A method for calibrating an amphibious aircraft phased array weather radar installation

Abstract

The present invention provides a method for calibrating an amphibious aircraft phased array weather radar installation, comprising installing a calibration tool and a laser calibration target scope; tracking N horizontal measurement points on the aircraft fuselage using a laser tracking system to create a current aircraft-wide coordinate system on a ground target station; calibrating the theoretical coordinate position of the calibration scope laser emission point in the aircraft-wide coordinate system based on the aircraft body and the calibration tool digital model; correcting the cursor position; calibrating the target scope aiming position and inputting the calibration result; turning on the calibration target scope laser, calibrating the target scope aiming position on the cursor plane, recording data obtained during the calibration process, and inputting the calculated calibration result into a radar computer to complete the entire calibration process. The present invention can solve the problem of high labor, material, and time costs during the ground calibration process of airborne phased array weather radars after installation. It can also solve the problem of difficulty in calibrating amphibious aircraft radars after later installation in non-open flat environments.

Description

Technical Field

[0001] The invention relates to the technical field of calibration and correction of amphibious aircraft, and in particular to an installation and calibration method of a phased array weather radar of an amphibious aircraft. Background Art

[0002] With the widespread application and rapid development of phased array technology in radar, communications, and other fields, the active phased array weather radars carried by certain amphibious aircraft have demonstrated outstanding advantages in anti-interference capabilities, detection accuracy, and functional diversity. Furthermore, compared to traditional radars that mechanically rotate the radar antenna, phased array radars arrange multiple radiating elements on a planar antenna, using computers to control the current of the radiating elements to change the beam direction for scanning. This enables long-range, multi-target scanning detection with high sensitivity and precision. This places higher demands on the accuracy of the calibration of phased array weather radar system errors.

[0003] Airborne weather radars require ground calibration after installation. Calibration primarily focuses on the flatness of the radar antenna base and the mounting surface, as well as the parallelism of the entire active phased array antenna to the mounting surface, its perpendicularity to the pitch axis, and its perpendicularity to the horizontal plane. Traditional radar calibration methods primarily use antenna array telescopes and cursor pads to measure the horizontal (vertical) deviation between the antenna optical axis and the antenna mechanical axis. This testing method makes it easier to calibrate ground-based radars by finding the verticality and horizontality of the radar turntable and the cursor pad bracket, thereby adjusting the angles of the antenna and cursor pad to make them parallel. After the airborne weather radar is installed, the aircraft body serves as the turntable, and leveling the body is a labor-intensive task. Manually leveling the body requires a significant investment of manpower and material resources, consumes a significant amount of time, and the verticality of the cursor pad bracket is difficult to guarantee, impacting the measurement accuracy and results of the calibration equipment. Summary of the Invention

[0004] The purpose of the present invention is to address the shortcomings of the above-mentioned traditional radar calibration method and provide a method for installing and calibrating a phased array weather radar for amphibious aircraft. The method can solve the problem of high manpower, material and time costs during the ground calibration process of airborne phased array weather radar after installation. At the same time, it can also solve the problem of difficulty in calibrating the radar after amphibious aircraft are replaced in a non-open flat environment in the later stage.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A method for calibrating an amphibious aircraft phased array weather radar installation comprises the following steps:

[0007] Install calibration fixture and laser calibration target mirror;

[0008] The laser tracking system is used to track N horizontal measurement points on the aircraft fuselage, and the current aircraft coordinate system is created on the ground target station;

[0009] In the whole aircraft coordinate system, the theoretical coordinate position of the laser emission point of the calibration mirror is calibrated based on the digital model of the aircraft body and the calibration fixture;

[0010] Correcting the cursor plate position, including: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor plate plane;

[0011] Calibrate the aiming position of the target scope and input the calibration results. Turn on the laser calibration scope and calibrate the aiming position of the laser calibration scope on the cursor plate plane. Record the data obtained during the calibration process and input the calculated calibration results into the radar computer to complete the entire calibration process.

[0012] According to the present invention, a method for installing and calibrating an amphibious aircraft phased array weather radar, the installation and calibration tooling and the laser calibration scope include:

[0013] Install the calibration tool vertically above the weather radar, and install the laser calibration scope offset on the top of the antenna, with its azimuth consistent with the direction of the aircraft body to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft;

[0014] The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

[0015] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation, wherein tracking N horizontal measurement points on the aircraft fuselage by a laser tracking system comprises:

[0016] Ten horizontal measurement points on the aircraft fuselage are selected as the target point distribution points for establishing the coordinate system, including four horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there are six horizontal measurement points on the aircraft fuselage, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail.

