Ranging Method, Ranging Device, Ranging Equipment and Storage Medium

Abstract

Embodiments of the present application are applicable to the field of ranging technology, and provide a ranging method, a ranging device, a ranging equipment, and a storage medium. The ranging method includes: sequentially transmitting 2n encoded pulse signals modulated in a target pulse signal to an object to be measured, and sequentially receiving each returned encoded pulse signal to respectively generate an original histogram having an avalanche count peak; according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, sequentially superimposing the avalanche count peaks corresponding to every n encoded pulse signals respectively to obtain a first superimposed histogram and a second superimposed histogram; performing interference removal processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal; determining the interval distance from the object to be measured according to the target interference-free histogram. By using the above method, the ranging time and power consumption required for measuring the distance of a relatively far object to be measured can be reduced.

Description

Technical Field

[0001] This application belongs to the technical field of distance measurement, and particularly relates to a distance measurement method, a distance measurement device, a distance measurement equipment, and a storage medium. Background Art

[0002] The Time Of Flight (TOF) method can emit a pulsed signal light beam towards an object to be measured, and based on a single photon detector (for example, a single photon avalanche photodiode), capture the photon pulse signal returning to generate an avalanche generation histogram. Then, calculate the distance to the object to be measured according to the peak in the statistically obtained histogram.

[0003] Currently, in order to measure the distance of a relatively far object to be measured, it is usually necessary to continuously emit pulsed signal light beams with a high peak optical power towards the object to be measured multiple times. Then, superimpose the statistically obtained multiple histograms to increase the photon signal intensity. For example, continuously emit pulsed signal light beams with a high peak optical power towards the object to be measured 4 times.

[0004] However, in order to avoid interference between the received photon pulse signals, a relatively long interval duration is required between two adjacent emissions of the pulsed signal light beam. Furthermore, when measuring the distance of a relatively far object to be measured, it not only consumes more distance measurement time, but also requires more power consumption. Summary of the Invention

[0005] The embodiments of this application provide a distance measurement method, a distance measurement device, a distance measurement equipment, and a storage medium, which can solve the problem that when measuring the distance of a relatively far object to be measured, it not only consumes more distance measurement time, but also requires more power consumption.

[0006] In a first aspect, the embodiments of this application provide a distance measurement method, and the method includes:

[0007] Sequentially emit 2n encoded pulse signals in the target pulse signal that have been modulated to an object to be measured, and sequentially receive each returned encoded pulse signal to respectively generate an original histogram with an avalanche count peak; the emission interval duration between each encoded pulse signal is different; n is an integer greater than or equal to 2;

[0008] According to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, sequentially superimpose the avalanche count peaks corresponding to every n encoded pulse signals respectively to obtain a first superimposed histogram and a second superimposed histogram; the first superimposed histogram is obtained by superimposing the avalanche count peaks from the 1st to the nth in the generation order; the second superimposed histogram is obtained by superimposing the avalanche count peaks from the (n + 1)th to the 2nth in the generation order;

[0009] Perform interference removal processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal;

[0010] Determine the interval distance from the object to be measured according to the target interference-free histogram.

[0011] In a second aspect, an embodiment of the present application provides a ranging device, which includes:

[0012] An execution module, configured to sequentially transmit 2n encoded pulse signals modulated in the target pulse signal to the object to be measured, and sequentially receive each returned encoded pulse signal to respectively generate a raw histogram with an avalanche count peak; the transmission interval duration between each encoded pulse signal is different; n is an integer greater than or equal to 2;

[0013] A superimposing module, configured to sequentially superimpose the avalanche count peaks corresponding to every n encoded pulse signals respectively according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, to obtain a first superimposed histogram and a second superimposed histogram; the first superimposed histogram is obtained by superimposing the avalanche count peaks from the 1st to the nth in the generation order; the second superimposed histogram is obtained by superimposing the avalanche count peaks from the (n + 1)th to the 2nth in the generation order;

[0014] A generation module, configured to perform interference removal processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal;

[0015] A ranging module, configured to determine the interval distance from the object to be measured according to the target interference-free histogram.

[0016] In a third aspect, an embodiment of the present application provides a ranging device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method in the first aspect as described above is implemented.

[0017] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the method in the first aspect as described above is implemented.

[0018] In a fifth aspect, an embodiment of the present application provides a computer program product. When the computer program product runs on a ranging device, the ranging device is enabled to execute the method in the first aspect as described above.

