Ground station antenna pointing error compensation method and related equipment

Abstract

The invention discloses a ground station antenna pointing error compensation method and related equipment. The method comprises the following steps: controlling an antenna driving shaft to sequentially rotate to a plurality of measuring points according to a preset angle step length in a preset angle range, and synchronously acquiring a command angle value output by an encoder and an actual angle value output by a gradienter at each measuring point; for each measurement point, an error value is calculated according to the relation that the error value is equal to the difference between the actual angle value and the command angle value, and an error sample set containing a plurality of data pairs is formed; and performing curve fitting processing on the error sample set to obtain a continuous and smooth error compensation function in the preset angle range, and performing ground station antenna pointing error compensation by using the error compensation function, the error compensation function being used for representing a mapping relationship between a command angle value and an error value. The problem that an existing ground station antenna pointing error compensation method is high in cost, complex in implementation or limited in compensation effect can be solved.

Description

Technical Field

[0001] This application relates to the aerospace field, and more specifically, to a ground station antenna pointing error compensation method and related equipment. Background Technology

[0002] Ground station antennas are widely used in satellite communications, weather monitoring, and military radar, and their pointing accuracy directly affects the quality of signal reception and transmission. Antenna pointing is typically achieved by rotating a motor-driven shaft, with the shaft's angular position read by an encoder. However, due to factors such as encoder installation errors, mechanical wear, and temperature variations, the encoder readings may deviate from the actual antenna angle, resulting in pointing errors. These errors degrade system performance, especially in applications requiring high-precision tracking. Therefore, effectively compensating for encoder errors and improving antenna pointing accuracy has become a significant technical challenge in this field.

[0003] Traditional methods include mechanical calibration, using high-precision encoders, or employing software lookup tables or linear interpolation for compensation. However, these methods are often costly, complex to implement, or have limited compensation effectiveness. For example, mechanical calibration requires frequent adjustments, while high-precision encoders increase system costs. Software compensation typically relies on simple error lookup tables or linear interpolation, but it cannot fully cover nonlinear errors, resulting in insufficient compensation. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] To address the problems of high cost, complex implementation, or limited compensation effectiveness associated with mechanical calibration, high-precision encoders, or software lookup tables or linear interpolation methods, this invention proposes a ground station antenna pointing error compensation method, which includes: The antenna drive shaft is controlled to rotate sequentially to multiple measurement points within a preset angle range and in preset angle steps. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are synchronously acquired. The level is arranged on the reference surface of the antenna drive shaft. For each measurement point, the error value is calculated based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, forming an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value; Curve fitting is performed on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range. The error compensation function is used to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

[0006] Optionally, the step of using the error compensation function to perform ground station antenna pointing error compensation includes: The error compensation function is integrated into the control program of the programmable logic controller (PLC) so that during the real-time antenna control process, the PLC reads the current command angle value of the encoder and inputs the error compensation function to calculate the current compensation error value. The compensated angle is generated based on the relationship that the compensated angle is equal to the sum of the command angle value and the current compensation error value. The compensated angle is used as the angle basis for antenna pointing control to reduce the deviation between the encoder reading and the actual angle and improve the antenna pointing accuracy.

[0007] Optionally, the preset angle range is -90° to +90°, the preset angle step is 5°, and the method further includes: Before acquiring the commanded angle value and the actual angle value, a preset dwell time is maintained at each measurement point to attenuate the mechanical vibration of the antenna drive shaft and stabilize the level reading.

[0008] Optionally, performing curve fitting processing on the error sample set includes: The fitting method employs at least one of polynomial fitting or Fourier series fitting based on trigonometric functions, and determines the fitting parameters with the goal of minimizing the fitting residual, so that the error compensation function satisfies the continuity and smoothness constraints within the preset angle range.

[0009] Optionally, performing curve fitting processing on the error sample set includes: The preset angle range is divided into multiple angle intervals, and an interval compensation function is obtained by fitting the error sample set in each angle interval. A smooth connection constraint is introduced at the connection point of adjacent angle intervals to make the function values ​​and first derivatives of the compensation functions of each interval continuous at the connection point, so as to reduce the compensation abrupt change caused by interval splicing.

[0010] Optional, also includes: Before integrating the error compensation function into the PLC control program, the command angle values ​​of multiple verification measurement points are input into the error compensation function to obtain the predicted compensation error value, which is then compared with the actual error value of the corresponding verification measurement point. If the comparison result meets the preset error threshold condition, the error compensation function is solidified into a function expression or parameter table in the PLC for real-time compensation.

[0011] Secondly, the present invention also proposes a ground station antenna pointing error compensation device, comprising: The acquisition unit is used to control the antenna drive shaft to rotate sequentially to multiple measurement points within a preset angle range and at a preset angle step size. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are acquired synchronously. The level is arranged on the reference surface of the antenna drive shaft. The calculation unit is used to calculate the error value for each measurement point based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, forming an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value; The compensation unit is used to perform curve fitting processing on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range, so as to use the error compensation function to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

[0012] Thirdly, an electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program stored in the memory to implement the steps of the ground station antenna pointing error compensation method as described in any of the first aspects above.

[0013] Fourthly, the present invention also proposes a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the ground station antenna pointing error compensation method of any of the above claims in the first aspect.

[0014] In summary, the ground station antenna pointing error compensation method proposed in this application controls the antenna drive shaft to rotate sequentially to multiple measurement points within a preset angle range at preset angle steps. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are simultaneously acquired. The level is arranged on the reference plane of the antenna drive shaft. For each measurement point, the error value is calculated based on the relationship that the error value equals the difference between the actual angle value and the command angle value, forming an error sample set containing multiple data pairs, where each data pair includes the command angle value and the corresponding error value. Curve fitting processing is performed on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range. This error compensation function is then used to compensate for the ground station antenna pointing error, and it characterizes the mapping relationship between the command angle value and the error value. Therefore, by arranging the level on the reference plane of the drive shaft and simultaneously acquiring the actual and command angles, the error samples come from independent measurement links, resulting in higher authenticity and repeatability of the error data. By defining the error as the difference between the actual and command angles, the compensation problem is transformed into a function approximation problem, giving the compensation amount a clear physical meaning and enabling direct real-time correction. A continuous and smooth error compensation function is obtained through curve fitting, enabling compensation to cover the entire angle range and express both nonlinear and periodic errors. This results in a more comprehensive compensation effect compared to discrete lookup tables and linear interpolation. Because the compensation function is continuous and smooth, the compensation value does not exhibit unnecessary abrupt changes with angle variations, thereby reducing the risk of control command jitter and improving tracking stability and pointing consistency. This method primarily achieves compensation through software modeling and parameter fixing, reducing reliance on high-precision encoders or additional hardware, which helps lower system costs and improve engineering adaptability. Attached Figure Description

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic flowchart of a ground station antenna pointing error compensation method provided in an embodiment of this application; Figure 2 A schematic diagram of a ground station antenna pointing error compensation device provided in an embodiment of this application; Figure 3 This is a schematic diagram of a ground station antenna pointing error compensation electronic device provided in an embodiment of this application. Detailed Implementation

[0016] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0017] To address the issues of high cost, complex implementation, or limited compensation effectiveness associated with mechanical calibration, high-precision encoders, or software lookup table or linear interpolation compensation methods, please refer to [link to relevant documentation]. Figure 1 , Figure 1 The flowchart of a ground station antenna pointing error compensation method provided in this application embodiment can be specifically included in steps S110 to S130.

