System and method for selecting site of optical measurement equipment for space target measurement based on optimal observed energy efficiency

Abstract

Method for selecting site of optical measurement equipment for space target measurement based on optimal observation energy efficiency, which relates to the field of optimizing the layout of optoelectronic observation equipment, solves the problems that the existing site selection methods only target the observation of fixed ballistic targets, and when the ballistic of the target to be observed changes, the optimal site needs to be recalculated, etc. The selection system includes a preset information input unit, a target orbit simulation unit, an observability evaluation unit, a rendezvous simulation unit, an observation efficiency evaluation unit and a site recommendation unit; The method of the present invention constructs an optimization function to be optimized based on the observation duration, the rendezvous duration and the comprehensive scoring of the rendezvous, and uses the particle swarm optimization algorithm to perform iterative optimization within the given site selection range, and finally gives a set of optimal solutions for site selection, providing guiding significance for the final selection of the site.

Description

Technical Field

[0001] The present invention relates to the field of optimization of the layout of optoelectronic observation equipment, and particularly relates to a method for selecting a site for an optical measurement device for space target measurement based on optimal observation energy efficiency. Background Art

[0002] With the development of space technologies in various countries, various types of space targets have been launched into space. To ensure national security and monitor the status of its own satellites in real time, the space target surveillance system plays a fundamental and crucial role. Space targets mainly refer to satellites, including working satellites and non-working satellites, and also include various space debris, such as booster rockets, protective covers, and other objects entering space orbits, and also include various space vehicles entering the outer space of the Earth, such as comets and asteroids. The surveillance of space targets is of great significance. It can not only help determine the space capabilities of potential enemies, but also predict the orbits of space objects, and give warnings about possible collisions and attacks on its own space systems. Ground-based optoelectronic detection equipment is an important component of it. It has high measurement accuracy. A single optoelectronic detection equipment can only measure the angular information of the target and cannot obtain the distance information of the target. By performing intersection measurement with two or more optical measurement devices, the three-dimensional position of the target can be obtained to complete the determination of the orbital parameters of the space target. The selection of the sites of multiple optoelectronic detection devices is related to the use efficiency of the entire system. The existing site selection method is to qualitatively give the optimal site from multiple alternative sites considering various influences. Currently, a method for quantitatively measuring the pros and cons of site selection is needed.

[0003] Ground-based optoelectronic detection equipment is an important component of the space target surveillance system. It can provide the angular information of the space target relative to the measurement station and has high measurement accuracy. Intersection measurement with multiple optical measurement devices can obtain the three-dimensional position of the target and provide data for cataloging space targets. The selection of the sites of multiple devices has a greater impact on the final working efficiency of the system. However, there are few existing site selection methods for optoelectronic equipment. Most of them rely on the experience of business personnel to qualitatively select from multiple alternative sites.

[0004] The existing site optimization methods for optoelectronic observation equipment are all aimed at observing targets of range missiles. Due to the characteristics of range measurement, before each mission, there is a large amount of time to recalculate and adjust the optimal observation site for the new target. Therefore, the existing methods are all optimized for the fixed trajectory of a certain target. At the same time, the distance of the missile target is relatively close compared with the space target. Therefore, each method does not pay too much attention to the influence of the action distance on the observability and focuses the key point on the measurement accuracy. The existing methods cannot provide good support for the site selection of space target surveillance equipment.

[0005] In recent years, a great deal of research has been conducted on the optimal layout of optoelectronic theodolites. Zhou Hui, in the research "Study on the Optimal Layout Method of Range Optoelectronic Theodolites", taking missile range measurement as the background and the optimal selection of theodolite site in the range as the goal, with the principle of improving the measurement accuracy at key points of the system and maximizing the potential of the optical measurement system, presented an optimal layout scheme. This scheme is a guiding method for theodolite site selection. However, the target it focuses on is the missile. At the same time, the method proposed only has good observation effects for a certain batch of fixed ballistic targets. When the ballistic of the target to be observed changes, the optimal site needs to be recalculated.

