Rapid positioning method and device for space non-cooperative target

Abstract

The invention provides a rapid positioning method and device for a spatial non-cooperative target, and the method comprises the steps: generating a Gaussian beam, and equally dividing the Gaussian beam into a plurality of sub-beams with the same central energy intensity; different modulation parameters are applied to the sub-beams for modulation, and multiple groups of signal beams are obtained; enabling the plurality of signal light beams to intersect in a plane where the space target is located to form a light spot superposition area; acquiring a plurality of groups of echo signals generated by diffuse reflection of superposed light spots formed by the space target on the plurality of signal light beams, and determining a light intensity value of the echo signal corresponding to each sub light beam; and based on the light intensity value of each sub-beam echo signal and a Gaussian beam energy distribution model, establishing a geometric mapping relation between the light intensity and the target position, and resolving the relative position of the space target in a two-dimensional coordinate system with the center of the light spot superposition region as an original point, the geometric mapping relationship is a corresponding relationship between the light intensity value and the distance from the space target to the center of the light spot of each sub-beam.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of optical positioning of space targets, and particularly relates to a fast positioning method and device for a non-cooperative space target. BACKGROUND

[0002] The optical positioning technology of space targets is widely used in the fields of laser communication, laser ranging, astronomical observation, etc.

[0003] In the process of optical positioning of targets, the pointing mechanism of the optical positioning system controls the region where the target is aimed at, the optical information of the target is captured by the system receiving mechanism, and the position data of the space target is obtained after analysis and processing. Based on the cooperative relationship between the space target and the optical positioning system, the space target can be divided into two categories: one is a cooperative target, which means that the space target actively provides its own position information, which is obtained by the positioning system; the other is a non-cooperative target, which means that the space target cannot actively provide effective positioning information for the positioning system, such as being unable to provide beacon information, and can only rely on the terminal itself to obtain positioning information. There are a large number of non-cooperative space targets with such characteristics in the field of positioning of various space targets, and this technology can be widely applied in these fields, and has important practical application value.

[0004] The current research on non-cooperative space targets is mainly based on the detection of echo signals of a single laser beam, and the position information of the target is obtained by the positioning system using camera imaging detection and image processing algorithms. There are three main types of current positioning algorithms: the first type is statistical analysis method, such as Key rate method and chi-square detection method, which uses the linear or nonlinear relationship between the statistical parameters of the echo signal and the error to estimate the error through simulation database or statistical test, and relies on batch data; the second type is optimal estimation method, such as maximum likelihood estimation and high-order moment matching, which is based on the probability distribution or high-order statistical characteristics of the echo signal, and realizes error estimation through maximum likelihood function or signal matching, which relies on the target reflection model and has high computational complexity; the third type is real-time optimization algorithm, such as stochastic parallel gradient descent (SPGD), which uses echo signal strength as an indicator, and adjusts the control parameters in real time through random disturbance and gradient descent to approach the maximum value of echo strength to eliminate errors.

[0005] However, the statistical analysis method relies on batch data and has poor real-time performance; the optimal estimation method has high computational complexity and requires an accurate model; and the real-time optimization algorithm is sensitive to channel noise, difficult to tune parameters, and prone to local optimum. It is urgent to provide a new positioning method to avoid the above problems. SUMMARY

[0006] Therefore, the present application provides a fast positioning method and device for a non-cooperative space target, aiming to improve positioning efficiency, reduce computational burden, and avoid the problem of falling into local optimum.

[0007] In a first aspect, the application provides a rapid positioning method for a spatial non-cooperative target, comprising: generating a Gaussian light beam and equally dividing the Gaussian light beam into a plurality of sub-beams with consistent central energy intensity; respectively applying different modulation parameters to the sub-beams for modulation to obtain a plurality of groups of signal light beams; causing the plurality of signal light beams to converge at a plane where the spatial target is located to form a light spot superposition region; obtaining a plurality of groups of echo signals generated by the spatial target through diffuse reflection of the superimposed light spots formed by the plurality of signal light beams, and determining the light intensity values of the echo signals corresponding to each sub-beam; based on the light intensity values of the echo signals of the sub-beams and a Gaussian light beam energy distribution model, establishing a geometric mapping relationship between the light intensity and the target position, and solving the relative position of the spatial target in a two-dimensional coordinate system with the center of the light spot superposition region as the origin, wherein the geometric mapping relationship is a corresponding relationship between the light intensity value and the distance from the spatial target to the center of the light spot of each sub-beam.

