as the execution subject in the following description.

[0027] Existing technologies often employ multi-frequency modulation or variable-time interval laser pulse emission to eliminate range aliasing. Multi-frequency modulation schemes require multiple lasers or modulation components with different modulation frequencies, leading to complex system structure and control logic, and high costs. Variable-time interval schemes, on the other hand, result in non-uniform variations in the laser pulse repetition frequency, causing inconsistent spatial distribution density of point cloud data and affecting sensing accuracy. Both of these existing methods struggle to achieve complete elimination of range aliasing at a low cost while maintaining point cloud quality and uniformity.

[0028] This application provides a solution that utilizes a combination of a rotating mirror scanning structure and a single-photon sensing array. By taking advantage of the physical characteristic that the continuous rotation of the rotating mirror during laser flight causes the position of the reflected light spot from targets at different distances to shift on the sensing array, the position information of the highest response point is used as the basis for judgment. This effectively solves the distance aliasing problem caused by the ambiguity between the echo signal and the timing of the emitted pulse in single-repetition-frequency pulse lidar during ranging. Under the premise of maintaining uniform laser pulse emission, the aliasing elimination effect is achieved without increasing hardware costs by using only a single-frequency laser and existing optical structures.

[0029] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device capable of performing the above functions, such as a controller of a lidar distance measurement system. The following description uses a lidar distance measurement system controller as an example to illustrate this embodiment and the subsequent embodiments.

[0030] Based on this, this application provides a lidar distance measurement method, which is applied to a lidar distance measurement system. The lidar distance measurement system includes a laser, a single-photon sensing array, and a rotating mirror. The positional relationship between the laser, the rotating mirror, and the single-photon sensing array is configured such that the emission optical path of the laser and the receiving optical path of the single-photon sensing array form a common or quasi-common optical path structure through the rotating mirror. The laser emits pulse signals to the rotating mirror at a fixed frequency, and the rotating mirror rotates continuously, reflecting the pulse signals to scan the target object. The rotating mirror is configured to rotate continuously during the laser's flight time, so that the echo signals reflected by target objects at different distances form different light spot positions on the single-photon sensing array. The single-photon sensing array is a semiconductor sensor chip capable of detecting single-photon level optical signals, which is composed of a large number of single-photon avalanche diode pixels arranged in an array.

[0031] Reference Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the lidar range aliasing elimination method of this application.

[0032] In this embodiment, the lidar range aliasing elimination method includes steps S10 to S40: Step S10: Transmit a detection signal pulse to the target object so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object; It should be noted that the detection signal pulse is a short, high-intensity light pulse emitted by the laser, used to detect the distance information of a target object. The target object refers to any reflective surface within the detection range of the lidar, such as vehicles, pedestrians, or obstacles. The echo signal pulse is the light signal returned after the detection signal pulse is reflected by the target object.

[0033] It is understandable that, since ranging systems based on the pulse time-of-flight principle need to actively transmit detection signals and receive their echoes to calculate distances, performing step S10 can avoid the problem of passive detection methods being greatly affected by ambient light, thereby improving the initiative and anti-interference capability of the ranging system.

[0034] In one feasible implementation, step S10 may include: acquiring the emission frequency; controlling the laser to emit a detection signal pulse to the rotating mirror based on the emission frequency; reflecting the detection signal pulse to the target object through the rotating mirror, so that the target object reflects the detection signal pulse and generates an echo signal pulse; reflecting the echo signal pulse to the single-photon sensing array through the rotating mirror, so that the single-photon sensing array receives the echo signal pulse and provides feedback.

[0035] It should be noted that the emission frequency refers to the repetition frequency of the detection pulse emitted by the laser per unit time.

[0036] For example, such as Figure 2 As shown, the laser emits a laser pulse, which is reflected by a prism mirror and then directed toward the reflecting object. The reflected light (target object) is reflected by the same mirror to the SPAD (Single Photon Avalanche Diode) chip, completing the optical path process of transmitting and receiving.

[0037] In this embodiment, by controlling the transmission frequency and using a rotating mirror to achieve scanning and reception, the problem that a single fixed optical path cannot achieve area array detection is solved, and point-by-point scanning and distance measurement of a large-scale scene are realized.

[0038] In one feasible implementation, step S10 may include: determining multiple single-photon sensing pixels based on the single-photon sensing array; obtaining trigger events for each single-photon sensing pixel based on the echo signal pulses reflected by the target object received by the single-photon sensing array; and counting the trigger events for each single-photon sensing pixel to obtain the trigger count for each single-photon sensing pixel.