[0006] The existing patent CN111832165A, "A Method and Device for Optimizing the Layout of Measurement and Control Equipment", provides a method to make the distribution of intersection measurement errors uniform and the overall intersection measurement accuracy the highest during the entire observation process. Taking measurement accuracy, tracking accuracy, and backlight conditions as constraints, an optimal layout scheme is given using the adaptive genetic algorithm. This patent focuses on a missile target with a pre-given ballistic. When the target ballistic changes, the site needs to be recalculated.

[0007] Space target surveillance equipment also needs to present a site selection method. In response to this demand, the present invention proposes a method for selecting the site of an optical measurement device based on the optimal observation efficiency, and this method is a site selection method for space target surveillance. Different from the existing site optimization methods for missiles, space target surveillance equipment needs to continuously monitor and measure a large number of satellites and cannot frequently change the site. Therefore, this method presents a method for the comprehensive optimal observation site applicable to a large number of space targets to be observed. Summary of the Invention

[0008] In order to solve problems such as the existing site selection methods only being applicable to the observation of fixed ballistic targets and needing to recalculate the optimal site when the ballistic of the target to be observed changes, the present invention provides a system and method for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency.

[0009] A system for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency, the system includes a preset information input unit, a target orbit simulation unit, an observability evaluation unit, an intersection simulation unit, an observation efficiency evaluation unit, and a site recommendation unit;

[0010] The preset information input unit is used to input space target orbit information, the position information of each site, the number of optical measurement devices to be deployed, the detection capabilities of each optical measurement device, the information of the pre-observation time period, the position of the alternative site or the range of site selection when there is no alternative site; according to the input alternative site and the number of optical measurement devices, all layout information is given through traversal;

[0011] The target orbit simulation unit simulates the target orbits of each space target within a given time period according to the space target orbit information input in the preset information input unit; and calculates the polar coordinate information of each space target relative to each observation point within the observation time period through coordinate transformation, that is: azimuth, pitch, and distance value.

[0012] The observability evaluation unit evaluates the observability of each time point according to the polar coordinate information of each space target relative to each observation point obtained by the target orbit simulation unit and the action distance of the optical measurement equipment under different sky light backgrounds and the solar angle, and records the observable arc segments of all space targets to be observed at different observation points.

[0013] The rendezvous simulation unit calculates the rendezvous duration of each station layout plan according to the observable arc segments obtained by the observability evaluation unit and the station site positions input by the preset information input unit; and simultaneously statistically analyzes the rendezvous observation efficiency at different rendezvous angles with reference to the observation efficiency weight table.

[0014] The observation efficiency evaluation unit respectively statistically analyzes the total observation duration, the total rendezvous duration, and the rendezvous comprehensive score of the space targets to be observed under multiple station layout combinations, and obtains the optimal station layout selection.

[0015] The method for selecting the site of an optical measurement equipment for space targets based on the optimal observation energy efficiency is realized by the system for selecting the site of an optical measurement equipment for space targets based on the optimal observation energy efficiency, and the specific process of this method is as follows:

[0016] Step 1: Calculate the observable arc segments of each target relative to the station site.

[0017] Step 2: The principle of space target rendezvous measurement and the calculation of the total rendezvous duration.

[0018] Step 3: The observation efficiency weights at different rendezvous angles.

[0019] Step 4: The comprehensive measurement of the observation efficiency.

[0020] Step 5: Site recommendations in the case of alternative station sites.

[0021] The beneficial effects of the present invention:

[0022] The site selection method described in the present invention fully considers the action distance of the equipment under different sky background brightnesses, and the optimization focuses on the total observation duration of multiple observation equipment for space targets, the total rendezvous duration of multiple stations, and the rendezvous angle distribution. The present invention quantitatively provides means and basis for the site selection of new space target surveillance equipment.