[0008] Optionally, the included angle between any two adjacent light beams in the plurality of signal light beams is equal.

[0009] Optionally, the light intensity of any signal light beam decreases from the center of the light spot corresponding to the signal light beam to the edge of the light spot corresponding to the signal light beam.

[0010] Optionally, the included angle between any two adjacent light beams in the plurality of signal light beams is calculated according to the following formula:

[0011] In the formula, D represents the diameter of the light spot of the signal light beam in the plane where the spatial target is located; D0 represents the initial diameter of the light spot of the signal light beam; h represents the distance from the initial position of the signal light beam to the plane where the spatial target is located; and θ represents the beam divergence angle of the signal light beam.

[0012] Optionally, the step of establishing the geometric mapping relationship between the light intensity and the target position based on the light intensity values of the echo signals of the sub-beams and the Gaussian light beam energy distribution model comprises: establishing a geometric mapping relationship between the light intensity values and the direction where the spatial target is located according to the light intensity values of the echo signals of the sub-beams; establishing a geometric mapping relationship between the light intensity values, the spatial target, and the relative position of the light spot superposition center according to the light intensity values of the echo signals of the sub-beams and the Gaussian light beam energy distribution model.

[0013] Optionally, the step of establishing a geometric mapping relationship between the light intensity values and the direction where the spatial target is located according to the light intensity values of the echo signals of the sub-beams comprises:​​​​ Calculate the weight of each sub-beam echo signal using the following formula:

[0014]

[0015] Where, express The weight of the beamlet; Indicates the The light intensity of the sub-beam echo signal; Indicates the total number of sub-beams; The direction of the space target is calculated based on the weight and the unit direction vector of the two-dimensional projection of the sub-beam on the plane where the space target is located. The formula is as follows:

[0016] Where, Indicates the relative angle of the space target; Indicates the The projection of the sub-beam on the plane where the space target is located is The angle between the axes.

[0017] Optionally, the step of establishing a geometric mapping relationship between the light intensity value, the distance between the spatial target and the center of the light spot superposition according to the light intensity value of the echo signal of each sub-beam and the Gaussian beam energy distribution model includes: Calculate the weight of each sub-beam echo signal using the following formula:

[0018]

[0019] Where, express The weight of the beamlet; Indicates the The intensity of the sub-beam echo signal; Indicates the total number of sub-beams; Beam sub-beam correspondence dimensional simplex, which Vertices can be constructed dimensional space coordinate frame, determine The two-dimensional coordinates of the projection of a vertex on the plane where the space target is located are calculated as follows:

[0020]

[0021] Where, Indicates the a horizontal coordinate of a two-dimensional coordinate of a vertex corresponding to the beam sub-beam on a projection on a plane where the space target is located; denotes a first a vertical coordinate of a two-dimensional coordinate of a vertex corresponding to the beam sub-beam on a projection on a plane where the space target is located; is a two-dimensional projection matrix; denotes a first a vertex corresponding to the beam sub-beam on a projection on a plane where the space target is located a first a coordinate in a three-dimensional coordinate frame; According to the weight of the echo signal corresponding to the sub-beam and the two-dimensional coordinate of the projection of each sub-beam on the plane where the space target is located, the relative coordinate of the space target on the two-dimensional plane is determined; the formula is as follows:

[0022]

[0023] In the formula, denotes the relative coordinate of the space target on the two-dimensional plane axis; denotes the relative coordinate of the space target on the two-dimensional plane axis.

[0024] In a second aspect, the application provides a rapid positioning device for a space non-cooperative target, comprising: A generating module is configured to generate a Gaussian beam and divide the Gaussian beam into multiple beam sub-beams with consistent central energy intensity. A modulating module is configured to modulate the sub-beams by applying different modulation parameters to obtain multiple groups of signal beams. An overlapping module is configured to make the multiple beam signal beams intersect on a plane where the space target is located to form a light spot overlapping area, and the center position of the light spot overlapping area is a positioning origin. An acquiring module is configured to acquire multiple groups of echo signals generated by diffuse reflection of the overlapping light spots formed by the multiple beam signal beams on the space target, and determine the light intensity value of the echo signal corresponding to each sub-beam. A coordinate solving module is configured to establish a geometric mapping relationship between the light intensity and the target position based on the light intensity value of the echo signal of each sub-beam and a Gaussian beam energy distribution model, and solve the relative position of the space target in a two-dimensional coordinate system with the center of the light spot overlapping area as the origin. The geometric mapping relationship is a corresponding relationship between the light intensity value and the distance from the space target to the center of the light spot of each sub-beam.