[0039] It should be noted that a single-photon sensing pixel is the smallest photosensitive unit in a single-photon sensing array, capable of responding to a single photon event. A trigger event refers to the electrical signal response generated by a pixel when it detects a photon. The trigger count refers to the cumulative number of times each pixel is triggered within a certain time window.

[0040] For example, such as Figure 3 As shown, since light travels for a period of time, the rotating mirror rotates through an angle during this time. The echo signal pulses reflected by target objects (reflector 1, reflector 2) at different distances are reflected by the rotating mirror and form light spots at different positions on the SPAD chip. The center position of the light spot (the highest response point) can be determined by counting the number of triggers of each pixel.

[0041] In this embodiment, by counting the number of triggers for each pixel and determining the highest response point, the distance blurring problem of the traditional TOF method in the case of multiple echoes is solved, providing key positional information for subsequent distance dealiasing.

[0042] The above are merely feasible implementations of step S10 provided in this embodiment. This embodiment does not specifically limit the specific implementation of step S10.

[0043] Step S20: Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained; It should be noted that the time-of-flight principle refers to a ranging method that calculates distance by measuring the time difference between the transmission and reception of a light pulse. The detection range refers to the set of possible distance values ​​calculated based on the time-of-flight principle.

[0044] It is understandable that, due to the periodic emission characteristics of laser pulses, when the target distance exceeds the maximum unambiguous distance, a single echo signal may correspond to multiple possible flight times. Therefore, performing step S20 can avoid distance judgment errors caused by directly using a single measurement value, thereby improving the system's ability to detect distant targets.

[0045] In one feasible implementation, step S20 may include: obtaining multiple candidate flight times based on the echo signal pulse; obtaining multiple detection distances based on the time-of-flight principle and each of the candidate flight times, wherein the candidate flight times and the detection distances correspond one-to-one.

[0046] It should be noted that candidate flight time refers to the possible flight time values ​​of the echo signal relative to different transmitted pulses, and its number is determined by the maximum detection range designed for the system.

[0047] For example, such as Figure 4 As shown, when the interval between transmitted pulse 1 and transmitted pulse 2 is T, the received reflected pulse (echo signal pulse) may correspond to two candidate flight times: t (corresponding to transmitted pulse 1) and t+T (corresponding to transmitted pulse 2). Based on these two candidate flight times, two detection distances can be calculated.

[0048] In this embodiment, by establishing the correspondence between candidate flight times and detection distances, the problem of a single echo signal corresponding to multiple possible distances is solved, providing a data foundation for subsequent determination of the true distance based on location information.

[0049] The above are merely feasible implementations of step S20 provided in this embodiment. This embodiment does not specifically limit the specific implementation of step S20.

[0050] Step S30: Obtain the location information of the highest response point of the single-photon sensing array; It should be noted that the highest response point refers to the pixel in a single-photon sensing array that responds most strongly to the same echo signal within a specific time window; it is typically the pixel that is triggered the most times. Location information refers to the coordinates or pixel index of this highest response point on the single-photon sensing array.

[0051] It is understandable that since the echo signals reflected by target objects at different distances will fall on different positions of the single-photon sensing array due to the rotation of the rotating mirror during the laser flight time, performing step S30 can avoid the distance ambiguity caused by relying solely on flight time information, thereby providing key spatial location basis for subsequent accurate determination of the true distance.

[0052] In one feasible implementation, step S30 may include: obtaining the trigger count of the single-photon sensing pixels of the single-photon sensing array; determining the highest response point based on the trigger count of each single-photon sensing pixel; and obtaining the position information of the highest response point based on the highest response point.

[0053] For example, such as Figure 4 As shown, when the reflected pulse is received, SPAD pixel 4 (single-photon sensing pixel) is triggered the most times in multiple samplings, indicating that this position is the energy center of the light spot, that is, the highest response point, and its position information is the coordinates of pixel 4.

[0054] In this embodiment, by identifying and locating the highest response point, the problem of distance attribution ambiguity caused by pulse period repetition in the traditional TOF method is solved, providing a reliable position discrimination feature for achieving non-aliasing distance measurement.

[0055] The above are merely feasible implementations of step S30 provided in this embodiment. This embodiment does not specifically limit the specific implementation of step S30.

