Automatic site calibration system and method for airborne radar and optical detection equipment

Abstract

The invention discloses an automatic site calibration system and method for airborne radar and optical detection equipment. The method comprises the following steps: determining the type and quantity requirements of calibration equipment and site constraint conditions according to calibration task parameters; a calibration service planning unit of the calibration service management module generates a calibration equipment position and a waypoint planning result; the calibration service management module controls the detection equipment to complete calibration equipment imaging according to a waypoint planning result; parameters of the calibration equipment are synchronously measured in the imaging process, and environmental parameters are collected through environmental parameter collection equipment; the ground preprocesses the imaging original data to obtain an SAR image of the radar detection equipment and an optical image of the optical detection equipment; inputting the image data into a calibration service management module, identifying the position of calibration equipment in the image and sending the position to a calibration processing module; the calibration processing module calculates and outputs a calibration coefficient K based on the position of the calibration device in the image in combination with the environmental parameters and the calibration device parameters.

Description

An automated site calibration system and method for airborne radar and optical detection equipment Technical Field

[0001] This invention relates to an automated site calibration system and method for airborne radar and optical detection equipment, used for site calibration planning and automatic calculation of calibration coefficients for airborne radar and optical detection equipment, belonging to the field of detection equipment and intelligent control. Background Technology

[0002] The calibration field is mainly used for on-board and airborne detection equipment to carry out on-site calibration, periodic performance monitoring, parameter calibration and authenticity verification of on-orbit or mission-based detection equipment, and to provide good measurement accuracy assurance for the detection equipment.

[0003] Currently, most calibration fields are geared towards spaceborne detection equipment. These fields are primarily used for satellite calibration and are characterized by large construction scale, abundant site resources, large-sized calibration equipment, diverse types of calibration equipment, limited distribution of calibration sites, and stable satellite transit conditions. In terms of operational mode, they have gradually evolved from early site-based calibration primarily involving manual intervention to automated calibration. Airborne detection equipment operates under significantly different conditions. Its flight altitude is much lower than that of satellites, making it difficult to maintain consistent altitude, speed, and natural environment during each transit. Airports are typically far from calibration fields, resulting in insufficient resource support. They usually require independent storage and power supply, making it difficult to use active calibration equipment. For airborne detection equipment, on the one hand, there are fewer detection devices used for high-precision measurements, leading to lower calibration requirements; on the other hand, calibration is usually completed by temporarily deploying a combination of calibration equipment with dimensions meeting the requirements in flat areas. Therefore, research on automated calibration for airborne equipment is relatively limited. Summary of the Invention

[0004] The technical problem solved by the present invention is to overcome the shortcomings of the prior art and provide an automated site calibration system and method for airborne radar and optical detection equipment. By automatically calculating the deployment position of the calibration equipment and automatically identifying the calibration equipment in the positioning image, the invention overcomes the previous manual calibration of equipment and the large amount of manual labor required to select calibration equipment in the image, and realizes the capability of automatic site calibration of radar and optical detection equipment.

[0005] The technical solution of this invention is as follows: Firstly, an automated site calibration system for airborne radar and optical detection equipment is provided, comprising: calibration equipment, calibration equipment measuring instruments, environmental parameter acquisition equipment, a calibration business management module, and a calibration processing module; wherein: the calibration equipment is used for calibrating the detection equipment and outputs calibration equipment parameters to the calibration processing module; the calibration equipment measuring instruments are used for measuring the time-varying parameters of the calibration equipment and outputting them to the calibration processing module; the instruments output the time-varying parameters of the calibration equipment's position, radiance, and temperature to the calibration processing module; the environmental parameter acquisition equipment is used for acquiring environmental parameters at the measurement time and outputting them to the calibration processing module; the calibration business management module is used for calibration business planning, detection... The detection equipment monitoring and target detection and identification system includes: a calibration service planning unit, a detection equipment monitoring unit, and a target detection and identification unit. The calibration service planning unit receives calibration task parameters from the detection equipment, generates calibration equipment position and waypoint planning results, and outputs them to the detection equipment monitoring unit. The detection equipment monitoring unit controls the detection equipment to image the calibration equipment and outputs the image data acquired by the detection equipment to the target detection and identification unit and the calibration processing module. The target detection and identification unit identifies the position of the calibration equipment in the image data. The calibration processing module is used for calibration coefficient calculation, receives image data, calibration equipment parameters, and environmental parameters output by the detection equipment monitoring unit, generates calibration coefficients, and outputs them to the detection equipment.