[0023] In view of the problem that the current site selection method only targets range ballistic missiles, the present invention proposes a site optimization method for space target measurement, which not only considers the measurement effect of a single ballistic trajectory, but statistically analyzes a large number of space targets to be observed, and gives a comprehensive optimal site selection scheme.

[0024] For the space target measurement of optical measurement equipment, the site selection is mostly considered from a qualitative perspective and designed from the perspective of optimal observation efficiency, and the effects of different station layout schemes can be quantitatively compared.

[0025] The present invention can solve the problem of site recommendation in the case of no alternative sites. By constructing an optimization function to be optimized based on the criterion of optimal observation efficiency, the particle swarm optimization algorithm is used to search for the optimal station layout scheme within the given station layout area, providing a theoretical basis for the determination of subsequent sites. Brief Description of the Drawings

[0026] Figure 1 is the principle block diagram of the method for selecting the site of the optical measurement equipment for space target measurement based on the optimal observation energy efficiency according to the present invention;

[0027] Figure 2 is the flow chart of the method for selecting the site of the optical measurement equipment for space target measurement based on the optimal observation energy efficiency according to the present invention;

[0028] Figure 3 is the schematic diagram of the conversion relationship between coordinate systems;

[0029] Figure 4 is the schematic diagram of the principle of space target intersection measurement. Detailed Embodiment

[0030] Combined with Figures 1 to 4 This embodiment is described. The system for selecting the site of the optical measurement equipment for space target measurement based on the optimal observation energy efficiency is composed of multiple functional units. These functional units cooperate with each other to complete the final optimal site selection, and the working sequence between the units is as Figure 1 shown. Now, each unit is introduced:

[0031] Preset information input unit 101;

[0032] This unit completes the function of pre - period information input. To obtain the site corresponding to the optimal observation performance, it is necessary to provide the orbital information of the space targets concerned by the user, the number of optical measurement equipment to be deployed, the detection capabilities of each optical measurement equipment, the information of the pre - observation time period, the location of alternative sites or the range of site selection when there are no alternative sites. According to the input alternative sites and the number of equipment, all possible station layout situations are given through traversal, and then the observation efficiency of each situation is evaluated subsequently.

[0033] Target orbit simulation unit 102;

[0034] Based on the spatial target orbit information input in the preset information input unit 101, this unit simulates and deduces the target orbits of each target within a given time period. And through coordinate transformation, the polar coordinate information of each target relative to each observation point within the observation time period is given, that is, azimuth, pitch, and distance information.

[0035] Observability evaluation unit 103;

[0036] Based on the azimuth, pitch, and distance information of the target relative to the measurement station given by the target orbit simulation unit 102, this unit evaluates the observability at each time point considering the operating distance of the equipment under different sky backgrounds and the problem of avoiding the solar angle, and records the observable arc segments of all targets to be observed at different observation points.

[0037] Rendezvous simulation unit 104;

[0038] Based on the principle of rendezvous measurement and the influence of the rendezvous angle on the positioning accuracy, this unit gives an observation efficiency weight value under different rendezvous angles. For each spatial target to be observed, this unit considers whether there is a rendezvous situation in the observable arc segment reserved by the observability evaluation unit 103, and calculates the total rendezvous duration of each target within the given observation time period under various station layout combinations. At the same time, the rendezvous observation efficiency under different rendezvous angles is statistically analyzed with reference to the observation efficiency weight table;

[0039] Observation efficiency evaluation unit 105;

[0040] Statistically analyze the total measurement duration, total rendezvous duration, and rendezvous comprehensive scoring situation of the spatial targets to be observed under various station layout combinations respectively, and give the optimal station layout selection.

[0041] Station site recommendation unit 106;

[0042] When the preset information input unit 101 does not input alternative station sites, it is necessary to select within the given station site selection range according to the equipment quantity information. The present invention constructs an optimization function to be optimized based on the observation duration, rendezvous duration, and rendezvous comprehensive scoring situation, and uses the particle swarm optimization algorithm to perform iterative optimization within the given station site selection range, and finally gives a set of optimal solutions for site selection, providing guiding significance for the final selection of the station site.