[0056] Step S40: Based on the location information of the highest response point, determine the true distance of the target object from the plurality of detection distances.

[0057] It should be noted that the true distance of the target object refers to the actual physical distance between the target object and the lidar, which is the only correct distance value after eliminating the influence of distance aliasing.

[0058] It is understandable that, since there is a definite mapping relationship between the location information of the highest response point and the actual distance of the target object, and only one of the multiple detection distances matches the distance determined by the location information, performing step S40 can avoid the ambiguity of distance attribution caused by the repetition of the pulse cycle, thereby improving the accuracy and reliability of distance measurement.

[0059] In one feasible implementation, step S40 may include: obtaining a preset distance-position mapping relationship; determining a theoretical distance based on the preset distance-position mapping relationship and the position information of the highest response point; comparing the theoretical distance with each of the detection distances, and obtaining the true distance of the target object based on the comparison result.

[0060] It should be noted that the preset distance-location mapping relationship refers to the one-to-one correspondence between the location of the highest response point and the actual distance, established through system calibration. The theoretical distance refers to the distance estimate obtained by querying the preset distance-location mapping relationship based on the location information of the highest response point.

[0061] For example, when the highest response point is located at SPAD pixel 4, the query mapping relationship yields a theoretical distance of 50 meters; this theoretical distance is compared with multiple detection distances (such as 50 meters, 200 meters), and the 50-meter distance that matches is determined as the true distance.

[0062] Specifically, before obtaining the preset distance-position mapping relationship, the method further includes: placing the reflector at multiple known distances; controlling the laser, the single-photon sensing array, and the rotating mirror to measure the reflector at each known distance to obtain the position of the highest response point corresponding to each known distance; and establishing the preset distance-position mapping relationship based on each known distance and the position of the highest response point corresponding to each known distance.

[0063] It should be noted that the reflective object refers to an object with known reflective properties used in the system calibration process. The known distance refers to the actual distance between the reflective object and the lidar, which is accurately measured during the calibration process.

[0064] For example, during the calibration process, the standard reflector is placed at known distances such as 10 meters, 50 meters, and 100 meters, and the position of the highest response point (such as pixel 1, pixel 3, and pixel 5) corresponding to each distance is recorded, thereby establishing a distance-position mapping database.

[0065] In this embodiment, by introducing location information as an independent discrimination dimension and cross-validating it with time-of-flight information, the problem that multiple candidate distances cannot be distinguished by relying solely on time measurement is solved, and the complete elimination of distance aliasing is achieved under a single transmission frequency.

[0066] The above are merely feasible implementations of step S40 provided in this embodiment. This embodiment does not specifically limit the specific implementation of step S40.

[0067] This embodiment provides a method for eliminating range aliasing in lidar. A detection signal pulse is emitted to the target object, allowing a single-photon sensing array to receive and feed back the echo signal pulse reflected from the target object. Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained. The position information of the highest response point of the single-photon sensing array is acquired. Based on the position information of the highest response point, the true distance of the target object is determined from the multiple detection distances. This application utilizes a technique combining a rotating mirror scanning structure and a single-photon sensing array. It leverages the physical characteristic that the continuous rotation of the mirror during laser flight causes the position of the reflected light spot from targets at different distances to shift on the sensing array. By using the position information of the highest response point as the judgment criterion, it effectively solves the range aliasing problem caused by the ambiguity between the echo signal and the emitted pulse timing in single-repetition-frequency pulse lidar. While maintaining uniform laser pulse emission, it achieves aliasing elimination without increasing hardware costs using only a single-frequency laser and existing optical structures.

[0068] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the lidar range aliasing elimination method of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0069] This application also provides a lidar range aliasing elimination device; please refer to... Figure 5 The lidar range aliasing elimination device includes: The scanning module 10 is used to transmit a detection signal pulse to the target object so that the single-photon sensing array receives the echo signal pulse reflected by the target object and feeds it back. Detection module 20 is used to obtain multiple detection distances based on the time-of-flight principle and the echo signal pulse; Calibration module 30 is used to obtain the position information of the highest response point of the single-photon sensing array; The output module 40 is used to determine the true distance of the target object from the plurality of detection distances based on the location information of the highest response point.