[0017] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation, the method of creating a current aircraft full-machine coordinate system in a ground target station includes:

[0018] Use the ground target station software platform to establish the full aircraft coordinate system:

[0019] Establish a horizontal plane based on 3 left, 3 right and 4 left points;

[0020] The symmetry plane of the whole aircraft is established based on the midpoints of 1 left and 2 right and the midpoints of 2 left and 2 right;

[0021] The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

[0022] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation, the method of calibrating the theoretical coordinate position of the emission point of the laser calibration scope includes:

[0023] According to the digital-analog connection relationship between the laser calibration scope and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emission point of the laser calibration scope is calibrated according to the origin (0, 0, 0) of the global coordinate system established by the target station software platform, and the pitch offset distance Dz of the target scope is obtained. This distance represents the offset of the laser emission point in the vertical direction relative to the origin of the global coordinate system.

[0024] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation, the calibration of the cursor position includes:

[0025] Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system;

[0026] Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line;

[0027] Based on the tracked coordinates, the offset of the cursor plate relative to the global coordinate system is calculated to correct the cursor plate position so that the cursor plate is at the position required by the radar calibration distance, that is, the origin of the cursor plate coincides with the origin of the global coordinate system;

[0028] Adjust the plane of the cursor board so that the aircraft axis on the cursor board coincides with the axis of the aircraft body, and adjust the position and posture of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body;

[0029] Make sure the cursor pad plane is parallel to the antenna radiating surface.

[0030] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation is provided. When placing a spherical reflector, four fixed adjustment points on a cursor plate are designated as fixed positions of the spherical reflector, which are located at the origin, the horizontal line, and the vertical line, and are designated as the origin O, point A, point B, and point C.

[0031] A laser tracking system is used to track the coordinates of the origin O and the spherical reflectors at points A, B, and C on the cursor board. During the adjustment of the cursor board plane, the coordinate data of the target station software platform is monitored in real time.

[0032] According to the installation calibration method of an amphibious aircraft phased array weather radar provided by the present invention, the Z-axis coordinate value of the spherical reflector at the origin O, A, and C on the cursor board is 0;

[0033] The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0

[0034] The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the following conditions: Ro = RA = RB = RC = Rr;

[0035] The axis of the aircraft on the cursor board coincides with the axis of the aircraft body, the cursor board is perpendicular to the axis of the aircraft body, and the plane of the cursor board is parallel to the antenna radiation surface.

[0036] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation is provided. During the calibration process, an infrared switch on a calibration scope is turned on to obtain a red dot on the cursor plate plane, calibrating the actual aiming position of the calibration scope. The position of the red dot on the cursor plate is compared with a predetermined aiming point, and the aiming angle of the calibration scope is adjusted until the red dot coincides with the aiming point.

[0037] Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

[0038] According to a method for calibrating an amphibious aircraft phased array weather radar installation, during the calibration of the weather radar, the horizontal distance between the actual aiming center of the calibration scope and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes:

[0039] Azimuth error = atan(Eaz / R);

[0040] Pitch error = atan(Eel / R);

[0041] Radar antenna cursor plate distance R, R = Rr + Dx;

[0042] Connect the debugging computer to the radar and write the calculated azimuth error and pitch error into the radar processing unit to complete the weather radar calibration.

[0043] It can be seen that the present invention has the following beneficial effects:

[0044] 1. The present invention uses a laser tracking system to accurately track N horizontal measurement points on the aircraft fuselage, which can create a high-precision current aircraft coordinate system, ensuring the basic accuracy of subsequent calibration work and helping to improve the overall performance of the radar system.

[0045] 2. The entire calibration process of this invention combines digital modeling (such as the digital model of the machine body and calibration tool) with automated measurement technologies (such as laser tracking and coordinate correction), reducing human error and improving calibration efficiency and accuracy. The use of digital models also makes the calibration process more intuitive and easy to understand.

[0046] 3. The steps of correcting the cursor plate position in the method of the present invention include placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor plate plane. These steps show a high degree of flexibility and can cope with the challenges of different aircraft shapes and installation conditions, ensuring the accuracy and reliability of calibration.