[0025] In a third aspect, the application provides a positioning device, comprising the rapid positioning device for a space non-cooperative target as described above.

[0026] In a fourth aspect, the present application provides a computer readable storage medium, which stores at least one program code, and the program code is executed by a processor to implement the method for quickly positioning a spatial non-cooperative target according to any one of the above aspects.

[0027] The technical scheme provided by the present application has at least the following beneficial effects: Firstly, the present application superimposes multiple groups of the same sub-beams to form a light spot superimposition area, and the superimposed light spot irradiates on the spatial target. By obtaining the light intensity values of the echo signals of the sub-beams, the relative position of the spatial target in the two-dimensional coordinate system is determined. After the relative position of the spatial target in the two-dimensional coordinate system of the target plane is determined, the spatial target can be laser pointed by a two-dimensional laser pointing device (here, the two-dimensional pointing device corresponds to the pointing subsystem in the first aspect) through the relative position, so as to realize the quick positioning of the spatial target. Figure 2

[0028] Secondly, by modulating the sub-beams into signal beams, it can be ensured that when the echo signals are demodulated after being received, the sub-beams corresponding to each echo signal can be distinguished (originally, multiple sub-beams are the same, and the sub-beams are modulated into signal beams by using different modulation information, and the correspondence between the sub-beams and the echo signals can be determined through the modulation information).

[0029] Thirdly, the present application focuses on the determination of the position of the spatial target, and only relies on the light intensity data of each beam at the current moment for calculation, thereby skipping the dependence on the linear or nonlinear relationship between the statistical parameters of the echo signals and the errors. This method significantly reduces the demand for batch data, improves the positioning efficiency and real-time performance. By directly using the light intensity measurement value, this method avoids the delay problem in the statistical analysis method, and also reduces the calculation burden caused by the need for an accurate model in the optimal estimation method. Since no complex probability distribution matching or high-order moment calculation is involved, this scheme is more simple and efficient in implementation, and can quickly respond to changes in the target position. Compared with the real-time optimization algorithm, the present application does not depend on random disturbance, and reduces the complexity of parameter tuning and the risk of falling into local optimum. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical scheme in the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

[0031] Figure 1 The flow chart of the method for quickly positioning a spatial non-cooperative target provided by an embodiment of the present application;​ Figure 2 A structural block diagram of a fast positioning device for a space non-cooperative target according to an embodiment of the present application; Figure 3 A flow chart of a positioning process implemented by a fast positioning device for a space non-cooperative target according to an embodiment of the present application; Figure 4 A schematic diagram of an installation optical axis angle of a collimator according to an embodiment of the present application; Figure 5 A schematic diagram of a relative position of a collimator according to an embodiment of the present application; Figure 6 A schematic diagram of an adjacent collimator included angle and related parameters according to an embodiment of the present application; Figure 7 A schematic diagram of a multi-beam superposition energy distribution according to an embodiment of the present application; Figure 8 A schematic diagram of a target relative position in a solving model according to an embodiment of the present application; Figure 9 A schematic diagram of a target absolute distance solving according to an embodiment of the present application; Figure 10 A schematic diagram of a signal superposition according to an embodiment of the present application; Figure 11 A schematic diagram of a system work flow according to an embodiment of the present application; Figure 12 A structural block diagram of a fast positioning device for a space non-cooperative target according to another embodiment of the present application; Figure 13 A structural block diagram of a positioning device according to an embodiment of the present application.

[0032] Reference signs are as follows: 1: a transmitting subsystem; 11: a multi-beam light source module; 111: a laser unit; 112: a light splitting unit; 113: a laser modulation unit; 1131: an intensity balancing unit; 1132: a spatial light modulation unit; 114: a feedback control unit; 12: a multi-beam diversity control module; 121: a light beam collimation unit; 122: an angle control unit; 2: a receiving subsystem; 21: a photoelectric receiving module; 211: an optical telescope unit; 212: a photoelectric detection unit; 22: a signal processing module; 221: a noise processing unit; 222: a feature analysis unit; 223: a position analysis unit; 3: a pointing subsystem; 31: a high-precision motor unit; 32: a control unit; 4: a fast positioning device for a space non-cooperative target; 41: a generating module; 42: a modulating module; 43: a superposition module; 44: an acquiring module; 45: a position solving module; 5: positioning device; 51: processor; 52: memory. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0034] Figure 1 A flow chart of a fast positioning method of a spatial non-cooperative target according to an embodiment of the present application is provided. Referring to Figure 1 , the method comprises the following steps. S101, generating a Gaussian light beam and equally dividing the Gaussian light beam into multiple sub-beams with consistent central energy intensity.