[0070] The lidar range aliasing elimination device provided in this application, employing the lidar range aliasing elimination method in the above embodiments, can solve the technical problem of lidar range aliasing elimination. Compared with the prior art, the beneficial effects of the lidar range aliasing elimination device provided in this application are the same as those of the lidar range aliasing elimination method provided in the above embodiments, and other technical features in the lidar range aliasing elimination device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0071] The scanning module 10 is further configured to acquire the emission frequency; control the laser to emit a detection signal pulse to the rotating mirror based on the emission frequency; reflect the detection signal pulse to the target object through the rotating mirror, so that the target object reflects the detection signal pulse and generates an echo signal pulse; reflect the echo signal pulse to the single-photon sensing array through the rotating mirror, so that the single-photon sensing array receives the echo signal pulse and provides feedback.

[0072] The scanning module 10 is further configured to determine multiple single-photon sensing pixels based on the single-photon sensing array; obtain the trigger events of each single-photon sensing pixel based on the echo signal pulses reflected by the target object received by the single-photon sensing array; and count the trigger events of each single-photon sensing pixel to obtain the trigger count of each single-photon sensing pixel.

[0073] The detection module 20 is further configured to: obtain multiple candidate flight times based on the echo signal pulse; and obtain multiple detection distances based on the flight time principle and each of the candidate flight times, wherein the candidate flight times and the detection distances correspond one-to-one.

[0074] The calibration module 30 is further configured to: obtain the trigger count of the single-photon sensing pixels of the single-photon sensing array; determine the highest response point based on the trigger count of each single-photon sensing pixel; and obtain the position information of the highest response point based on the highest response point.

[0075] The output module 40 is further configured to acquire a preset distance-position mapping relationship; determine the theoretical distance based on the preset distance-position mapping relationship and the position information of the highest response point; compare the theoretical distance with each of the detection distances, and obtain the true distance of the target object based on the comparison result.

[0076] The output module 40 is also used to place the reflector at multiple known distances; control the laser, the single-photon sensing array and the rotating mirror to measure the reflector at each known distance to obtain the position of the highest response point corresponding to each known distance; and establish a preset distance-position mapping relationship based on each known distance and the position of the highest response point corresponding to each known distance.

[0077] This application provides a lidar range aliasing elimination device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the lidar range aliasing elimination method in the first embodiment described above.

[0078] The following is for reference. Figure 6 This document illustrates a structural schematic diagram of a lidar range aliasing cancellation device suitable for implementing embodiments of this application. The lidar range aliasing cancellation device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 6 The lidar anti-aliasing device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments of this application.

[0079] like Figure 6 As shown, the lidar range aliasing cancellation device may include a processing unit 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in ROM (Read Only Memory) 1002 or a program loaded from storage device 1003 into random access memory (RRAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the lidar range aliasing cancellation device. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1006: input devices 1007 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1008 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1003 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1009. Communication device 1009 allows the lidar range aliasing cancellation device to communicate wirelessly or wiredly with other devices to exchange data. Although lidar range aliasing cancellation devices with various systems are shown in the figures, it should be understood that it is not required to implement or possess all of the systems shown. More or fewer systems can be implemented alternatively.

[0080] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0081] The lidar distance aliasing elimination device provided in this application, employing the lidar distance aliasing elimination method in the above embodiments, can solve the technical problem of lidar distance aliasing elimination. Compared with the prior art, the beneficial effects of the lidar distance aliasing elimination device provided in this application are the same as those of the lidar distance aliasing elimination method provided in the above embodiments, and other technical features in this lidar distance aliasing elimination device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0082] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0083] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0084] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the lidar range aliasing elimination method in the above embodiments.

[0085] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0086] The aforementioned computer-readable storage medium may be included in the lidar range aliasing elimination device; or it may exist independently and not be assembled into the lidar range aliasing elimination device.

[0087] The aforementioned computer-readable storage medium carries one or more programs that, when executed by a lidar range aliasing cancellation device, cause the lidar range aliasing cancellation device to: emit a detection signal pulse to a target object, so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object; obtain multiple detection distances based on the time-of-flight principle and the echo signal pulse; acquire the position information of the highest response point of the single-photon sensing array; and determine the true distance of the target object from the multiple detection distances based on the position information of the highest response point.

[0088] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0089] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0090] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0091] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the above-described lidar range aliasing elimination method, thereby solving the technical problem of lidar range aliasing elimination. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the lidar range aliasing elimination method provided in the above embodiments, and will not be repeated here.

[0092] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the lidar range aliasing elimination method described above.

[0093] The computer program product provided in this application can solve the technical problem of eliminating range aliasing in lidar. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the lidar range aliasing elimination method provided in the above embodiments, and will not be repeated here.