[0019] The beneficial effects of the embodiments of the present application compared with the prior art are as follows: The ranging device can sequentially transmit coded pulse signals to the object to be measured according to the transmission interval duration between 2n coded pulse signals in the target pulse signal, and receive the original histograms with avalanche count peaks generated by each returned coded pulse signal. Among them, n needs to be greater than or equal to 2. Then, according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, the avalanche count peaks corresponding to the 1st to nth coded pulse signals are sequentially superimposed, and the avalanche count peaks corresponding to the (n + 1)th to 2nth coded pulse signals are superimposed to obtain a first superimposed histogram and a second superimposed histogram. Since the transmission interval duration between any two adjacent coded pulse signals among the modulated 2n coded pulse signals is different. Therefore, when superimposing two avalanche count peaks in the original histogram according to the corresponding transmission interval duration (that is, the generation order of the avalanche count peaks), each avalanche count peak formed by the optical signal returned by the object to be measured can also be superimposed based on the corresponding transmission interval duration. That is, in the first superimposed histogram and the second superimposed histogram, the n avalanche count peaks corresponding to the object to be measured are enhanced. However, since the avalanche count peaks (interference peaks) formed by the optical signals returned by multiple other non-object-to-be-measured in the original histogram are not spaced at the specially set transmission interval duration. Therefore, the avalanche count peaks corresponding to the non-object-to-be-measured cannot be superimposed based on the above transmission interval duration. That is, in the first superimposed histogram and the second superimposed histogram, the avalanche count peaks corresponding to the non-object-to-be-measured cannot be enhanced. Therefore, the interference caused by the avalanche count peaks of the non-object-to-be-measured to the avalanche count peaks of the object to be measured can be reduced. Based on this, the ranging device can perform interference removal based on the first superimposed histogram and the second superimposed histogram corresponding to the enhanced avalanche count peaks to obtain a target interference-free histogram, and accurately determine the interval distance from the object to be measured according to the target interference-free histogram. And, during the ranging process, encoding n coded pulse signals into a group of pulse signal beams for ranging can evenly distribute the peak power in an original pulse signal to 2n coded pulse signals. Furthermore, the requirement for the peak optical power of the light source and the power consumption are reduced. And, since the transmission interval duration between any two adjacent coded pulse signals among the modulated 2n coded pulse signals is different, the interference between avalanche count peaks can be avoided. Therefore, the transmission interval duration between two adjacent transmissions of coded pulse signals does not need to be set with a long interval duration. Furthermore, when the distance of the object to be measured that can be measured is far, the ranging time required can also be reduced. That is, in the case of limited ranging time and peak light source power, a farther ranging performance can also be obtained. Description of the Drawings

[0020] 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 drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a flowchart of the implementation of a ranging method provided by an embodiment of the present application;

[0022] Figure 2 It is a schematic diagram of the coding structure of the target pulse signal in a ranging method provided by an embodiment of the present application;

[0023] Figure 3 It is a schematic diagram of the structure of a histogram in a ranging method provided by an embodiment of the present application;

[0024] Figure 4 It is a schematic diagram of an implementation manner of generating the first superimposed histogram and the second superimposed histogram in a ranging method provided by an embodiment of the present application;

[0025] Figure 5 It is a schematic diagram of the application scenario of superimposing the avalanche count peak in a ranging method provided by an embodiment of the present application;

[0026] Figure 6 It is a schematic diagram of the application scenario of the target interference-free histogram in a ranging method provided by an embodiment of the present application;

[0027] Figure 7 It is a schematic diagram of the application scenario of the first superimposed histogram and the second superimposed histogram in a ranging method provided by an embodiment of the present application;

[0028] Figure 8 It is a schematic diagram of the application scenario of the target interference-free histogram in a ranging method provided by another embodiment of the present application;

[0029] Figure 9 It is a schematic diagram of the structure of a ranging device provided by an embodiment of the present application;

[0030] Figure 10 It is a schematic diagram of the structure of a ranging device provided by an embodiment of the present application. Detailed implementation manners

[0031] 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 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.

[0032] It should be understood that when used in the specification of the present application and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0033] In addition, in the description of the specification of the present application and the appended claims, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0034] The time-of-flight method can generate an avalanche generation histogram by emitting a pulsed signal light beam towards the object to be measured and capturing the returned photon pulsed signal based on a single-photon detector (e.g., a single-photon avalanche photodiode). Then, the distance to the object to be measured is calculated according to the peak in the statistically obtained histogram.

[0035] Currently, in order to measure the distance to a relatively distant object to be measured, it is usually necessary to continuously emit pulsed signal light beams with a high peak optical power towards the object to be measured multiple times. Then, the statistically obtained multiple histograms are superimposed to increase the photon signal intensity. For example, pulsed signal light beams with a high peak optical power are continuously emitted towards the object to be measured 4 times.

[0036] However, in order to avoid interference between the received photon pulsed signals, a relatively long interval duration is required between two adjacent emissions of the pulsed signal light beam. As a result, when measuring the distance to a relatively distant object to be measured, not only does it take more ranging time, but also more power consumption is required.

[0037] Based on this, in order to be able to reduce the ranging time required when measuring the distance to a relatively distant object to be measured, the embodiments of the present application provide a ranging method, which can be applied to a ranging device. For example, a time-of-flight sensor, and the specific type of the ranging device is not limited in the embodiments of the present application.

[0038] Please refer to Figure 1 , Figure 1 which shows a flowchart of the implementation of a ranging method provided by the embodiments of the present application. The ranging method includes the following steps:

[0039] S101. Sequentially transmit 2n modulated coded pulse signals in the target pulse signal to the object to be measured, and sequentially receive each returned coded pulse signal to generate an original histogram with an avalanche count peak respectively.

[0040] In one embodiment, the above-mentioned transmission interval duration can be set according to the actual scenario, and there is no limitation thereto. It should be particularly noted that when setting the transmission interval duration, the transmission interval durations between each coded pulse signal should be different from each other. And, the above-mentioned n is an integer greater than or equal to 2. For the convenience of explanation, in this embodiment, n is taken as 2 for subsequent description. The object to be measured includes, but is not limited to, people, animals or static obstacles, and there is no limitation thereto.

[0041] It should be noted that when the ranging device sequentially transmits coded pulse signals to the object to be measured, the generation order of the avalanche count peaks generated in the original histogram is also the same as the transmission order of the coded pulse signals. In the embodiment of the present application, only the example that the ranging device transmits coded pulse signals to the object to be measured at a preset azimuth in the detection space is used for illustration, and the preset azimuth can be any detection direction in the detection space.

[0042] As an example, refer to Figure 2 , Figure 2 which is a schematic diagram of the coding structure of the target pulse signal in a ranging method provided by an embodiment of the present application. Exemplarily, Figure 2 may include 4 coded pulses a1, a2, a3, a4, and the transmission interval durations between every two adjacent coded pulse signals can be different. For example, the transmission interval duration between a1 and a2 can be 47 ns, the transmission interval duration between a2 and a3 can be 67 ns, and the transmission interval duration between a3 and a4 can be 87 ns.

