Airborne radar installation error optimization method, electronic device and storage medium
Patent Information
- Application Number
- CN202511697424.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-19
- Publication Date
- 2026-11-03
AI Technical Summary
Existing methods for calibrating installation errors of airborne radar are costly, complex to operate, and lack dynamic error compensation capabilities, failing to accurately reflect the angle measurement performance under actual flight conditions.
By acquiring initial radar measurement data, inertial navigation data, and GPS ground truth data, interpolation and multi-coordinate system transformation are performed. By combining GPS ground truth and radar measurement data, the radar installation error is dynamically adjusted, and the radar installation attitude angle and position are optimized.
It improves the angle measurement accuracy of radar in actual flight conditions, reduces the requirements for measurement environment and equipment, adapts to the dynamic changes of aircraft in different attitudes, and improves measurement accuracy and applicability.
Smart Images
Figure CN123029477A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of radar target detection and tracking technology, and in particular to a method for optimizing airborne radar installation errors, electronic equipment, and storage medium. Background Technology
[0002] In the field of modern aviation technology, airborne radar, as a key detection device, has a crucial impact on radar performance, flight safety, and combat effectiveness. Traditionally, high-precision radar installation error measurement relies heavily on levels, such as coincidence levels. These require specialized calibration sites and the position and attitude of calibration plates. The accuracy of readings is improved by using bubble amplification in the level, and the sensitivity of the readings is adjusted using levers and fine-adjusting screws, so that radar measurement personnel can accurately measure, adjust, and calculate radar installation errors.
[0003] However, while this calibration method can meet the needs of radar installation error measurement and calibration to a certain extent, it mainly focuses on compensating for static errors and cannot effectively obtain the installation errors after actual coupling yaw, pitch and roll. This results in a certain deviation when calculating the radar angle measurement accuracy, making it difficult to accurately reflect the angle measurement performance of airborne radar in actual flight conditions.
[0004] Therefore, there is an urgent need for an airborne radar installation error optimization method with good dynamic error compensation capabilities to solve the above problems. Summary of the Invention
[0005] The purpose of this application is to provide a method for optimizing airborne radar installation errors, an electronic device, and a storage medium to solve the above-mentioned problems.
[0006] To achieve the above objectives, firstly, this application proposes a method for optimizing the installation error of airborne radar, the method comprising: Acquire initial radar measurement data, initial inertial navigation data, and initial GPS ground truth data for the preset processing interval; Interpolate the initial inertial navigation data and the initial GPS ground truth data to the track detection point time corresponding to the initial radar measurement data to obtain standard inertial navigation data and standard GPS ground truth data; The installation position coordinates and installation attitude angle of the antenna array are obtained. Based on the installation position coordinates, the installation attitude angle and the standard inertial navigation data, the initial radar measurement data is converted to the antenna array coordinate system to obtain the target radar measurement data. The standard GPS ground truth data is also converted from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data. The radar installation error is calculated based on the target radar measurement data and the target GPS true value data.
[0007] In some embodiments, the step of converting the initial radar measurement data to the antenna array coordinate system to obtain target radar measurement data further includes: The initial radar measurement data is transformed from the platform polar coordinate system to the platform rectangular coordinate system to obtain the first radar measurement data; Based on the installation attitude angle and the standard inertial navigation data, the first radar measurement data is transformed from the platform Cartesian coordinate system to the body Cartesian coordinate system to obtain the second radar measurement data; Based on the installation position coordinates of the antenna array and the installation attitude angle, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
[0008] The step of transforming the second radar measurement data from the aircraft's Cartesian coordinate system to the antenna array coordinate system based on the installation position coordinates of the antenna array and the installation attitude angle to obtain the target radar measurement data includes: Based on the installation position coordinates of the antenna array, calculate the offset of the second radar measurement data relative to the aircraft's Cartesian coordinate system. Based on the installation attitude angle, calculate the transformation rotation matrix for the second radar measurement data from the body rectangular coordinate system to the antenna array coordinate system; Based on the installation position offset and the transformation rotation matrix, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
[0009] In some implementations, the step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: The standard GPS true value data is transformed from the geographic coordinate system to the geocentric coordinate system to obtain the first GPS true value data; Based on the aircraft position coordinates corresponding to the standard inertial navigation data, the first GPS true value data is transformed from the geocentric coordinate system to the platform coordinate system to obtain the second GPS true value data; Based on the aircraft attitude corresponding to the standard inertial navigation data, the second GPS true value data is transformed from the platform coordinate system to the body coordinate system to obtain the third GPS true value data; Based on the installation location coordinates and the installation attitude angle, the third GPS ground truth data is transformed from the body coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data.