[0094] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for eliminating range aliasing in lidar, characterized in that, The method is applied to a lidar distance measurement system, which includes a laser, a single-photon sensing array, and a rotating mirror. The positional relationship between the laser, the rotating mirror, and the single-photon sensing array is configured such that the emission path of the laser and the receiving path of the single-photon sensing array form a common or quasi-common optical path structure through the rotating mirror. The method includes: A detection signal pulse is emitted to the target object so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object; Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained; Obtain the location information of the highest response point of the single-photon sensing array, wherein the highest response point is the pixel point in the single-photon sensing array that responds most strongly to the same echo signal within a specific time window; Based on the location information of the highest response point, the true distance of the target object is determined from the plurality of detection distances; The transmission of a detection signal pulse to the target object, so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object, includes: Obtain the transmission frequency; Based on the emission frequency, the laser is controlled to emit detection signal pulses to the rotating mirror; The rotating mirror reflects the detection signal pulse to the target object, causing the target object to reflect the detection signal pulse and generate an echo signal pulse. The echo signal pulse is reflected by the rotating mirror to the single-photon sensing array, so that the single-photon sensing array receives the echo signal pulse and feeds it back.

2. The method as described in claim 1, characterized in that, After transmitting a detection signal pulse to the target object, so that the single-photon sensing array receives and feeds back the echo signal pulse reflected by the target object, the method further includes: Based on the single-photon sensing array, multiple single-photon sensing pixels are determined; The trigger events of each single-photon sensing pixel are obtained based on the echo signal pulses reflected by the target object received by the single-photon sensing array. The trigger events of each single-photon sensing pixel are counted to obtain the trigger count of each single-photon sensing pixel.

3. The method as described in claim 1, characterized in that, Based on the time-of-flight principle and the echo signal pulse, multiple detection distances are obtained, including: Based on the echo signal pulses, multiple candidate flight times are obtained; Based on the time-of-flight principle and the candidate flight times, multiple detection distances are obtained, and the candidate flight times correspond one-to-one with the detection distances.

4. The method as described in claim 1, characterized in that, The step of obtaining the location information of the highest response point of the single-photon sensing array includes: Obtain the trigger count of the single-photon sensing pixel of the single-photon sensing array; The highest response point is determined based on the number of triggers of each single-photon sensing pixel. Based on the highest response point, the location information of the highest response point is obtained.

5. The method as described in claim 1, characterized in that, Determining the true distance of the target object from the plurality of detection distances based on the location information of the highest response point includes: Obtain the preset distance-location mapping relationship; Based on the preset distance-location mapping relationship and the location information of the highest response point, the theoretical distance is determined; The theoretical distance is compared with each of the detection distances, and the true distance of the target object is obtained based on the comparison result.

6. The method as described in claim 5, characterized in that, Before obtaining the preset distance-location mapping relationship, the method further includes: Place the reflective object at multiple known distances; The laser, the single-photon sensing array, and the rotating mirror are controlled to measure the reflective objects at each known distance to obtain the position of the highest response point corresponding to each known distance. Based on each known distance and the location of the highest response point corresponding to each known distance, a preset distance-location mapping relationship is established.

7. A laser radar range aliasing elimination device, characterized in that, The device includes: The scanning module is used to transmit a detection signal pulse to the target object so that the single-photon sensing array receives the echo signal pulse reflected by the target object and feeds it back. The detection module is used to obtain multiple detection distances based on the time-of-flight principle and the echo signal pulses; The calibration module is used to obtain the location information of the highest response point of the single-photon sensing array, wherein the highest response point is the pixel point in the single-photon sensing array that responds most strongly to the same echo signal within a specific time window. The output module is used to determine the true distance of the target object from the plurality of detection distances based on the location information of the highest response point; The scanning module is further configured to acquire the emission frequency; control the laser to emit a detection signal pulse to the rotating mirror based on the emission frequency; reflect the detection signal pulse to the target object through the rotating mirror, so that the target object reflects the detection signal pulse and generates an echo signal pulse; reflect the echo signal pulse to the single-photon sensing array through the rotating mirror, so that the single-photon sensing array receives the echo signal pulse and provides feedback.

8. A laser radar range aliasing elimination device, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the lidar range aliasing elimination method as described in any one of claims 1 to 6.

9. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the lidar range aliasing elimination method as described in any one of claims 1 to 6.

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