Satellite navigation array antenna amplitude and phase calibration method and device

Abstract

The application provides a satellite navigation array antenna amplitude and phase calibration method and device, the method comprises the following steps: acquiring part of uniformly spaced elevation angle and azimuth angle information, collecting the amplitude and phase information of each channel at these angles, taking a channel as a reference, calculating the amplitude and phase error to be calibrated of each channel and the reference channel. According to the errors, an interpolation polynomial is constructed, and the size of the interpolation data set is determined. By traversing all angle points in the interpolation data set, the full-space fitting curve is obtained by using the interpolation method and curve fitting. According to the fitting curve, the amplitude and phase error correction value of each channel and the reference channel in the full space is reconstructed. The method does not depend on accurate turntable and slide rail, and can complete the amplitude and phase calibration in the full space, effectively reduces the calibration complexity and calibration time, greatly improves the calibration efficiency of the satellite navigation array antenna amplitude and phase error, and is convenient for engineering implementation.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation technology, and in particular to a satellite navigation array antenna amplitude and phase calibration method, a satellite navigation array antenna amplitude and phase calibration device, an electronic device, and a computer-readable medium. Background Art

[0002] The present invention relates to the field of satellite navigation and is applicable to satellite navigation array antennas. It is used to calibrate channel errors between channels of the array antenna, including amplitude and phase errors, to achieve anti-interference, beamforming, or DOA estimation functions. The array antenna frequency is not limited to Beidou, GPS, GLONASS, etc. The array antenna configuration is not limited to linear, square, circular, Y-shaped, planar, slanted, or spherical arrays, and the number of array antenna elements is no less than two.

[0003] Satellite navigation terminals are widely used in areas such as unmanned driving, positioning navigation, time services, and emergency rescue. However, in real-world environments, they are susceptible to various intentional or unintentional interference from space, such as radars, mobile base stations, and malicious interference or deceptive interference. This can lead to reduced positioning accuracy or even failure, seriously impacting user experience. To mitigate the effects of various electromagnetic interference, effective methods include antenna array anti-interference technology, employing algorithms such as spatial nulling and beam pointing to suppress interference. Alternatively, algorithms such as Direction of Arrival (DOA) estimation can be used to determine the direction of interference and assist the system in mitigating it.

[0004] In addition to being affected by the algorithm, interference rejection and DOA estimation accuracy are also affected by the physical properties of the array antenna, such as array flow pattern, inter-array coupling, hardware channel errors, and installation position errors. These factors can lead to large amplitude and phase errors between channels, resulting in degraded radiation patterns and severely impacting interference rejection, beam pointing, and DOA estimation performance. To ensure interference rejection, beam pointing accuracy, and DOA estimation precision, precise amplitude and phase error calibration is required for each channel of the antenna array. This ensures that the back-end digital processing follows the actual array flow pattern and produces accurate results.

[0005] In the prior art, the amplitude and phase error calibration of the array antenna at each incident angle is generally completed by relying on a microwave darkroom, using a turntable and a slide rail.

[0006] The shortcomings of the existing technology mainly include the following points:

[0007] (1) It relies on hardware facilities such as microwave darkroom, turntable, slide rail, etc., and the turntable and slide rail require high precision;

[0008] (2) The calibration efficiency is low. To complete the coverage of the entire airspace, each angle needs to be calibrated, which takes a long time and is difficult to engineer. Summary of the Invention

[0009] In view of the above problems, the present invention is proposed to provide a satellite navigation array antenna amplitude and phase calibration method and a corresponding satellite navigation array antenna amplitude and phase calibration device, an electronic device and a computer-readable medium that overcome the above problems or at least partially solve the above problems.

[0010] The present invention discloses a method for calibrating the amplitude and phase of a satellite navigation array antenna, the method comprising:

[0011] Acquiring some evenly spaced elevation angle information and azimuth angle information, and collecting amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information;

[0012] Taking a certain channel as a reference, calculating the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced pitch angle information and azimuth angle information;

[0013] constructing an interpolation polynomial for the array antenna according to the amplitude error and phase error between each channel and a reference channel under the evenly spaced elevation angle information and azimuth angle information;

[0014] Determine the size of the interpolation dataset and construct the interpolation dataset;

[0015] Traversing all azimuth points at each pitch angle and all pitch angle points at each azimuth in the interpolation data set, performing interpolation calculation and curve fitting based on the interpolation polynomial using an interpolation method, and obtaining fitting curves for all azimuths and pitch angles in the entire airspace;

[0016] According to the fitting curves of all azimuth and elevation angles in the entire airspace, the amplitude error correction value and phase error correction value between each channel of the array antenna and the reference channel at all azimuth and elevation angles in the entire airspace are reconstructed.