[0043] Refer to Figure 3 , Figure 3 which is a schematic diagram of the structure of the histogram in a ranging method provided by an embodiment of the present application. Among them, Figure 3 the abscissa of the histogram in Figure 3 is time, and the ordinate is the avalanche count. Figure 3 Figure 3 includes avalanche count peaks generated by two kinds of target pulse signals. And, the highest red avalanche count peak is formed by the superposition of two different red avalanche count peaks. Therefore, in ​

[0044] S102. According to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, successively superimpose the avalanche count peaks corresponding to every n coded pulse signals respectively to obtain a first superimposed histogram and a second superimposed histogram.

[0045] In one embodiment, the above generation order has been explained and will not be elaborated here. It can be understood that the above generation interval duration is the emission interval duration in step S101.

[0046] It should be noted that all 2n avalanche count peaks are located in the original histogram. Therefore, according to the generation order, the avalanche count peaks from the 1st to the nth in the generation order can be successively superimposed to obtain a first superimposed histogram, and the avalanche count peaks from the (n + 1)th to the 2nth in the generation order can be superimposed to obtain a second superimposed histogram.

[0047] Optionally, referring to Figure 4 , the ranging device can superimpose the 2n avalanche count peaks according to steps S401 - S403 as shown in Figure 4 as follows:

[0048] S401. According to the target interval duration corresponding to the first avalanche count peak and the adjacent second avalanche count peak, shift each avalanche count peak in the original histogram by the target interval duration to obtain a shifted histogram with shifted avalanche count peaks.

[0049] S402. Superimpose the avalanche count peaks at the same time in the original histogram and the shifted histogram to obtain an initial superimposed histogram.

[0050] In one embodiment, the above first avalanche count peak is the avalanche count peak to be superimposed currently, and the generation order of the avalanche count peaks is known. Therefore, when determining the first avalanche count peak, the second avalanche count peak will also be a known avalanche count peak. Also, the target interval duration will be correspondingly determined. And the initial superimposed histogram contains the superimposed avalanche count peak formed by superimposing the first avalanche count peak and the second avalanche count peak.

[0051] Exemplarily, according to the generation order, when superimposing for the first time, the first avalanche count peak should be the first generated avalanche count peak, and the second avalanche count peak should be the second avalanche count peak.

[0052] As an example, taking the number of avalanche count peaks as 4 and generating the first superimposed histogram as an example. Referring to Figure 5 , Figure 5Schematic diagram of an application scenario of superimposing avalanche count peaks in a distance measurement method provided in an embodiment of the present application. Figure 5 In the A1, B1, and H1 parts, A1 is the original histogram, which includes avalanche count peaks generated by 4 coded pulse signals, namely b1, b2, b3, and b4. Among them, when the avalanche count peaks of b1 and b2 are superimposed, all avalanche count peaks in the original histogram can be moved forward by the generation interval between b1 and b2 to obtain a shifted histogram B1 with shifted avalanche count peaks. At this time, the avalanche count peak b1 in the original histogram will be at the same time as the avalanche count peak b2 in the shifted histogram. Based on this, after superimposing the avalanche count peaks at the same time in the original histogram and the shifted histogram, the initial superimposed histogram H1 obtained will contain the superimposed avalanche count peak b12 formed by the avalanche count peak b1 and the avalanche count peak b2.

[0053] based on Figure 5 It can be seen that, because the transmission interval duration between two adjacent coded pulse signals is different, the generation interval duration between any two adjacent avalanche count peaks is also different. Based on this, it can be understood that when shifting and superimposing according to the target interval duration corresponding to the first avalanche count peak and the second avalanche count peak, usually only the first avalanche count peak and the second avalanche count peak are at the same time. Furthermore, when the original histogram receives avalanche count peaks generated by multiple echo signals (including interference peaks generated by coded pulse signals returned by other non-test objects), the above steps can be used to better enhance the avalanche count peak generated by the coded pulse signal returned by the test object, and suppress the avalanche count peak corresponding to the interfering echo signal.

[0054] S403, taking the initial superimposed histogram as a new original histogram, and superimposing the avalanche count peak as a new first avalanche count peak, repeating the steps of obtaining the shifted histogram and the initial superimposed histogram, until the avalanche count peaks corresponding to every n coded pulse signals are superimposed respectively, to obtain a first superimposed histogram and a second superimposed histogram.

[0055] In one embodiment, since the superimposed avalanche count peak value is formed by superimposing the first avalanche count peak value and the second avalanche count peak value, when the superimposed avalanche count peak value is used as the new first avalanche count peak value, the third avalanche count peak value will be the adjacent second avalanche count peak value.

[0056] However, it should be noted that after the shift histogram is obtained, the shift histogram may include two third avalanche count peaks. Figure 5, there will be two avalanche count peaks b3. However, the generation interval duration (target interval duration) between the second avalanche count peak and the third avalanche count peak is fixed.

[0057] Based on this, when repeating the above steps S401 and S402 with the initial superimposed histogram as the new original histogram and the superimposed avalanche count peak as the new first avalanche count peak, by shifting each avalanche count peak in the original histogram (initial superimposed histogram) based on the target interval duration, there will be only one third avalanche count peak b3 at the same time as the first avalanche count peak. For example, when Figure 5 taking the initial superimposed histogram H1 in

[0058] as the new original histogram and b12 as the first avalanche count peak, its second avalanche count peak will be b3 in the initial superimposed histogram H1. Furthermore, in the newly generated initial superimposed histogram, the first avalanche count peak will be formed by superimposing the first, second, and third corresponding avalanche count peaks respectively.