[0006] Preferably, the calibration equipment parameters output by the calibration equipment to the calibration processing module include: the position, azimuth, altitude, RCS, dynamic temperature, radiance, emissivity, and reflectivity of each calibration equipment; the environmental parameters output by the environmental parameter acquisition equipment to the calibration processing module include: temperature profile, humidity profile, pressure profile, water vapor content, aerosol content, wind speed, wind force, wind direction, solar altitude angle, solar azimuth angle, and solar irradiance; the calibration task parameters include: flight altitude, observation distance, detection equipment resolution, and operating spectrum.

[0007] Preferably, in the target detection and recognition unit, the YOLOV5 algorithm is used to detect and identify the position of the calibration device in the image; after the system generates calibration coefficients, the calibration coefficients are used to correct the image data, and the corrected image data is used to optimize the YOLOV5 algorithm.

[0008] Secondly, an automated site calibration method for airborne radar and optical detection equipment is provided, comprising: determining the type and quantity requirements of calibration equipment and site constraints based on calibration task parameters; the calibration business planning unit of the calibration business management module generating the location of the calibration equipment based on the type, quantity requirements, and site constraints; obtaining waypoint planning results for the detection equipment based on the location of the calibration equipment; the detection equipment monitoring unit of the calibration business management module controlling the detection equipment to complete the imaging of the calibration equipment according to the waypoint planning results, and sending the raw imaging data to ground storage; simultaneously measuring the parameters of the calibration equipment during the imaging process, and collecting environmental parameters through environmental parameter acquisition equipment; and ground... The raw imaging data is preprocessed to obtain SAR images from radar detection equipment, optical images from optical detection equipment, and imaging auxiliary data. The image data and imaging auxiliary data are input into the target detection and recognition unit of the calibration service management module to identify the position of the calibration equipment in the image and send it to the calibration processing module. Based on the position of the calibration equipment in the image and combined with environmental parameters, the calibration processing module determines the gray value Hi of the radiation power of each calibration equipment observed by the optical detection equipment in the gray space, and determines the radiation / scattering physical quantity Ri of the apparent position of the radar detection equipment by combining the calibration equipment parameters. Using Hi, Ri, and the background noise of the detection equipment, the calibration coefficient K is calculated and output.

[0009] Preferably, based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, the particle swarm optimization algorithm is used to generate the calibration equipment positions. Specifically: S2-1, Define the two-dimensional spatial coordinates of the calibration equipment as the particle positions; Based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, initialize the number of particles, initial positions, velocities, weight values, and the upper limit of the number of iterations; S2-2, Input the positions of the particles into the objective function to calculate the objective function F0, and construct the fitness value F using the objective function F0 and the penalty function value G; S2-3, Determine the individual optimal and global optimal values ​​in the particle swarm by optimizing the fitness value F, with the optimization objective being min F(X); Adjust the weight values ​​wt of the particle swarm optimization algorithm using a linear decreasing strategy, update the particle velocity value V based on the adjusted weight values ​​wt, and update the particle position X based on the updated particle velocity value, return to step S2-2 to continue iterating until the upper limit of the number of iterations is reached, and output the final calibration equipment position X.

[0010] Preferably, the fitness value F is:

[0011] Where: the objective function F0 represents the area or perimeter formed by the coordinates of all current calibration devices; the penalty function value G is determined by the inner product of the penalty vector g and the penalty coefficient p: G = g p=[g1,g2] [p1,p2]T The penalty vector g includes a scaling satisfaction penalty function component g1 and a field boundary violation penalty function component g2, and the penalty coefficient p includes a first penalty coefficient p1 and a second penalty coefficient p2.