[0017] Optionally, determine the size of the interpolation dataset and construct the interpolation dataset, including:

[0018] Determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles;

[0019] According to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval, all azimuth angles are interpolated row by row based on each pitch angle to generate an interpolation data set;

[0020] and,

[0021] According to the number of interpolation intervals of the interpolation dataset and the number of data points contained in each interpolation interval, all pitch angles are interpolated column by column based on each azimuth angle to generate an interpolation dataset.

[0022] Optionally, determining the number of interpolation intervals of the interpolation data set and the number of data points included in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles includes:

[0023] Adjust the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the array antenna pattern at different elevation angles;

[0024] If the change rate of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals in the interpolation data set is reduced and the number of data points in each interpolation interval is increased;

[0025] If the change rate of the CNR jitter curve of the array antenna at the pitch angle is greater than the preset jitter threshold, the number of interpolation intervals of the interpolation data set is increased and the number of data points contained in each interpolation interval is reduced.

[0026] Optionally, the number of interpolation intervals is greater than 2, more preferably 2 to 8; and each interpolation interval contains at least 4 data points.

[0027] Optionally, the method further includes:

[0028] If the rate of change of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals is preferably 2 to 4; if the rate of change of the CNR jitter curve of the array antenna at the pitch angle is greater than or equal to the preset jitter threshold, the number of interpolation intervals is more than 4, and further preferably 4 to 8.

[0029] Optionally, the interpolation method includes Lagrange interpolation method and Newton interpolation method.

[0030] Optionally, obtaining some evenly spaced elevation angle information and azimuth angle information, and collecting amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information, includes:

[0031] Partially evenly spaced pitch angle information and azimuth angle information are acquired through the turntable and the slide rail, and amplitude information and phase information of each channel of the array antenna under the evenly spaced pitch angle information and azimuth angle information are acquired through the built-in processor of the array antenna.

[0032] The present invention also discloses a satellite navigation array antenna amplitude and phase calibration device, the device comprising:

[0033] An amplitude and phase information acquisition module is used to obtain some evenly spaced elevation angle information and azimuth angle information, and to acquire amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information;

[0034] An amplitude and phase error calculation module is used to calculate the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced pitch angle information and azimuth angle information, taking a certain channel as a reference benchmark;

[0035] An interpolation polynomial construction module is used to construct an interpolation polynomial of the array antenna according to the amplitude error and phase error between each channel and the reference channel under the evenly spaced elevation angle information and azimuth angle information;

[0036] An interpolation dataset construction module, used to determine the size of the interpolation dataset and construct the interpolation dataset;

[0037] An interpolation fitting module is used to traverse all azimuth points at each pitch angle and all pitch angle points at each azimuth in the interpolation data set, perform interpolation calculation and curve fitting based on the interpolation polynomial using an interpolation method, and obtain fitting curves for all azimuths and pitch angles in the entire airspace;

[0038] The amplitude and phase error reconstruction module is used to reconstruct the amplitude error correction value and phase error correction value between each channel of the array antenna and the reference channel at all azimuth and elevation angles in the entire airspace based on the fitting curve of all azimuth and elevation angles in the entire airspace.

[0039] Optionally, the interpolation dataset construction module includes:

[0040] The interpolation interval and point number determination submodule is used to determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles;

[0041] A first interpolation data set generation submodule is configured to interpolate all azimuth angles row by row based on each pitch angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval to generate an interpolation data set;

[0042] and,

[0043] The second interpolation data set generation submodule is used to interpolate all pitch angles in columns based on each azimuth angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval to generate an interpolation data set.

[0044] Optionally, the interpolation interval and point number determination submodule includes:

[0045] An interpolation interval and point number adjusting unit is configured to adjust the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the directivity irregularity of the array antenna at different elevation angles.

[0046] A small jitter adjusting unit is configured to reduce the number of interpolation intervals of the interpolation data set and increase the number of data points contained in each interpolation interval if the change rate of the CNR jitter curve of the array antenna at the elevation angle is less than the preset jitter threshold.

[0047] A large jitter adjusting unit is configured to increase the number of interpolation intervals of the interpolation data set and reduce the number of data points contained in each interpolation interval if the change rate of the CNR jitter curve of the array antenna at the elevation angle is greater than the preset jitter threshold.

[0048] Optionally, the number of interpolation intervals is greater than 2, and is further preferably 2-8; and the number of data points contained in each interpolation interval is at least 4.

[0049] Optionally, the device further comprises:

[0050] An interpolation interval number determining unit is configured to, if the change rate of the CNR jitter curve of the array antenna at the elevation angle is less than the preset jitter threshold, set the number of interpolation intervals to preferably 2-4; and if the change rate of the CNR jitter curve of the array antenna at the elevation angle is greater than or equal to the preset jitter threshold, set the number of interpolation intervals to greater than 4, and further preferably 4-8.

[0051] Optionally, the interpolation method comprises a Lagrange interpolation method or a Newton interpolation method.