[0059] In addition, the method of superimposing the avalanche count peaks corresponding to the (n + 1)-th to 2n-th coded pulse signals to obtain the second superimposed histogram is similar to the above. Specifically, referring to Figure 5 the A2, B2, and H2 parts in

[0060] Exemplarily, when superimposing the avalanche count peaks of bn+1 and bn+2, all the avalanche count peaks in the original histogram can be shifted forward by the generation interval duration between bn+1 and bn+2 to obtain a shifted histogram B2 with shifted avalanche count peaks. At this time, the avalanche count peak bn+1 in the original histogram will be at the same time as the avalanche count peak bn+2 in the shifted histogram. Based on this, after superimposing the avalanche count peaks at the same time in the original histogram and the shifted histogram, the initial superimposed histogram H2 will contain a superimposed avalanche count peak bn+1 / n+2 formed by the avalanche count peak bn+1 and the avalanche count peak bn+2. Subsequently, the ranging device can repeatedly execute the above steps S401-S402 until the avalanche count peaks corresponding to the bn+1 to b2nth encoded pulse signals are superimposed to obtain the first superimposed histogram.

[0061] It should be particularly noted that since the generation interval durations between any two adjacent avalanche count peaks are different, after repeatedly executing the above steps S401-S403 to superimpose n avalanche count peaks to obtain the first superimposed histogram and the second superimposed histogram, each superimposed histogram will only have one significantly enhanced superimposed avalanche count peak. Furthermore, the avalanche count peak generated by the encoded pulse signal returned by the object to be measured can be significantly enhanced, and the avalanche count peak corresponding to the interfering echo signal can be suppressed.

[0062] S103. Perform anti-interference processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal.

[0063] In one embodiment, performing anti-interference processing on the first superimposed histogram and the second superimposed histogram is to remove the avalanche count peaks generated by the interfering echo signals in the first superimposed histogram and the second superimposed histogram.

[0064] Specifically, referring to Figure 6 , Figure 6 is a schematic diagram of the application scenario of the target interference-free histogram in a ranging method provided by an embodiment of the present application. Among them, Figure 6 after the above anti-interference processing, there will only be one avalanche count peak with a significantly higher peak value. That is, the avalanche count peak generated by the encoded pulse signal returned by the object to be measured, and the superimposed avalanche count peak finally obtained after the above processing.

[0065] As an example, the ranging device can superimpose the first superimposed histogram and the second superimposed histogram to obtain a third superimposed histogram. At the same time, subtract the first superimposed histogram from the second superimposed histogram to obtain a subtracted histogram. Finally, based on the third superimposed histogram and the subtracted histogram, generate a target interference-free histogram.

[0066] Specifically, the calculation formula for obtaining the target interference-free histogram can be as follows:

[0067] H1 = His1 + His2 - |His1 - His2|.

[0068] Among them, H1 is the target interference-free histogram, His1 is the first superimposed histogram, and His2 is the second superimposed histogram. That is, the absolute value of the difference between the third superimposed histogram and the subtracted histogram is subtracted to generate the target interference-free histogram.

[0069] It should be noted that the method of superimposing and subtracting the first superimposed histogram and the second superimposed histogram is similar to the method of generating the first superimposed histogram and the second superimposed histogram above, and both are to superimpose and subtract the avalanche count peaks at the same moment in the two superimposed histograms.

[0070] Specifically, to enhance again the avalanche count peak generated by the encoded pulse signal returned by the object to be measured and suppress the avalanche count peak corresponding to the interfering echo signal. When performing the above addition or subtraction processing, the second superimposed histogram can also be shifted according to the interval duration between the superimposed avalanche count peak in the first superimposed histogram and the superimposed avalanche count peak in the second superimposed histogram, so that the two superimposed avalanche count peaks in the first superimposed histogram and the shifted second superimposed histogram are at the same time. Then, the first superimposed histogram and the shifted second superimposed histogram are superimposed to obtain the third superimposed histogram, and subtracted to obtain the subtracted histogram.

[0071] At this time, after the two superimposed avalanche count peaks are superimposed, the peak will be significantly enhanced in the third superimposed histogram, and after the two avalanche count peaks are subtracted, the peak will not be significantly enhanced in the subtracted histogram. That is, after the third superimposed histogram and the subtracted histogram are subtracted, the target interference-free histogram can retain the new avalanche count peak obtained by superimposing the two superimposed avalanche count peaks that are significantly enhanced.

[0072] It can be understood that since the subtracted histogram is the absolute value of the subtraction of the avalanche count peaks in the first superimposed histogram and the second superimposed histogram. Therefore, when the first superimposed histogram does not have an avalanche count peak or has a small peak at time t1, and the second superimposed histogram has an avalanche count peak and a high avalanche count peak at time t1, the subtracted histogram after subtraction will also have an avalanche count peak (an avalanche count peak corresponding to an interfering echo signal) at time t1. Exemplarily, referring to Figure 7 , Figure 7It is a schematic diagram of the application scenario of the first superimposed histogram and the second superimposed histogram in a ranging method provided by an embodiment of the present application. Taking the time t1 as 360 ns as an example, at 360 ns, the first superimposed histogram has a relatively small avalanche count peak at 360 ns, and the second superimposed histogram has a relatively high avalanche count peak at the 360 ns moment. At this time, in the subtracted histogram after subtraction, there will also be a subtracted avalanche count peak at the 360 ns moment. The reduction amplitude of the avalanche count peak is relatively low.