[0018] S110, control the antenna drive shaft to rotate sequentially to multiple measurement points within a preset angle range at preset angle steps, and synchronously collect the command angle value output by the encoder and the actual angle value output by the level at each measurement point. The level is arranged on the reference surface of the antenna drive shaft.

[0019] S120, for each measurement point, calculate the error value based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, and form an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value.

[0020] S130, Perform curve fitting processing on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range, so as to use the error compensation function to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

[0021] It is understandable that the antenna pointing is achieved by the rotation of the drive shaft, and the encoder reads the angular position of the shaft or the equivalent position on the motor side. Due to factors such as encoder zero-point offset, shaft assembly eccentricity, backlash and hysteresis, bearing wear, structural expansion and contraction caused by temperature drift, and encoder resolution quantization, the encoder reading will deviate from the true angle. This deviation often contains three types of components: the first is an approximately constant zero-point offset; the second is a periodic error that varies regularly with the angle, often related to eccentricity and gear transmission errors; and the third is a slowly changing nonlinear term, often related to structural deformation and load changes. After these components are superimposed, the error curve is usually not a straight line, and it is not suitable to cover it with linear interpolation using only a few lookup points. The level's measurement of the tilt angle under gravity can serve as a completely different observation link from the encoder. Encoder errors mainly come from mechanical transmission and installation geometry, while the level reading mainly comes from the angle between the attitude and the direction of gravity. Placing the level on the drive shaft reference plane is essentially equivalent to establishing an external reference measurement for the drive shaft angle, making the true angle a measurable quantity instead of an invisible one. The error data obtained in this way is the direct subtraction of the encoder angle from the true angle, rather than inference through complex astronomical orientation or field measurements. Therefore, the data source is more direct and easier to repeat. Furthermore, considering that the error sample set is a discrete set of points, if only table lookup or point-by-point compensation is used, interpolation between measurement points is necessary. Linear interpolation cannot approximate strong nonlinear terms and is prone to undercompensation or overcompensation in sections of the error curve with large curvature changes. The essence of curve fitting is to approximate discrete samples as a continuous function in the least squares sense. The direct benefits of a continuous function are threefold: First, compensation values ​​can be obtained for any angle, regardless of the table lookup step size; second, the function changes smoothly in the angle domain, which can suppress control jitter caused by abrupt changes in compensation values; third, the fitted model can express periodicity or higher-order nonlinearity, thus covering more complex error patterns.

[0022] For example, to obtain basic data reflecting the deviation between encoder readings and the actual antenna pointing, a level is first placed on a reference surface of the antenna drive shaft. This reference surface is preferably a plane rigidly connected to the drive shaft, with high machining precision, and capable of representing the shaft's attitude, such as the pitch shaft end flange face or the turntable calibration surface. The level can be an electronic level or a tilt sensor to output angle values ​​that can be read by the control system. The command angle value output by the encoder reflects the equivalent rotation angle of the shaft system or motor side, while the actual angle value output by the level reflects the tilt angle of the reference surface relative to the direction of gravity. These two values ​​belong to different measurement links, avoiding the problem of invisible errors caused by relying solely on encoder self-measurement. Subsequently, the control antenna drive shaft rotates sequentially to multiple measurement points within a preset angle range and with a preset angle step size. The preset angle range can be set to -90° to +90°, and the preset angle step size can be set to 5° or smaller to meet higher accuracy requirements. After reaching each measurement point, a preset dwell time is maintained to wait for mechanical vibration to decay and the reading to stabilize. Within the dwell window, the encoder command angle value and the actual angle value of the level are synchronously sampled. The synchronous sampling can be achieved by reading two types of data in the same sampling period and taking the average, or by triggering a sampling when the level reading changes less than a threshold within several consecutive sampling periods, thereby ensuring that the two types of angle data are paired consistently under the same mechanical posture. Through the above method, the collected data has good coverage and repeatability across the entire angle range, effectively reducing data offset caused by transient vibration, inconsistent sampling times, or human reading errors, thus providing stable samples for subsequent error calculation and curve fitting. For example, if the structure is subjected to stress near -30°, causing slight deflection changes, sufficient dwell and averaging can significantly reduce random fluctuations in this area, making subsequent fitting more accurate in characterizing the systematic deviation of this area.

[0023] For example, after synchronously acquiring the command angle value and the actual angle value at each measurement point, an error value is calculated for each measurement point based on the relationship that the error value equals the difference between the actual angle value and the command angle value. This forms an error sample set containing multiple data pairs. Each data pair includes at least the command angle value and its corresponding error value, and may further include fields such as measurement point number, sampling timestamp, level reading fluctuation amplitude during the dwell period, and movement direction identifier. The error is defined as the deviation of the true angle from the command angle. If this deviation can be calculated from the command angle value and corrected subsequently, the compensated angle can be made closer to the true angle. Therefore, constructing an error sample set by subtracting the command angle from the actual angle can directly establish a mapping relationship between the command angle and the compensation amount. To improve the reliability of the sample set and the noise resistance of the fitting, stability screening or outlier handling mechanisms can be introduced when constructing the sample set. For example, if the level reading fluctuates beyond a preset threshold during the dwell period of a certain measuring point, the sample at that measuring point is marked as an unstable sample and removed, or its weight in subsequent fitting is reduced. Another example is the reasonableness detection of the error difference between adjacent measuring points. If the error at a certain point shows a discontinuous abrupt change compared to adjacent points, and the corresponding dwell fluctuation is also abnormal, then that point is determined to be an outlier, possibly affected by external force or mechanical impact. The error sample set formed in the above way can more comprehensively reflect the systematic error patterns caused by factors such as encoder installation offset, shaft eccentricity, backlash and hysteresis, and structural expansion and contraction due to temperature changes, and reduce the interference of random noise on the model, thereby improving compensation stability and transferability. For example, if a short-term vibration occurs at a 30° measuring point, causing the level reading to momentarily increase, fluctuation threshold screening can prevent this point from pulling the fitting curve into a local bulge, thus preventing the compensation function from overcompensating in that interval and causing pointing jitter.