[0047] 4. The data obtained during the calibration process of the present invention is recorded in detail, and the calculated calibration results are input into the radar computer, which not only facilitates subsequent analysis and review, but also improves the traceability of the calibration results, which is helpful for problem troubleshooting and performance optimization.

[0048] 5. Strong adaptability: This method is not only applicable to amphibious aircraft, but its basic principles and technical means can also be extended to the calibration of other types of aircraft and radar systems, showing good adaptability and versatility.

[0049] 6. Through precise calibration, the present invention can ensure that the phased array weather radar can maintain high-performance operation under complex weather conditions and various flight states, improve the accuracy and reliability of meteorological observations, and provide strong protection for flight safety.

[0050] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The present invention is a flow chart of an embodiment of a method for calibrating an amphibious aircraft phased array weather radar installation.

[0052] Figure 2 The present invention is a schematic diagram of an embodiment of a method for calibrating an amphibious aircraft phased array weather radar installation, in which laser spherical reflectors are arranged at various distribution points on the fuselage.

[0053] Figure 3 The present invention is a schematic diagram of a target scope and a weather radar in an embodiment of a method for installing and calibrating a phased array weather radar for an amphibious aircraft.

[0054] Figure 4 The present invention is a schematic diagram of the position distribution of spherical reflectors on a cursor board in an embodiment of a method for installing and calibrating a phased array weather radar for an amphibious aircraft.

[0055] Figure 5The present invention is a schematic diagram of how to adjust the cursor plate plane in an embodiment of an installation and calibration method for an amphibious aircraft phased array weather radar.

[0056] Figure 6 The present invention is a schematic diagram of calculating the installation error of the radar antenna in an embodiment of the installation calibration method of the amphibious aircraft phased array weather radar.

[0057] Figure 7 The present invention is a schematic diagram of the installation of calibration tooling in an embodiment of an installation calibration method for an amphibious aircraft phased array weather radar.

[0058] Figure 8 The present invention is a schematic diagram of calibrating the theoretical horizontal plane and vertical axis of an amphibious aircraft body in an embodiment of a method for calibrating an amphibious aircraft phased array weather radar installation. DETAILED DESCRIPTION

[0059] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0060] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] See also Figures 1 to 8 This embodiment provides a method for calibrating an amphibious aircraft phased array weather radar installation, the method comprising the following steps:

[0062] Step S1, installing the calibration fixture and the laser calibration target mirror.

[0063] Step S2: Track N horizontal measurement points on the aircraft fuselage through the laser tracking system, and create a current aircraft full-machine coordinate system in the ground target station.

[0064] Step S3, calibrating the theoretical coordinate position of the calibration mirror laser emission point in the whole machine coordinate system based on the machine body and the calibration fixture digital model.

[0065] Step S4, correcting the position of the cursor pad, includes: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the plane of the cursor pad.

[0066] Step S5, calibrate the aiming position of the target mirror and input the calibration result, turn on the laser calibration target mirror, calibrate the aiming position of the target mirror on the cursor plate plane, record the data obtained during the calibration process, and input the calculated calibration result into the radar computer to complete the entire calibration process.

[0067] It can be seen that the present invention can solve the problem of high manpower, physical force and time costs in the process of leveling the aircraft during the calibration of airborne weather radar, and can also solve the problem of restrictions on flatness requirements in radar calibration sites.

[0068] Among them, this embodiment realizes the accurate modeling of the entire coordinate system of the current aircraft through the data import and preprocessing of steps S1 and S2; through step S3, the rapid positioning of the target mirror laser emission point is realized; through step S4, the spatial leveling of the cursor calibration target plate and the radar antenna is realized, which reduces the workload of leveling the aircraft, thereby saving costs and improving the efficiency and accuracy of the calibration process; through step S5, the platform's quick calibration inspection method is used, which has strong repeatability and can be calibrated multiple times to take the average, avoiding errors and inefficiencies introduced by human factors and ensuring the reliability of the calibration results.

[0069] In the above step S1, the calibration fixture and the laser calibration target mirror are installed, including:

[0070] The calibration tool is installed vertically above the weather radar, and the laser calibration mirror is installed offset on the top of the antenna, with its azimuth direction consistent with the direction of the aircraft body (along the heading) to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft, thereby improving the accuracy of the calibration.

