A pulse light modulated laser ranging method, system, device and storage medium

Abstract

The present application provides a laser ranging method, system, device and storage medium based on pulse light modulation. The method includes: sending a high-frequency pulse wave signal at a preset frequency, the high-frequency pulse wave signal is modulated by a preset to form a first modulation signal and transmitted to an obstacle; the first modulation signal returns after encountering an obstacle; collecting a mixed signal formed by the second modulation signal returned after encountering the obstacle and the third modulation signal that has not reached the obstacle; analyzing the mixed signal to determine the mixing frequency Δf of the mixed signal; determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation. This scheme adopts the coherent principle for ranging, and only specific light needs to be filtered and recorded, with strong anti-interference ability, and the use of pulse light emission can increase the pulse light power under the same equivalent average light power, thereby achieving longer distance measurement.

Description

Technical Field

[0001] The present application relates to a pulse light modulated laser ranging method, device and storage medium, belonging to the technical field of ranging by light waves. Background Art

[0002] Among the existing technical solutions, the technical solution of achieving the purpose of ranging by emitting laser signals by laser is already relatively common. The pulsed laser ranging system has the advantages of simple measurement principle and fast measurement speed and is widely used in the field of ranging.

[0003] However, in the existing technical solutions using laser ranging, the ranging effect is relatively good for obstacles that are relatively close; but for obstacles that are relatively far away, the laser energy received by the photodetector after the pulsed laser emitted by the laser transmitter is diffusely reflected by the obstacle is extremely weak, and the echo pulse signal is submerged in the noise and cannot be extracted, which will make it impossible to achieve measurement at longer distances.

[0004] In summary, the existing technical solutions lack a technical solution that can achieve long-distance measurement by emitting laser signals. Summary of the invention

[0005] The present application provides a laser ranging method, system, device and storage medium based on pulse light modulation to solve the technical problem that the existing technical solutions lack a technical solution that can achieve long-distance measurement by emitting laser signals.

[0006] In a first aspect, according to an embodiment of the present application, a laser ranging method based on pulse light modulation is provided, which is used to measure the distance between an obstacle and a laser emitted by a laser emitting device, and is characterized by comprising:

[0007] A high-frequency pulse wave signal is sent at a preset frequency, and the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal which is transmitted to an obstacle; the first modulated signal is returned after encountering the obstacle;

[0008] Collecting a mixed signal formed by the second modulated signal returned after encountering the obstacle and the third modulated signal that has not reached the obstacle;

[0009] Analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal;

[0010] The distance to the obstacle is determined according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation.

[0011] In one embodiment, the preset modulation is frequency modulation or amplitude modulation.

[0012] In one embodiment, if the preset modulation is frequency modulation, determining the distance to the obstacle according to the bandwidth B, period T, mixing frequency Δf and the type of preset modulation of the first modulation signal includes:

[0013] Based on the first mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf;

[0014] The first mathematical model is:

[0015] D = c*T*Δf / (4B) (1-1);

[0016] Wherein, D is the distance between the laser emitting device and the obstacle.

[0017] In one embodiment, if the preset modulation is amplitude modulation, determining the distance to the obstacle according to the bandwidth B, period T, mixing frequency Δf and the type of preset modulation of the first modulation signal includes:

[0018] Based on the second mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf;

[0019] The second mathematical model is:

[0020] D = c*T*Δf / (2B) (1-2);

[0021] Wherein, D is the distance between the laser emitting device and the obstacle.

[0022] In one embodiment, it further includes:

[0023] Using the third mathematical model to obtain the first mathematical model;

[0024] The third mathematical model is:

[0025]

[0026] In one embodiment, it further includes:

[0027] Using the fourth mathematical model to obtain the second mathematical model;

[0028] The fourth mathematical model is:

[0029]

[0030] In a second aspect, according to an embodiment of the present application, a laser ranging system based on pulse light modulation is provided, which is applied to measure the distance between an obstacle and a laser emitted by a laser emitting device, and includes:

[0031] A transmitting module, used for transmitting a high-frequency pulse wave signal at a preset frequency, wherein the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal which is transmitted to an obstacle; the first modulated signal is returned after encountering an obstacle;

[0032] A mixed signal acquisition module, used for acquiring a mixed signal formed when the second modulated signal returned after encountering the obstacle meets the third modulated signal that has not reached the obstacle;

[0033] An analysis module, used for analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal;

[0034] The distance calculation module is used to determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation.