[0012] Preferably, when determining the penalty vector g: the position of each particle is verified. If the position of the current particle meets the calibration requirements, g1 is 0; otherwise, g1 is 1. The calibration requirements are: the spacing requirements between calibration devices. The spacing between radar calibration devices should be no less than P1 pixels, and the spacing between optical calibration devices should be no less than P2 pixels. The physical scale of the spacing between calibration devices is determined by combining the resolution of the radar detection device and the resolution of the optical detection device. The current position of the calibration device is compared with the field boundary. For particles that have not exceeded the field boundary, g2 is recorded as 0. For particles that have exceeded the field boundary, the Euclidean distance between the particle and the field boundary is used as the field boundary crossing scale, and the sum of the boundary crossing scales of all particles is used as g2.

[0013] Preferably, the imaging auxiliary data includes: the position and attitude of the detection device at the imaging time; before the target detection and recognition unit identifies the position of the calibration device in the image, it filters the image to ensure that the image covers the calibration site; when the target detection and recognition unit identifies the position of the calibration device in the image, it uses the YOLOV5 algorithm to detect the calibration device, and further filters the detection result using the actual position of the calibration device to complete the identification and positioning of the calibration device in the aerial photograph.

[0014] Preferably, when determining the grayscale value Hi of the radiation power of each calibration device observed by the optical detection device in the grayscale space: the calibration processing module uses the local adaptive threshold method to automatically extract the number of pixels and the grayscale value of each pixel of each calibration device in the optical image, and sums the pixels to obtain the total grayscale value observed by the optical detection device for the calibration device, which represents the grayscale value Hi of the radiation power of the calibration device observed by the optical detection device in the grayscale space.

[0015] Preferably, when determining the radiation / scattering physical quantity Ri of the apparent location of the radar detection equipment: based on the calibration mission parameters of the detection equipment and combined with the measured calibration equipment parameters, the radiation / scattering physical quantity Ri of the apparent location of the detection equipment is calculated using a transmission model.

[0016] Compared with the prior art, the present invention has the following advantages: (1) It adopts an improved particle swarm optimization algorithm, with site conditions as constraints and the location and type of calibration equipment as optimization variables, to solve the location of radar / optical system calibration equipment, which can cover radar radiation calibration, radar polarization calibration, and optical radiation calibration; improves the scope of use and layout efficiency of calibration site; (2) It adopts a target detection and recognition algorithm based on the YOLOV5 model, combined with prior information such as the location of calibration equipment, to realize automatic extraction of feature points, positioning of calibration equipment, automatic calculation of scattering / radiation intensity, and further calculation of radar / optical system calibration coefficients, reducing a lot of manual labor such as selecting calibration equipment in the image, and realizing automatic site calibration capability for radar and optical detection equipment. Attached Figure Description

[0017] Figure 1 is a system composition diagram of the present invention; Figure 2 is a schematic diagram of the calibration site layout of the present invention; Figure 3 is a schematic diagram of the calibration equipment location optimization process of the present invention; Figure 4 is a schematic diagram of the raw data to image data processing of the present invention; Figure 5 is a schematic diagram of the raw data to image data processing of the present invention. Detailed Implementation

[0018] This invention proposes an automated site calibration system and method applicable to both airborne radar and optical detection equipment.

[0019] I. Calibration System The calibration system, as shown in Figure 1, mainly consists of hardware and software. The hardware comprises calibration equipment (radar calibration equipment such as trihedral reflectors, 0-degree reflectors, 45-degree reflectors, and 22.5-degree reflectors, as well as optical calibration equipment such as temperature-gradient targets and gray-gradient targets), calibration equipment measuring instruments (spectral measuring instruments, positioning and orientation instruments, etc.), environmental parameter acquisition equipment (microwave radiometers, solar photometers, portable weather stations, etc.), and high-performance servers (data storage devices, data processing devices, etc.). The functional software includes: a calibration business management module (calibration task planning unit, detection equipment monitoring unit, target detection and identification unit, etc.) and a calibration processing module (calibration data processing unit, meteorological data processing unit, etc.). The layout of the calibration site is shown in Figure 2.