[0035] S102, respectively applying different modulation parameters to the sub-beams to modulate the sub-beams to obtain multiple groups of signal light beams.

[0036] S103, making the multiple groups of signal light beams intersect at a plane where the spatial target is located to form a light spot superposition area.

[0037] In an example, the included angle between any two adjacent light beams in the multiple groups of signal light beams is equal.

[0038] In an example, the light intensity of any one signal light beam decreases from the center of the light spot corresponding to the signal light beam to the edge of the light spot corresponding to the signal light beam.

[0039] It should be noted that when the included angle between any two adjacent light beams is equal and the light intensity of any one signal light beam decreases from the center to the edge, the intensity of the echo signal reflected by the multiple light beams can be used to determine the two-dimensional coordinates of the spatial target. The principle used is that the position of the spatial target is fixed, after the multiple light beams intersect to form a light spot superposition area, the light spot superposition area irradiates on the spatial target, and each light beam will generate an echo signal. Since the light intensity of each signal light beam decreases along the radial direction, according to the intensity of the echo signal, the distance of the spatial target from the center of the signal light beam can be determined, and the coordinates of the spatial target on the two-dimensional plane where the spatial target is located can be determined through the distance between the spatial target and the center of the multiple signal light beams (because the coordinates of the center of each signal light beam are relatively determined). Even if the target is not in the multiple light spot superposition area, the approximate direction of the target can also be determined according to the type of the echo signal.

[0040] In an example, the included angle between any two adjacent light beams in the multiple groups of signal light beams is calculated according to the following formula:

[0041] In the formula, represents the diameter of the spot of the signal beam in the plane where the spatial target is located; represents the initial diameter of the spot of the signal beam; represents the distance between the initial position of the signal beam and the plane where the spatial target is located; represents the size of the beam divergence angle of the signal beam.

[0042] S104, obtaining a plurality of groups of echo signals generated by the diffuse reflection of the superimposed spot formed by the plurality of signal beams on the spatial target, and determining the light intensity value of the echo signal corresponding to each sub-beam.

[0043] S105, based on the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model, establishing a geometric mapping relationship between the light intensity and the target position, and solving the relative position of the spatial target in a two-dimensional coordinate system with the center of the spot superposition area as the origin, the geometric mapping relationship is the corresponding relationship between the light intensity value and the distance from the spatial target to the center of each sub-beam spot.

[0044] In an example, step S105 includes: Step 1, according to the light intensity value of each sub-beam echo signal, a geometric mapping relationship between the light intensity value and the direction where the spatial target is located is established.

[0045] In an example, step 1 includes: First, calculate the weight of each sub-beam echo signal, and the calculation formula is as follows:

[0046]

[0047] In the formula, represents the weight of the sub-beam; the first represents the first light intensity of the sub-beam echo signal; represents the total number of sub-beams; Second, according to the weight and the unit directional vector of the two-dimensional projection of the sub-beam in the plane where the spatial target is located, the direction where the spatial target is located is calculated, and the formula is as follows:

[0048] In the formula, represents the relative angle of the spatial target; represents the first the included angle between the projection of the sub-beam in the plane where the spatial target is located and the axis.

[0049] Step 2: Based on the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model, a geometric mapping relationship between the light intensity value, the relative position of the spatial target and the center of the light spot superposition is established.