[0024] For example, the error sample set is input into a calculation tool to perform curve fitting processing, resulting in a continuous and smooth error compensation function within the preset angle range. This error compensation function characterizes the mapping relationship between the command angle value and the error value, and is used for ground station antenna pointing error compensation. The error sample set consists of discrete measurement points, and the command angle value changes continuously during actual operation. Therefore, a continuous function capable of outputting the corresponding compensation error for any command angle value is needed. Simultaneously, mechanical errors typically contain nonlinear and periodic terms. Simply relying on discrete lookup tables or linear interpolation can easily lead to insufficient or excessive compensation in curvature variation regions. Curve fitting, on the other hand, can approximate the error pattern globally and provide a smooth output. The fitting model can be selected based on the error morphology: if the error exhibits a slow, nonlinear trend with changing angle, polynomial fitting can be used, balancing fitting accuracy and boundary oscillation risk when selecting the order; if the error exhibits a clear periodicity or repetitive waveform, Fourier series fitting based on trigonometric functions can be used to better fit the periodic error mechanism; when the variation intensity of the error varies greatly in different angle segments, piecewise fitting can also be used, dividing the preset angle range into multiple angle intervals and fitting interval compensation functions separately, applying continuous constraints on function values ​​at interval connections, and further applying first-order continuous constraints on the rate of change if necessary to avoid abrupt compensation changes at the connections. After fitting, additional verification points or intermediate angles between measurement points can be used for verification to ensure that the fitting residuals meet the preset threshold, and the fitted function expression and its parameters are solidified in an executable form for the control system to call; during actual compensation, the controller reads the encoder command angle value and substitutes it into the error compensation function to obtain the compensation error, and superimposes the compensation error with the command angle to obtain the compensated angle, making the compensated angle statistically close to the actual angle measured by the level. By using a continuous and smooth compensation function, stable compensation values ​​can be output across the entire angle range, reducing residual pointing deviations caused by interpolation errors between discrete compensation points and mitigating the impact of sudden changes in compensation values ​​on servo control stability, thereby improving antenna pointing accuracy and tracking stability. For example, when the error has a peak and valley every 30°, Fourier fitting can express this periodic pattern with fewer parameters, allowing the compensation to maintain a smooth transition in the peak and valley range. However, if the error curvature increases near the limit elevation angle, piecewise fitting can improve local approximation accuracy and avoid underfitting of global fitting in this range.

[0025] In some examples, the use of the error compensation function to perform ground station antenna pointing error compensation includes: The error compensation function is integrated into the control program of the programmable logic controller (PLC) so that during the real-time antenna control process, the PLC reads the current command angle value of the encoder and inputs the error compensation function to calculate the current compensation error value. The compensated angle is generated based on the relationship that the compensated angle is equal to the sum of the command angle value and the current compensation error value. The compensated angle is used as the angle basis for antenna pointing control to reduce the deviation between the encoder reading and the actual angle and improve the antenna pointing accuracy.

[0026] For example, in order to enable the error compensation law obtained from offline calibration to play a real-time role during antenna operation, the error compensation function is integrated into the control program of the programmable logic controller (PLC) in an executable form. The current command angle value output by the encoder is a state quantity that the real-time control system can stably acquire. The error compensation function can output the corresponding compensation error value by taking this command angle value as input, thereby solidifying the mapping relationship from command angle to error into a calculation process that the control system can directly call, avoiding the introduction of step abrupt changes and interpolation deviations between measurement points by manual table lookup or discrete point interpolation. In practical implementation, the model parameters of the error compensation function can be written into the data block or register area of ​​the PLC. For example, when the error compensation function is a polynomial fitting result, the coefficients of each order are stored and the compensation error is calculated by polynomial evaluation in each control cycle. When the error compensation function is a fitting result based on trigonometric functions, the coefficients of each harmonic term are stored and the corresponding sine and cosine terms are calculated in the PLC and then weighted to obtain the compensation error. When piecewise fitting is used, the parameter sets corresponding to each angle interval are stored separately, and the corresponding parameter set is selected in the PLC according to the interval to which the current command angle value belongs to obtain the compensation error. Furthermore, a transition angle band can be set near the interval boundary. Within the transition angle band, the outputs of two adjacent function segments are smoothly merged according to weights to reduce the risk of minor discontinuities caused by function switching. To ensure real-time performance and reading stability, the PLC can use a sampling period consistent with the servo interpolation period when reading the current command angle value from the encoder. It can also apply a light stabilization process to the angle input, such as averaging angle samples within a short time window without introducing significant phase lag, or temporarily suspending the update of the compensation error value when the detected angle micro-vibration amplitude exceeds a threshold, thus avoiding amplifying high-frequency noise into compensation jitter. Through this integrated and real-time calculation method, the compensation error value can be continuously updated with the current angle position, resulting in smoother compensation output with angle changes. This reduces the excitation of the servo system by abrupt commands caused by discrete compensation, thereby improving the stability and repeatability of compensation across the entire angle range. For example, during satellite tracking, when the antenna needs to be rapidly corrected, the compensation error value calculated by the continuous function is adjusted synchronously with small angle changes, significantly reducing the risk of micro-vibration caused by step changes in the compensation value and improving the pointing consistency during tracking. After the PLC obtains the current compensation error value, it generates the compensated angle based on the relationship that the compensated angle is equal to the sum of the command angle value and the current compensation error value. The compensated angle is then used as the angle basis for antenna pointing control. The error is defined as the difference between the actual angle value and the command angle value. Adding this error to the command angle value yields an equivalent angle that is closer to the actual angle. Therefore, when the compensation error value is approximated by the fitting function to approximate the true error, the remaining deviation between the compensated angle and the actual angle is mainly determined by the fitting residual and random disturbances, which is usually significantly smaller than the systematic deviation when uncompensated.In practical implementation, the PLC can use the compensated angle in one of two control paths: firstly, the compensated angle can be used as an equivalent angle quantity on the feedback side to participate in position control calculations, allowing the controller to use angle feedback closer to the actual posture to calculate the control quantity, thereby reducing steady-state deviation; secondly, the compensated angle can be used as the target angle or interpolation angle on the command side to send to the driver, making the mechanical posture after the driver execution closer to the desired direction. To improve engineering safety and robustness, an effective domain and limiting strategy can be set when generating the compensated angle. For example, when the command angle value exceeds the calibrated angle range, a boundary-preserving compensation output can be used, or a maximum absolute value limit can be set for the compensation error value to prevent overcompensation caused by abnormal parameters. At the same time, the difference between the compensated angle and the command angle can be recorded for operation status monitoring and maintenance diagnosis. By using the compensated angle as the control basis, systematic pointing errors caused by factors such as encoder installation offset, shaft eccentricity, backlash, and temperature drift can be reduced across the entire angle range. This reduces the mean and peak values ​​of antenna pointing errors and improves pointing consistency across different angle ranges. For example, if the original system has a fixed directional deviation in a certain elevation angle range, causing the beam center to deviate from the target, the compensated angle can compress the pointing deviation in that range to the level of the fitting residual, thereby improving the received signal level and link margin. Another example is that in meteorological scanning tasks, it is necessary to repeatedly scan the same angular trajectory. The compensated angle can reduce the systematic offset of repeated positioning, making the spatial registration consistency of multiple scanning results higher, thereby improving the subsequent data fusion and imaging quality.