[0073] Moreover, when the first superimposed histogram has an avalanche count peak (for example, a superimposed avalanche count peak) at the time t2, and the second superimposed histogram also has an avalanche count peak (for example, a superimposed avalanche count peak) at the time t2, at this time, the avalanche count peak of the subtracted histogram at the time t2 will approach 0. Exemplarily, referring to Figure 7 , taking the time t2 as 300 ns as an example, at 300 ns, the first superimposed histogram has an avalanche count peak at 300 ns, and the second superimposed histogram has an avalanche count peak at the 300 ns moment. At this time, in the subtracted histogram after subtraction, the avalanche count peak at the 300 ns moment will be significantly reduced.

[0074] Based on this, since the third superimposed histogram is obtained by adding the avalanche count peaks in the first superimposed histogram and the second superimposed histogram, when the first superimposed histogram has an avalanche count peak at the time t1, and the second superimposed histogram does not have an avalanche count peak or has a relatively small avalanche count peak at the time t1, at this time, even if the two avalanche count peaks in the first superimposed histogram and the second superimposed histogram are superimposed, the avalanche count peak existing in the third histogram at the time t1 is still relatively small. That is, in the third superimposed histogram, there is still a relatively small avalanche count peak at the 360 ns moment, so that the avalanche count peak at the 360 ns moment cannot be significantly enhanced in the third superimposed histogram.

[0075] Moreover, when the first superimposed histogram has an avalanche count peak (for example, a superimposed avalanche count peak) at the time t2, and the second superimposed histogram also has an avalanche count peak (for example, a superimposed avalanche count peak) at the time t2, at this time, after the two relatively high avalanche count peaks are superimposed, the avalanche count peak existing in the third superimposed histogram at the time t2 will be significantly enhanced. That is, in the third superimposed histogram, there will be a superimposed avalanche count peak at the 300 ns moment, so that the peak will be significantly enhanced in the subtracted histogram. The avalanche count peak at the 300 ns moment will approach the superposition of the avalanche count peaks of the first superimposed histogram and the second superimposed histogram at the 300 ns moment.

[0076] Furthermore, when subtracting the subtracted histogram from the third superimposed histogram, there is an avalanche count peak corresponding to an interfering echo signal at time t1. Therefore, after subtraction, the avalanche count peak of the target interference-free histogram at time t1 will decrease (suppressing the avalanche count peak generated by the interfering echo signal). Specifically, referring to Figure 8 , Figure 8 is a schematic diagram of the application scenario of the target interference-free histogram in a ranging method provided by another embodiment of the present application. Among them, in the target interference-free histogram, the avalanche count peak at 360 ns is lower than the avalanche count peak of the second superimposed histogram at 360 ns. That is, in the above interference suppression process, the avalanche count peak generated by the interfering echo signal is suppressed.

[0077] In addition, since the avalanche count peak of the subtracted histogram at time t2 approaches 0. Therefore, the avalanche count peak of the target interference-free histogram at time t2 will finally be equal to the avalanche count peak of the third superimposed histogram at time t2 (that is, enhancing the avalanche count peak generated by the coded pulse signal returned by the object to be measured). Specifically, referring to Figure 8 , in the target interference-free histogram, the avalanche count peak at 300 ns will approach the superposition of the avalanche count peaks of the first superimposed histogram and the second superimposed histogram at 300 ns. That is, in the above interference suppression process, the avalanche count peak generated by the coded pulse signal returned by the object to be measured is enhanced.

[0078] It should be added that even if there may be an avalanche count peak generated by an interfering echo signal at the same time in the first superimposed histogram and the second superimposed histogram during the above interference suppression process. However, after the avalanche count peak generated by the coded pulse signal returned by the object to be measured is enhanced through the steps of S401-S403 first and then the above interference suppression process, the significance of its enhancement will be much higher than the significance of the enhancement of the avalanche count peak generated by the interfering echo signal.

[0079] S104. Determine the distance to the object to be measured according to the target interference-free histogram.

[0080] In one embodiment, after obtaining the target interference-free histogram, peak searching (the highest avalanche count peak), centroid solving, and Pile-up processing can be sequentially performed based on the target interference-free histogram to obtain the distance between the ranging device and the radar. It can be understood that the distance obtained according to a single target interference-free histogram represents the distance between the ranging device and the object to be measured at a preset azimuth in the corresponding detection space. In this way, the distances between the ranging device and the objects to be measured at different detection azimuths can be obtained according to the same ranging method, so as to obtain the depth information of different detection regions of the objects to be measured in the detection space. Through these depth information, three-dimensional point cloud imaging can be realized, and further three-dimensional information sensing of the objects to be measured can be realized.