[0020] The calibration system includes: calibration equipment, calibration equipment measuring instruments, environmental parameter acquisition equipment, a server, a calibration business management module, and a calibration processing module. Specifically: the calibration equipment is used for calibrating the detection equipment, outputting time-invariant parameters such as the calibration equipment's dimensions and RCS (radar cross section) to the calibration processing module (server). After deployment on-site, the detection equipment images the calibration equipment, generating an image. Combined with parameters collected by the calibration equipment measuring instruments and the environmental parameter acquisition equipment, the processing module calibrates the detection equipment. The calibration equipment measuring instruments measure the time-varying parameters of the calibration equipment, outputting time-varying parameters such as the calibration equipment's location, radiance, and temperature to the calibration processing module (server). The environmental parameter acquisition equipment collects environmental parameters such as atmospheric conditions and illumination at the time of measurement, outputting parameters such as temperature profile, humidity profile, pressure profile, wind speed, wind direction, wind force, and solar radiance to the calibration processing module (server). The server supports the calibration business management and calibration processing software operation, connecting... The system receives parameters and images generated by calibration equipment, calibration equipment measuring instruments, environmental parameter acquisition equipment, and detection equipment, and outputs calibration coefficients to the detection equipment to calibrate it. The calibration business management module runs on the server and is used for calibration business planning, detection equipment monitoring, and target detection and recognition. The calibration business planning unit receives calibration task parameters (flight altitude, observation distance, detection equipment resolution, etc.) from the detection equipment, generates calibration equipment position and flight path planning results, and outputs the flight path planning results to the detection equipment monitoring unit. The detection equipment monitoring unit controls the imaging of the detection equipment and outputs the image data acquired by the detection equipment to the target detection and recognition unit and the calibration processing module.

[0021] The calibration processing module runs on the server, calculates calibration coefficients, receives image data from the monitoring unit of the detection equipment, time-invariant parameters of the calibration equipment, time-varying parameters of the calibration equipment from the measuring instrument of the calibration equipment, and environmental parameters collected by the environmental parameter acquisition device at the measurement time. It generates calibration coefficients and outputs them to the detection equipment. The system relies on ground power supply, communication, security and other basic support. It uses data storage devices to store the original data of the detection equipment, the status data of the calibration equipment, environmental parameter data, etc. It uses data processing equipment to plan and control the calibration route of the detection equipment, receive and display images of the detection equipment, automatically identify and locate the calibration equipment in the images, and automatically calibrate the images of the detection equipment.

[0022] II. The overall workflow of the automated site calibration method for airborne radar and optical detection equipment using a calibration system mainly involves automatically determining the positions of the radar and optical calibration equipment by inputting parameters of the radar and / or optical detection equipment (flight altitude, observation distance, equipment resolution, operating spectrum, etc.) and calibration site conditions (site shape, dimensions, etc.), thus completing the calibration flight path planning for the detection equipment. The system receives raw data from the detection equipment, performs imaging and display, and uses a target detection and recognition algorithm based on prior information from the calibration equipment to automatically identify and locate the equipment. Further calibration processing is then performed on the image data from the detection equipment, achieving fully automated calibration throughout the entire process.

[0023] The detailed steps of the calibration method are as follows: Step 1: Determine the type and quantity requirements of the calibration equipment based on the calibration task.

[0024] First, based on the requirements of the calibration task, determine whether the calibration task is radar calibration or optical calibration, as well as the required equipment specifications and quantity, which are generally determined by the flight altitude, observation distance, and operating spectrum of the detection equipment.

[0025] Subsequently, according to the calibration operation procedures, the spacing between radar calibration devices is generally not less than P1 pixels, and the spacing between optical calibration devices is generally not less than P2 pixels. Specifically: for optical detection equipment, the size of the calibration device in the image is generally required to be not less than 10 pixels, and the size of the calibration device is determined by the observation distance and resolution; for radar detection equipment calibration, the RCS of the calibration device is generally required to meet a signal-to-noise ratio of ≥35dB, and the RCS of the calibration device is related to the size of the calibration device and the operating spectrum of the detection device.