[0035] In one embodiment, the preset modulation is frequency modulation or amplitude modulation.

[0036] In a third aspect, according to an embodiment of the present application, a laser ranging device based on pulse light modulation is provided, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program is loaded and executed by the processor to implement any of the above-mentioned laser ranging methods based on pulse light modulation.

[0037] In a fourth aspect, according to an embodiment of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, wherein the computer program, when executed by a processor, is used to implement any of the above-mentioned laser ranging methods based on pulse light modulation.

[0038] The beneficial effects of this application are:

[0039] In summary, the laser ranging method based on pulse light modulation provided in the embodiment of the present application is that for the high-frequency pulse signal emitted by the laser emitting device, after being modulated by a preset to form a first modulation signal, it is emitted to the obstacle, and then the mixed signal formed by the second modulation signal returned after encountering the obstacle and the third modulation signal that has not reached the obstacle is collected, and the mixed signal is analyzed to determine the mixing frequency Δf, and then the distance to the obstacle can be determined according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf. In this scheme, the mixing signal can be analyzed to determine the mixing frequency Δf of the mixing signal, and then the distance to the obstacle can be calculated. In this scheme, the coherence principle is used for ranging, and only specific light needs to be filtered and recorded, and the anti-interference ability is strong. In addition, the use of pulse light emission can increase the pulse light power under the same equivalent average light power, thereby achieving longer distance measurement.

[0040] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram showing the time difference between the transmitting signal and the receiving signal;

[0042] Figure 2 A flow chart of a laser ranging method based on pulse light modulation provided in an embodiment of the present application;

[0043] Figure 3 A flowchart of another laser ranging method based on pulse light modulation provided in an embodiment of the present application;

[0044] Figure 4 A schematic diagram of a first modulation signal formed after a frequency modulation signal is adopted in a laser ranging method based on pulse light modulation provided in an embodiment of the present application;

[0045] Figure 5 A flowchart of another laser ranging method based on pulse light modulation provided in an embodiment of the present application;

[0046] Figure 6 A schematic diagram of an amplitude modulation signal used in an embodiment of the present application;

[0047] Figure 7 A schematic diagram of a laser ranging system based on pulse light modulation provided in an embodiment of the present application;

[0048] Figure 8 A block diagram of a laser ranging device based on pulse light modulation provided in accordance with an embodiment of the present application. DETAILED DESCRIPTION

[0049] The following examples are used to illustrate the present application but are not used to limit the scope of the present application.

[0050] An embodiment of the present application provides a laser ranging method, the main idea of ​​which is to emit a laser signal through a laser emitting device, and then add a modulation signal to the laser signal emitted by the laser emitting device, the laser signal with the modulated signal added is emitted to the obstacle, and returns left and right after being reflected by the obstacle. The third modulated laser signal entering the mixing device can be continuous, so it will meet the third modulated signal after the subsequently emitted laser signal is modulated. The present application is to analyze the mixing signal after the second modulation signal meets the third modulation signal, determine the mixing frequency Δf, and then determine the distance between the laser emitting device and the obstacle based on the analyzed mixing frequency Δf.

[0051] See also Figure 1 As shown, after encountering an obstacle, the laser signal S1 after adding the modulation signal returns, and the time difference between the echo signal S2 and the first modulation signal S1 is Δt.

[0052] See also Figure 2 As shown, an embodiment of the present application provides a laser ranging method based on pulse light modulation, which is used to measure the distance between an obstacle and a laser emitted by a laser emitting device. The method includes:

[0053] Step S22, sending a high-frequency pulse wave signal at a preset frequency, wherein the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal and transmitted to the obstacle; the first modulated signal returns after encountering the obstacle;

[0054] In an embodiment of the present application, the laser emitting device emits a high-frequency pulse wave signal at a set frequency (preset frequency). After the laser pulse signal is emitted, it is first modulated, that is, a preset modulation signal is added to the original emitted laser signal, and then it is emitted to the obstacle after the first modulation signal is formed.