[0050] In one example, step 2 includes: The first step is to calculate the weight of each sub-beam echo signal. The calculation formula is as follows:

[0051]

[0052] Where, express The weight of the beamlet; Indicates the The light intensity of the sub-beam echo signal; Indicates the total number of sub-beams; Step 2 Beam sub-beam correspondence dimensional simplex, which Vertices can be constructed dimensional space coordinate frame, determine The two-dimensional coordinates of the projection of a vertex on the plane where the space target is located are calculated as follows:

[0053]

[0054] Where, Indicates the The abscissa of the two-dimensional coordinates of the projection of the vertex corresponding to the sub-beam on the plane where the space target is located; Indicates the The ordinate of the two-dimensional coordinate of the projection of the vertex corresponding to the sub-beam on the plane where the space target is located; is a two-dimensional projection matrix; Indicates the The vertex corresponding to the sub-beam is The first dimension in the coordinate frame of space dimensional coordinates; Step 3: Determine the relative coordinates of the space target on the two-dimensional plane based on the weights of the echo signals corresponding to the sub-beams and the two-dimensional coordinates of the projections of each sub-beam on the plane where the space target is located. The formula is as follows:

[0055]

[0056] Where, representing the relative coordinates of the spatial target in a two-dimensional plane on the axis; representing the relative coordinates of the spatial target in a two-dimensional plane on the axis.

[0057] Figure 2 A structural block diagram of a fast positioning device for a spatial non-cooperative target according to another embodiment of the present application is provided. Referring to Figure 2 , the device comprises: a transmitting subsystem 1 for transmitting a laser beam to irradiate the spatial target and generate a return signal through diffuse reflection. The transmitting subsystem comprises: a multi-beam light source module 11, which is an optical system for generating multiple Gaussian beams with the same wavelength and the same intensity of each beam through light splitting and control technology. The core of the module is composed of a laser unit 111, a light splitting unit 112, a laser modulation unit 113 (including an intensity balancing unit 1131 and a spatial light modulation unit 1132), and a feedback control unit 114. A single-mode laser (such as a fiber laser) provides an initial stable Gaussian beam, which is split into multiple beams by a fiber light splitting component to ensure the consistency of the central intensity of each Gaussian beam. The laser modulation unit provides modulation functions to ensure that different beam signals can be distinguished in the receiving subsystem. The feedback control unit is responsible for temperature control and closed-loop algorithm to ensure the long-term stability of the module operation; a multi-beam diversity control module 12, which controls the precise spatial arrangement and divergence angle of the collimator array to make the multiple Gaussian beams form a superimposed spot in the target area. The core of the module is composed of a beam collimation unit 121 and an angle control unit 122. Specifically, the collimators are fixed according to a predetermined geometric configuration, and the propagation direction of each beam is precisely controlled by fine-tuning the adjacent spacing and installation inclination to ensure that they converge on the far-field target plane. At the same time, a uniform specification of collimating lenses and beam expansion systems is adopted to strictly match the divergence angles of each beam, so that the beam spot size and energy distribution are consistent, and the light intensity distortion in the superposition area caused by divergence differences is avoided. The module can also integrate a precision electrically controlled displacement table to fine-tune the beam pointing in real time and dynamically adapt to changes in target position. Finally, a high-precision and high-stability superimposed light field is realized; a receiving subsystem 2 for receiving the return signal diffusely reflected by the spatial target and analyzing the signal characteristics to realize the positioning of the target. The subsystem comprises: a photoelectric receiving module 21, which is mainly composed of an optical telescope unit 211 and a photoelectric detection unit 212. The optical telescope unit uses a large-aperture telescope and a narrow-band filter to suppress background light, and combines with the photoelectric detector and the automatic gain control module in the photoelectric detection unit to realize wide dynamic range signal reception; A signal processing module 22, mainly composed of a noise processing unit 221, a feature analysis unit 222 and a position analysis unit 223. The noise processing unit 221 performs noise reduction processing on the received signal, and needs to ensure that the amplification multiples of the signals remain consistent during processing; the feature analysis unit 222 analyzes the features of the signal through an algorithm, such as extracting the signal light intensity information through a cross-correlation algorithm combined with filtering technology; the position analysis module 223 calculates the position of the target in real time according to the feature information. The feature analysis unit is used to collect and calculate the coordinates of the spatial target in the two-dimensional coordinate system with the center of the light spot superposition as the origin; A pointing subsystem 3, mainly composed of a high-precision motor unit 31 and a control unit 32. The pointing subsystem 3 realizes the light beam pointing function through a two-dimensional high-precision turntable and other actuators.

[0058] Figure 3 The flowchart of the positioning process of the fast positioning device of the space non-cooperative target provided by an embodiment of the application.