[0026] For radar detection equipment, input parameters such as flight altitude, observation distance, detection equipment resolution, and operating spectrum, and call the radar detection equipment calibration requirement assessment module to generate the calibration equipment type, specifications, and quantity requirements for radar detection equipment calibration.

[0027] For optical detection equipment, input parameters such as flight altitude, observation distance, and detection equipment resolution, and call the calibration requirement assessment module of optical detection equipment to generate the calibration equipment type, specifications, and quantity requirements for optical detection equipment calibration.

[0028] Step 2: Based on the type, specifications, and quantity requirements of the calibration equipment, as well as the site constraints, the particle swarm optimization (PSO) algorithm is used to generate the locations of the calibration equipment. As shown in Figure 3: First, a two-dimensional coordinate vector X (design variable) of the calibration equipment is constructed, the population size N and the number of iterations T are set, and each particle in the population is initialized within the boundary of the site.

[0029] Xi = [xi1,yi1,ti1,xi2,yi2,ti2,...,xij,yij,tij] Vi = [ui1,vi1,ti1,ui2,vi2,ti2,...,uij,vij,tij] where X is the position of an individual particle in the swarm (design variable), V is the velocity of an individual particle in the swarm (change in design variable), i is the i-th particle, j is the j-th calibration device, x is the horizontal axis, y is the vertical axis, and t is the type of calibration device.

[0030] Based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, the particle swarm optimization (PSO) algorithm is used to generate the calibration equipment positions. Specifically: S2-1, Define the three-dimensional spatial coordinates of the calibration equipment as the particle positions; Based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, initialize the number of particles, initial positions, velocities, weights wt, and the upper limit of the number of iterations; S2-2, Input the positions of the particles into the objective function to calculate the objective function, and construct the fitness value F through the objective function F0 and the penalty function value G; The optimization objective is: min F(X) S2-3, Determine the individual optimal and global optimal values ​​in the particle swarm based on the fitness value F, adjust the weights wt of the PSO algorithm using a linear decreasing strategy, update the particle velocity values ​​based on the adjusted weight values, and update the particle positions based on the updated particle velocity values. Return to step S2-2 to continue iterating until the upper limit of the number of iterations is reached, and output the final calibration equipment positions.

[0031] Next, the design variable X is substituted into the objective function to calculate the fitness value F. The fitness value consists of the objective function F0 and the penalty function value G:

[0032] W represents the weighting coefficient; F0 represents the area or perimeter formed by the coordinates of all current calibration equipment positions. The penalty function value is determined by the inner product of the penalty vector g and the penalty coefficient p. The penalty vector consists of the calibration satisfaction penalty function component g1 and the site boundary violation penalty function component g2, and the penalty coefficient consists of the first penalty coefficient p1 and the second penalty coefficient p2.

[0033] G=g p=[g1,g2] [p1,p2] T For radar detection equipment, the current position of each particle (two-dimensional coordinate vector of the calibration equipment) is verified to obtain g1. A value of 0 indicates that the calibration requirement is met, while a value of 1 indicates that the requirement is not met. The calibration requirement is: meeting the spacing requirements of the calibration equipment.

[0034] For optical detection equipment, the current position of each particle (two-dimensional coordinate vector of the calibration equipment) is verified to obtain g1. A value of 0 indicates that the calibration requirement is met, while a value of 1 indicates that the requirement is not met. The calibration requirement is: meeting the spacing requirements of the calibration equipment.

[0035] The difference between the current calibration equipment position and the site boundary (site constraints) is compared. For particles that do not exceed the boundary, g2 is recorded as 0. For particles that exceed the site boundary, the Euclidean distance between the particle and the site boundary is used as the site boundary scale. The boundary scales of all calibration equipment are summed to obtain g2.

[0036] Then, the individual optimality and global optimality of the population are statistically analyzed. The weight wt of the particle swarm optimization algorithm is adjusted using a linear decreasing strategy, the particle velocity values ​​are updated, and the particle positions are further updated to obtain the updated design variable vector.