[0010] In some embodiments, after obtaining the mounting position coordinates and mounting attitude angle of the antenna array, the method further includes: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation attitude angle is iterated for a preset number of iterations according to a preset attitude angle iteration step size and a preset attitude angle iteration width. The step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: Based on the installation location coordinates, the iterated installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round. The step of calculating the radar installation error based on the target radar measurement data and the target GPS true value data includes: Based on the target radar measurement data and the target GPS true value data of the corresponding iteration round, the radar installation error of the corresponding iteration round is calculated.
[0011] In some embodiments, after calculating the radar installation error for the corresponding iteration based on the target radar measurement data and the target GPS ground truth data for the corresponding iteration, the method further includes: Detect whether there are any target iterations in the radar installation errors corresponding to each iteration round that meet the preset radar measurement accuracy threshold; If it does not exist, the preset attitude angle iteration width is increased, and the installation attitude angle is iterated for a preset number of iterations according to the installation position coordinates, the installation attitude angle and the standard inertial navigation data, based on the preset attitude angle iteration step size and the increased preset attitude angle iteration width. If it exists, then reduce the preset attitude angle iteration step size and the preset attitude angle iteration width, and select the installation attitude angle corresponding to the iteration round with the smallest radar installation error as the iteration attitude angle.
[0012] In some embodiments, after obtaining the mounting position coordinates and mounting attitude angle of the antenna array, the method further includes: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation position coordinates are iterated for a preset number of iterations according to a preset position iteration step size and a preset position iteration width. The step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: Based on the iterated installation location coordinates, the installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round. The step of calculating the radar installation error based on the target radar measurement data and the target GPS true value data includes: Based on the target radar measurement data and the target GPS true value data of the corresponding iteration round, the radar installation error of the corresponding iteration round is calculated.
[0013] In some implementations, acquiring radar measurement data, initial inertial navigation data, and initial GPS ground truth data within a preset processing interval includes: Determine the target flight zone based on the aircraft's flight trajectory; Acquire the original radar measurement data, initial inertial navigation data, and initial GPS ground truth data of the aircraft in the target flight zone; Radar measurement data within the preset processing interval are selected from the original radar measurement data. The preset processing interval includes the period from point aggregation to before track filtering.
[0014] Compared with the prior art, the beneficial effects of this application include: Firstly, compared to traditional radar installation error measurement methods limited to static error compensation, this application unifies data from different coordinate systems into the antenna array coordinate system through data interpolation and coordinate system transformation. By combining GPS ground truth with radar measurement data for error analysis, it can more comprehensively and accurately reflect the radar's angle measurement performance under actual flight conditions, thus improving measurement accuracy. Secondly, in actual flight, the aircraft's attitude is constantly changing. The method in this application can dynamically adjust and optimize the radar's installation error under different flight attitudes, adapting to the dynamic changes of aircraft or other flight platforms in actual flight and ensuring high accuracy in radar measurements. Thirdly, compared to traditional radar installation error measurement methods that rely on equipment such as levels and require specialized calibration sites and calibration plate positions and attitudes, this application reduces the requirements for the measurement environment and equipment, allowing for implementation in more flexible scenarios and improving applicability. Attached Figure Description
[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope of this application.
[0016] Figure 1 This is a flowchart illustrating an airborne radar installation error optimization method in one embodiment; Figure 2 This is a flowchart illustrating the airborne radar installation error optimization method in another embodiment; Figure 3This is a schematic diagram illustrating the detailed process of converting the initial radar measurement data to the antenna array coordinate system to obtain the target radar measurement data in one embodiment. Figure 4 This is a schematic diagram of the overall data flow of an airborne radar installation error optimization method in one embodiment; Figure 5 This is a schematic diagram illustrating the detailed process of converting the initial radar measurement data to the antenna array coordinate system to obtain the target radar measurement data in another embodiment. Figure 6 This is a schematic diagram of the process of converting the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data in one embodiment. Figure 7 This is a detailed flowchart illustrating the iteration of the installation attitude angle in one embodiment; Figure 8 This is a detailed flowchart illustrating the iteration process for the installation location coordinates in one embodiment; Figure 9 This is a schematic diagram of the electronic equipment involved in the airborne radar installation error optimization method in the embodiments of this application. Detailed Implementation
[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0018] All terms used in this application (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.
[0019] For example, the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For instance, without departing from the scope of this application, first radar measurement data may be referred to as second radar measurement data, and similarly, second radar measurement data may be referred to as first radar measurement data. Both first radar measurement data and second radar measurement data are radar measurement data, but they are not the same radar measurement data.
[0020] For example, the terms "comprising" or "including" used in this application indicate the presence of features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.
[0021] As mentioned earlier, in the field of modern aviation technology, airborne radar, as a critical detection device, has a crucial impact on radar performance, flight safety, and combat effectiveness. Even minor deviations in the installation of the airborne radar antenna array, such as slight variations in yaw, pitch, and roll angles, can lead to errors in the radar's measurement of target position and velocity, thus affecting the aircraft's navigation, target tracking, and attack accuracy. Therefore, accurately measuring and calibrating the installation errors of airborne radar is a core aspect of ensuring the performance of airborne radar systems.