[0052] Optionally, the amplitude and phase information acquisition module comprises:

[0053] An amplitude and phase information acquisition sub-module is configured to acquire part of uniformly spaced elevation angle information and azimuth angle information through a turntable and a slide rail, and acquire amplitude information and phase information of each channel of the array antenna at the uniformly spaced elevation angle information and azimuth angle information through an array antenna built-in processor.

[0054] The application further discloses an electronic device comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete communication with each other through the communication bus.

[0055] The memory is used to store a computer program.

[0056] The processor is used to execute the program stored on the memory, and implement the satellite navigation array antenna amplitude and phase calibration method.

[0057] The present invention also discloses one or more computer-readable media having instructions stored thereon, which, when executed by one or more processors, enable the processors to execute the satellite navigation array antenna amplitude and phase calibration method as described in the present invention.

[0058] The present invention includes the following advantages:

[0059] The satellite navigation array antenna amplitude and phase calibration method of the present invention obtains partially evenly spaced pitch angle information and azimuth angle information, and collects amplitude information and phase information of each channel of the array antenna under these pitch angle information and azimuth angle information, takes a certain channel as a reference benchmark, calculates the amplitude error to be calibrated and the phase error to be calibrated between each channel and a reference channel under these pitch angle information and azimuth angle information, constructs an interpolation polynomial of the array antenna based on the amplitude error and phase error between each channel and the reference channel under these pitch angle information and azimuth angle information, determines the size of an interpolation data set and constructs the interpolation data set, traverses all azimuth angle points under each pitch angle and all pitch angle points under each azimuth angle in the interpolation data set, performs interpolation calculation and curve fitting based on the interpolation polynomial, obtains fitting curves for all azimuth angles and pitch angles in the entire airspace, and reconstructs amplitude error correction values ​​and phase error correction values ​​between each channel of the array antenna and the reference channel under all azimuth angles and pitch angles in the entire airspace based on the fitting curves for all azimuth angles and pitch angles in the entire airspace. The method of the present invention does not rely on precise turntables and slide rails, and can complete amplitude and phase calibration in the entire airspace, effectively reducing calibration complexity and calibration time, greatly improving the calibration efficiency of satellite navigation array antenna amplitude and phase errors, and facilitating engineering implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 This is a flowchart of the steps of a satellite navigation array antenna amplitude and phase calibration method provided by an embodiment of the present invention;

[0061] Figure 2 This is a schematic diagram of the installation and operation of the amplitude and phase calibration equipment in a microwave darkroom provided by an embodiment of the present invention;

[0062] Figure 3 This is a flow chart of the amplitude and phase calibration of a satellite navigation array antenna provided by an embodiment of the present invention;

[0063] Figure 4 is the satellite navigation array antenna pattern provided by an embodiment of the present invention;

[0064] Figure 5 This is a structural block diagram of a satellite navigation array antenna amplitude and phase calibration device provided by an embodiment of the present invention;

[0065] Figure 6 is a block diagram of an electronic device provided by an embodiment of the present invention;

[0066] Figure 7 It is a schematic diagram of a computer-readable medium provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0067] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0068] Reference Figure 1 , shows a flowchart of the steps of a satellite navigation array antenna amplitude and phase calibration method provided in an embodiment of the present invention, which may specifically include the following steps:

[0069] Step 101: Acquire some evenly spaced elevation angle information and azimuth angle information, and collect amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information;

[0070] Step 102, taking a certain channel as a reference, calculating the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced pitch angle information and azimuth angle information;

[0071] Step 103, constructing an interpolation polynomial for the array antenna according to the amplitude error and phase error between each channel and the reference channel under the evenly spaced elevation angle information and azimuth angle information;

[0072] Step 104, determining the size of the interpolation dataset and constructing the interpolation dataset;

[0073] Step 105: traverse all azimuth points at each pitch angle and all pitch angle points at each azimuth in the interpolation data set, perform interpolation calculation and curve fitting based on the interpolation polynomial using an interpolation method, and obtain fitting curves for all azimuths and pitch angles in the entire airspace;

[0074] Step 106 : reconstructing the amplitude error correction value and the phase error correction value between each channel of the array antenna and the reference channel at all azimuth angles and elevation angles in the entire airspace based on the fitting curves of all azimuth angles and elevation angles in the entire airspace.

[0075] Under normal conditions, azimuth and pitch angle information is generally obtained through a turntable and a slide rail. When a turntable and a slide rail are not available, azimuth and pitch angle information can also be obtained through other means, as long as the accuracy is guaranteed.

[0076] The following describes the satellite navigation array antenna amplitude and phase calibration method of the present invention by taking the acquisition of azimuth and elevation angle information by a turntable and a slide rail as an example:

[0077] The amplitude and phase error calibration method of the present invention is performed in a microwave anechoic chamber and requires instruments and equipment such as a programmable slide, a two-dimensional turntable (or a three-dimensional turntable), a computer, a signal generator, and a transmitting antenna. The functions of the instruments and equipment are described below:

[0078] Microwave anechoic chamber is used to create a clean electromagnetic environment to prevent interference from other spaces.