[0043] Specific implementation method two. Combine Figures 1 to 4 Describe this implementation method, a method for selecting the site of an optical measurement device for spatial targets with optimal observation efficiency, and the flowchart is as Figure 2 shown.

[0044] 1. Calculate the observable arc segments of each target relative to the station site

[0045] According to the target orbit information, the location information of each station, and the preset observation time period information provided by the preset information input unit 101, the target orbit simulation unit 102 uses the SGP4 / SDP4 model to calculate the azimuth, pitch, and distance values of each space target to be observed relative to the alternative site at each moment within the preset future time period.

[0046] Two-line orbital elements, developed by the North American Air Defense Command (NORAD), are Keplerian root orbital data that can predict the position of space flight targets based on the general perturbation theory. The two-line orbital elements consider the influence of various space factors, and the data uses a specific method to remove the periodic perturbation terms. In order to make the calculation results more accurate, a prediction model that reconstructs these removed periodic perturbation terms using the same method must be used. Therefore, the prediction model selects the SGP4 / SDP4 (Simplified General Perturbation Version 4 / Simplified Deep-space Perturbation Version 4) model released by NORAD. The SGP4 model is an analytical model for time input and is more suitable for low Earth orbit satellites with a period less than 225 minutes. After combining the TLE initial values, the position of low Earth orbit satellites at any time can be calculated. The SDP4 model is suitable for medium and high Earth orbit satellites with a period greater than 255 minutes. Similarly, after combining the TLE initial values, the position of low Earth orbit satellites at any time can be calculated.

[0047] The satellite position calculated using the SGP4 / SDP4 model is in the coordinate system of True Equator True Equinox (TEME). However, the observability judgment requires the pitch angle information of the space target to be observed relative to the site. Therefore, a coordinate system conversion is required.

[0048] The steps to convert the TEME coordinate system to the Range-Azimuth-Elevation (RAE) coordinate system for observing relative to the site are as follows: First, find the position vector in the TEME coordinate system through the TLE, and obtain the rotation matrices Rx, Ry, and Rz. After using the relevant formulas to find the corresponding position vector in the geocentric inertial coordinate system (J2000 coordinate system), convert it to the corresponding position vector in the Earth-Centered Earth-Fixed (ECEF) coordinate system, and finally convert it to the RAE value relative to the observation station. The steps of the coordinate conversion are as Figure 3 shown.

[0049] a) Conversion between TEME coordinate system and J2000 coordinate system

[0050] Let the position vectors in the TEME coordinate system and the J2000 coordinate system be respectively and Then The calculation formula of is:

[0051]

[0052] where R i (θ) is the rotation matrix, representing a rotation of θ angle around the i-axis, P and N are respectively the precession matrix and the nutation matrix, and the calculation formulas of P, N, and EQ are respectively:

[0053] P = R z (ξ)R y (-θ)R z (Z)

[0054]

[0055]

[0056]

[0057] where ξ, θ, Z are precession parameters, is the mean obliquity of the ecliptic, ΔΨ 1980 is the nutation in longitude, ε is the obliquity of the ecliptic, Ω is the mean longitude of the Moon, and the expressions are respectively:

[0058] ξ = 2306″.2181T + 0″.30188T 2 + 0″.017998T 3

[0059] θ = 2004″.3109T + 0″.42665T 2 + 0″.041833T 3

[0060] Z = 2306″.2181T + 1″.09468T 2 + 0″.018203T 3

[0061] Ω = 125.04452222° - 6962890.5390″T + 7.455T 2 + 0.0008T 3

[0062]

[0063]

[0064] where \(T\) is the number of Julian centuries from epoch J2000 to the observation epoch \(t\), \(\Delta\Psi\) and \(\Delta\varepsilon\) are the nutation in longitude and the nutation in obliquity respectively, and their calculations are from the nutation series given by IAU1980. The nutation series and the calculation formula for \(T\) are as follows:

[0065] \(\Delta\Psi\) 1980 =\(\Delta\Psi+\delta\Delta\Psi\) 1980

[0066]

[0067] a p (T)=k 1 a 1 +k 2 a 2 +k 3 a 3 +k 4 a 4 +k 5 a 5

[0068]

[0069] where \(JD(t)\) is the Julian day at the observation epoch \(t\), \(A\) i , \(B\) i , \(A\) i ′, \(B\) i ′, \(K\) i are the values in the nutation series of order 106 respectively, \(a\) 1 is the mean anomaly of the Moon, \(a\) 2 is the mean anomaly of the Sun, \(a\) 3 is the mean lunar distance from the ascending node, \(a\) 4 is the mean angular distance between the Sun and the Moon, \(a\) 5 =\(\Omega\) is the mean longitude of the Moon, and its value is obtained from the following matrix:

[0070]

[0071] b) Transformation between the J2000 coordinate system and the ECEF coordinate system;

[0072] Let the position vectors in the ECEF coordinate system and the J2000 coordinate system be and respectively. Then the relationship between the two is:

[0073]

[0074] where \(P\), \(N\), \(B\) 2 , \(B\) 1 are the precession, nutation, Earth rotation, Earth polar motion matrices from the inertial system to the Earth-fixed system respectively, and all play the role of coordinate transformation.

[0075] where the calculation formulas for P and N are the same as those described in a), B 2 and B 1 The calculation formulas are as follows:

[0076] B 2 = R Z (-GST)

[0077] B 1 = R x (Y p ) R y (X p )

[0078] GST = GMST + ΔΨcosε A + 0″.000063sin2Ω

[0079] where R x , R y , R z , ΔΨ, Ω are the same as those described in a), X p , Y p are polar motion values, and the values can be obtained from the IERS Notes. GMST is the Greenwich mean sidereal time at the observation instant.

[0080] c) Convert the ECEF coordinate system to the RAE coordinate system relative to the observation station;

[0081] Let the position vector The coordinates in the ECEF coordinate system be P(X, Y, Z), and the observation distance, azimuth, and elevation angle corresponding to its relative observation station site S(B, L, H) are R, A, and E, respectively.

[0082]

[0083] A = arctan(z t / x t ) * 180 / π

[0084] E = arcsin(y t / R) * 180 / π

[0085] where:

[0086] x t = (-sinB * cosL * (X - x g ) - sinB * sinL * (Y - y g ) + cosB * (Z - z g ))

[0087] y t = (cosB * cosL * (X - x g) + cosB * sinL * (Y - y g ) + sinB * (Z - z g ))

[0088] z t =(-sinL * (X - x g ) + cosL * (Y - y g ))

[0089] x g =(N + H) * cosB * cosL

[0090] y g =(N + H) * cosB * sinL

[0091] z g =(N * (1 - e 2 ) + H) * sinB

[0092]

[0093] a is the semi - major axis of the selected Earth ellipsoid model, and e 2 is the corresponding curvature of the selected Earth ellipsoid model. The parameter values can be found according to the coordinate system used.

[0094] Substitute the two - line orbital elements of all space targets to be observed into the SGP4 / SDP4 model. Using the SGP4 / SDP4 model, the azimuth, elevation, and distance information of the space targets to be observed relative to the alternative site addresses at any time within a certain future time can be predicted. According to the operating distance of the equipment recorded by the preset information input unit 101, ensuring that the operating distance is greater than the target distance and the elevation is greater than 0°, the observable arcs for each space target under each alternative site address are preliminarily screened.

[0095] The above - preliminarily selected observable arcs do not consider the influence of the sun on the observation performance of the equipment (when the angle between the optical axis of the equipment and the sun is too small, it will affect the imaging effect of the equipment and the target recognition and detection cannot be completed. At the same time, working in the environment of direct sunlight for a long time will burn the detector).