[0022] Traditionally, high-precision radar installation error measurement relies heavily on levels, such as coincidence levels. These levels improve reading accuracy by using a bubble amplification in the level and adjust reading sensitivity using levers and fine-adjusting screws, allowing radar surveyors to accurately measure, adjust, and calculate radar installation errors. In contrast, airborne radar array installation error calibration typically utilizes high-precision calibration plates, turntables, and measuring instruments. During operation, skilled technicians must precisely control the measuring instruments and perform complex analyses and calculations on the collected data to determine the installation errors of the radar array.
[0023] However, current methods for calibrating airborne radar array installation errors have several significant problems. Firstly, calibration equipment is expensive; high-precision calibration boards, turntables, and measuring instruments are costly, increasing the economic cost of calibrating airborne radar installation errors. Secondly, the operation is highly complex, typically requiring experienced technicians with extensive knowledge to skillfully operate complex measuring instruments and analyze large amounts of data. This limits the widespread and rapid implementation of calibration work and can easily affect the accuracy of calibration results due to differences in operator skill levels. Furthermore, the most critical issue is the insufficient dynamic error compensation capability of existing calibration methods. They primarily focus on compensating for static errors and cannot effectively acquire the installation errors after actual coupling of yaw, pitch, and roll. This leads to certain deviations in calculating radar angle measurement accuracy, making it difficult to accurately reflect the angle measurement performance of airborne radar under actual flight conditions. In reality, when determining the rotation matrix of the airborne radar array system to the northeast-northeast coordinate system centered on the aircraft, the installation errors of the array radar are mutually coupled and cannot be simply obtained by directly measuring the yaw, pitch, and roll angles of the radar array relative to the nose of the aircraft. This makes it difficult for existing calibration methods to meet the high-precision installation error calibration requirements of modern airborne radar.
[0024] Therefore, there is an urgent need for an airborne radar installation error optimization method with good dynamic error compensation capabilities to solve the above problems. To this end, this application proposes an airborne radar installation error optimization method, electronic equipment, and storage medium, which can improve the measurement accuracy of airborne radar installation errors.
[0025] In one embodiment, such as Figure 1 As shown in the figure, this application proposes a method for optimizing the installation error of airborne radar, which includes the following steps: Step S10: Obtain radar measurement data, initial inertial navigation data, and initial GPS ground truth data for the preset processing interval.
[0026] In this embodiment, the preset processing interval is used to filter radar measurement data that is in the preset processing stage. For example, the preset processing interval or preset processing stage may include the period from after point convergence to before track filtering, thereby avoiding non-measurement errors caused by different filtering methods. Initial inertial navigation data refers to the aircraft motion data provided by the aircraft's inertial navigation system, including timestamps and aircraft longitude (…). ),latitude( ),high( ) and attitude angles (yaw angle) Pitch angle Roll angle Initial GPS ground truth data refers to the aircraft's location information provided by GPS (Global Positioning System), including timestamps and longitude. ),latitude( ) and height ( ).
[0027] In some implementations, such as Figure 2 As shown, step S10 includes: Step S11: Determine the target flight zone based on the aircraft's flight trajectory.
[0028] In this embodiment, the aircraft flight trajectory refers to the flight path of the aircraft during the execution of the mission, including information such as position, speed, and time. The target flight interval refers to a specific time period or flight phase within the flight trajectory selected according to measurement requirements. For example, to improve the accuracy and reliability of error measurement, a relatively stable flight phase can be selected as the target flight interval. The target flight interval may include the aircraft's level flight phase or the target's straight flight phase, where the target refers to the object being tracked or detected by the aircraft.
[0029] Step S12: Obtain the original radar measurement data, initial inertial navigation data, and initial GPS ground truth data of the aircraft in the target flight zone.
[0030] In this embodiment, raw radar measurement data refers to the radar measurement data originally detected by the airborne radar within the target flight zone, containing a large number of detection points and potentially including noise and outliers. Initial inertial navigation data refers to the aircraft motion data recorded by the aircraft's inertial navigation system within the target flight zone, including timestamps and aircraft longitude (…). ),latitude( ),high( ) and attitude angles (yaw angle) Pitch angle Roll angle Initial GPS ground truth data refers to the aircraft position information provided by GPS within the target flight zone, including timestamp, longitude (gLon), latitude (gLat), and altitude (gAlt).
[0031] Step S13: Select initial radar measurement data that falls within the preset processing range from the original radar measurement data.
[0032] In this embodiment, the preset processing interval refers to the data processing stage from after point aggregation processing to before track filtering processing. Point aggregation is the process of fusing multiple radar detection points in the original radar measurement data into more accurate track points, while track filtering is the process of smoothing the target track and removing noise and outliers.
[0033] Specifically, the raw radar measurement data can be processed by first performing point aggregation to merge multiple detection points into more accurate track points, and then filtering out the required initial radar measurement data before track filtering to ensure that the data has undergone preliminary processing but has not been affected by filtering, thus retaining more original features.