[0055] In the embodiment of the present application, the preset modulation signal may be a frequency modulation signal or an amplitude modulation signal, and in actual adjustment, it may be set according to actual needs.

[0056] Step S24, collecting a mixed signal formed by the second modulated signal returned after encountering the obstacle and the third modulated signal that has not reached the obstacle;

[0057] In an embodiment of the present application, the original laser signal emitted is returned after encountering an obstacle. Based on the laser emitting device continuously emitting laser signals, the second modulated signal that is returned after adding a modulation signal and shooting towards the obstacle meets the third modulated signal that has not yet reached the obstacle during signal transmission, forming a mixed signal.

[0058] Step S26, analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal;

[0059] In the embodiment of the present application, after the mixing signal is formed, the mixing signal is analyzed. For example, a mixer may be used to collect, filter and perform FFT processing on the mixing signal to extract the mixing frequency Δf of the mixing signal.

[0060] Step S28: determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the preset modulation type.

[0061] In the embodiment of the present application, after determining the mixing frequency Δf of the mixing signal, the distance to the obstacle can be determined according to the bandwidth B of the first modulation signal, the period T of the first modulation signal and the mixing frequency Δf. It is noted that in the present application, based on different modulation types, corresponding mathematical models are used to calculate the distance to the obstacle.

[0062] In one embodiment, the preset modulation is frequency modulation or amplitude modulation.

[0063] In one embodiment of the present application, see Figure 3 As shown, in step S28, determining the distance to the obstacle according to the bandwidth B, period T, mixing frequency Δf and preset modulation type of the first modulation signal includes:

[0064] Step S281: if the preset modulation is frequency modulation, then based on a first mathematical model, determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf and the type of the preset modulation;

[0065] The first mathematical model is:

[0066] D = c*T*Δf / (4B) (1-1);

[0067] Wherein, D is the distance between the laser emitting device and the obstacle.

[0068] In one embodiment of the present application, the method further includes:

[0069] Step S271, using the third mathematical model to obtain the first mathematical model;

[0070] The third mathematical model is:

[0071]

[0072] In the embodiment of the present application, the first modulation signal after frequency modulation may be a triangular wave or a sawtooth wave. The embodiment of the present application is described by taking a triangular wave as an example. Figure 4 As shown, the model for obtaining the bandwidth B of the first modulated signal is: B = f1-f0. Through the geometric shape in the figure, we can get the proportional equation Δt / Δf ​​= (T / 2) / B, thereby obtaining: Δt = Δf*T / 2 / B, and the expression of the distance D to the obstacle is D = c* Δt / 2. Therefore, combining Δt = Δf*T / 2 / B and D = cΔt / 2, we can obtain D = c*TΔ*f / (4B).

[0073] It should be noted that in the figure, the solid line part is the time period when the laser emitting device is turned on for emitting light, and the dotted line part is the time period when the laser emitting device is turned off for not emitting light. The overall process is modulated according to the triangular wave law; wherein c is the speed of light, Δt is the time difference between the moment when the light is emitted and the moment when the light is received, Δf is the difference between the receiving frequency and the transmitting frequency when the return light is received, T is the period, f1 and f0 are the maximum frequency and the minimum frequency respectively, B is the frequency modulation bandwidth, D is the distance between the radar and the obstacle, and the optical path c*Δt / is twice the distance D.

[0074] In one embodiment of the present application, see Figure 5 As shown, in step S28, the distance to the obstacle is determined according to the bandwidth B, period T, mixing frequency Δf and preset modulation type of the first modulation signal, including:

[0075] If the preset modulation is amplitude modulation, then based on the second mathematical model, according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf, the distance to the obstacle is determined;

[0076] The second mathematical model is:

[0077] D = c*T*Δf / (2B) (1-2);

[0078] Wherein, D is the distance between the laser emitting device and the obstacle.