[0037] Finally, when the number of iterations is reached, the final optimization result X=[x1,y1,t1,x2,y2,t2,...,xj,yj,tj] is obtained. The flight platform's route planning module is then called, and the optimization result is input to obtain the waypoint set W, W=[w1,w2,...].

[0038] Step 3: Control the detection equipment to complete the imaging acquisition of the calibration equipment, and simultaneously complete the acquisition of calibration equipment and environmental parameters on the ground.

[0039] After the aircraft and detection equipment complete the ground inspection, they enter a standby state. After takeoff, under the control of the detection equipment monitoring unit, the aircraft passes through each pre-planned waypoint set W in sequence to image the calibration equipment and obtain the raw data set D'=[D'1,D'2,...].

[0040] On the ground, operators simultaneously collect calibration equipment parameters C and environmental parameters E.

[0041] C=[C1,C2,...,Cj] includes parameters such as the location, orientation, altitude, RCS (radar cross section), dynamic temperature, radiance, emissivity, and reflectivity of each calibration device.

[0042] E=[Etp,Ehp,Epp,Ewt,Eat,Ewv,Ews,Ewd,Eel,Eaz,Esr,...] includes parameters such as local temperature profile, humidity profile, pressure profile, water vapor content, aerosol content, wind speed, wind force, wind direction, solar altitude angle, solar azimuth angle, and solar irradiance.

[0043] Step 4: Complete the calibration data transfer and calibration equipment positioning on the ground.

[0044] First, the raw data is unloaded to a ground-based data storage device via data link or hard drive transfer, where it is processed by the calibration module. As shown in Figure 4, the raw data D' is then decompressed and parsed. For data from radar detection equipment, the imaging module of the radar detection equipment must be called first to process the echo data into an image, thus obtaining a SAR image. For data from optical detection equipment, the image can be obtained directly. Finally, image data D0=[D01,D02,...] and auxiliary data A=[A1,A2,...] are formed. The auxiliary data includes parameters such as position and attitude at the time of imaging.

[0045] Then, as shown in Figure 5, aerial photographs are first screened based on the calibration site location information to ensure that the photographs cover the calibration site. Afterwards, the aerial photographs are input into the target detection and recognition unit of the calibration business management module. The trained and fine-tuned YOLOv5 algorithm is used to perform target detection on the screened image data (aerial photographs). The detection results are further analyzed using the actual location X of the calibration equipment. T Filtering is performed to identify and locate the calibration equipment in the aerial photographs.

[0046] Step 5: Complete the calibration data processing on the ground and obtain the calibration coefficients.

[0047] The calibration processing module uses a local adaptive thresholding method to automatically extract the number of pixels and the gray value of each pixel of each calibration device in the aerial photograph. The total gray value observed by the detection device for the calibration device is obtained by summing the values ​​of each pixel, which represents the magnitude of the radiation power of the calibration device observed by the detection device in the gray space, Hi, where i is the i-th calibration device.

[0048] The meteorological data processing software uses mature commercial software and, by utilizing a transmission model and combining the basic parameters of the calibration task (altitude, distance, operating spectrum, etc.), it extrapolates the radiation / scattering physical quantities Ri at the apparent location of the detection equipment from the actual physical quantities of the calibration equipment in the calibration equipment parameter C.

[0049] The least squares method is used to calculate the calibration coefficient K by combining the gray value Hi of the calibration device observed by the detection device, the physical quantity Ri of the apparent position of the detection device, and the background noise Ni measured by the detection device at the factory.

[0050] Optionally, by combining the calibration coefficient K, radiometric correction can be performed on the image data D1 using mature commercial software to obtain the radiometrically corrected image D1=[D11,D12,...]. Further, by combining the observation geometry (flight altitude, observation distance, etc.) and the imaging model of the detection equipment, geometric correction can be performed on D1 to obtain the geometrically corrected image D2=[D21,D22,...].

[0051] Optionally, to improve the recognition performance of the target detection and recognition software, it supports training the recognition algorithm using data of types such as D0, D1, and D2. For the selected training samples, semi-automatic and manual annotations are performed. The recognition algorithm is then trained on the data processing server, and the updated weights are assigned to the target detection and recognition software for subsequent target detection tasks in calibration equipment.