[0096] The observability evaluation unit 103 should discard the arcs with an angle less than 20° between the target - equipment site - sun within the already selected observable arcs (the sun cannot be directly viewed) to protect the detector. At the same time, the operating distance of the optical measurement equipment for space targets is related to the sky background brightness. Therefore, according to the detection distance of the equipment at each preset moment, the observable arcs are further screened.

[0097] The observable arcs screened through the above steps are recognized as the effective arcs that can finally detect the target.

[0098] II. Principles of Space Target Rendezvous Measurement and Calculation of Total Rendezvous Duration; Principles of Multi-Station Rendezvous of Space Targets are as follows Figure 4 As shown, by using the single-station angle measurement results of two optical measurement devices and performing spatial geometric calculations, the three-dimensional position of the final target can be calculated. The algorithms for solving this model mainly include: the "L" formula or "K" formula method, and the line-line intersection positioning method using the least squares solution. When the two devices can jointly measure the target and the formed intersection angle is within the range of 30° - 150°, the intersection positioning result can be accepted. The total duration of a target being rendezvous measured is the duration that meets the above conditions.

[0099] III. Observation Efficiency Weights at Different Intersection Angles;

[0100] Based on the principles of space target rendezvous measurement presented, through rendezvous measurement, the deficiency that a single optical measurement device can only perform angle measurement is made up for, and the absolute position information of the space target can be obtained. The rendezvous result has high precision, which is beneficial for the center's final cataloging and orbit determination of space targets. Therefore, the rendezvous duration is an important indicator for measuring the overall observation efficiency of optical measurement devices. However, the positioning precision is different at different intersection angles. The schematic diagram of the intersection angle is as follows Figure 4 As shown, the intersection precision is the highest when the intersection angle is 90°, and the intersection precision decreases as the intersection angle moves away from 90°. To improve the calculation efficiency of the method for selecting the site of this space target measurement station, the influence of the intersection angle on the measurement precision is evaluated at intervals of 10°. Finally, the rendezvous simulation unit 104 gives the observation efficiency weights at different intersection angles. As shown in Table 1: Selection of Observation Efficiency Weights at Different Intersection Angles.

[0101] Table 1

[0102]

[0103]

[0104] IV. Comprehensive Measurement of Observation Efficiency

[0105] When rendezvous measurement cannot be completed, the angle measurement data of a single device is still important. The center can comprehensively utilize the measurement information of the radar and other data processing methods, and use the observed angle information of a single device to complete target orbit determination. When there is a possibility of rendezvous measurement in the station layout plan, the duration of rendezvous and the distribution of intersection angles need to be considered as factors for measuring the effectiveness of the station layout plan.

[0106] The selection of the station site ultimately depends on the observation efficiency of each plan. The observation efficiency is comprehensively affected by the following factors: 1. The total observation duration of each device in the system; 2. The total rendezvous duration of multiple devices; 3. The comprehensive scoring of the intersection angle distribution.

[0107] Observation efficiency evaluation unit 105, and the finally used observation efficiency evaluation function is as follows:

[0108]

[0109] In the above formula, k is the current scheme number, and N is the number of space targets used in this evaluation.

[0110] f 1 (i) The optional values are 0 and 1. When the total single-station observation duration of the current scheme for space target i is the longest compared with other schemes, this scheme takes 1, and the rest of the schemes take 0.

[0111] f 2 (i) The optional values are 0 and 1. When the total rendezvous duration of the current scheme for space target i is the longest compared with other schemes, this scheme takes 1, and the rest of the schemes take 0.

[0112] f 3 (i) The optional values are 0 and 1. When the result of multiplying the rendezvous duration of the current scheme for space target i by the weight of the corresponding rendezvous angle interval (Table 1) is the largest, this scheme takes 1, and the rest of the schemes take 0. f 3 (i) It is calculated by the rendezvous simulation unit 104.

[0113] After traversing and counting all the schemes, the scheme with the highest score can be obtained. The station layout selection of this scheme is the final station layout scheme considered from the perspective of the optimal observation efficiency.