[0079] In an embodiment of the present application, different mathematical models are used to calculate the distance to the obstacle according to the type of preset modulation. If the preset modulation type is frequency modulation, a first mathematical model D=cTΔf / (4B) is used to determine the distance to the obstacle based on the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixed frequency Δf; and when the preset modulation type is amplitude modulation, a second mathematical model D=cTΔf / (2B) is used to determine the distance to the obstacle based on the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixed frequency Δf.

[0080] It can be seen from the first mathematical model and the second mathematical model that, based on different modulation types, corresponding coefficients are assigned, and the distance to the obstacle is determined according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf.

[0081] In another embodiment of the present application, the method further includes:

[0082] Step S272, using the fourth mathematical model to obtain the second mathematical model;

[0083] The fourth mathematical model is:

[0084]

[0085] In the embodiment of the present application, the laser emitting device emits a high-frequency pulse wave, and modulates its amplitude with a signal (f0-f1) whose frequency changes according to a sawtooth wave. The modulated signal will act on the signal strength (amplitude), and the modulated signal strength (amplitude) can be expressed as:

[0086] φ(t)=2π(f0t+kt 2 / 2) (1-10)

[0087] Among them, k represents the frequency change rate of the sawtooth wave from f0 to f1;

[0088] In the embodiment of the present application, the added modulation signal is a sawtooth wave signal, see Figure 6 As shown in Figure 1, when the high-frequency pulse wave signal (laser signal) emitted by the laser emitting device is reflected by an obstacle, it will carry the distance information between the obstacle and the phase, introducing a phase change of Among them, Δt=2D / c, which represents the time delay between the emission time of the high-frequency pulse wave signal and the reception time of the reflected light; f(t)=f0+k*t, which represents the corresponding relationship between the sawtooth wave frequency and time; the echo signal reflected by the obstacle is coherent with the transmitted signal, and the signal can obtain the frequency Δf=kτ after fast Fourier transform; wherein k=(f1-f0) / T, the mixed frequency Δf changes linearly with the distance to the obstacle, and the distance measurement value to the obstacle is: D=c*τ / 2=c*Δf / 2k=c*Δf*T / 2(f1-f0) and the target distance information to the obstacle can be further calculated, D=c*Δf*T / 2B, wherein B is the bandwidth of the first modulation signal, and T is the period of the first modulation signal.

[0089] When the high-frequency pulse signal emitted by the laser emitting device is modulated by amplitude modulation, the frequency ft of the emitted high-frequency pulse signal changes according to the law of periodic triangular waves, and its frequency modulation bandwidth is B, and the change period is T. The frequency of the echo reflected from the obstacle has the same change law as the emission frequency, but lags behind in time by Δt=2*D / c. The frequency difference between the emission and reception frequencies is the frequency of the intermediate frequency signal output by the mixer. The method disclosed in the present application can be applied to a laser ranging system including a transmitting device, a receiving device, and a mixer. The transmitting device generates a frequency modulated wave, and the function of the mixer is to complete the difference frequency of the echo and the local oscillator signal. The signal processing module in the mixer collects, filters, performs FFT and other processing on the difference frequency signal, extracts the frequency of the signal, and thus calculates the distance of the target.

[0090] In summary, the laser ranging method based on pulse light modulation provided in the embodiment of the present application is that for the high-frequency pulse signal emitted by the laser emitting device, after being modulated by a preset to form a first modulation signal, it is emitted to the obstacle, and then the mixed signal formed by the second modulation signal returned after encountering the obstacle and the third modulation signal that has not reached the obstacle is collected, and the mixed signal is analyzed to determine the mixing frequency Δf, and then the distance to the obstacle can be determined according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf. In this scheme, the mixing signal can be analyzed to determine the mixing frequency Δf of the mixing signal, and then the distance to the obstacle can be calculated. In this scheme, the coherence principle is used for ranging, and only specific light needs to be filtered and recorded, and the anti-interference ability is strong. In addition, the use of pulse light emission can increase the pulse light power under the same equivalent average light power, thereby achieving measurement at a longer distance.