[0059] In combination Figure 1 , Figure 2 , Figure 3 , the application provides some specific embodiments taking three sub-beams as an example: First, laser modulation. Taking different signal carrier frequencies as an example, the frequency modulation of the laser beam can be performed by the master control module combined with the laser modulation unit. Different carrier frequencies are used for each light beam, such as , , , to ensure that each light beam signal can be distinguished by signal feature extraction in the receiving subsystem; Second, laser collimation. In this module, the collimator needs to be installed at a specific angle, and there are certain requirements for the divergence angle of the laser emitted by the collimator. As shown in Figure 4 , there is an included angle between the main optical axis of the subsystem and the beam splitting optical axis, which is determined according to the distance of the target and the beam divergence angle of the laser beam and the index of the initial diameter of the light beam. Taking three light beams as an example, the installation schematic diagram is shown in Figure 5 , the planes where the collimators are located need to be perpendicular to the installation plane, and a certain included angle needs to be maintained between the adjacent two collimators, i.e. , if it is three light beams, the collimators should be arranged in an equilateral triangle.

[0060] If the beam divergence angle of the laser beam is , the initial diameter of the laser beam is , the spot diameter of the light beam at the target plane is , the distance between the spot centers of the two light beams at the target plane is , and the distance from the active emission system to the target is Here we take two beams as an example to describe the relationship between adjacent collimators, as shown in Figure 6 , then:

[0061] If the detection distance is far, then can be ignored, and if the beam divergence angles of the laser beams are the same, then:

[0062] Third, feature analysis. In this module, it is necessary to ensure that the amplitude of the received signal is not changed, and the received signals of each beam can be separated and extracted by fast Fourier transform, correlation, etc. algorithm, especially the intensity value of each beam signal.

[0063] Because the channels of the three laser signals are almost the same, the laser energy fluctuations caused by the channels have almost the same effect on the intensity of each beam.

[0064] Fourth, position analysis. Position analysis is divided into direction analysis and distance analysis. For direction analysis, we use a geometric solving method based on multi-beam energy distribution: after the detector receives the echo signal, the light intensity of each beam is separated and solved , , : Taking three beams as an example, the control spot superposition part does not exceed the spot center, that is, the echo light intensity of a single beam in the superposition part decreases from the center of the spot, as shown in Figure 7 . The intensity of three beams A, B, and C is , , respectively. The relative coordinate point is . The relative position of the target system is solved by the formula: The , , are normalized to obtain , , :

[0065]

[0066]

[0067] As shown in Figure 8 , a two-dimensional coordinate system is established with the center of the equilateral triangle as the origin, and the relative position of the target is :

[0068]

[0069] Therefore, according to the signal strength , we convert it to the polar angle relative to the origin , i.e. the relative coordinate position of the target system and the direction relative to the superimposed center, then we have:

[0070] i.e.

[0071] After the quadrant correction (adjust the angle according to the sign of , ), we can obtain the specific angle information.

[0072] Each point inside the triangle can be represented by the weighted average of its vertices. By choosing different equilateral triangles, it is equivalent to translating, rotating or scaling the entire system, and these transformations will not change the relative position of P inside the triangle.

[0073] Similarly, in the case of n beams, we can obtain the relative coordinates and directions of the target system by calculating the weighted average of the data and projecting it onto the two-dimensional coordinate system through the simplest convex body (simplex) defined by n vertices in n-1 dimensional space.

[0074] For distance analysis, after we calculate the relative position and direction of the target from the light intensity of each echo beam, we need to determine the absolute distance between the target and the spot center.

[0075] If the total power is and the beam waist radius is , then:

[0076] i.e.

[0077] where, when the spot center intensity , i.e. , we have:

[0078] In the feature analysis unit, we successfully analyzed the light intensity of each beam. If the distance between the target position and the spot center of one beam is , and the calculated light intensity of this beam is , then we have:

[0079] Taking the natural logarithm, we get:

[0080] If the light intensity information obtained via the feature analysis unit is (x = 1, 2, 3), the distance from the target to the center of each light beam spot is (x = 1, 2, 3), then:

[0081]

[0082]

[0083] If the distance from each echo light beam to the center of its spot is respectively , , , as shown in Figure 9 , if the distance from the target position to the center of the superposition is , is the distance between the center of each two light beam spots on the plane of the spatial target, then:

[0084] That is:

[0085] After calculating and , the spatial coordinates of the vacant target can be determined.

[0086] Figure 10 It is a schematic diagram of the light beam propagation process provided by an embodiment of the present application.

[0087] Figure 11 It is a flowchart of positioning a spatial target provided by another embodiment of the present application.