[0079] The programmable slide rail is used to adjust the incident pitch angle of the transmitting antenna, and the supported angle range is at least 0°~90° (0° is the horizontal plane and 90° is the zenith).

[0080] A two-dimensional turntable (or three-dimensional turntable) is used to carry the array antenna for horizontal circular rotation, traversing the azimuth angle of 0°~360°.

[0081] Computers are used for data processing and may be replaced by other storage devices.

[0082] The signal generator is used to generate a calibration signal, generally using a single-tone continuous wave. The output of the signal generator is connected to the transmitting antenna.

[0083] The transmitting antenna is used to transmit the calibration signal, and its input is the output of the signal generator.

[0084] The installation and operation diagram of the device under test in a microwave darkroom environment is as follows: Figure 2 shown.

[0085] Reference Figure 3 The operation process of amplitude and phase calibration of this scheme is as follows:

[0086] 1. Place the satellite navigation array antenna to be calibrated horizontally at the center of the 2D turntable, directly below the transmitting antenna. The 2D turntable must be kept horizontal, and the center point remains unchanged after rotating 360°. The normal of the array antenna must always point 90° toward the zenith.

[0087] 2. Use a signal generator to generate a single-tone continuous wave and transmit it through the transmitting antenna. The frequency of this continuous wave must be within the frequency range that the array antenna can effectively process, and the amplitude of the continuous wave must be able to be effectively captured by the processor built into the array antenna;

[0088] 3. Adjust the programmable slide rail, set the pitch angle to 90° (zenith direction), and control the turntable to rotate horizontally at a constant speed according to a certain step M to complete the 0-360° traversal; when the turntable starts to rotate, use a computer or other storage device to record the output data to be calibrated. This data is the real-time data output by each channel, including the original amplitude and phase information;

[0089] 4. After the turntable returns to the starting point (azimuth angle 0°), adjust the programmable slide rail and set the pitch angle to other angle values ​​according to a certain step N, and repeat step 3;

[0090] 5. Follow steps 3 and 4 to complete the azimuth information at L pitch angles and summarize all the raw data;

[0091] 6. Using the original data, taking one of the channels as a reference, calculate the amplitude and phase errors between the channels;

[0092] 7. Construct an interpolation polynomial based on the amplitude and phase errors of each channel.

[0093] 8. According to the number of azimuth points at each pitch angle and the number of pitch points at each azimuth angle, interpolation is performed using the interpolation method to obtain the fitting curves of all azimuth and pitch angles in the entire airspace;

[0094] Interpolation is a key factor, directly impacting the accuracy of the fitted curves for each pitch and azimuth angle. Because the original data is obtained through measurement, each set of data is the exact value at that angle. The interpolation curve must pass through all measured data points; otherwise, errors will occur. Therefore, interpolation methods that cannot pass through all data points, such as the least squares method, should not be used.

[0095] Interpolation methods such as Newton interpolation and Lagrange interpolation can be used; other interpolation methods can also be used to complete curve fitting, not limited to Lagrange and Newton interpolation methods, but it is necessary to ensure that the fitted curve passes through all measured points, that is, the known coordinates of the interpolation.

[0096] If the data set size used for each interpolation polynomial fit is not appropriately selected, interpolation failure can occur. Therefore, to prevent interpolation divergence due to data sets of varying sizes, the specific data size must be carefully estimated. In the present invention, the CNR jitter curve can be used for estimation to prevent data divergence during the interpolation process. However, this is not limited to using CNR jitter as a decision point; other methods can also be used, such as directly determining the difference between the previous and next data, which can also serve as a basis for determining whether divergence has occurred.

[0097] 9. Based on all the fitted curves, the amplitude and phase error values ​​of each channel covering all azimuth and elevation angles in the entire airspace can be reconstructed;

[0098] 10. Write the amplitude and phase error values ​​covering the entire spatial domain generated by fitting into the lookup table for back-end algorithm calls.

[0099] The above process completes full-space amplitude and phase calibration for an array antenna. The azimuth step value, M, and elevation step value, N, can be adjusted based on actual needs. These two step values ​​affect calibration time and final calibration accuracy. To facilitate engineering implementation, the recommended azimuth and elevation step values ​​are in the range of 5 to 10.

[0100] In one embodiment of the present invention, determining the size of the interpolation dataset and constructing the interpolation dataset includes:

[0101] Determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles;

[0102] According to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval, all azimuth angles are interpolated row by row based on each pitch angle to generate an interpolation data set;

[0103] and,

[0104] According to the number of interpolation intervals of the interpolation dataset and the number of data points contained in each interpolation interval, all pitch angles are interpolated column by column based on each azimuth angle to generate an interpolation dataset.