[0091] Figure 5 is a block diagram of a laser ranging system based on pulse light modulation provided by an embodiment of the present application. Figure 2 The laser ranging method based on pulse light modulation is shown. The system includes at least the following modules:

[0092] The transmitting module 51 is used to send a high-frequency pulse wave signal at a preset frequency. The high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal and is transmitted to an obstacle. The first modulated signal returns after encountering an obstacle.

[0093] A mixed signal acquisition module 52, used for acquiring a mixed signal formed when the second modulated signal returned after encountering the obstacle meets the third modulated signal that has not reached the obstacle;

[0094] An analysis module 53 is used to analyze the mixing signal to determine the mixing frequency Δf of the mixing signal;

[0095] The distance calculation module 54 is used to determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation.

[0096] In the embodiment of the present application, the preset modulation is frequency modulation or amplitude modulation.

[0097] In the embodiment of the present application, if the preset modulation is frequency modulation, the distance calculation module is specifically used to:

[0098] Based on the first mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf;

[0099] The first mathematical model is:

[0100] D = c*T*Δf / (4B) (1-1);

[0101] Wherein, D is the distance between the laser emitting device and the obstacle.

[0102] Furthermore, it also includes: a first mathematical model obtaining module, used to obtain the first mathematical model using the third mathematical model;

[0103] The third mathematical model is:

[0104]

[0105] In the embodiment of the present application, the distance calculation module is specifically used for:

[0106] Based on the second mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf;

[0107] The second mathematical model is:

[0108] D = c*T*Δf / (2B) (1-2);

[0109] Wherein, D is the distance between the laser emitting device and the obstacle.

[0110] In one embodiment of the present application, it also includes:

[0111] A second mathematical model obtaining module, used for obtaining the second mathematical model by using the fourth mathematical model;

[0112] The fourth mathematical model is:

[0113]

[0114] It should be noted that the laser ranging method based on pulse light modulation provided in the above embodiment and the laser ranging system embodiment based on pulse light modulation belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0115] Figure 6The block diagram of a laser ranging device based on pulse light modulation provided by an embodiment of the present application, the laser ranging device based on pulse light modulation described in this embodiment can be a computing device such as a desktop computer, a laptop computer, a PDA, and a cloud server, and the device can include, but is not limited to, a processor and a memory. The laser ranging device based on pulse light modulation described in this embodiment at least includes a processor and a memory, the memory stores a computer program, the computer program can be run on the processor, and when the processor executes the computer program, the steps in the above-mentioned laser ranging method embodiment based on pulse light modulation are implemented, for example Figure 2-Figure 4 The steps of the laser ranging method based on pulse light modulation shown in any figure. Alternatively, when the processor executes the computer program, the functions of each module in the above-mentioned laser ranging device embodiment based on pulse light modulation are realized.

[0116] Exemplarily, the computer program can be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules can be a series of computer program instruction segments that can complete specific functions, and the instruction segments are used to describe the execution process of the computer program in the laser ranging device based on pulse light modulation. For example, the computer program can be divided into a transmitting module, a mixing signal acquisition module, a parsing module, and a distance calculation module, and the specific functions of each module are as follows:

[0117] A transmitting module, used for transmitting a high-frequency pulse wave signal at a preset frequency, wherein the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal which is transmitted to an obstacle; the first modulated signal is returned after encountering an obstacle;

[0118] A mixed signal acquisition module, used for acquiring a mixed signal formed when the second modulated signal returned after encountering the obstacle meets the third modulated signal that has not reached the obstacle;

[0119] An analysis module, used for analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal;

[0120] The distance calculation module is used to determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation.

[0121] The processor may include one or more processing cores, such as a 4-core processor, a 6-core processor, etc. The processor may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning. The processor is the control center of the laser ranging system based on pulse light modulation, and uses various interfaces and lines to connect the various parts of the entire laser ranging system based on pulse light modulation.

[0122] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the laser ranging system based on pulse light modulation by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required for a function, etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a memory device, or other volatile solid-state storage devices.