[0034] This implementation method improves the accuracy of error analysis and avoids the influence of errors introduced by filtering algorithms on measurement results by selecting initial radar measurement data that has undergone preliminary processing but has not been affected by filtering.
[0035] Step S20: Interpolate the initial inertial navigation data and the initial GPS ground truth data to the track detection point time corresponding to the initial radar measurement data to obtain standard inertial navigation data and standard GPS ground truth data.
[0036] In this embodiment, the track detection point time refers to the specific time point at which the airborne radar detects the target and records the track data. Since the sampling frequencies of the airborne radar, airborne inertial navigation system, and GPS may be different, interpolation algorithms (such as linear interpolation or spline interpolation) can be used to align the time points of the initial inertial navigation data and the initial GPS ground truth data to the radar track detection point time.
[0037] In some implementations, the initial inertial navigation data is matched and interpolated with the track detection point time to obtain the standard inertial navigation data at the track detection point time. (Units are in the following order: s, rad, rad, m, rad, rad, rad). The initial GPS ground truth data is matched and interpolated with the track detection point times to obtain the standard GPS ground truth values for the track detection point times. (Units are in the following order: s, rad, rad, m).
[0038] Step S30: Obtain the installation position coordinates and installation attitude angle of the antenna array, and based on the installation position coordinates, the installation attitude angle and the standard inertial navigation data, convert the initial radar measurement data to the antenna array coordinate system to obtain the target radar measurement data, and convert the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data.
[0039] In this embodiment, the installation position coordinates of the antenna array refer to the position of the antenna array on the aircraft platform, usually represented by coordinate values in the platform coordinate system. The installation attitude angles, including at least one of yaw, pitch, and roll angles, are used to describe the installation direction of the antenna array on the aircraft platform. The platform coordinate system is a northeast-sky coordinate system centered on the aircraft platform, with the aircraft's center of mass as the origin, the X-axis pointing due east, the Y-axis pointing due north, and the Z-axis determined by the right-hand rule. The antenna array coordinate system has the antenna phase center as the origin, the X-axis as the major axis of the antenna array (pointing towards the nose), the Z-axis as the antenna array normal (positive in the radiation direction), and the Y-axis as the minor axis of the antenna array, determined by the right-hand rule. The geographic coordinate system is also called the WGS84 coordinate system and the latitude, longitude, and altitude (longitude, latitude, and altitude) coordinate system.
[0040] In some implementations, the initial radar measurement data is represented in the platform's polar coordinate system, such as... Figure 3 and Figure 4 As shown, step S30, which involves converting the initial radar measurement data to the antenna array coordinate system to obtain the target radar measurement data, includes: Step S31: Convert the initial radar measurement data from the platform polar coordinate system to the platform rectangular coordinate system to obtain the first radar measurement data.
[0041] Specifically, the initial radar measurement data is represented in the platform's polar coordinate system as follows: ,in, It is the straight-line distance between the target and the airborne radar. It's the azimuth. It is the elevation angle. The first radar measurement data is its coordinates transformed to the platform's rectangular coordinate system. ,in Let be the position vector of the target in the platform's rectangular coordinate system. Its specific calculation process is shown in formula (1): (1) Step S32: Based on the installation attitude angle and the standard inertial navigation data, the first radar measurement data is converted from the platform Cartesian coordinate system to the body Cartesian coordinate system to obtain the second radar measurement data.
[0042] In this embodiment, the installation attitude angle Including yaw angle Pitch angle Roll angle According to the installation attitude angle The rotation matrix for each track point to transform from the antenna array coordinate system to the aircraft's Cartesian coordinate system. As shown in calculation formula (2): (2) Inertial attitude angles in standard inertial navigation data include Based on the inertial attitude angle, the rotation matrix for each track point to transform from the aircraft Cartesian coordinate system to the platform Cartesian coordinate system. Simply change the yaw angle in formula (2) Pitch angle Roll angle Replace them with the corresponding times. , and The value is sufficient and will not be elaborated upon here.
[0043] Based on the above calculation formulas (1) and (2), the second radar measurement data are the coordinates of the track points at different times in the aircraft's rectangular coordinate system. The coordinates of the target at each waypoint in the aircraft's Cartesian coordinate system ,in, It refers to the inverse matrix of the rotation matrix from the platform Cartesian coordinate system to the body Cartesian coordinate system.