[0114] V. Station site recommendation without alternative station sites;

[0115] When no alternative station sites are given, the station site recommendation unit 106 selects alternative station sites within the given station site selection range. First, the pre-specified station site selection range is divided into grids at an interval of 10 km, and the intersection points of the grids are the alternative station sites where the station site can be selected. In the case of no alternative station sites, the present invention no longer uses the traversal method to generate all the station layout schemes, but constructs an optimization function to be optimized (Formula 1) based on the total observation duration, the total rendezvous duration, and the rendezvous comprehensive scoring situation, and uses the particle swarm optimization algorithm to perform iterative optimization within the intersection range of all grids, and finally gives a set of optimal solutions for site selection, providing guiding significance for the final selection of the station site.

[0116] The particle swarm optimization algorithm is a stochastic optimization algorithm. It is initialized as a group of random particles. The particles in the solution space jointly determine their movement speed and direction according to their own and group information, and search for the optimal solution through iteration. When iteratively solving, each particle updates its speed and position by tracking two "optimal solutions", and the update method is as follows:

[0117]

[0118]

[0119] Where: w is the inertia weight; c 1 , c 2 are acceleration factors; r 1 , r 2 are random numbers between (0, 1); is the d-th component of the optimal position vector of the i-th particle at the k-th moment; is the d-th component of the optimal position vector of the population at the k-th moment.

[0120] The parameter selection of the particle swarm optimization algorithm is as follows: the population number is 60, the inertia weight factor w = 0.9 and linearly decreases with the number of iterations until it reaches 0.4, the learning factor c 1 = c 2 = 2, the maximum velocity v max is 1 / 10 of the total number of intersection points in the longitude and latitude directions after gridification, and the number of iterations is 2000 times.

[0121] Based on selecting the optimal solution from alternative solutions, the method described in this embodiment proposes a scheme for searching the optimal station location without alternative station sites by using the particle swarm optimization algorithm. Using the optimal observation efficiency as the function to be optimized, the design of the optimal station layout scheme can be completed within the given station location selection area, providing a theoretical basis for determining the final station layout scheme.

[0122] Compared with the existing station location selection methods, the method described in this embodiment changes the target type from range missiles to space targets, and the number of targets considered also changes from the trajectory of a single target to a large number of space targets with different orbital altitudes and orbital inclinations. Therefore, when considering the observation efficiency of each site selection scheme, the overall effect of observing multiple space targets under different site selection schemes is evaluated in the present invention, rather than evaluating a single target or a fixed missile trajectory.

[0123] This embodiment evaluates the advantages and disadvantages of each set of station location schemes from the perspective of observation efficiency, not only considering the duration of the observable arc segment of a single device, but also considering the entire observation system. Since higher-precision spatial positions can be obtained when multiple devices perform intersection measurement, the intersection duration of multiple stations is also listed as an important index of observation efficiency. From the principle analysis of intersection measurement, the final data accuracy obtained with different intersection angles is different. According to the different intersection angles, the present invention gives the corresponding weight values. The closer the intersection angle is to 90°, the higher the intersection accuracy and the greater the weight value at this time. Therefore, the distribution of intersection angles is also used as an index of observation efficiency. The final observation efficiency consists of the total observation duration of each station, the total intersection duration, and the distribution of intersection angles.