[0123] Those skilled in the art will appreciate that the device described in this embodiment is merely an example of a laser ranging device based on pulse light modulation, and does not constitute a limitation on the laser ranging system based on pulse light modulation. In other implementations, more or fewer components may be included, or certain components may be combined, or different components may be included. For example, a laser ranging device based on pulse light modulation may also include input and output devices, network access devices, buses, etc. The processor, memory, and peripheral device interface may be connected via a bus or a signal line. Each peripheral device may be connected to the peripheral device interface via a bus, a signal line, or a circuit board. Schematically, the peripheral devices include, but are not limited to, a radio frequency circuit, a touch display, an audio circuit, and a power supply.

[0124] Of course, the laser ranging device based on pulse light modulation may also include fewer or more components, which is not limited in this embodiment.

[0125] Optionally, the present application also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it is used to implement the steps of the above-mentioned laser ranging method based on pulse light modulation.

[0126] Optionally, the present application also provides a computer product, which includes a computer-readable storage medium, in which a program is stored, and the program is loaded and executed by a processor to implement the steps of the above-mentioned rule-based pulse light modulation laser ranging method embodiment.

[0127] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0128] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A laser ranging method based on pulse light modulation, which is used to measure the distance to an obstacle by using a laser emitted by a laser emitting device, characterized in that: include: Sending a high-frequency pulse wave signal at a preset frequency, wherein the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal and transmitted to the obstacle; The first modulated signal returns after encountering an obstacle; Collecting a mixed signal formed by the second modulated signal returned after encountering the obstacle and the third modulated signal that has not reached the obstacle; Analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal; Determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation; The preset modulation is frequency modulation or amplitude modulation; If the preset modulation is frequency modulation, determining the distance to the obstacle according to the bandwidth B, the period T, the mixing frequency Δf and the type of the preset modulation of the first modulation signal includes: Based on the first mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf; The first mathematical model is: ； (1-1) Where D is the distance between the laser emitting device and the obstacle; c is the speed of light; The laser ranging method based on pulse light modulation also includes: using a third mathematical model to obtain the first mathematical model; the third mathematical model is: If the preset modulation is amplitude modulation, determining the distance to the obstacle according to the bandwidth B, the period T, the mixing frequency Δf and the type of the preset modulation of the first modulation signal includes: Based on the second mathematical model, determining the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, and the mixing frequency Δf; The second mathematical model is: ； (1-4) The laser distance measurement method based on pulse light modulation also includes: using a fourth mathematical model to obtain a second mathematical model; The fourth mathematical model is: Among them, c is the speed of light; f0 is the minimum frequency; k is the frequency change rate of the sawtooth wave from f0 to f1.

2. A laser ranging system based on pulse light modulation, characterized in that: The system is applied to measure the distance between an object and an obstacle by using a laser emitted by a laser emitting device, and the system applies the laser ranging method based on pulse light modulation as claimed in claim 1, and the system comprises: A transmitting module, used for transmitting a high-frequency pulse wave signal at a preset frequency, wherein the high-frequency pulse wave signal is modulated by a preset frequency to form a first modulated signal which is transmitted to an obstacle; the first modulated signal is returned after encountering an obstacle; A mixed signal acquisition module, used for acquiring a mixed signal formed when the second modulated signal returned after encountering the obstacle meets the third modulated signal that has not reached the obstacle; An analysis module, used for analyzing the mixing signal to determine the mixing frequency Δf of the mixing signal; The distance calculation module is used to determine the distance to the obstacle according to the bandwidth B of the first modulation signal, the period T of the first modulation signal, the mixing frequency Δf, and the type of preset modulation.

3. The system according to claim 2, characterized in that The preset modulation is frequency modulation or amplitude modulation.

4. A laser ranging device based on pulse light modulation, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, characterized in that: The computer program is loaded and executed by the processor to implement the laser ranging method based on pulse light modulation as claimed in claim 1.

5. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it is used to implement the laser ranging method based on pulse light modulation as claimed in claim 1.

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