[0044] Step S33: Based on the installation position coordinates of the antenna array and the installation attitude angle, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
[0045] In this embodiment, the antenna array coordinate system can be divided into an antenna array rectangular coordinate system and an antenna array polar coordinate system. The target radar measurement data consists of the coordinates of the track points at different times in the antenna array polar coordinate system. In some implementations, the installation location coordinates of the antenna array are used. Calculate the coordinates of the track points at different times in the Cartesian coordinate system of the antenna array. The coordinates of the target at each track point in the Cartesian coordinate system of the array. Specifically, as shown in calculation formula (3): (3) in, It refers to the inverse matrix of the rotation matrix that transforms from the antenna array coordinate system to the body rectangular coordinate system, that is, the transformation rotation matrix from the body rectangular coordinate system to the antenna array coordinate system. This refers to the coordinates of the target in the Cartesian coordinate system of the machine. It refers to the installation position coordinates of the antenna array in the Cartesian coordinate system of the aircraft.
[0046] Furthermore, Target radar measurement data obtained by converting to the array polar coordinate system As shown in the calculation formula (4): (4) in, Let the distance of the target in the polar coordinate system of the array be denoted as . Let be the azimuth angle of the target in the polar coordinate system of the array. Let the target be the elevation angle in the polar coordinate system of the array. , and Let be the coordinates of the target in the rectangular coordinate system of the antenna array. By calculating formula (4), the coordinates in the rectangular coordinate system of the antenna array are further converted into the coordinates in the polar coordinate system of the array, which can facilitate the radar system to represent and process the target in polar coordinates, and is more in line with the measurement method and data representation habits of airborne radar.
[0047] In some implementations, such as Figure 5 As shown, step S33 includes: Step S331: Calculate the offset of the second radar measurement data relative to the aircraft's rectangular coordinate system based on the installation position coordinates of the antenna array.
[0048] In this embodiment, the coordinates of each track point in the second radar measurement data in the aircraft's Cartesian coordinate system are... Subtract the installation coordinates of the antenna array This gives the installation position offset.
[0049] Step S332: Based on the installation attitude angle, calculate the transformation rotation matrix for converting the second radar measurement data from the body rectangular coordinate system to the antenna array coordinate system.
[0050] In this embodiment, the transformation rotation matrix refers to... .
[0051] Step S333: Based on the installation position offset and the transformation rotation matrix, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
[0052] The specific conversion process is described in step S33, and will not be elaborated further in this embodiment.
[0053] It should be noted that representing the initial radar measurement data in the platform polar coordinate system does not constitute a limitation on the embodiments of this application, but is only one implementation method of the embodiments of this application. Regardless of the coordinate system in which the initial actual radar measurement data is represented, it is only necessary to ensure that it is eventually transformed to the antenna array polar coordinate system.
[0054] In some implementations, such as Figure 4 and Figure 6 As shown, step S30, which involves transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data, includes: Step S34: Convert the standard GPS true value data from the geographic coordinate system to the geocentric coordinate system to obtain the first GPS true value data.
[0055] In this embodiment, the Earth-centered Earth-fixed coordinate system (ECEF) refers to a coordinate system with the Earth's center as the origin, the coordinate axes fixed to the Earth, the X-axis pointing to the intersection of the prime meridian and the equator, the Y-axis perpendicular to the X-axis and located at the equatorial plane, and the Z-axis pointing to the Earth's North Pole.
[0056] Standard GPS true data First GPS ground truth data converted to Earth-centered Earth-fixed coordinate system As shown in the calculation formula (5): (5) Where a is the length of the Earth's semi-axial length, b is the length of the Earth's minor semi-axial length, and e is the square of the Earth's first eccentricity. .
[0057] Step S35: Based on the aircraft position coordinates corresponding to the standard inertial navigation data, the first GPS ground truth data is transformed from the geocentric coordinate system to the platform coordinate system to obtain the second GPS ground truth data.
[0058] In this embodiment, for the standard GPS true value data at different times, the calculation formula (5) is replaced sequentially. for The corresponding aircraft position coordinates based on the geocentric-ground-fixed coordinate system at that time were obtained. Further, second GPS ground truth data based on the platform coordinate system was obtained. The calculation process is shown in formula (6): (6) Step S36: Based on the aircraft attitude in the standard inertial navigation data, the second GPS ground truth data is transformed from the platform coordinate system to the body coordinate system to obtain the third GPS ground truth data.
[0059] In this embodiment, the aircraft attitude refers to the inertial navigation attitude angle in the standard inertial navigation data. This is based on the third GPS ground truth data at different times. The second GPS ground truth data is transformed from the platform coordinate system to the body coordinate system to obtain... ,in, ( The yaw angle is calculated from formula (2). Pitch angle Roll angle Replace them with the standard inertial navigation data at the corresponding time points. , and (The value is sufficient).
[0060] Step S37: Based on the installation position coordinates and the installation attitude angle, the third GPS true value data is transformed from the body coordinate system to the antenna array coordinate system to obtain the target GPS true value data.
[0061] In this embodiment, the installation position coordinates of the antenna array are used. Calculate the true GPS data of the target at different times. .in, The specific calculation process is shown in calculation formula (7): (7) in, This is the inverse of the rotation matrix from the antenna array coordinate system to the body coordinate system. The specific calculation process is not detailed here; please refer to [reference needed]. The calculation process.