[0105] In one embodiment of the present invention, determining the number of interpolation intervals of the interpolation data set and the number of data points included in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles includes:

[0106] Adjust the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the array antenna pattern at different elevation angles;

[0107] If the change rate of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals in the interpolation data set is reduced and the number of data points in each interpolation interval is increased;

[0108] If the change rate of the CNR jitter curve of the array antenna at the pitch angle is greater than the preset jitter threshold, the number of interpolation intervals of the interpolation data set is increased and the number of data points contained in each interpolation interval is reduced.

[0109] In an embodiment of the present invention, the number of interpolation intervals is more than 2, more preferably 2 to 8; and each interpolation interval contains at least 4 data points.

[0110] In one embodiment of the present invention, the method further comprises:

[0111] If the rate of change of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals is preferably 2 to 4; if the rate of change of the CNR jitter curve of the array antenna at the pitch angle is greater than or equal to the preset jitter threshold, the number of interpolation intervals is more than 4, and further preferably 4 to 8.

[0112] For the interpolation process and curve fitting method described in steps 6 to 10 above, the Lagrange interpolation method is used as an example to illustrate the implementation steps:

[0113] Given the limited amount of data from satellite navigation array antennas, for example, if the pitch angle is 0° to 90° and is measured in 5° steps, the actual number of pitch angle points corresponding to each azimuth angle is 0°, 5°, ..., 90°, for a total of 19 points. If the azimuth angle is 0° to 360° and is measured in 5° steps, the actual number of azimuth angle points corresponding to each pitch angle is 0°, 5°, ..., 350° (0° and 360° overlap and represent 1 point), for a total of 72 points. Therefore, the amount of data for each set of pitch angle vectors and azimuth angle vectors is relatively small, making it suitable to use interpolation methods with better performance for small data sets, such as Lagrange or Newton interpolation. Taking the Lagrange interpolation method as an example, the interpolation polynomial is:

[0114]

[0115] in,

[0116]

[0117] is a known point, .

[0118] By using the above interpolation formula and the actual measured data, other approximate values ​​in the known interval can be obtained. The Lagrange interpolation method is implemented as follows:

[0119] 1) Raw data processing

[0120] Assuming the azimuth angle step is 5° and the elevation angle step is 5°, the correction value of one channel of the original measurement is:

[0121] d(0°,0°), d(0°,5°), d(0°,10°), ..., d(0°,355°)

[0122] d(5°,0°), d(5°,5°), d(5°,10°), ..., d(5°,355°) ...

[0123] d(85°,0°), d(85°,5°), d(85°,10°), ..., d(85°,355°)

[0124] d(90°,0°)

[0125] Among them, the correction value , is the pitch angle, is the azimuth. , is the number of array antenna channels. When the elevation angle is 90°, all azimuth angles are the same, so only one value is taken. The other azimuth angles can use the value of 0° azimuth. .

[0126] 2) Based on each pitch angle , interpolating all azimuths by row, we can get:

[0127] d(0°,0°), d(0°,1°), d(0°,2°), ..., d(0°,358°), d(0°,359°),

[0128] d(5°,0°), d(5°,1°), d(5°,2°), ..., d(5°,358°), d(5°,359°), ...

[0129] d(85°,0°), d(85°,1°), d(85°,2°), ..., d(85°,358°), d(85°,359°),

[0130] d(90°,0°)

[0131] This step can be completed by interpolating all points at once, or by performing interpolation in two or more intervals. For example, if the data is divided into two intervals, the corresponding azimuth angles for each pitch angle can be [0, 5, ..., 175] as one interval, and [180, 190, ..., 355] as another interval, and interpolated separately. After interpolation is complete, the data is merged into a complete data segment. The interpolation of the pitch angle can also be performed in multiple intervals.

[0132] To ensure the fitting effect, it is recommended that the number of interpolation intervals for each row of data be 2 to 8. If the data curve is more complex, the maximum value can be greater than 8, and each interval contains no less than 4 data points.

[0133] 3) Based on each azimuth , interpolating all pitch angles by column, we can get:

[0134] d(0°,0°), d(0°,1°), d(0°,2°), ..., d(0°,358°), d(0°,359°),

[0135] d(1°,0°), d(1°,1°), d(1°,2°), ..., d(1°,358°), d(1°,359°),

[0136] d(2°,0°), d(2°,1°), d(2°,2°), ..., d(2°,358°), d(2°,359°), ...

[0137] d(88°,0°), d(88°,1°), d(88°,2°), ..., d(88°,358°), d(88°,359°),

[0138] d(89°,0°), d(89°,1°), d(89°,2°), ..., d(89°,358°), d(89°,359°),

[0139] d(90°,0°)

[0140] 4) Follow steps 1) to 3) to complete the azimuth and elevation interpolation of other channels;

[0141] 5) The generated All amplitude and phase correction values ​​for each channel, azimuth and elevation angles in 1° steps, are written into the lookup table.

