Satellite shipborne moving channel antenna control method suitable for high sea state

Abstract

This invention discloses a control method for a shipborne mobile mid-course communication antenna for medium-orbit satellites applicable in high sea states, belonging to the field of shipborne satellite communication equipment control technology. The method includes: setting a threshold for the rate of change of AGC intensity value, acquiring the current AGC intensity value in real time, and calculating the rate of change by comparing it with the AGC intensity value measured at the previous sampling time; if the rate of change is greater than or equal to the set threshold, entering the coarse alignment stage, using a PID algorithm with a large proportional coefficient for control; when the rate of change is less than the set threshold, entering the fine alignment stage, using an active compensation variable structure control algorithm for control. This invention not only improves the efficiency of the coarse alignment stage and stably tracks satellites in high sea states, improving satellite alignment accuracy in high sea states, but also does not rely on a precise mathematical model of the controlled object, making it easier to deploy in practical engineering. This invention also discloses an electronic device and storage medium for implementing the above method.

Description

Technical Field

[0001] This invention relates to a control method for a shipborne mobile communication antenna for medium-orbit satellites, specifically a control method for a shipborne mobile communication antenna for medium-orbit satellites applicable under high sea states, belonging to the field of shipborne satellite communication equipment control technology. Background Technology

[0002] Shipborne mobile communication antennas are core equipment for enabling ships to maintain continuous and stable communication with satellites during navigation. Their core control objective is to adjust the antenna's pointing direction in real time through a servo control system when the ship experiences attitude changes such as roll, pitch, and bow due to wave disturbances, ensuring the antenna remains precisely aligned with the target satellite. PID control has become the mainstream algorithm for servo control of shipborne mobile communication antennas due to its simple algorithm, convenient parameter adjustment, and ease of implementation.

[0003] Most existing shipborne mobile satellite antennas employ fixed-parameter PID control. Fixed-parameter PID control typically uses this set of parameters for control throughout the entire process after parameter calibration is completed under 0 sea state (calm sea surface). However, traditional PID algorithms have low alignment efficiency in the coarse alignment stage and rely too heavily on the integral term to eliminate steady-state errors. The integral term essentially accumulates errors over time, requiring a significant amount of time. In high sea states, with severe ship rolling, the alignment angle often changes before the integral term accumulates sufficient error, and the high speed of the satellite in medium orbit makes effective tracking impossible. Summary of the Invention

[0004] The purpose of this invention is to provide a control method for a shipborne mobile mid-course antenna for medium-orbit satellites suitable for high sea states, addressing the technical problems of low alignment efficiency and long error elimination time in the coarse alignment stage of PID control algorithms. This invention not only relies on a PID algorithm with a large Kp coefficient to rapidly increase the AGC intensity value, improving alignment efficiency in the coarse alignment stage; the active compensation variable structure control algorithm can also calculate the total disturbance of sea waves and construct a dynamic feedforward compensation channel at the control law output to achieve more timely compensation for sea waves than PID, adapting to more severe sea states and improving satellite alignment accuracy in high sea states.

[0005] To achieve the above objectives, the present invention provides a control method for a shipborne mobile mid-course antenna for medium-orbit satellites suitable for high sea states, comprising the following steps:

[0006] Step 1: Obtain the AGC intensity value at the current and previous sampling times, and calculate the rate of change of the current AGC intensity value;

[0007] Step 2: If the rate of change of the current AGC intensity value is greater than or equal to the threshold of the rate of change of the AGC intensity value, the coarse alignment stage is entered. The PID algorithm is used for control to obtain the motor speed control quantity and adjust the polarity of the speed control quantity output to the motor during this sampling, which is used to control the antenna to rotate in the direction that increases the AGC intensity value.

[0008] Step 3: If the rate of change of the current AGC intensity value is less than the threshold of the rate of change of the AGC intensity value, enter the fine alignment stage, enable the active compensation variable structure control algorithm for control, obtain the motor speed control quantity under the actual situation, and adjust the polarity of the speed control quantity output to the motor during this sampling, so as to control the antenna to rotate in the direction that increases the AGC intensity value.