[0088] The present application provides a fast positioning method and device for a spatial non-cooperative target, which quickly calculates the relative position of the spatial target by using a geometric calculation method based on the energy distribution of multiple light beams. The method of modulating light beams in the transmitting subsystem and demodulating light beams in the receiving subsystem reduces channel interference. The main innovative content is as follows: 1. The present application focuses on the determination of the position of the spatial target, and only relies on the light intensity data of each light beam at the current moment for calculation, skipping the dependence on the linear or nonlinear relationship between the statistical parameters of the echo signal and the error. This method significantly reduces the demand for batch data, improves the positioning efficiency and real-time performance; 2. By directly using the light intensity measurement, this method avoids the delay problem in statistical analysis method, and also reduces the calculation burden caused by the need for accurate model in optimal estimation method; 3. Since it does not involve complex probability distribution matching or high-order moment calculation, this scheme is more simple and efficient in implementation, and can quickly respond to changes in target position. At the same time, compared with real-time optimization algorithm, this scheme does not depend on random disturbance, and reduces the complexity of parameter tuning and the risk of falling into local optimum.

[0089] Figure 12 A structural block diagram of a fast positioning device for a space non-cooperative target is provided for an embodiment of the present application. Referring to Figure 12 , the fast positioning device for a space non-cooperative target 4 comprises: A generating module 41 for generating a Gaussian light beam and equally dividing the Gaussian light beam into a plurality of sub-beams with consistent central energy intensity; A modulating module 42 for modulating the sub-beams by applying different modulation parameters to the sub-beams respectively to obtain a plurality of groups of signal light beams; An overlapping module 43 for causing the plurality of signal light beams to converge at a plane where the space target is located to form a light spot overlapping area, and the center position of the light spot overlapping area is a positioning origin; An acquiring module 44 for acquiring a plurality of groups of echo signals generated by diffuse reflection of the overlapping light spots formed by the plurality of signal light beams by the space target, and determining the light intensity values of the echo signals corresponding to each sub-beam; A position solving module 45 for establishing a geometric mapping relationship between the light intensity and the target position based on the light intensity values of the echo signals of the sub-beams and a Gaussian light beam energy distribution model, and solving the relative position of the space target in a two-dimensional coordinate system with the center of the light spot overlapping area as the origin, wherein the geometric mapping relationship is a corresponding relationship between the light intensity value and the distance from the space target to the center of the light spot of each sub-beam.

[0090] It should be noted that, Figure 12 The device in Figure 2 can be divided into more modules according to functions, which are not limited herein.

[0091] Figure 13 A structural block diagram of a positioning device is provided for an embodiment of the present application. Referring to Figure 13 , the positioning device 5 can comprise Figure 12 The fast positioning device for a space non-cooperative target 4 described above. Generally, the positioning device 5 comprises a processor 51 and a memory 52.

[0092] The processor 51 may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor 51 may be implemented in hardware using at least one of the following: a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), or a PLA (Programmable Logic Array). The processor 51 may also include a main processor and a coprocessor. The main processor is used to process data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor used to process data in the standby state. The memory 52 may include one or more computer-readable storage media, which may be non-transitory. The memory 52 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 52 is used to store at least one instruction, which is executed by the processor 51 to implement the method for rapidly locating non-cooperative targets in space performed by an electronic device, as provided in the method embodiments of the present application.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for rapidly locating non-cooperative targets in space, characterized in that: include: Generate a Gaussian beam and divide the Gaussian beam into multiple sub-beams with the same central energy intensity; Applying different modulation parameters to the sub-beams respectively to modulate them, thereby obtaining multiple groups of signal beams; Make multiple signal beams intersect at the plane where the space target is located to form a spot superposition area; Acquire multiple groups of echo signals generated by diffuse reflection of the superimposed light spots formed by multiple signal beams by the space target, and determine the light intensity value of the echo signal corresponding to each sub-beam; Based on the light intensity value of the echo signal of each sub-beam and the Gaussian beam energy distribution model, a geometric mapping relationship between light intensity and target position is established, and the relative position of the spatial target in the two-dimensional coordinate system with the center of the light spot superposition area as the origin is calculated. The geometric mapping relationship is the correspondence between the light intensity value and the distance from the spatial target to the center of each sub-beam light spot.

2. The method for rapidly locating a non-cooperative target in space according to claim 1, characterized in that: The included angles between any two adjacent light beams in the multiple signal light beams are equal.