[0062] Step S40: Calculate the radar installation error based on the target radar measurement data and the target GPS true value data.
[0063] Radar installation error refers to the deviation between the actual installation position and attitude of the radar and the ideal state, which affects the accuracy of target measurement. In the antenna array coordinate system, the target radar measurement data is compared with the target GPS true data, and the difference between the two is calculated. Statistical methods (such as mean and standard deviation) are used to calculate the radar installation error. For example, radar installation error can include the standard deviation, root mean square, and mean error of the range, azimuth, and elevation angles in the array system.
[0064] The airborne radar installation error optimization method proposed in this application has three main aspects. First, compared to traditional radar installation error measurement methods limited to static error compensation, this application unifies data from different coordinate systems to the antenna array coordinate system through data interpolation and coordinate system transformation. By combining GPS ground truth with radar measurement data for error analysis, it can more comprehensively and accurately reflect the radar's angle measurement performance under actual flight conditions, thus improving measurement accuracy. Second, in actual flight, the aircraft's attitude is constantly changing. The method in this application can dynamically adjust and optimize the radar installation error under different flight attitudes, adapting to the dynamic changes of aircraft or other flight platforms in actual flight and ensuring high accuracy in radar measurements. Third, compared to traditional radar installation error measurement methods that rely on equipment such as levels and require specialized calibration sites and calibration plate positions and attitudes, this application reduces the requirements for the measurement environment and equipment, allowing for implementation in more flexible scenarios and improving applicability.
[0065] In one embodiment, such as Figure 7 As shown, in step S30, after obtaining the installation position coordinates and installation attitude angle of the antenna array, the following is also included: Step S301: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation attitude angle is iterated for a preset number of iterations according to a preset attitude angle iteration step size and a preset attitude angle iteration width.
[0066] In this embodiment, the preset attitude angle iteration step size refers to the adjustment range of the installed attitude angle in each iteration. The preset attitude angle iteration width refers to the adjustment range of the installed attitude angle.
[0067] To avoid excessively long calculation times and to prevent large errors compared to the original installation attitude angle measurement, a large preset attitude angle iteration step size is defined first. Preset attitude angle iteration width Therefore, the iterative range of the antenna array's mounting attitude angle is: .
[0068] Step S302: Based on the installation location coordinates, the iterated installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round.
[0069] In this embodiment, the number is recorded as... The iterative value of the secondary antenna array attitude angle is... Referring to step S32, calculate the yaw angle in formula (2). Pitch angle Roll angle Replace them with the corresponding iteration rounds. , and By calculating the value, we can obtain the rotation matrix from the antenna array coordinate system to the body coordinate system.
[0070] Similarly, the first In the next iteration, referring to step S37, the target GPS true value data in the array plane rectangular coordinate system is... Convert to the polar coordinate system of the array surface Specifically, as shown in calculation formula (8): (8) The remaining steps are described in the above embodiments and implementation methods, and will not be elaborated further here.
[0071] Based on this embodiment, S40 further includes: Step S401: Calculate the radar installation error for the corresponding iteration based on the target radar measurement data and the target GPS ground truth data for the corresponding iteration.
[0072] In this embodiment, the calculation of the first step is based on steps S301 and S302. Radar installation error during the next iteration (Units: m, deg, deg). After removing outliers based on the 3-σ criterion, the measurement error of this batch of track points is obtained. At the same time, the standard deviation, root mean square, and mean of the corresponding errors (array system distance, azimuth angle, elevation angle) are calculated.
[0073] In some embodiments, the method further includes the following after step S401: The system checks whether there is a target iteration cycle in the radar installation error corresponding to each iteration cycle that meets the preset radar measurement accuracy threshold. If not, the preset attitude angle iteration width is increased, and the installation attitude angle is iterated for a preset number of iteration cycles according to the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, using the preset attitude angle iteration step size and the increased preset attitude angle iteration width. Step S302 is then repeated. If a target iteration cycle with the smallest radar installation error is found, the preset attitude angle iteration step size and the preset attitude angle iteration width are reduced, and the installation attitude angle corresponding to the target iteration cycle with the smallest radar installation error is selected as the iterated attitude angle.
[0074] In some implementations, other measurement data containing GPS true values can also be used to select the attitude angle. Verify whether the radar installation error meets the radar measurement accuracy threshold; if so, the requirement is met; otherwise, repeat step S301.
[0075] Furthermore, the threshold values for radar measurement accuracy are not limited to the standard deviation, root mean square, and mean error of the range, azimuth, and elevation angle errors of the array system; they can be determined based on actual radar accuracy assessment indicators. Simultaneously, the mean error can be used to measure whether the preset attitude angle iteration width is appropriate.