[0071] The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

[0072] To ensure the required degree of coincidence between the reference of the mounting point and the aircraft's axis of symmetry, the aircraft's axis of symmetry can be accurately measured and marked before installation. Then, during installation, high-precision measurement tools (such as laser trackers and total stations) are used to monitor and calibrate the position and orientation of the mounting point to ensure that the required degree of coincidence with the aircraft's axis of symmetry is met.

[0073] In the above step S2, tracking N horizontal measurement points on the aircraft fuselage by a laser tracking system includes:

[0074] A laser tracking system (ranging accuracy 0.025mm) was selected, and 10 horizontal measurement points on the aircraft fuselage were selected as target points for establishing the coordinate system. These points were used to determine the spatial position and orientation of the aircraft. Specifically, there were 4 horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there were 6 horizontal measurement points on the aircraft fuselage, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail. Laser spherical reflectors were arranged at each distribution point, such as Figure 2 shown.

[0075] Specifically, the four horizontal measurement points on the bottom of the amphibious aircraft hull include:

[0076] Nose position: 1 left, 1 right, these two points are located on the left and right sides of the nose respectively, and are used to determine the horizontal position and direction of the nose.

[0077] Tail position: 2 Left and 2 Right. These two points are located on the left and right sides of the tail, corresponding to the measurement points on the nose. They are used to determine the horizontal position and direction of the tail and help establish the overall length and symmetry of the aircraft.

[0078] Six horizontal measurement points on the aircraft fuselage:

[0079] Nose position: 3 left and 3 right. These two points are located slightly behind the nose and complement the 1 left and 1 right points on the bottom of the hull to further refine the position and shape of the nose.

[0080] Middle fuselage: 4 Left and 4 Right, these two points are located on the left and right sides of the middle fuselage and are used to determine the horizontal position and direction of the middle fuselage, helping to establish the overall width and symmetry of the aircraft.

[0081] Tail position: 5 left and 5 right. These two points are located slightly in front of the tail and correspond to points 2 left and 2 right on the bottom of the hull, further refining the position and shape of the tail.

[0082] In the above step S2, the current aircraft full-machine coordinate system is created in the ground target station, including:

[0083] Use the ground target station software platform to establish the full aircraft coordinate system:

[0084] Establish a horizontal plane based on 3 left, 3 right and 4 left points;

[0085] The symmetry plane of the whole aircraft is established based on the midpoints of 1 left and 2 right and the midpoints of 2 left and 2 right;

[0086] The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

[0087] In the above step S3, the theoretical coordinate position of the emission point of the laser calibration scope is calibrated, including:

[0088] According to the digital-analog connection relationship between the laser calibration mirror and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emission point of the calibration mirror is calibrated according to the origin (0, 0, 0) of the whole aircraft coordinate system established by the target station software platform, and the pitch offset distance Dz of the target mirror is obtained, as shown in the following example: Figure 3 As shown in FIG, the distance represents the vertical offset of the laser emission point relative to the origin of the global coordinate system.

[0089] In the above step S4, the position of the cursor pad is corrected, including:

[0090] Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system;

[0091] Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line;

[0092] Based on the tracked coordinates, the offset of the cursor plate relative to the global coordinate system is calculated to correct the cursor plate position so that the cursor plate is at the position required by the radar calibration distance, that is, the origin of the cursor plate coincides with the origin of the global coordinate system;

[0093] Adjust the plane of the cursor board so that the aircraft axis on the cursor board coincides with the axis of the aircraft body, and adjust the position and posture of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body;

[0094] Ensure that the cursor board plane is parallel to the antenna radiating surface. This can be checked by placing a reference surface on the cursor board that is parallel to the antenna radiating surface and observing the gap or reflection between the two.

[0095] In the above step S4, when placing the spherical reflector, the four fixed adjustment points of the cursor plate are designated as the fixed positions of the spherical reflector, which are located at the origin, the horizontal line, and the vertical line, and are designated as the origin O, point A, point B, and point C. Figure 4 shown.

[0096] Preferably, in step S4, a laser tracking system is used to track the coordinates of the origin O and the spherical reflectors at points A, B, and C on the cursor board, and during the process of adjusting the plane of the cursor board, the coordinate data of the target station software platform is monitored in real time.

[0097] In the above step S4, the Z-axis coordinate value of the spherical reflector at the origin O, A, and C on the cursor board is 0;

[0098] The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0;

[0099] The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the following conditions: Ro = RA = RB = RC = Rr;

[0100] Among them, the aircraft axis on the cursor board coincides with the axis of the aircraft body, and the cursor board is perpendicular to the axis of the aircraft body, and the cursor board plane is parallel to the antenna radiation surface, such as Figure 5 shown.