[0142] The five steps above complete full-space amplitude and phase calibration, ready for use by back-end anti-interference or DOA algorithms. As can be seen from the preceding steps, obtaining raw values ​​through step measurement and then calibrating via interpolation significantly improves efficiency. For both azimuth and elevation, a 5° / s step size reduces calibration time by approximately 25 times (compared to 1° / s). A 10° / s step size reduces calibration time by approximately 100 times.

[0143] For datasets of varying sizes, interpolation methods may diverge. This is illustrated below using the CNR jitter curve as an example:

[0144] That is, based on the non-circularity characteristics of the satellite navigation array antenna's pattern at different elevation angles, CNR jitter is used as a decision on the data size of the interpolated data set.

[0145] Because the amount of data in the data set will affect the interpolation accuracy, when the amount of data is large or the curve is complex, the interpolation algorithm may diverge. In actual array antennas, the radiation patterns vary greatly at different elevation angles. Figure 4 :as shown in a)~d). Figure 4This is the radiation pattern of one element of the array antenna at different elevation angles. It can be seen from the radiation pattern that there is a significant difference between the low elevation angle and high elevation angle radiation patterns. The higher the elevation angle, the better the skewness and the smaller the concavity; the lower the elevation angle, the worse the skewness and the larger the concavity.

[0146] Generally speaking, the higher the elevation angle, the better the pattern's non-circularity, and the closer the corresponding curve for each channel is to the ideal model. Conversely, the lower the pitch angle, the worse the pattern's non-circularity, and the greater the deviation from the ideal model and the more complex the corresponding curve for each channel. For patterns with larger or more irregular curves at low elevation angles, the interpolation dataset must be limited, as this will cause some interpolation points to diverge. Therefore, the number of interpolation points should be selected based on the specific situation. CNR (Constant Noise Ratio) is a common measurement used to assess the pattern non-circularity of satellite navigation array antennas at different elevation angles. CNR jitter reflects the gain of the antenna pattern, so the CNR curve can be used as an estimation parameter for the size of the interpolation dataset. Greater CNR jitter indicates worse antenna non-circularity, and the number of interpolation dataset points can be appropriately reduced. Lower CNR jitter indicates better antenna non-circularity, and the number of interpolation dataset points can be appropriately increased. The steps for determining the interpolation data size based on CNR jitter are as follows.

[0147] 1. Obtain CNR jitter curves at different pitch angles;

[0148] 2. Divide all data sets into N sub-intervals according to the CNR jitter curve;

[0149] 3. For smoother CNR curves, it is recommended that N be set to 2-4. For larger CNR jitter, it is recommended that N be set to 4-8. If the data curve is more complex, the maximum value can be greater than 8.

[0150] by Figure 4 Take the directional diagram as an example (equivalent to the CNR jitter curve):

[0151] 1. Figure 4 In a) and b), the overall curves for the 70° and 60° patterns are relatively smooth. Therefore, the data set at this elevation angle [-180°:180°] can be divided into 90-degree intervals, with a total of four intervals [180°:-90°], [-90°:0°], [0°:90°], and [90°:180°].

[0152] 2. Figure 4 In c) of the 30° pattern, there is significant jitter in the interval [-90°:0°]. This interval can be further divided into two intervals, namely [-90°:-45°] and [-45°:0°]. For other intervals, refer to step 1.

[0153] 3. Figure 4In (d) of the 10° pattern, there are significant dips at [180°:-90°] and [-90°:0°]. These two intervals are then further subdivided into two subintervals: the original [180°:-90°] interval is further divided into [180°:-145°] and [-145°:-90°] intervals; and the original [-90°:0°] interval is further divided into [-90°:-45°] and [-45°:0°] intervals. For other intervals, refer to step 1.

[0154] If the obtained CNR pattern is more complex, the number of sub-intervals can be further increased, and the intervals are not limited to a range of 90°.

[0155] Using CNR jitter as the criterion for determining the size of the interpolation dataset can adjust the size of the interpolation dataset based on the out-of-roundness characteristics of different pitch angles, preventing interpolation divergence and improving calibration accuracy and stability.

[0156] It should be noted that for the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0157] Reference Figure 5 , shows a structural block diagram of a satellite navigation array antenna amplitude and phase calibration device provided in an embodiment of the present invention, which may specifically include the following modules:

[0158] Amplitude and phase information acquisition module 501 is used to obtain some evenly spaced elevation angle information and azimuth angle information, and to acquire amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information;

[0159] The amplitude and phase error calculation module 502 is configured to calculate the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced elevation angle information and azimuth angle information, taking a certain channel as a reference;

[0160] An interpolation polynomial construction module 503 is configured to construct an interpolation polynomial for the array antenna based on the amplitude error and phase error between each channel and the reference channel under the evenly spaced elevation angle information and azimuth angle information;

[0161] An interpolation data set construction module 504 is used to determine the size of the interpolation data set and construct the interpolation data set;

[0162] The interpolation fitting module 505 is configured to traverse all azimuth angle points at each elevation angle and all elevation angle points at each azimuth angle in the interpolation data set, and perform interpolation calculation and curve fitting based on an interpolation polynomial to obtain fitting curves of all azimuth angles and elevation angles in the full airspace.