[0081] In this embodiment, the ranging device can sequentially transmit coded pulse signals to the object to be measured according to the transmission interval duration between 2n coded pulse signals in the target pulse signal, and receive the original histograms with avalanche count peaks generated by each returned coded pulse signal. Among them, n needs to be greater than or equal to 2. Then, according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, the avalanche count peaks corresponding to the 1st to nth coded pulse signals are sequentially superimposed, and the avalanche count peaks corresponding to the (n + 1)th to 2nth coded pulse signals are superimposed to obtain a first superimposed histogram and a second superimposed histogram. Since the transmission interval duration between any two adjacent coded pulse signals among the modulated 2n coded pulse signals is different. Therefore, when superimposing two avalanche count peaks in the original histogram according to the corresponding transmission interval duration (that is, the generation order of the avalanche count peaks), each avalanche count peak formed by the optical signal returned by the object to be measured can be superimposed based on the corresponding transmission interval duration. That is, in the first superimposed histogram and the second superimposed histogram, the n avalanche count peaks corresponding to the object to be measured are enhanced. However, since the avalanche count peaks (interference peaks) formed by the optical signals returned by multiple other non-objects to be measured in the original histogram are not spaced at the specially set transmission interval duration. Therefore, the avalanche count peaks corresponding to non-objects to be measured cannot be wave-peak superimposed based on the above transmission interval duration. That is, in the first superimposed histogram and the second superimposed histogram, the avalanche count peaks corresponding to non-objects to be measured cannot be enhanced. Therefore, the interference caused by the avalanche count peaks of non-objects to be measured to the avalanche count peaks of the object to be measured can be reduced. Based on this, the ranging device can perform interference removal based on the first superimposed histogram and the second superimposed histogram corresponding to the enhanced avalanche count peaks to obtain a target interference-free histogram, and accurately determine the interval distance from the object to be measured according to the target interference-free histogram. And during the ranging process, encoding n coded pulse signals into a group of pulse signal beams for ranging can evenly distribute the peak power in an original pulse signal to 2n coded pulse signals. Furthermore, the requirement for the peak optical power of the light source and the power consumption are reduced. And since the transmission interval duration between any two adjacent coded pulse signals among the modulated 2n coded pulse signals is different, that is, the interference between avalanche count peaks can be avoided, so the transmission interval duration between two adjacent transmissions of coded pulse signals does not need to be set to a long interval duration. Furthermore, when the distance of the object to be measured that can be measured is far, the ranging time required can also be reduced. That is, under the condition of limited ranging time and peak light source power, a farther ranging performance can also be obtained.

[0082] It should be noted that the embodiments of S101 - S104 above are methods for ranging based on the target pulse signal emitted once. However, when performing the above processing only based on the target pulse signal emitted once, the final obtained target interference - free histogram may still have relatively many and relatively significant avalanche count peaks generated by interference echo signals.

[0083] Based on this, in order to be able to reduce as much as possible the avalanche count peaks generated by interference echo signals and improve the measurement accuracy of the measured distance. In this embodiment, two target pulse signals can be sent, and the above S101 - S103 processing is respectively performed on each target pulse signal to obtain two target interference - free histograms. That is, the target pulse signals are divided into a first pulse signal and a second pulse signal, and the target interference - free histograms are also divided into a first interference - free histogram corresponding to the first pulse signal and a second interference - free histogram corresponding to the second pulse signal.

[0084] At this time, the ranging device can perform interference removal processing on the first interference - free histogram and the second interference - free histogram again to obtain a third interference - free histogram. Then, the interval distance from the object to be measured is determined according to the third interference - free histogram.

[0085] Among them, the method of performing interference removal on the first interference - free histogram and the second interference - free histogram to obtain the third interference - free histogram is similar to the method of performing interference removal on the first superimposed histogram and the second superimposed histogram in step S103 above, and will not be described herein again. And the method of determining the interval distance according to the third interference - free histogram is similar to the method in step S104 above, and will not be described herein again.

[0086] In another embodiment, in order to further avoid interference between adjacent coded pulse signals in the target pulse signal, when modulating the coded pulse signal, the time - length difference of the emission interval time between any two adjacent coded pulse signals can be set to be greater than a preset multiple of the preset signal half - peak width.

[0087] In one embodiment, the preset multiple can be set according to the actual situation, and there is no limitation thereto. Exemplarily, the above - mentioned preset multiple can be 5 times. Among them, the signal half - peak width of the coded pulse signal can be set by the staff in advance. Furthermore, based on the set signal half - peak width, when the staff modulates the coded pulse signal, the time - length difference of the emission interval time between any two adjacent coded pulse signals can be set to be greater than 5 times the signal half - peak width.

[0088] Moreover, in order to enable the ranging device to have sufficient charge to transmit the next coded pulse signal after transmitting a coded second pulse signal. In this embodiment, the transmission interval duration between any two adjacent coded pulse signals can be set to be greater than a preset duration. Further, after the ranging device transmits a coded pulse signal, the ranging device can have sufficient time to fully charge the discharge capacitor in the ranging device for the next transmission of the coded pulse signal.

[0089] Among them, the preset duration can be set by the staff according to the actual situation, and there is no limitation on this. Exemplarily, the above preset duration can be 40 ns or 50 ns.

[0090] Please refer to Figure 9 , Figure 9 which is a schematic structural diagram of a ranging device provided by an embodiment of the present application. In this embodiment, each module included in the ranging device is used to execute Figures 1 to 4 the corresponding steps in the corresponding embodiment. Specifically, please refer to Figures 1 to 4 and Figures 1 to 4 the relevant descriptions in the corresponding embodiments. For the sake of convenience of description, only the parts related to this embodiment are shown. Refer to Figure 9 , the ranging device 900 may include: an execution module 910, a superimposing module 920, a generating module 930, and a ranging module 940, where:

[0091] The execution module 910 is configured to sequentially transmit 2n modulated coded pulse signals in the target pulse signal to the object to be measured, and sequentially receive each returned coded pulse signal to respectively generate an original histogram with an avalanche count peak; the transmission interval duration between each coded pulse signal is different; n is an integer greater than or equal to 2.

[0092] The superimposing module 920 is configured to sequentially superimpose the avalanche count peaks corresponding to every n coded pulse signals respectively according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, to obtain a first superimposed histogram and a second superimposed histogram; the first superimposed histogram is obtained by superimposing the avalanche count peaks from the 1st to the nth in the generation order; the second superimposed histogram is obtained by superimposing the avalanche count peaks from the (n + 1)th to the 2nth in the generation order.

[0093] The generating module 930 is configured to perform interference removal processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal.

[0094] The ranging module 940 is configured to determine the interval distance from the object to be measured according to the target interference-free histogram.