[0052] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0053] To improve the efficiency of automated field calibration of airborne radar and optical calibration equipment, this invention overcomes the previous reliance on manual calibration and selection of calibration equipment in images by automatically calculating the deployment location of calibration equipment and automatically identifying calibration equipment in the positioning images. This enables automated field calibration of radar and optical detection equipment.

[0054] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. An automated site calibration system for airborne radar and optical detection equipment, characterized in that... include: The system comprises calibration equipment, calibration equipment measuring instruments, environmental parameter acquisition equipment, a calibration business management module, and a calibration processing module. Specifically: the calibration equipment is used for calibrating the detection equipment and outputs calibration equipment parameters to the calibration processing module; the calibration equipment measuring instruments are used to measure the time-varying parameters of the calibration equipment and output them to the calibration processing module; they also output the time-varying parameters of the calibration equipment's location, radiance, and temperature to the calibration processing module; the environmental parameter acquisition equipment is used to collect environmental parameters at the time of measurement and output them to the calibration processing module; the calibration business management module is used for calibration business planning, detection equipment monitoring, and target detection and identification, including: a calibration business planning document. The system comprises a detection equipment monitoring unit, a target detection and identification unit, and a calibration service planning unit. The calibration unit receives calibration task parameters from the detection equipment, generates calibration equipment location and waypoint planning results, and outputs them to the detection equipment monitoring unit. The detection equipment monitoring unit controls the detection equipment to image the calibration equipment and outputs the image data acquired by the detection equipment to the target detection and identification unit and the calibration processing module. The target detection and identification unit identifies the location of the calibration equipment in the image data. The calibration processing module calculates calibration coefficients, receives image data, calibration equipment parameters, and environmental parameters output by the detection equipment monitoring unit, generates calibration coefficients, and outputs them to the detection equipment.

2. The automated site calibration system for airborne radar and optical detection equipment according to claim 1, characterized in that: The calibration equipment parameters output by the calibration equipment to the calibration processing module include: the location, azimuth, altitude, RCS, dynamic temperature, radiance, emissivity, and reflectivity of each calibration equipment; the environmental parameters output by the environmental parameter acquisition equipment to the calibration processing module include: temperature profile, humidity profile, pressure profile, water vapor content, aerosol content, wind speed, wind force, wind direction, solar altitude angle, solar azimuth angle, and solar irradiance; the calibration task parameters include: flight altitude, observation distance, detection equipment resolution, and operating spectrum.

3. The automated site calibration system for airborne radar and optical detection equipment according to claim 1, characterized in that: When the target detection and recognition unit is used, the YOLOv5 algorithm is used to detect and identify the position of the calibration device in the image. After the system generates calibration coefficients, the calibration coefficients are used to correct the image data, and the corrected image data is used to optimize the YOLOv5 algorithm.

4. An automated site calibration method for airborne radar and optical detection equipment, characterized in that... include: The type and quantity requirements of the calibration equipment, as well as the site constraints, are determined based on the calibration task parameters. The calibration business management module's calibration business planning unit generates the location of calibration equipment based on the type and quantity requirements of the calibration equipment and site constraints; and obtains waypoint planning results for the detection equipment based on the location of the calibration equipment. The detection equipment monitoring unit of the calibration service management module controls the detection equipment to complete the calibration equipment imaging according to the waypoint planning results and sends the raw imaging data to the ground storage. During the imaging process, the calibration equipment parameters are measured simultaneously, and environmental parameters are collected through the environmental parameter acquisition equipment. The ground preprocesses the raw imaging data to obtain the SAR image of the radar detection equipment, the optical image of the optical detection equipment, and imaging auxiliary data. The image data and imaging auxiliary data are input into the target detection and recognition unit of the calibration service management module to identify the position of the calibration equipment in the image and send it to the calibration processing module. The calibration processing module determines the grayscale value Hi of the radiation power of each calibration device observed by the optical detection device in the grayscale space based on the position of the calibration device in the image and combined with environmental parameters. It also determines the radiation / scattering physical quantity Ri of the apparent position of the radar detection device based on the calibration device parameters. Using Hi, Ri and the background noise of the detection device, the calibration coefficient K is calculated and output.