[0163] The amplitude-phase error reconstruction module 506 is configured to reconstruct amplitude error correction values and phase error correction values between each channel of the array antenna and the reference channel at all azimuth angles and elevation angles in the full airspace according to the fitting curves of all azimuth angles and elevation angles in the full airspace.

[0164] Optionally, the interpolation data set construction module comprises:

[0165] The interpolation interval and point number determination sub-module is configured to determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the directivity non-circularity of the array antenna at different elevation angles.

[0166] The first interpolation data set generation sub-module is configured to generate the interpolation data set by interpolating all azimuth angles by row based on each elevation angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval.

[0167] and,

[0168] The second interpolation data set generation sub-module is configured to generate the interpolation data set by interpolating all elevation angles by column based on each azimuth angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval.

[0169] Optionally, the interpolation interval and point number determination sub-module comprises:

[0170] The interpolation interval and point number adjustment unit is configured to adjust the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the directivity non-circularity of the array antenna at different elevation angles.

[0171] The small jitter adjustment unit is configured to reduce the number of interpolation intervals of the interpolation data set and increase the number of data points contained in each interpolation interval if the rate of change of the CNR jitter curve of the array antenna at the elevation angle is less than the preset jitter threshold.

[0172] The large jitter adjustment unit is configured to increase the number of interpolation intervals of the interpolation data set and reduce the number of data points contained in each interpolation interval if the rate of change of the CNR jitter curve of the array antenna at the elevation angle is greater than the preset jitter threshold.

[0173] Optionally, the number of interpolation intervals is greater than 2, and is further preferably 2-8; and the number of data points contained in each interpolation interval is at least 4.

[0174] Optionally, the device further comprises:

[0175] The interpolation interval number determination unit is used to determine that if the rate of change of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals is preferably 2 to 4; if the rate of change of the CNR jitter curve of the array antenna at the pitch angle is greater than or equal to the preset jitter threshold, the number of interpolation intervals is more than 4, and is further preferably 4 to 8.

[0176] Optionally, the interpolation method includes Lagrange interpolation method and Newton interpolation method.

[0177] Optionally, the amplitude and phase information acquisition module includes:

[0178] The amplitude and phase information acquisition submodule is used to obtain some evenly spaced pitch angle information and azimuth angle information through the turntable and the slide rail, and to acquire the amplitude information and phase information of each channel of the array antenna under the evenly spaced pitch angle information and azimuth angle information through the built-in processor of the array antenna.

[0179] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0180] In addition, an embodiment of the present invention further provides an electronic device, such as Figure 6 As shown, it includes a processor 601, a communication interface 602, a memory 603 and a communication bus 604, wherein the processor 601, the communication interface 602, and the memory 603 communicate with each other through the communication bus 604.

[0181] Memory 603, used for storing computer programs;

[0182] The processor 601 is configured to implement the satellite navigation array antenna amplitude and phase calibration method described in the above embodiment when executing the program stored in the memory 603 .

[0183] The communication bus mentioned in the terminal can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. This communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is used in the figure, but this does not mean that there is only one bus or only one type of bus.

[0184] The communication interface is used for communication between the above terminal and other devices.

[0185] The memory may include random access memory (RAM) or non-volatile memory, such as at least one disk storage. Alternatively, the memory may be at least one storage device located away from the processor.

[0186] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components.

[0187] like Figure 7 As shown, in another embodiment provided by the present invention, a computer-readable storage medium 701 is also provided, which stores instructions. When the computer-readable storage medium is run on a computer, it enables the computer to execute the satellite navigation array antenna amplitude and phase calibration method described in the above embodiment.

[0188] In another embodiment of the present invention, a computer program product including instructions is provided. When the computer program product is run on a computer, the computer executes the satellite navigation array antenna amplitude and phase calibration method described in the above embodiment.

[0189] In the above embodiments, all or part of the embodiments can be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disk, hard disk, tape), optical media (e.g., DVD), or semiconductor media (e.g., solid-state disk (SSD)).

[0190] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0191] Each embodiment in this specification is described in a related manner. Similar portions between the embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences from other embodiments. In particular, the device embodiments are generally similar to the method embodiments, so their description is relatively simple. For related portions, refer to the description of the method embodiments.