[0027] In some examples, the preset angle range is -90° to +90°, the preset angle step size is 5°, and the method further includes: Before acquiring the commanded angle value and the actual angle value, a preset dwell time is maintained at each measurement point to attenuate the mechanical vibration of the antenna drive shaft and stabilize the level reading.

[0028] For example, to improve the reliability and repeatability of the command angle values ​​and actual angle values ​​collected at each measurement point, a preset dwell time is maintained at each measurement point before collecting the command angle values ​​and actual angle values. This allows the mechanical vibration of the antenna drive shaft to decay and the level reading to stabilize. During the process of the antenna drive shaft moving from the previous measurement point to the current measurement point, factors such as motor acceleration and deceleration, elastic deformation release of the transmission chain, adjustment of tooth backlash contact state, and inertial swing of the antenna structure will introduce short-term mechanical vibration and micro-oscillation of attitude. At this time, the command angle value output by the encoder may have reached the target position, but the actual mechanical attitude is still in the decay oscillation stage. At the same time, as a tilt measurement device based on the direction of gravity, the level is sensitive to small angular velocities and structural swing. If sampling is performed before the vibration has decayed, transient oscillation will be mistaken for systematic error, resulting in the subsequent error sample set containing transient time components that are independent of the angle position. This will cause the fitted error compensation function to have local fluctuations or overfitting and introduce unnecessary compensation jitter in real-time compensation. In specific implementation, the preset dwell time can be set comprehensively based on the antenna structure inertia, deceleration ratio, servo adjustment time, and level response time. For example, it can be set to 1 to 5 seconds, or a longer dwell time can be adaptively set according to different angle segments to adapt to more obvious structural sway when approaching the extreme elevation angle. Furthermore, stability criteria can be introduced during the dwell period to more accurately determine the sampling timing. The stability criteria may include the maximum change amplitude of the level reading in multiple consecutive sampling cycles being lower than a threshold, the short window standard deviation of the level reading being lower than a threshold, the encoder angle change rate being lower than a threshold, or the servo drive maintaining the "in position" state for more than a threshold duration. After the stability criteria are met, the synchronous acquisition of the command angle value and the actual angle value is triggered, or multiple samplings of the two types of angle readings are performed within the dwell window and the average value is taken as the representative value of the measurement point, thereby reducing the influence of random fluctuations and transient swings. By employing the aforementioned dwell stabilization measures, measurement noise introduced by motion transition states can be significantly reduced. This allows error samples to more effectively reflect the systematic deviation patterns caused by encoder installation bias, shaft eccentricity, backlash, and temperature drift. Consequently, the smoothness and generalization ability of the curve fitting compensation function are improved, reducing the probability of unreasonable abrupt changes in the compensation function between adjacent angles. Ultimately, this enhances the pointing accuracy and tracking stability of the antenna across the entire angle range. For example, if there is a slight sway in the structure when the antenna rotates from 25° to 30°, direct sampling without dwell may result in an overestimated actual angle reading and an abnormally large error at that measurement point. After fitting, a local bulge will form near 30°, causing overcompensation when the antenna crosses this interval during operation. However, by using dwell and sampling after the stability criterion is met, the error at that measurement point returns to the true systematic deviation level, resulting in a smoother fitting curve and a more stable compensation output.

[0029] In some examples, performing curve fitting on the error sample set includes: The fitting method employs at least one of polynomial fitting or Fourier series fitting based on trigonometric functions, and determines the fitting parameters with the goal of minimizing the fitting residual, so that the error compensation function satisfies the continuity and smoothness constraints within the preset angle range.

[0030] For example, to transform the error sample set at discrete measurement points into an error compensation function that can be continuously invoked during real-time antenna control, curve fitting is performed on the error sample set. This curve fitting process employs at least one fitting method, either polynomial fitting or Fourier series fitting based on trigonometric functions. The fitting parameters are determined with the goal of minimizing the fitting residual, ensuring that the error compensation function satisfies continuity and smoothness constraints within the preset angle range. The error sample set consists of multiple data pairs, where the independent variable of each pair is the command angle value, and the dependent variable is the corresponding error value. However, the command angle value changes continuously within the preset angle range during actual antenna operation. Relying solely on discrete lookup tables or simple linear interpolation can easily lead to insufficient or excessive compensation in sections where the error curve exhibits significant bending or periodic fluctuations. Furthermore, piecewise linear broken lines are formed between measurement points, resulting in insufficiently smooth changes in the compensation value. By approximating the error data as a continuous function in an overall sense through fitting, the compensation error can be output at any command angle, and the compensation error remains smooth with angle changes, making it more suitable for real-time use in servo control. In practical implementation, when the error exhibits a slow, nonlinear trend with respect to angle, such as gradual errors caused by structural micro-deformation, installation offset, or temperature leading to a monotonic or slowly curving error curve, polynomial fitting is preferred. By setting the polynomial order and solving for the coefficients of each order, the sum of squared residuals between the predicted and measured errors at each measuring point is minimized. Furthermore, the selection of the order balances fitting accuracy and function smoothness, ensuring the fitted curve avoids unreasonable and drastic fluctuations within a preset angle range. When the error exhibits an approximately periodic or repetitive waveform with respect to angle, such as peak-and-valley repetitive patterns caused by shaft eccentricity, transmission errors, or periodic assembly errors, a polynomial fitting method is preferred. Fourier series fitting uses a linear combination of sine and cosine terms to represent the error variation with angle. By determining the coefficients of each harmonic term, the fitting residual is minimized. Overfitting to measurement noise is suppressed by limiting the harmonic order or imposing constraints on higher-order terms, thus maintaining the ability to express periodic errors while satisfying continuity and smoothness constraints. After fitting, the continuity and smoothness of the error compensation function can be checked within a preset angle range. For example, it can be checked whether the change in the function output under adjacent angle increments is smooth, and whether the maximum value and mean square value of the fitting residual are within an acceptable range, to ensure that the function does not produce abrupt compensation amounts in real-time compensation.By using the parameter determination method described above, which aims to minimize the fitting residual, the error compensation function can stably approximate the systematic error pattern across the entire angle range. This allows the compensation output to have a continuous response to angle changes and reduces the step component of the compensation command, thereby reducing the risk of control jitter introduced by compensation and improving pointing consistency. For example, if the error exhibits a recurring peak-valley structure around every 30°, Fourier series fitting can obtain a continuous and smooth compensation curve with fewer parameters. This allows the compensation error output in the peak-valley interval to change gradually with the angle rather than abruptly jumping, making it easier to maintain stable servo tracking when traversing this interval. If the overall error shows a slow, curved upward trend, polynomial fitting can output a smooth compensation curve across the entire range, ensuring that the remaining pointing error at each angle point is mainly determined by the fitting residual and is significantly smaller than the systematic deviation when uncompensated.