[0095] In one embodiment, the superimposing module 920 is further configured to:

[0096] According to the target interval duration corresponding to the first avalanche count peak and the adjacent second avalanche count peak, shift each avalanche count peak in the original histogram by the target interval duration to obtain a shifted histogram with shifted avalanche count peaks; the first avalanche count peak is the avalanche count peak to be currently superimposed; superimpose the avalanche count peaks at the same time in the original histogram and the shifted histogram to obtain an initial superimposed histogram; the initial superimposed histogram contains a superimposed avalanche count peak formed by superimposing the first avalanche count peak and the second avalanche count peak; use the initial superimposed histogram as the new original histogram, and use the superimposed avalanche count peak as the new first avalanche count peak, and repeat the steps of obtaining the shifted histogram and the initial superimposed histogram until the avalanche count peaks corresponding to every n coded pulse signals are respectively superimposed to obtain a first superimposed histogram and a second superimposed histogram.

[0097] In one embodiment, the generating module 930 is further configured to:

[0098] Superimpose the first superimposed histogram and the second superimposed histogram to obtain a third superimposed histogram; subtract the first superimposed histogram from the second superimposed histogram to obtain a subtracted histogram; generate a target interference-free histogram based on the third superimposed histogram and the subtracted histogram.

[0099] In one embodiment, the generating module 930 is further configured to:

[0100] Subtract the absolute value of the third superimposed histogram from the subtracted histogram to generate a target interference-free histogram.

[0101] In one embodiment, the target pulse signal is divided into a first pulse signal and a second pulse signal, and the target interference-free histogram is divided into a first interference-free histogram corresponding to the first pulse signal and a second interference-free histogram corresponding to the second pulse signal; the ranging module 940 is further configured to:

[0102] Perform interference removal processing on the first interference-free histogram and the second interference-free histogram to obtain a third interference-free histogram; determine the interval distance from the object to be measured according to the third interference-free histogram.

[0103] In one embodiment, the modulated n coded pulse signals satisfy the following rules:

[0104] The time difference of the transmission interval duration between any two adjacent coded pulse signals is greater than a preset multiple of the preset signal half-peak width.

[0105] In one embodiment, the modulated n coded pulse signals satisfy the following rules:

[0106] The transmission interval duration between any two adjacent coded pulse signals is greater than a preset duration.

[0107] It should be understood that Figure 9 in the schematic structural diagram of the ranging device shown, each module is used to execute Figures 1 to 4 the steps in the corresponding embodiments, and for Figures 1 to 4 the steps in the corresponding embodiments have been explained in detail in the above embodiments. For details, please refer to Figures 1 to 4 and Figures 1 to 4 the relevant descriptions in the corresponding embodiments, which will not be elaborated here.

[0108] Figure 10 FIG. is a schematic structural diagram of a ranging device provided by an embodiment of the present application. As Figure 10 shown, the ranging device 1000 in this embodiment includes: a processor 1010, a memory 1020, and a computer program 1030 stored in the memory 1020 and executable on the processor 1010, such as a program for the ranging method. When the processor 1010 executes the computer program 1030, the steps in each of the above-mentioned ranging method embodiments are implemented, such as Figure 1 S101 to S104 shown. Alternatively, when the processor 1010 executes the computer program 1030, the functions of each module in the above Figure 9 corresponding embodiments are implemented. For example, Figure 9 the functions of each module shown. For details, please refer to Figure 9 the relevant descriptions in the corresponding embodiments.

[0109] Exemplarily, the computer program 1030 can be divided into one or more modules. One or more modules are stored in the memory 1020 and executed by the processor 1010 to implement the ranging method provided by the embodiments of the present application. One or more modules can 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 1030 in the ranging device 1000. For example, the computer program 1030 can implement the ranging method provided by the embodiments of the present application.

[0110] The ranging device 1000 may include, but is not limited to, a processor 1010 and a memory 1020. Those skilled in the art can understand that Figure 10 merely examples of the ranging device 1000 do not constitute a limitation on the ranging device 1000. It may include more or fewer components than shown in the figure, or combine some components, or different components. For example, the ranging device may further include input / output devices, network access devices, buses, etc.

[0111] The so-called processor 1010 may be a central processing unit, or may also be other general-purpose processors, digital signal processors, application-specific integrated circuits, off-the-shelf programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0112] The memory 1020 may be an internal storage unit of the ranging device 1000, such as the hard disk or memory of the ranging device 1000. The memory 1020 may also be an external storage device of the ranging device 1000, such as a plug-in hard disk, smart memory card, flash memory card, etc. equipped on the ranging device 1000. Further, the memory 1020 may also include both the internal storage unit of the ranging device 1000 and the external storage device.

[0113] The embodiment of the present application provides a computer-readable storage medium, and the computer-readable storage medium stores a computer program, and the computer program is executed by the processor to perform the ranging method in each of the above embodiments.

[0114] The embodiment of the present application provides a computer program product. When the computer program product runs on the ranging device, the ranging device is enabled to perform the ranging method in each of the above embodiments.

[0115] The above 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 make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of each embodiment of the present application, and should all be included in the protection scope of the present application.