[0076] In the airborne radar installation error optimization method proposed in the embodiments of this application, such as Figure 4 As shown, this application first performs time registration between the acquired initial inertial navigation data and initial GPS ground truth data and the track detection point time of the initial radar measurement data. Then, using the time-registered standard inertial navigation data and the initial installation position coordinates and installation attitude angles of the antenna array, a series of coordinate transformations are performed to convert the initial radar measurement data to the polar coordinate system of the antenna array. Simultaneously, using the time-registered standard inertial navigation data and the installation position and installation attitude angles of the antenna array, the installation attitude angles are iterated to convert the standard GPS ground truth data to the polar coordinate system of the antenna array. Error analysis is then performed on the obtained target radar measurement data and the target GPS ground truth data for the corresponding iteration rounds. Furthermore, by iterating through multiple rounds with a preset attitude angle iteration step size and preset attitude angle iteration width, a radar measurement accuracy threshold is reached. This application does not rely on precise initial antenna array measurements; it uses offline data to iteratively optimize the antenna array's installation attitude angles through multiple rounds of threshold scaling. Simultaneously, it can utilize multiple batches of measurement data containing GPS ground truth for verification and optimization. The algorithm complexity is low, making it convenient for engineering practice.
[0077] In one embodiment, such as Figure 8 As shown, in step S30, after obtaining the installation position coordinates and installation attitude angle of the antenna array, the following is also included: Step S303: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation position coordinates are iterated for a preset number of iterations according to a preset position iteration step size and a preset position iteration width.
[0078] In this embodiment, the preset position iteration step size refers to the adjustment range of the installation position coordinates in each iteration. The preset position iteration width refers to the adjustment range of the installation position coordinates. Iterations are performed using the initial installation position coordinates as the center, according to the preset step size and width.
[0079] Step S304: Based on the iterated installation location coordinates, the installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round.
[0080] Based on this embodiment, S40 further includes: Step S401: Calculate the radar installation error for the corresponding iteration based on the target radar measurement data and the target GPS ground truth data for the corresponding iteration.
[0081] It should be noted that the embodiments corresponding to steps S301 and S302, and the embodiment corresponding to steps S303 and S304, can be applied individually or in combination. The specific execution process of the embodiment corresponding to steps S303 and S304 can be referred to the above embodiments and implementation methods, and the calculation can be performed based on the iterated installation position coordinates. This application will not elaborate further on this.
[0082] The airborne radar installation error optimization method proposed in this application does not rely on the original measurement values of the radar antenna array. It can optimize the installation attitude error of the antenna array through multiple batches of offline data iteration and data verification. It can also be used to optimize the installation position error of the antenna array.
[0083] In one embodiment, a computer-readable storage medium is provided having executable instructions stored thereon, which, when executed by a processor, cause the processor to perform the steps in the above method embodiments.
[0084] In one embodiment, an electronic device is also provided, including one or more processors; and a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors perform the steps in the above method embodiments.
[0085] In one embodiment, such as Figure 9 The diagram illustrates the structure of an electronic device used to implement an embodiment of this application. The electronic device 900 includes a central processing unit (CPU) 901, which can perform various appropriate actions and processes based on a program stored in a read-only memory (ROM) 902 or a program loaded from a storage portion 908 into a random access memory (RAM) 903. The RAM 903 also stores various programs and data required for the operation of the electronic device 900. The CPU 901, ROM 902, and RAM 903 are interconnected via a bus 904. An input / output (I / O) interface 905 is also connected to the bus 904.
[0086] The following components are connected to I / O interface 905: an input section 906 including a keyboard, mouse, etc.; an output section 907 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 908 including a hard disk, etc.; and a communication section 909 including a network interface card such as a LAN card, modem, etc. The communication section 909 performs communication processing via a network such as the Internet. A drive 910 is also connected to I / O interface 905 as needed. A removable medium 911, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 910 as needed so that computer programs read from it can be installed into storage section 908 as needed.
[0087] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer-readable medium carrying instructions that, in such embodiments, can be downloaded and installed from a network via a communication section 909, and / or installed from a removable medium 911. When the instructions are executed by a central processing unit (CPU) 901, the various method steps described in this application are performed.
[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions carried out in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
[0089] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the embodiments claimed above can be used in any combination. The information disclosed in this background section is intended only to enhance the understanding of the general background of this application and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.
Claims
1. A method for optimizing the installation error of airborne radar, characterized in that, The method includes: Acquire initial radar measurement data, initial inertial navigation data, and initial GPS ground truth data for the preset processing interval; Interpolate the initial inertial navigation data and the initial GPS ground truth data to the track detection point time corresponding to the initial radar measurement data to obtain standard inertial navigation data and standard GPS ground truth data; The installation position coordinates and installation attitude angle of the antenna array are obtained. Based on the installation position coordinates, the installation attitude angle and the standard inertial navigation data, the initial radar measurement data is converted to the antenna array coordinate system to obtain the target radar measurement data. The standard GPS ground truth data is also converted from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data. The radar installation error is calculated based on the target radar measurement data and the target GPS true value data.