[0031] In some examples, performing curve fitting on the error sample set includes: The preset angle range is divided into multiple angle intervals, and an interval compensation function is obtained by fitting the error sample set in each angle interval. A smooth connection constraint is introduced at the connection point of adjacent angle intervals to make the function values ​​and first derivatives of the compensation functions of each interval continuous at the connection point, so as to reduce the compensation abrupt change caused by interval splicing.

[0032] For example, to balance local accuracy and smoothness of compensation output across the entire angle range, a piecewise fitting method is used when performing curve fitting on the error sample set. Specifically, this involves dividing the preset angle range into multiple angle intervals and fitting the corresponding interval compensation function to the error sample set within each angle interval. The sources of error in the antenna drive shaft may exhibit different dominant mechanisms and intensity of change in different angle segments. For instance, in the middle angle segment, the error may be mainly caused by installation zero-position offset and slight eccentricity, resulting in slow changes. However, in the segment near the limit elevation or depression angle, the error may exhibit more significant nonlinearity due to changes in structural stress state, increased deflection, or changes in transmission load. This leads to the sacrifice of local segment approximation accuracy when using a single global function in order to minimize the global residual. By segmenting the angle range and fitting independently within each segment, function parameters more suitable for the shape of the segment can be selected in segments with drastic error changes, resulting in smaller fitting residuals in those segments. At the same time, a simpler function shape is maintained in segments with gentle error changes to avoid overfitting noise. In practice, the angle intervals can be divided uniformly according to a preset step size, such as dividing each interval into 30° intervals, or non-uniformly according to the changing characteristics of the error curve, such as using shorter intervals in sections with larger error curvature to improve local fitting ability. The fitting method within each interval can be polynomial fitting or trigonometric function-based fitting, and the parameters are determined within the interval with the goal of minimizing the fitting residual. To avoid compensation jumps at interval boundaries caused by piecewise fitting, which could lead to step excitation in the servo control, a smooth connection constraint is introduced at the junction of adjacent angle intervals. This ensures that the function values ​​and first derivatives of the compensation functions for each interval are continuous at the junction. The continuity of function values ​​ensures that the compensation error does not change abruptly at the boundary angle, and the continuity of the first derivative ensures that the rate of change of the compensation error with respect to the angle does not change abruptly at the boundary. This results in a smooth transition of the compensated angle when crossing interval boundaries. In engineering implementation, the continuity condition at the junction can be added as a constraint to the parameter solution process during fitting, or a shared junction point can be set at the junction and equality constraints can be applied to the junction point values ​​of the functions of adjacent intervals and the rate of change at the junction point. Additionally, a small number of overlapping measurement points can be set on both sides of the junction to enhance the stability of the constraints.By employing the aforementioned piecewise fitting and introducing smooth connection constraints based on continuous function values ​​and first derivatives, local compensation accuracy can be improved even when errors exhibit regional differences. This significantly reduces the risk of abrupt compensation changes caused by interval splicing, ensuring that the compensation output conforms to the error patterns of each segment while maintaining smoothness with angle variations. Consequently, it reduces the micro-vibrations and overshoots caused by abrupt changes in compensation commands to the servo system and enhances antenna tracking stability. For instance, when the error increases significantly in the segment approaching 80° to 90° but changes gradually near zero°, piecewise fitting allows for more thorough compensation in the extreme segments. Furthermore, the continuity constraints of function values ​​and first derivatives at the connection points prevent sudden changes in compensation from 75° to 80°, which could lead to instantaneous pointing shifts. This results in more consistent pointing accuracy during scanning or tracking tasks.

[0033] In some examples, it also includes: Before integrating the error compensation function into the PLC control program, the command angle values ​​of multiple verification measurement points are input into the error compensation function to obtain the predicted compensation error value, which is then compared with the actual error value of the corresponding verification measurement point. If the comparison result meets the preset error threshold condition, the error compensation function is solidified into a function expression or parameter table in the PLC for real-time compensation.

[0034] For example, to avoid insufficient or excessive compensation, or unreasonable fluctuations in local angle segments, the error compensation function obtained through fitting may not be fully compensated during actual operation. Before integrating the error compensation function into the PLC control program, the function is verified and then fixed to the PLC after successful verification. The error compensation function is an approximate model fitted based on an error sample set. The fitting process may be affected by measurement noise, uneven sample distribution, or limitations in the model's expressive power, resulting in larger fitting residuals in certain angle segments. If deployed directly to the PLC without verification, the local deviation of the compensation function may be continuously amplified by real-time control, causing systematic shifts in antenna pointing in certain angle segments or micro-vibrations during the tracking process. Therefore, it is necessary to perform consistency checks on the fitting results using independent or densely sampled verification measurement points before deployment. In specific implementation, multiple verification measurement points can be selected within a preset angle range. These verification measurement points can be intermediate angle points between the original measurement points or more densely packed angle points within the commonly used working elevation angle range of the antenna. At each verification measurement point, command angle values ​​and actual angle values ​​are acquired using the same acquisition method as in the modeling stage to calculate the actual error value of that verification measurement point. Then, the command angle values ​​of multiple verification measurement points are input into the error compensation function to obtain a predicted compensation error value. This predicted compensation error value is then compared with the actual error value of the corresponding verification measurement point. The comparison indicators may include absolute error, maximum absolute error, mean square error, or weighted error in key angle ranges. The preset error threshold condition can be set to at least one of maximum absolute deviation not exceeding a threshold and mean square deviation not exceeding a threshold, and the threshold value can be determined based on antenna pointing accuracy indicators, beamwidth, or link budget margin. When the comparison result meets the preset error threshold condition, the error compensation function is solidified into a function expression or parameter table in the PLC for real-time compensation. The solidification method can be writing the coefficient parameters of a polynomial or Fourier series into the PLC. The data block is evaluated by expression at runtime, or the compensation function is discretized into a parameter table on a high-resolution angle grid and called in the PLC by interpolation, so as to maintain compensation accuracy while meeting real-time requirements; when the comparison result does not meet the preset error threshold condition, the fitting model type, fitting order, segmented interval division or measurement point weight can be readjusted and refitted, and the verification process can be executed again until the threshold condition is met.Through the above verification and solidification steps, local distortions in the compensation function caused by sample noise or model mismatch can be screened out before deployment. This ensures that the compensation function finally written into the PLC has a controllable maximum error and stable output characteristics across the entire angle range, thereby reducing the risk of angle segment deviations after deployment and improving the pointing reliability of the antenna during long-term operation. For example, when the error changes smoothly near zero degrees but the error curvature increases near 70 degrees, the verification measurement point can reveal whether the fitted function is underfitting near 70 degrees and causing the residual to exceed the threshold. Only when the residual in this segment is controlled within the threshold is the function solidified into the PLC, thus ensuring that satellite tracking or scanning tasks can maintain stable pointing accuracy in critical working elevation angle segments.