Claims

1. A ranging method, characterized in that, the ranging method includes: sequentially transmitting 2n encoded pulse signals modulated in a target pulse signal to an object to be measured, and sequentially receiving each of the returned encoded pulse signals to respectively generate an original histogram having an avalanche count peak; the transmission interval duration between each of the encoded pulse signals is different; n is an integer greater than or equal to 2; according to the generation order of each of the avalanche count peaks and the generation interval duration between two adjacent avalanche count peaks, sequentially superimposing the avalanche count peaks corresponding to every n encoded pulse signals respectively to obtain a first superimposed histogram and a second superimposed histogram; the first superimposed histogram is obtained by superimposing the avalanche count peaks from the 1st to the nth in the generation order; the second superimposed histogram is obtained by superimposing the avalanche count peaks from the (n + 1)th to the 2nth in the generation order; performing anti-interference processing on the first superimposed histogram and the second superimposed histogram to generate a target anti-interference histogram corresponding to the target pulse signal; determining the interval distance from the object to be measured according to the target anti-interference histogram; the step of sequentially superimposing the avalanche count peaks corresponding to every n encoded pulse signals respectively according to the generation order of each of the avalanche count peaks and the generation interval duration between two adjacent avalanche count peaks to obtain a first superimposed histogram and a second superimposed histogram includes: shifting each of the avalanche count peaks in the original histogram by the target interval duration according to the first avalanche count peak and the target interval duration corresponding to the adjacent second avalanche count peak to obtain a shifted histogram having the shifted avalanche count peaks; the first avalanche count peak is the avalanche count peak to be superimposed currently; superimposing the avalanche count peaks at the same time in the original histogram and the shifted histogram to obtain an initial superimposed histogram; the initial superimposed histogram includes a superimposed avalanche count peak formed by superimposing the first avalanche count peak and the second avalanche count peak; taking the initial superimposed histogram as the new original histogram, and taking the superimposed avalanche count peak as the new first avalanche count peak, and repeating the steps of obtaining the shifted histogram and the initial superimposed histogram until the avalanche count peaks corresponding to every n encoded pulse signals are respectively superimposed to obtain the first superimposed histogram and the second superimposed histogram; the step of performing anti-interference processing on the first superimposed histogram and the second superimposed histogram to generate a target anti-interference histogram corresponding to the target pulse signal includes: superimposing the first superimposed histogram and the second superimposed histogram to obtain a third superimposed histogram; subtracting the first superimposed histogram from the second superimposed histogram to obtain a subtracted histogram; generating the target anti-interference histogram based on the third superimposed histogram and the subtracted histogram; subtracting the absolute values of the third superimposed histogram and the subtracted histogram to generate the target anti-interference histogram.

2. The ranging method according to claim 1, wherein, the target pulse signal is divided into a first pulse signal and a second pulse signal, and the target interference-free histogram is divided into a first interference-free histogram corresponding to the first pulse signal and a second interference-free histogram corresponding to the second pulse signal; the determining the distance interval from the object to be measured according to the target interference-free histogram includes: performing interference removal processing on the first interference-free histogram and the second interference-free histogram to obtain a third interference-free histogram; determining the distance interval from the object to be measured according to the third interference-free histogram.

3. The ranging method according to any one of claims 1-2, wherein, the n modulated coded pulse signals satisfy the following rules: the time difference of the transmission interval duration between any two adjacent coded pulse signals is greater than a preset multiple of the preset signal half-peak width.

4. The ranging method according to any one of claims 1-2, wherein, the n modulated coded pulse signals satisfy the following rules: the transmission interval duration between any two adjacent coded pulse signals is greater than a preset duration.

5. A ranging device, wherein, the ranging device includes: an execution module, configured to sequentially transmit 2n modulated coded pulse signals in the target pulse signal to an object to be measured, and sequentially receive each of the returned coded pulse signals to generate a raw histogram having an avalanche count peak; the transmission interval duration between each coded pulse signal is different; n is an integer greater than or equal to 2; a superimposing module, configured to sequentially superimpose the avalanche count peaks corresponding to every n coded pulse signals according to the generation order of each avalanche count peak and the generation interval duration between two adjacent avalanche count peaks, to obtain a first superimposed histogram and a second superimposed histogram; the first superimposed histogram is obtained by superimposing the avalanche count peaks from the 1st to the nth in the generation order; the second superimposed histogram is obtained by superimposing the avalanche count peaks from the (n + 1)th to the 2nth in the generation order; a generating module, configured to perform interference removal processing on the first superimposed histogram and the second superimposed histogram to generate a target interference-free histogram corresponding to the target pulse signal; a ranging module, configured to determine the distance interval from the object to be measured according to the target interference-free histogram; the superimposing module is further configured to: shift each of the avalanche count peaks in the raw histogram by the target interval duration according to the target interval duration corresponding to the first avalanche count peak and the adjacent second avalanche count peak, to obtain a shifted histogram having the shifted avalanche count peaks; the first avalanche count peak is the avalanche count peak to be currently superimposed; superimpose the avalanche count peaks at the same time in the raw histogram and the shifted histogram, to obtain an initial superimposed histogram; the initial superimposed histogram includes a superimposed avalanche count peak formed by superimposing the first avalanche count peak and the second avalanche count peak; Take the initial superimposed histogram as the new original histogram, and take the superimposed avalanche count peak as the new first avalanche count peak, and repeat the steps of obtaining the shifted histogram and the initial superimposed histogram until the avalanche count peaks corresponding to every n encoding pulse signals are respectively superimposed to obtain the first superimposed histogram and the second superimposed histogram; The generating module is further configured to: Superimpose the first superimposed histogram and the second superimposed histogram to obtain a third superimposed histogram; Subtract the first superimposed histogram from the second superimposed histogram to obtain a subtracted histogram; Generate the target interference-free histogram based on the third superimposed histogram and the subtracted histogram; Subtract the absolute value of the third superimposed histogram from the subtracted histogram to generate the target interference-free histogram.

6. A ranging device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein, When the processor executes the computer program, the ranging method according to any one of claims 1 to 4 is implemented.

7. A computer-readable storage medium storing a computer program, wherein, When the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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