Claims

1. A system for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency, characterized in that: The system includes a preset information input unit, a target orbit simulation unit, an observability evaluation unit, a rendezvous simulation unit, an observation efficiency evaluation unit, and a site recommendation unit; The preset information input unit is used to input space target orbit information, the location information of each site, the number of optical measurement devices to be deployed, the detection capabilities of each optical measurement device, the information of the pre-observation time period, the location of the alternative site or the range of site selection when there is no alternative site; according to the input alternative site and the number of optical measurement devices, all station layout information is given by traversal; The target orbit simulation unit simulates the target orbits of each space target within a given time period according to the space target orbit information input in the preset information input unit; And through coordinate transformation, calculate the polar coordinate information of each space target relative to each observation point during the observation time period, that is: azimuth, elevation, and distance values; The observability evaluation unit evaluates the observability of each time point according to the polar coordinate information of each space target relative to each observation point obtained by the target orbit simulation unit and the action distance of the optical measurement device under different sky light backgrounds according to the solar angle, and records the observable arc segments of all space targets to be observed at different observation points; The rendezvous simulation unit calculates the rendezvous duration of each station layout plan according to the observable arc segments obtained by the observability evaluation unit and the site location input by the preset information input unit; at the same time, refer to the observation efficiency weight table to count the rendezvous observation efficiency under different rendezvous angles; The observation efficiency evaluation unit respectively counts the total observation duration, the total rendezvous duration and the comprehensive rendezvous score of the space targets to be observed under multiple station layout combinations, and obtains the optimal station layout selection.

2. The system for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency according to claim 1, characterized in that: It further includes a site recommendation unit: when the preset information input unit does not input an alternative site, it selects within the given site selection range according to the information of the number of optical measurement devices.

3. A method for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency, characterized in that: This method is implemented by the system for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency described in any one of claims 1-2. The specific process of this method is as follows: Step 1, calculate the observable arc segments of each target relative to the site; Step 2, calculate the principle of space target rendezvous measurement and the total rendezvous duration; Step 3, the observation efficiency weights under different rendezvous angles; Step 4, the comprehensive measurement of observation efficiency; Step 5, site recommendation in the case of alternative sites.

4. The method for selecting the site of an optical measurement device for space target measurement based on the optimal observation energy efficiency according to claim 3, characterized in that: In step 1, according to the target orbit information, each station position information, and the pre-observation time period information input by the preset information input unit, the target orbit simulation unit calculates the azimuth, elevation, and distance values of each space target to be observed relative to the alternative site addresses within the given time period through the SGP4 / SDP4 model; According to the operating distance of the equipment recorded by the preset information input unit, the observable arc segments of each space target at each observation point are preliminarily calculated; The observable arc segments are finally calculated by the observability evaluation unit according to the solar angle and the operating distance of the optical measurement equipment under different sky light backgrounds.

5. The method for selecting the space target measurement site address of the optical measurement equipment based on the optimal observation energy efficiency according to claim 4, characterized in that: In step 1, for the preliminarily calculated observable arc segments, it is ensured that the operating distance of the equipment is greater than the target distance and the elevation angle requirement is greater than 0°.

6. The method for selecting the space target measurement site address of the optical measurement equipment based on the optimal observation energy efficiency according to claim 4, characterized in that: It further includes the step of selecting alternative site addresses within the given site address selection range by the site address recommendation unit when no alternative site addresses are given. The given site address selection range is divided into grids at intervals of 10 km, and the intersection points of the grids are used as alternative site addresses for site address selection.

7. The method for selecting the space target measurement site address of the optical measurement equipment based on the optimal observation energy efficiency according to claim 4, characterized in that: In step 4, the observation energy efficiency evaluation function used by the observation energy efficiency evaluation unit is as follows: In the formula, k is the current scheme number, and N is the number of space targets used in this evaluation; f 1 The value of (i) is 0 or 1. When the total single-station observation duration of the current station layout plan for space target i is the longest, the value of this plan is 1, and the values of the other station layout plans are 0; f 2 (i) When the selected value is 0 or 1, when the total rendezvous duration of the current station layout plan for space target i is the longest, the station layout plan takes 1, and the rest of the station layout plans take 0; f 3 (i) The selection value is 0 or 1. When the intersection time of the current station layout plan for the space target i is multiplied by the weight of the corresponding intersection angle interval and the final weighted result is the largest, this station layout plan takes 1, and the rest of the station layout plans take 0; f 3 (i) Calculated and given by the intersection simulation unit; After traversing and counting all the station layout schemes, the station layout scheme with the highest score is obtained. The selection of this station layout scheme is the final station layout scheme considered from the perspective of the optimal observation energy efficiency.

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