[0035] In some cases, considering that antenna drive shafts typically include mechanisms such as reducers, gear drives, or worm gear drives, the contact surface state of the drive shaft at a given commanded angle will be related to the direction of motion when backlash and elastic deformation exist in the transmission chain. During forward approach, the tooth surface is stressed and engaged on one side; during reverse approach, the tooth surface is stressed and engaged on the other side, and the actual angle may lag or lead after the backlash reversal process. This means that the actual angle corresponding to the same commanded angle value is not unique, but rather there are at least two repeatable error curves, corresponding to forward and reverse arrival respectively. If a single error compensation function is still used, the two curves will be forcibly compromised, resulting in residual system biases in both forward and reverse tracking. Especially when frequent fine-tuning is performed in satellite tracking, this residual bias will manifest as inconsistent pointing errors with direction switching. Based on this, some examples also include: When forming the error sample set, the command angle value and the actual angle value are collected and the error value is calculated when the antenna drive shaft reaches the measurement point in both the forward and reverse directions to obtain a forward error sample set and a reverse error sample set. A forward error compensation function and a reverse error compensation function are respectively fitted to the forward error sample set and the reverse error sample set. During the real-time antenna control process, the PLC selects the forward error compensation function or the reverse error compensation function according to the direction of change of the command angle value to calculate the current compensation error value.

[0036] Understandably, during calibration sampling, in addition to recording the commanded angle value and the actual angle value of the level, the arrival direction marker is also recorded. The arrival direction marker can be determined by the angle sequence direction of adjacent sampling points; for example, when the commanded angle increases from a smaller value to the current point, it is marked as positive, and when it decreases from a larger value to the current point, it is marked as negative. Sampling is performed on each measurement point under both positive and negative arrival conditions, and the error values ​​are calculated to form a positive error sample set and a negative error sample set. To enhance repeatability, it is recommended that each direction be sampled at least once, and the errors from repeated sampling be averaged or weighted according to stability. Curve fitting is then performed on the positive and negative error sample sets respectively to obtain the positive error compensation function and the negative error compensation function. The fitting form can follow the aforementioned polynomial or Fourier series, or piecewise fitting can be used, but the key is that the two functions approximate the error patterns under their respective directions. During real-time control, the PLC reads the current command angle value from the encoder and determines the current direction of motion based on the change direction of the command angle value in adjacent control cycles. It then selects the corresponding compensation function to calculate the compensation error value and generates the compensated angle. During direction switching, a difference in compensation error can easily occur when switching from the output of the forward function to the output of the reverse function. To avoid abrupt changes in compensation, a transition angle band can be set. For example, the outputs of the two functions can be smoothly weighted within a small range centered on the reversal point, allowing the compensation error to change continuously near the reversal point.

[0037] In some cases, the torsional elastic deformation of the drive train can alter the mapping from the command angle to the actual angle due to variations in wind load, gravitational moment, inertia, or structural drag. Motor current or servo torque estimates are available signals reflecting the current load condition. At the same command angle, as the load increases, the torsional deformation of the drive train increases, and the deviation of the actual angle from the command angle changes accordingly. This error is not a purely geometric constant, nor a simple function of angle, but rather an error determined by both the angle and the load. Incorporating load information into the compensation makes the compensation function adaptable to changes in wind load and gravitational moment, which is difficult to cover with conventional univariate fitting. Based on this, some examples also include: During the formation of the error sample set or in the real-time antenna control process, the motor current value or torque estimate that characterizes the antenna-driven load is obtained, and the error sample set corresponding to the preset angle range is divided into multiple load interval error subsets according to the motor current value or torque estimate. Multiple load-related error compensation functions corresponding to the load interval are fitted respectively. During the real-time antenna control process, the PLC selects the corresponding load-related error compensation function according to the load interval to which the current motor current value or torque estimate belongs to calculate the current compensation error value.

[0038] Understandably, the estimated motor current or torque is read from the servo drive or PLC communication, and then subjected to unit unification and filtering. The filtering aims to remove short-term spikes without introducing significant hysteresis; short-window averaging or amplitude-limiting smoothing can be used. Based on historical data or equipment specifications, the load signal is divided into multiple intervals, such as low load, medium load, and high load. The interval boundaries can be determined based on current quantiles, torque rated proportions, or statistical distribution under typical wind speeds. During sampling, the synchronized command angle, actual angle, and estimated current or torque value are recorded at each measuring point. Error samples are grouped according to load intervals, resulting in multiple load-related error sample subsets. To ensure that each subset covers a sufficient angle range, sampling can be arranged under different wind conditions, different antenna attitudes, or different counterweight states. The corresponding load-related error compensation function is fitted to each load interval error sample subset, and the function parameters for each interval are written into the PLC data block. During real-time control, the PLC reads the current load signal, determines the interval it belongs to, selects the corresponding compensation function, and outputs the compensation error. To avoid frequent switching caused by load signal jitter near the interval boundaries, a hysteresis threshold can be set or an interval transition band can be introduced. Within the transition band, the function outputs of adjacent intervals can be weighted and fused. During wind gusts or sudden load changes, the compensation error may change rapidly. An upper limit can be set on the rate of change of the compensation error to prevent abrupt changes in the compensation angle within the control cycle.