[0101] In the above step S5, during the calibration process, by turning on the infrared switch on the calibration target scope, a red dot is obtained on the cursor board plane to calibrate the actual aiming position of the calibration target scope, such as Figure 6 As shown in the figure, compare the position of the red dot on the cursor board with the predetermined aiming point, and adjust the aiming angle of the calibration scope until the red dot and the aiming point coincide with each other;

[0102] Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

[0103] During the calibration process of the weather radar, the horizontal distance between the actual aiming center of the calibration scope and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes:

[0104] Azimuth error = atan(Eaz / R);

[0105] Pitch error = atan(Eel / R);

[0106] Radar antenna cursor plate distance R, R = Rr + Dx;

[0107] Connect the debugging computer to the radar and write the calculated azimuth error and pitch error into the radar processing unit to complete the weather radar calibration.

[0108] Furthermore, in the above step S1, the radome is removed and a calibration tool is installed. The tool installation needs to be aligned with the accuracy requirements of the meteorological radar system, including:

[0109] Installation fixing point: The reference coincides with the symmetry axis of the aircraft, and the error angle is less than 15'. The installation position is as follows Figure 7 shown.

[0110] Furthermore, in the above step S2, the whole aircraft coordinate system is established to generate a three-dimensional aircraft fuselage data model. The whole aircraft coordinate system is calibrated on the ground using a laser tracking system, a ground target station, fuselage positioning pins and a spherical reflector. The theoretical horizontal plane and vertical axis of the aircraft fuselage are calibrated by the horizontal measurement points of the fuselage vertical tail, as shown in the figure. Figure 8 shown.

[0111] Specifically, when using the ground target station software platform to establish the coordinate system of the entire aircraft, first prepare a suitable target according to the requirements of the software platform. The target should have feature points or marks that are easy to identify and measure. Place the targets at predetermined positions on the aircraft or related structures to ensure that they can accurately reflect the geometric characteristics of the entire aircraft. Start the ground target station software platform and perform necessary initialization settings. Use the software platform to control the measurement equipment (such as laser trackers, total stations, etc.) to accurately measure the feature points on the target and record the measurement data, including the three-dimensional coordinates of each feature point.

[0112] Then, an initial coordinate system is set in the software platform. The coordinate system can be a global coordinate system or any convenient local coordinate system. The collected data is processed, including data cleaning, denoising, fitting and other operations. Based on the processed data, the relative position relationship between the feature points on the target is calculated. Using the known target position relationship and the geometric characteristics of the entire aircraft, the initial coordinate system is converted into the full-aircraft coordinate system through mathematical transformations (such as rotation, translation, etc.). The parameters of the full-aircraft coordinate system are set in the software platform, including the coordinate origin, coordinate axis direction, etc. After the full-aircraft coordinate system is established, the software platform is used to measure other known points on the aircraft or related structures, and compare them with the theoretical values ​​to verify the accuracy of the coordinate system.

[0113] In summary, the present invention uses a laser tracking system to accurately track N horizontal measurement points on the aircraft fuselage, which can create a high-precision coordinate system for the entire current aircraft, ensure the basic accuracy of subsequent calibration work, and help improve the overall performance of the radar system. The entire calibration process of the present invention combines digital modeling (such as digital models of the fuselage and calibration tooling) and automated measurement technology (such as laser tracking and coordinate correction), which reduces human errors and improves calibration efficiency and accuracy. At the same time, the use of digital models also makes the calibration process more intuitive and easy to understand. The steps of correcting the cursor position in the method of the present invention include placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor plane. These steps show a high degree of flexibility and can cope with the challenges of different aircraft shapes and installation conditions, ensuring the accuracy and reliability of calibration. The data obtained during the calibration process of the present invention is recorded in detail, and the calculated calibration results are input into the radar computer, which not only facilitates subsequent analysis and review, but also improves the traceability of the calibration results, which is helpful for problem troubleshooting and performance optimization. This method is not only applicable to amphibious aircraft; its basic principles and technical means can also be extended to the calibration of other types of aircraft and radar systems, demonstrating excellent adaptability and versatility. Through precise calibration, this invention ensures that phased array weather radars maintain high performance in complex weather conditions and various flight states, improving the accuracy and reliability of meteorological observations and providing a strong guarantee for flight safety.