2. The airborne radar installation error optimization method according to claim 1, characterized in that, The step of converting the initial radar measurement data to the antenna array coordinate system to obtain the target radar measurement data further includes: The initial radar measurement data is transformed from the platform polar coordinate system to the platform rectangular coordinate system to obtain the first radar measurement data; Based on the installation attitude angle and the standard inertial navigation data, the first radar measurement data is transformed from the platform Cartesian coordinate system to the body Cartesian coordinate system to obtain the second radar measurement data; Based on the installation position coordinates of the antenna array and the installation attitude angle, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
3. The airborne radar installation error optimization method according to claim 2, characterized in that, The step of transforming the second radar measurement data from the aircraft's Cartesian coordinate system to the antenna array coordinate system based on the installation position coordinates of the antenna array and the installation attitude angle to obtain the target radar measurement data includes: Based on the installation position coordinates of the antenna array, calculate the offset of the second radar measurement data relative to the aircraft's Cartesian coordinate system. Based on the installation attitude angle, calculate the transformation rotation matrix for the second radar measurement data from the body rectangular coordinate system to the antenna array coordinate system; Based on the installation position offset and the transformation rotation matrix, the second radar measurement data is transformed from the body rectangular coordinate system to the antenna array coordinate system to obtain the target radar measurement data.
4. The airborne radar installation error optimization method according to claim 1, characterized in that, The step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: The standard GPS true value data is transformed from the geographic coordinate system to the geocentric coordinate system to obtain the first GPS true value data; Based on the aircraft position coordinates corresponding to the standard inertial navigation data, the first GPS true value data is transformed from the geocentric coordinate system to the platform coordinate system to obtain the second GPS true value data. Based on the aircraft attitude corresponding to the standard inertial navigation data, the second GPS true value data is transformed from the platform coordinate system to the body coordinate system to obtain the third GPS true value data; Based on the installation location coordinates and the installation attitude angle, the third GPS ground truth data is transformed from the body coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data.
5. The airborne radar installation error optimization method according to claim 1, characterized in that, After obtaining the installation position coordinates and installation attitude angle of the antenna array, the method further includes: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation attitude angle is iterated for a preset number of iterations according to a preset attitude angle iteration step size and a preset attitude angle iteration width. The step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: Based on the installation location coordinates, the iterated installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round. The step of calculating the radar installation error based on the target radar measurement data and the target GPS true value data includes: Based on the target radar measurement data and the target GPS true value data of the corresponding iteration round, the radar installation error of the corresponding iteration round is calculated.
6. The airborne radar installation error optimization method according to claim 5, characterized in that, After calculating the radar installation error for the corresponding iteration based on the target radar measurement data and the target GPS ground truth data for the corresponding iteration, the method further includes: Detect whether there are target iterations in each iteration round whose radar installation errors meet the preset radar measurement accuracy threshold. If it does not exist, the preset attitude angle iteration width is increased, and the installation attitude angle is iterated for a preset number of iterations according to the installation position coordinates, the installation attitude angle and the standard inertial navigation data, based on the preset attitude angle iteration step size and the increased preset attitude angle iteration width. If it exists, then reduce the preset attitude angle iteration step size and the preset attitude angle iteration width, and select the installation attitude angle corresponding to the iteration round with the smallest radar installation error as the iteration attitude angle.
7. The airborne radar installation error optimization method according to claim 1, characterized in that, After obtaining the installation position coordinates and installation attitude angle of the antenna array, the method further includes: Based on the installation position coordinates, the installation attitude angle, and the standard inertial navigation data, the installation position coordinates are iterated for a preset number of iterations according to a preset position iteration step size and a preset position iteration width. The step of transforming the standard GPS ground truth data from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data includes: Based on the iterated installation location coordinates, the installation attitude angle, and the standard inertial navigation data, the standard GPS ground truth data is transformed from the geographic coordinate system to the antenna array coordinate system to obtain the target GPS ground truth data for the corresponding iteration round. The step of calculating the radar installation error based on the target radar measurement data and the target GPS true value data includes: Based on the target radar measurement data and the target GPS true value data of the corresponding iteration round, the radar installation error of the corresponding iteration round is calculated.
8. The airborne radar installation error optimization method according to claim 1, characterized in that, The acquisition of radar measurement data, initial inertial navigation data, and initial GPS ground truth data within a preset processing interval includes: Determine the target flight zone based on the aircraft's flight trajectory; Acquire the original radar measurement data, initial inertial navigation data, and initial GPS ground truth data of the aircraft in the target flight zone; Radar measurement data within the preset processing interval are selected from the original radar measurement data. The preset processing interval includes the period from point aggregation to before track filtering.
9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors perform the airborne radar installation error optimization method as described in any one of claims 1 to 8.
10. A computer storage medium, characterized in that, The storage medium stores executable instructions, which, when executed by a processor, cause the processor to perform the airborne radar installation error optimization method as described in any one of claims 1 to 8.