[0039] In some cases, the impact of temperature on a structure is considered to stem not only from the average temperature but also from temperature gradients. Sunlight, shading, or internal heat sources within the equipment can create temperature differences across the reference surface and between its upper and lower sections, causing structural warping or uneven thermal expansion of bearing housings, leading to changes in the error curve shape. Using only a single ambient temperature as the basis for compensation often fails to detect local error changes caused by the gradient. Constructing a temperature gradient index using at least two temperature sampling points transforms the difficult-to-observe thermal deformation state into a quantifiable indicator, making the compensation sensitive to thermal warping. Based on this, some examples also include: Before forming the error sample set or integrating the error compensation function into the PLC control program, the temperature values ​​of at least two temperature sampling points corresponding to the antenna drive shaft reference surface are obtained, and a temperature gradient index is determined based on the temperature difference between the at least two temperature sampling points. The output compensation error value of the error compensation function is corrected for temperature gradient according to the temperature gradient index, or the error sample set is grouped according to the temperature gradient index and fitted to obtain multiple temperature gradient-related error compensation functions, so that the compensation error value is adaptively adjusted with the temperature gradient.

[0040] Understandably, at least two temperature sampling points can be arranged near the drive shaft reference surface or the bearing housing, preferably at locations where the thermal gradient may be significant, such as the left and right ends or the top and bottom of the reference surface. The sensors can be thermistors or digital temperature probes. The PLC or host computer calculates the temperature difference as a temperature gradient indicator. Further filtering of the temperature difference can be applied to avoid transient noise affecting the compensation. Error samples can be grouped according to the temperature gradient, and compensation functions can be fitted separately at different gradient levels to obtain multiple temperature gradient-related error compensation functions. During operation, the function is selected based on the current gradient or interpolation is performed. Alternatively, a reference temperature compensation function can be fitted first, followed by the temperature gradient sensitivity coefficient to the error, and gradient correction of the compensation error can be performed in the PLC. The correction amount can be proportional to the temperature gradient or determined according to a piecewise linear relationship. When the temperature gradient exceeds the calibration coverage range, boundary preservation or conservative correction is used to avoid extrapolation leading to compensation distortion.

[0041] In some cases, considering that calibration is typically performed under slow arrival and long dwell conditions, the resulting error is quasi-static. In actual operation, the antenna may track the target at a high angular velocity, and the structure experiences inertial sway, control lag, and elastic deformation, causing the error to be related not only to the angle but also to the arrival velocity or motion state. At the same angular position, the higher the velocity, the more pronounced the dynamic deviation may be. If purely static function compensation is still used, residual errors will occur during rapid tracking, manifesting as pointing lag or overshoot. Based on this, some examples also include: When forming the error sample set, the command angle value and the actual angle value are collected for at least some measurement points under different positioning angular velocities or different interpolation speed settings, and the error value is calculated to obtain multiple speed condition error sample subsets corresponding to the angular velocity or interpolation speed settings; multiple speed-related error compensation functions are obtained by fitting the multiple speed condition error sample subsets respectively, or the compensation error value output by the error compensation function is dynamically corrected in the PLC based on the angular velocity or acceleration corresponding to the command angle value.

[0042] Understandably, during calibration and operation, angular velocity setpoints, interpolated speed setpoints, or speed feedback values ​​are read from the driver; angular acceleration is calculated when necessary. During calibration sampling, for the same angular measurement point, the command angle and actual angle are sampled under different arrival speed settings, and the error is calculated, forming multiple speed condition error sample subsets, such as low-speed condition sample sets and high-speed condition sample sets. Speed-related error compensation functions can be fitted to each speed condition sample subset separately, and the function is selected according to the current speed condition during operation. Alternatively, the fitted static compensation function can be used as a basis, and then a speed or acceleration correction term for the error can be fitted, with a dynamic correction amount superimposed on the static compensation error in the PLC. Limits and rate of change limits are set for the dynamic correction amount, and the speed signal is moderately smoothed to avoid compensation jitter caused by speed measurement noise. When the speed approaches zero, it automatically degenerates into static compensation to avoid introducing unnecessary dynamic correction in a static state.

[0043] In some cases, considering that the periodic errors of a transmission system are often related to the number of gear teeth and the worm gear transmission ratio, the errors exhibit a specific period in the angular domain. Conventional Fourier fitting, without constraints, may use higher-order harmonics to fit noise or local outliers, leading to instability of the compensation function at unobserved angles. Associating the candidate harmonic set with the transmission parameters is equivalent to limiting the fitting degrees of freedom to physically meaningful periodic components, making the model more robust, interpretable, and less prone to overfitting. Based on this, some examples also include: When performing curve fitting on the error sample set, a candidate harmonic set is determined based on the number of transmission teeth or transmission ratio of the antenna drive shaft. When using Fourier series fitting based on trigonometric functions, the fitting term is restricted to the harmonic terms in the candidate harmonic set, or the harmonic terms in the candidate harmonic set are given a higher fitting weight than the non-candidate harmonic terms, so that the error compensation function preferentially characterizes the periodic error component related to the transmission period.

[0044] Understandably, this involves obtaining parameters such as the reducer's transmission ratio, the number of gear teeth, or the number of worm threads, and calculating the correspondence between the command angle change and the transmission cycle. Based on the transmission cycle, a set of interpretable harmonic indices is determined; for example, a fundamental frequency corresponds to one transmission cycle, and several harmonics are selected as candidate sets. When performing Fourier series fitting on the error sample set, only harmonic terms from the candidate sets are allowed to participate in the fitting, or higher weights are assigned to the harmonic terms in the candidate sets to prioritize the fitting and explain the transmission cycle error. If the constrained fitting residual still exceeds the threshold, a small number of supplementary terms can be added while maintaining the candidate set as the main component. However, constraints must be applied to the new terms to avoid severe oscillations. The constrained Fourier coefficients are then embedded into the PLC, and compensation errors are calculated based on the constrained harmonic terms during runtime, reducing computational load and improving output stability.

[0045] In some cases, a fixed dwell time does not always guarantee stable readings. Certain angular sections are more sensitive to structural modes, exhibiting low-frequency micro-vibration attenuation tails after reaching a stable position, causing the level reading to oscillate periodically within a small range. If sampling occurs during this oscillation, the transient oscillation may be mistakenly treated as a systematic error, leading to spurious peaks and troughs in the error samples within that section, resulting in unreasonable fluctuations in the fitting compensation function. By statistically analyzing or determining the frequency domain stability of the level data during the dwell period, the determination of whether a steady state has been reached can be transformed from an empirical timeframe into a calculable condition, significantly improving the quality of the sample set. Based on this, some examples also include: Before acquiring the command angle value and the actual angle value, the system stays at each measurement point and performs a stability determination on the actual angle value output by the level during the stay. The stability determination includes calculating the variance or dominant frequency energy of the actual angle value within a preset time window and comparing it with a threshold. Synchronous acquisition of the command angle value and the actual angle value is triggered only when the variance or dominant frequency energy meets the threshold condition, or the stay time is extended or the fitting weight of the error sample of the corresponding measurement point is reduced when the threshold condition is not met.