[0192] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

Claims

1. A method for calibrating the amplitude and phase of a satellite navigation array antenna, characterized in that: The method comprises: Acquiring some evenly spaced elevation angle information and azimuth angle information, and collecting amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information; Taking a certain channel as a reference, calculating the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced pitch angle information and azimuth angle information; constructing an interpolation polynomial for the array antenna according to the amplitude error and phase error between each channel and a reference channel under the evenly spaced elevation angle information and azimuth angle information; Determine the size of the interpolation dataset and construct the interpolation dataset; Traversing all azimuth points at each pitch angle and all pitch angle points at each azimuth in the interpolation data set, performing interpolation calculation and curve fitting based on the interpolation polynomial using an interpolation method, and obtaining fitting curves for all azimuths and pitch angles in the entire airspace; Based on the fitting curves of all azimuth and elevation angles in the entire airspace, the amplitude error correction value and phase error correction value between each channel of the array antenna and the reference channel at all azimuth and elevation angles in the entire airspace are reconstructed; Determine the interpolation dataset size and construct the interpolation dataset, including: Determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles; According to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval, all azimuth angles are interpolated row by row based on each pitch angle to generate an interpolation data set; and, According to the number of interpolation intervals of the interpolation dataset and the number of data points contained in each interpolation interval, all pitch angles are interpolated column by column based on each azimuth angle to generate an interpolation dataset.

2. The method according to claim 1, characterized in that The number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval are determined based on the non-circularity of the array antenna pattern at different elevation angles, including: Adjust the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the array antenna pattern at different elevation angles; If the change rate of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals in the interpolation data set is reduced and the number of data points in each interpolation interval is increased; If the change rate of the CNR jitter curve of the array antenna at the pitch angle is greater than the preset jitter threshold, the number of interpolation intervals of the interpolation data set is increased and the number of data points contained in each interpolation interval is reduced.

3. The method according to claim 1, characterized in that The number of interpolation intervals is greater than 2, and further ranges from 2 to 8; and each interpolation interval contains at least 4 data points.

4. The method according to claim 2, characterized in that The method further comprises: If the rate of change of the CNR jitter curve of the array antenna at the pitch angle is less than the preset jitter threshold, the number of interpolation intervals is 2 to 4; if the rate of change of the CNR jitter curve of the array antenna at the pitch angle is greater than or equal to the preset jitter threshold, the number of interpolation intervals is more than 4, and further 4 to 8.

5. The method according to claim 1, wherein The interpolation method includes Lagrange interpolation method and Newton interpolation method.

6. The method according to claim 1, characterized in that Acquiring some evenly spaced elevation angle information and azimuth angle information, and collecting amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information, including: Partially evenly spaced pitch angle information and azimuth angle information are acquired through the turntable and the slide rail, and amplitude information and phase information of each channel of the array antenna under the evenly spaced pitch angle information and azimuth angle information are acquired through the built-in processor of the array antenna.

7. A satellite navigation array antenna amplitude and phase calibration device, characterized in that: The device comprises: An amplitude and phase information acquisition module is used to obtain some evenly spaced elevation angle information and azimuth angle information, and to acquire amplitude information and phase information of each channel of the array antenna under the evenly spaced elevation angle information and azimuth angle information; An amplitude and phase error calculation module is used to calculate the amplitude error to be calibrated and the phase error to be calibrated between each channel and the reference channel under the evenly spaced pitch angle information and azimuth angle information, taking a certain channel as a reference benchmark; An interpolation polynomial construction module is used to construct an interpolation polynomial of the array antenna according to the amplitude error and phase error between each channel and the reference channel under the evenly spaced elevation angle information and azimuth angle information; An interpolation dataset construction module, used to determine the size of the interpolation dataset and construct the interpolation dataset; An interpolation fitting module is used to traverse all azimuth points at each pitch angle and all pitch angle points at each azimuth in the interpolation data set, perform interpolation calculation and curve fitting based on the interpolation polynomial using an interpolation method, and obtain fitting curves for all azimuths and pitch angles in the entire airspace; The amplitude and phase error reconstruction module is used to reconstruct the amplitude error correction value and phase error correction value between each channel of the array antenna and the reference channel at all azimuth and elevation angles in the entire airspace based on the fitting curve of all azimuth and elevation angles in the entire airspace; The interpolation dataset construction module includes: The interpolation interval and point number determination submodule is used to determine the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval according to the non-circularity of the pattern of the array antenna at different elevation angles; A first interpolation data set generation submodule is configured to interpolate all azimuth angles row by row based on each pitch angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval to generate an interpolation data set; and, The second interpolation data set generation submodule is used to interpolate all pitch angles in columns based on each azimuth angle according to the number of interpolation intervals of the interpolation data set and the number of data points contained in each interpolation interval to generate an interpolation data set.

8. An electronic device, characterized in that: comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; The memory is used to store computer programs; The processor is configured to implement the satellite navigation array antenna amplitude and phase calibration method according to any one of claims 1 to 6 when executing the program stored in the memory.

9. One or more computer-readable media having instructions stored thereon, which, when executed by one or more processors, cause the processors to perform the satellite navigation array antenna amplitude and phase calibration method according to any one of claims 1 to 6.

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