5. The automated site calibration method for airborne radar and optical detection equipment according to claim 4, characterized in that: Based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, the particle swarm optimization (PSO) algorithm is used to generate the calibration equipment positions. Specifically: S2-1, Define the two-dimensional spatial coordinates of the calibration equipment as the particle positions; Based on the type, specifications, and quantity requirements of the calibration equipment, as well as site constraints, initialize the number of particles, initial positions, velocities, weight values, and the upper limit of the number of iterations; S2-2, Calculate the objective function by inputting the positions of the particles, and construct the fitness value F using the objective function F0 and the penalty function value G; S2-3, Determine the individual optimal and global optimal values ​​in the particle swarm by optimizing the fitness value F, with the optimization objective being min F(X); Adjust the weight values ​​wt of the PSO algorithm using a linear decreasing strategy, update the particle velocity value V based on the adjusted weight values ​​wt, and update the particle position X based on the updated particle velocity value, returning to step S2-2 to continue iteration until the upper limit of the number of iterations is reached, and output the final calibration equipment position X.

6. The automated site calibration method for airborne radar and optical detection equipment according to claim 4, characterized in that: The fitness value F is: Where: the objective function F0 represents the area or perimeter formed by the coordinates of all current calibration devices; the penalty function value G is determined by the inner product of the penalty vector g and the penalty coefficient p: G = g p=[g1,g2] [p1,p2] T The penalty vector g includes a scaling satisfaction penalty function component g1 and a field boundary violation penalty function component g2, and the penalty coefficient p includes a first penalty coefficient p1 and a second penalty coefficient p2.

7. The automated site calibration method for airborne radar and optical detection equipment according to claim 6, characterized in that: When determining the penalty vector g: the position of each particle is verified. If the position of the current particle meets the calibration requirements, g1 is 0; otherwise, g1 is 1. The calibration requirements are: the spacing requirements between calibration devices. The spacing between radar calibration devices should be no less than P1 pixels, and the spacing between optical calibration devices should be no less than P2 pixels. The physical scale of the calibration equipment interval is determined by combining the resolution of radar detection equipment and the resolution of optical detection equipment; the current position of the calibration equipment is compared with the field boundary. For particles that have not exceeded the field boundary, g2 is recorded as 0; for particles that have exceeded the field boundary, the Euclidean distance between the particle and the field boundary is used as the field boundary crossing scale, and the sum of the boundary crossing scales of all particles is used as g2.

8. The automated site calibration method for airborne radar and optical detection equipment according to claim 4, characterized in that: Imaging auxiliary data includes: the position and attitude of the detection device at the time of imaging; before the target detection and recognition unit identifies the position of the calibration device in the image, it filters the image to ensure that the image covers the calibration site; when the target detection and recognition unit identifies the position of the calibration device in the image, it uses the YOLOV5 algorithm to detect the calibration device, and further filters the detection results using the actual position of the calibration device to complete the identification and positioning of the calibration device in the aerial photograph.

9. The automated site calibration method for airborne radar and optical detection equipment according to claim 4, characterized in that: When determining the grayscale value Hi of the radiation power of each calibration device observed by the optical detection device in the grayscale space: the calibration processing module uses the local adaptive thresholding method to automatically extract the number of pixels and the grayscale value of each pixel of each calibration device in the optical image, and sums the pixels to obtain the total grayscale value observed by the optical detection device for the calibration device, which represents the grayscale value Hi of the radiation power of the calibration device observed by the optical detection device in the grayscale space.

10. The automated site calibration method for airborne radar and optical detection equipment according to claim 4, characterized in that: When determining the radiation / scattering physical quantity Ri of the apparent location of a radar detection device: based on the calibration mission parameters of the detection device and combined with the measured calibration device parameters, the radiation / scattering physical quantity Ri of the apparent location of the detection device is calculated using a transmission model.

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