[0114] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A method for calibrating an amphibious aircraft phased array weather radar installation, characterized in that: The following steps are involved: Install calibration fixture and laser calibration target mirror; The laser tracking system is used to track N horizontal measurement points on the aircraft fuselage, and the current aircraft coordinate system is created on the ground target station; In the whole aircraft coordinate system, the theoretical coordinate position of the launch point of the laser calibration mirror is calibrated based on the aircraft body and calibration fixture digital model; Correcting the cursor plate position, including: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor plate plane; Calibrate the aiming position of the target scope and input the calibration results. Turn on the laser calibration scope and calibrate the aiming position of the laser calibration scope on the cursor plate plane. Record the data obtained during the calibration process and input the calculated calibration results into the radar computer to complete the entire calibration process.

2. The method according to claim 1, characterized in that The installation calibration fixture and laser calibration target mirror include: Install the calibration tool vertically above the weather radar, and install the laser calibration scope offset on the top of the antenna, with its azimuth consistent with the direction of the aircraft body to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft; The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

3. The method according to claim 1, characterized in that Tracking N horizontal measurement points on the aircraft fuselage by using a laser tracking system includes: Ten horizontal measurement points on the aircraft fuselage are selected as the target point distribution points for establishing the coordinate system, including four horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there are six horizontal measurement points on the aircraft fuselage, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail.

4. The method according to claim 3, characterized in that The step of creating the current aircraft's full coordinate system in the ground target station includes: Use the ground target station software platform to establish the full aircraft coordinate system: Establish a horizontal plane based on 3 left, 3 right and 4 left points; The symmetry plane of the whole aircraft is established based on the midpoints of 1 left and 2 right and the midpoints of 2 left and 2 right; The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

5. The method according to claim 1, characterized in that The method of calibrating the theoretical coordinate position of the emission point of the laser calibration scope includes: According to the digital-analog connection relationship between the laser calibration scope and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emission point of the laser calibration scope is calibrated according to the origin (0, 0, 0) of the global coordinate system established by the target station software platform, and the pitch offset distance Dz of the target scope is obtained. This distance represents the offset of the laser emission point in the vertical direction relative to the origin of the global coordinate system.

6. The method according to claim 1, characterized in that The method of correcting the cursor position includes: Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system; Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line; Based on the tracked coordinates, the offset of the cursor plate relative to the global coordinate system is calculated to correct the cursor plate position so that the cursor plate is at the position required by the radar calibration distance, that is, the origin of the cursor plate coincides with the origin of the global coordinate system; Adjust the plane of the cursor board so that the aircraft axis on the cursor board coincides with the axis of the aircraft body, and adjust the position and posture of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body; Make sure the cursor pad plane is parallel to the antenna radiating surface.

7. The method according to claim 6, characterized in that: When placing the spherical reflector, specify the four fixed adjustment points on the cursor plate as the fixed positions of the spherical reflector, which are located at the origin, horizontal line, and vertical line, and are proposed to be the origin O, point A, point B, and point C; A laser tracking system is used to track the coordinates of the origin O and the spherical reflectors at points A, B, and C on the cursor board. During the adjustment of the cursor board plane, the coordinate data of the target station software platform is monitored in real time.

8. The method according to claim 7, characterized in that: The Z-axis coordinate value of the spherical reflector at the origin O, A, and C on the cursor board is 0; The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0 The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the following conditions: Ro = RA = RB = RC = Rr; The axis of the aircraft on the cursor board coincides with the axis of the aircraft body, the cursor board is perpendicular to the axis of the aircraft body, and the plane of the cursor board is parallel to the antenna radiation surface.

9. The method according to any one of claims 1 to 8, characterized in that: During the calibration process, by turning on the infrared switch on the target scope, a red dot is obtained on the cursor board plane, and the actual aiming position of the target scope is calibrated. The position of the red dot on the cursor board is compared with the predetermined aiming point, and the aiming angle of the target scope is adjusted until the red dot coincides with the aiming point. Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

10. The method according to claim 9, characterized in that: During the calibration process of the weather radar, the horizontal distance between the actual aiming center of the calibration scope and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes: Azimuth error = atan(Eaz / R); Pitch error = atan(Eel / R); Radar antenna cursor plate distance R, R = Rr + Dx; Connect the debugging computer to the radar and write the calculated azimuth error and pitch error into the radar processing unit to complete the weather radar calibration.

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