[0009] Further, step 1 includes:

[0010] Step 1-1: The satellite signal is received by the sensor module, amplified and converted to intermediate frequency by a low-noise down-converter, and then transmitted to the AGC detection module through a power divider. The corresponding DC voltage is output and acquired by a high-precision analog-to-digital converter. After noise reduction and moving average filtering, the current AGC intensity value is read by the main control processor. ;

[0011] Step 1-2: Read the AGC intensity value obtained at the previous sampling time. And the sampling interval is The rate of change of the current AGC intensity value was calculated. After the calculation is complete, set the current AGC strength value. Assign to So that it can be used for the next calculation.

[0012] Further, step 2 includes:

[0013] Step 2-1: Set the target value of AGC strength to be [value missing]. Let the error Then the motor speed control quantity ,make The original form becomes ,in This is the proportionality coefficient. The integral coefficient is... These are the differential coefficients;

[0014] Step 2-2: Set the current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be opposite to that of the previous time;

[0015] Steps 2-3: Conversely, if the previously sampled AGC intensity value... Less than the current AGC strength value If the polarity of the output to the motor is the same as the previous one, the control antenna should continue to rotate in the direction that increases the AGC intensity value.

[0016] Furthermore, in step 3, the process of enabling the active compensation variable structure control algorithm for control includes:

[0017] Step 3-1: Input the target value of AGC intensity into the transient process planner and output the target signal of AGC intensity. and the target change rate signal of AGC intensity value ;

[0018] Step 3-2: Convert the motor speed control value from the previous sampling time. and the current AGC strength value The current AGC intensity value is obtained by inputting it into the disturbance observer. Observations Current AGC intensity value change rate Observations And the observed values ​​of the total disturbance of the hull by the waves. ;

[0019] Step 3-3: Construct the sliding surface And input to the non-singular terminal sliding mode error controller, where It is a constant. AGC intensity value target signal Compared with the observed value of the current AGC intensity value The error, The target rate of change signal for AGC intensity value Observed values ​​of the rate of change of AGC intensity value The error is ultimately output as the motor speed control quantity under ideal, disturbance-free conditions. ;

[0020] Steps 3-4: Observe the total disturbance of the ship's hull caused by the waves. Compensation to motor speed control quantity under ideal, disturbance-free conditions In this process, the motor speed control quantity under actual conditions is obtained. .

[0021] Further, in step 3-1, the transition process planner is represented as:

[0022] ,

[0023] in, As a tracking factor, The target value for the set AGC strength value, The target signal for AGC intensity value. The target rate of change signal for AGC intensity value. It is a symbolic function.

[0024] Further, step 3-2 includes:

[0025] The motor speed control quantity output to the motor at the previous sampling time. Current AGC strength value and sampling interval time The input is fed into the perturbation observer, which then constructs a second-order equation. ,Will Considered as the total disturbance of the hull by the waves Expanding to a new third-order state-space equation, the state-space equation becomes: ;in, The rate of change of the current AGC intensity value , for The derivative, The acceleration of the change in the current AGC intensity value. The rate of change of the total disturbance of the ship hull by the waves;

[0026] make , , These are the AGC strength values. Rate of change of AGC intensity value The total disturbance of the hull by the waves The observed values, This is the rate of change of the observed AGC intensity value. This refers to the acceleration of the change in the observed value of AGC intensity. This represents the rate of change of the observed value of the total disturbance of the ship by the waves, resulting in the observer equation: ,in , and These represent the observer gains that affect the observed and actual values ​​of AGC intensity, the observed and actual values ​​of the rate of change of AGC intensity, and the observed and actual values ​​of the difference between the observed and actual values ​​of the total disturbance of the hull caused by ocean waves, respectively.

[0027] definition The difference between the actual and observed GC intensity values The difference between the actual and observed values ​​of the AGC intensity change rate And the difference between the actual and observed values ​​of the total disturbance of the ship by the waves. Subtracting the state-space equation from the observer equation yields... Program Group Write it in matrix form Error feature matrix This is used to determine the internal dynamic characteristics, convergence rate, and asymptotic stability of the observer, by appropriately configuring the observer gain. , and This ensures that the eigenvalues ​​of the error feature matrix are all located in the left half of the complex plane, thereby guaranteeing that the difference between the actual and observed values ​​of the entire observer converges to zero rapidly at a preset exponential rate; feature selection matrix ,express The channel characteristics and decoupling path entering the observer;

[0028] The design is carried out using the bandwidth parameter method, making To optimize the observer bandwidth, all poles are configured in - At this point, the characteristic polynomial is ,and The characteristic polynomial is , can be obtained = , Finally, the current AGC strength value is obtained. Observations Current AGC intensity value change rate Observations And the observed values ​​of the total disturbance of the hull by the waves. .