[0046] For example, after the antenna reaches the measurement point, the actual angle value of the level can be read at a fixed sampling period during the dwell time, forming a short time series. The variance or standard deviation of this short time series is calculated to reflect the fluctuation amplitude; simultaneously, the dominant frequency energy index can be calculated to reflect the presence of significant periodic vibration components. The dominant frequency energy can be achieved by frequency domain transformation of the short series or by using simplified periodic detection. The variance or dominant frequency energy is compared with a threshold. Only when the index meets the threshold condition is the synchronous acquisition of the command angle and the actual angle triggered and used for error calculation. If the threshold condition is not met, the dwell time is extended and detection continues. If some measurement points are difficult to meet the stable threshold for a long time, sampling can still be carried out while reducing their fitting weight, under the premise of ensuring safety, to avoid excessive pulling on the fitting curve by that point. The threshold can be adaptively adjusted according to the angle segment or equipment status; for example, the threshold can be appropriately relaxed under high wind conditions and combined with an averaging strategy to avoid the calibration process becoming unfinishable.

[0047] Please see Figure 2 One embodiment of the ground station antenna pointing error compensation device in this application includes: The acquisition unit 21 is used to control the antenna drive shaft to rotate sequentially to multiple measurement points within a preset angle range and at a preset angle step size. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are acquired synchronously. The level is arranged on the reference surface of the antenna drive shaft. The calculation unit 22 is used to calculate the error value for each measurement point based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, and form an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value; The compensation unit 23 is used to perform curve fitting processing on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range, so as to use the error compensation function to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

[0048] like Figure 3 As shown, this application embodiment also provides an electronic device 300, including a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, it implements the steps of any of the above-described methods for ground station antenna pointing error compensation.

[0049] Since the electronic device described in this embodiment is the device used to implement a ground station antenna pointing error compensation device in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in the embodiments of this application. Therefore, how the electronic device implements the method in the embodiments of this application will not be described in detail here. Any device used by those skilled in the art to implement the method in the embodiments of this application is within the scope of protection of this application.

[0050] In practical implementation, when the computer program 311 is executed by the processor, it can achieve the following: Figure 1 Any of the corresponding implementation methods in the embodiments.

[0051] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

Claims

1. A method for compensating for pointing error of a ground station antenna, characterized in that, include: The antenna drive shaft is controlled to rotate sequentially to multiple measurement points within a preset angle range and in preset angle steps. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are synchronously acquired. The level is arranged on the reference surface of the antenna drive shaft. For each measurement point, the error value is calculated based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, forming an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value; Curve fitting is performed on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range. The error compensation function is used to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

2. The method as described in claim 1, characterized in that, The method of using the error compensation function to compensate for the pointing error of the ground station antenna includes: The error compensation function is integrated into the control program of the programmable logic controller (PLC) so that during the real-time antenna control process, the PLC reads the current command angle value of the encoder and inputs the error compensation function to calculate the current compensation error value. The compensated angle is generated based on the relationship that the compensated angle is equal to the sum of the command angle value and the current compensation error value. The compensated angle is used as the angle basis for antenna pointing control to reduce the deviation between the encoder reading and the actual angle and improve the antenna pointing accuracy.

3. The method as described in claim 1, characterized in that, The preset angle range is -90° to +90°, the preset angle step size is 5°, and the method further includes: Before acquiring the commanded angle value and the actual angle value, a preset dwell time is maintained at each measurement point to attenuate the mechanical vibration of the antenna drive shaft and stabilize the level reading.

4. The method as described in claim 1, characterized in that, The curve fitting process performed on the error sample set includes: The fitting method employs at least one of polynomial fitting or Fourier series fitting based on trigonometric functions, and determines the fitting parameters with the goal of minimizing the fitting residual, so that the error compensation function satisfies the continuity and smoothness constraints within the preset angle range.

5. The method as described in claim 1, characterized in that, The curve fitting process performed on the error sample set includes: The preset angle range is divided into multiple angle intervals, and an interval compensation function is obtained by fitting the error sample set in each angle interval. A smooth connection constraint is introduced at the connection point of adjacent angle intervals to make the function values ​​and first derivatives of the compensation functions of each interval continuous at the connection point, so as to reduce the compensation abrupt change caused by interval splicing.

6. The method as described in claim 2, characterized in that, Also includes: Before integrating the error compensation function into the PLC control program, the command angle values ​​of multiple verification measurement points are input into the error compensation function to obtain the predicted compensation error value, which is then compared with the actual error value of the corresponding verification measurement point. If the comparison result meets the preset error threshold condition, the error compensation function is solidified into a function expression or parameter table in the PLC for real-time compensation.

7. The method as described in claim 2, characterized in that, Also includes: When forming the error sample set, the command angle value and the actual angle value are collected and the error value is calculated when the antenna drive shaft reaches the measurement point in the forward direction and in the reverse direction, respectively, so as to obtain the forward error sample set and the reverse error sample set. The positive error compensation function and the negative error compensation function are respectively fitted to the positive error sample set and the negative error sample set; During real-time antenna control, the PLC selects either the forward error compensation function or the reverse error compensation function based on the direction of change of the command angle value to calculate the current compensation error value.

8. A ground station antenna pointing error compensation device, characterized in that, include: The acquisition unit is used to control the antenna drive shaft to rotate sequentially to multiple measurement points within a preset angle range and in preset angle steps. At each measurement point, the command angle value output by the encoder and the actual angle value output by the level are acquired synchronously. The level is arranged on the reference surface of the antenna drive shaft. The calculation unit is used to calculate the error value for each measurement point based on the relationship that the error value is equal to the difference between the actual angle value and the command angle value, forming an error sample set containing multiple data pairs, wherein the data pairs include the command angle value and the corresponding error value; The compensation unit is used to perform curve fitting processing on the error sample set to obtain a continuous and smooth error compensation function within the preset angle range, so as to use the error compensation function to compensate for the pointing error of the ground station antenna. The error compensation function is used to characterize the mapping relationship between the command angle value and the error value.

9. An electronic device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program stored in the memory, implements the steps of the ground station antenna pointing error compensation method as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the ground station antenna pointing error compensation method as described in any one of claims 1-7.

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