3. The method for rapidly locating a non-cooperative target in space according to claim 1, wherein: The light intensity of any signal light beam decreases from the center of the light spot corresponding to the signal light beam to the edge of the light spot corresponding to the signal light beam.

4. The method for rapidly locating a non-cooperative target in space according to claim 1, wherein: The calculation formula for the angle between any two adjacent beams in multiple signal beams is as follows: Where, Indicates the diameter of the signal beam spot on the plane where the space target is located; Indicates the initial diameter of the signal beam spot; Indicates the distance between the initial position of the signal beam and the plane where the space target is located; Indicates the beam divergence angle of the signal beam.

5. The method for rapidly locating a non-cooperative target in space according to any one of claims 1 to 4, characterized in that: The steps of establishing a geometric mapping relationship between light intensity and target position based on the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model include: According to the light intensity value of each sub-beam echo signal, a geometric mapping relationship between the light intensity value and the direction of the space target is established; According to the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model, a geometric mapping relationship between the light intensity value, the spatial target and the relative position of the spot superposition center is established.

6. The method for rapidly locating a non-cooperative target in space according to claim 5, characterized in that: The steps of establishing a geometric mapping relationship between the light intensity value and the direction of the space target according to the light intensity value of the echo signal of each sub-beam include: Calculate the weight of each sub-beam echo signal using the following formula: Where, express The weight of the beamlet; Indicates the The intensity of the sub-beam echo signal; Indicates the total number of sub-beams; The direction of the space target is calculated based on the weight and the unit direction vector of the two-dimensional projection of the sub-beam on the plane where the space target is located. The formula is as follows: Where, Indicates the relative angle of the space target; Indicates the The projection of the sub-beam on the plane where the space target is located is The angle between the axes.

7. The method for rapidly locating a non-cooperative target in space according to claim 5, characterized in that: The steps of establishing a geometric mapping relationship between the light intensity value, the distance between the spatial target and the center of the light spot superposition according to the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model include: Calculate the weight of each sub-beam echo signal using the following formula: Where, express The weight of the beamlet; Indicates the The intensity of the sub-beam echo signal; Indicates the total number of sub-beams; Beam sub-beam correspondence dimensional simplex, which Vertices can be constructed dimensional space coordinate frame, determine The two-dimensional coordinates of the projection of a vertex on the plane where the space target is located are calculated as follows: Where, Indicates the The abscissa of the two-dimensional coordinates of the projection of the vertex corresponding to the sub-beam on the plane where the space target is located; Indicates the The ordinate of the two-dimensional coordinate of the projection of the vertex corresponding to the sub-beam on the plane where the space target is located; is a two-dimensional projection matrix; Indicates the The vertex corresponding to the sub-beam is The first dimension in the coordinate frame of space dimensional coordinates; The relative coordinates of the space target on the two-dimensional plane are determined based on the weights of the echo signals corresponding to the sub-beams and the two-dimensional coordinates of the projections of each sub-beam on the plane where the space target is located. The formula is as follows: Where, Represents the space target on a two-dimensional plane Relative coordinates of the axes; Represents the space target on a two-dimensional plane Relative coordinates of the axes.

8. A rapid positioning device for non-cooperative targets in space, characterized in that: include: A generation module, used for generating a Gaussian beam and evenly dividing the Gaussian beam into multiple sub-beams with uniform central energy intensities; A modulation module is used to apply different modulation parameters to each sub-beam to obtain multiple groups of signal beams; A superposition module is used to make multiple signal light beams intersect at the plane where the space target is located to form a spot superposition area, and the center position of the spot superposition area is the positioning origin; An acquisition module is used to acquire multiple groups of echo signals generated by diffuse reflection of the superimposed light spots formed by multiple signal beams by the space target, and to determine the light intensity value of the echo signal corresponding to each sub-beam; The position solving module is used to establish a geometric mapping relationship between light intensity and target position based on the light intensity value of each sub-beam echo signal and the Gaussian beam energy distribution model, and solve the relative position of the spatial target in the two-dimensional coordinate system with the center of the light spot superposition area as the origin. The geometric mapping relationship is the correspondence between the light intensity value and the distance from the spatial target to the center of each sub-beam light spot.

9. A positioning device, characterized in that: The device comprises the rapid positioning device for non-cooperative space targets as claimed in claim 8.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores at least one program code, and the program code is executed by a processor to implement the method for rapidly positioning a non-cooperative target in space as claimed in any one of claims 1 to 7.

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