[0029] Further, step 3-3 includes:

[0030] Target signal using smooth AGC intensity value Observed values ​​of AGC intensity error And the smooth AGC intensity value target rate of change signal Observed values ​​of the rate of change of AGC intensity value error Constructing the sliding surface And input to the non-singular terminal sliding mode error controller, where It is a constant;

[0031] sliding surface Taking the derivative, we get - That is, sliding surface The actual rate of change; introducing the reaching law equation This equation defines the sliding surface. The expected rate of change, where the parameter If the number is positive, the term forming the exponential approach term is: ;parameter Also positive, forming the constant-rate approaching term: Solving the equations for differentiating the sliding surface and the reaching law simultaneously, we obtain... ;

[0032] Under ideal conditions without disturbance, let the control quantity... Therefore, the expression for the motor speed control quantity under the ideal, disturbance-free condition is: ;

[0033] The observed values ​​of the total disturbance of the hull by the waves Compensation to motor speed control quantity under ideal, disturbance-free conditions The motor speed control quantity under actual conditions is obtained. .

[0034] Furthermore, in step 3, the process of adjusting the polarity of the speed control quantity output to the motor during this sampling includes:

[0035] The current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be opposite to that of the previous time;

[0036] Conversely, if the previously sampled AGC intensity value Less than the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be the same as the previous time.

[0037] The present invention also provides an electronic device, including a processor and a memory, the memory storing program code that, when executed by the processor, causes the processor to perform the steps of the method.

[0038] The present invention also provides a storage medium storing a computer program or instructions that, when the computer program or instructions are run on a computer, execute the steps of the method described.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0040] 1. To address the disturbance of the ship's hull caused by ocean waves, a disturbance observer is used to estimate the total disturbance in real time and a dynamic feedforward compensation channel is constructed at the output of the control law to achieve more timely compensation for ocean waves than PID, so as to adapt to more intense sea conditions. This solves the problem that traditional PID cannot track satellites due to the compensation lag caused by the long time for eliminating integral term errors, and greatly improves the satellite tracking accuracy under high sea conditions.

[0041] 2. To address the low alignment efficiency in the coarse alignment stage, a large-scale... The PID algorithm is used for control. The larger the value, the faster the response speed, which can quickly increase the AGC strength value and improve the alignment efficiency in the coarse alignment stage.

[0042] 3. The disturbance observer only needs to know the motor speed control value output to the motor at the previous sampling time. Current AGC strength value and sampling interval time This allows us to construct second-order equations to calculate the total disturbance of the ship's hull caused by ocean waves. This allows for compensation without relying on a precise mathematical model of the controlled object, making it easier to deploy in practical engineering. Attached Figure Description

[0043] Figure 1 A flowchart of a control method for a shipborne mobile mid-course antenna for medium-orbit satellites applicable to high sea states;

[0044] Figure 2 Flowchart of each step in the active compensation variable structure control algorithm;

[0045] Figure 3 The figure shows the simulation results of using the traditional PID algorithm under sea state 5.

[0046] Figure 4 The simulation results using this method under sea state 5 are shown in the figure. Detailed Implementation

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0048] Example 1:

[0049] This embodiment provides a control method for a shipborne moving mid-course communication antenna for medium-orbit satellites applicable in high sea states. Figure 1 As can be seen, the method includes the following steps:

[0050] S1. Obtain the current AGC strength value The AGC intensity value obtained at the previous sampling time was And the sampling interval is The rate of change of the current AGC intensity value was calculated. .

[0051] S1 specifically includes:

[0052] S11. Satellite signals are received via a sensor module, amplified and converted to intermediate frequency (IF) by a low-noise down-converter, and then transmitted to the AGC detection module via a power divider. This module incorporates a wide dynamic range RMS response RF power sensor, which accurately converts the continuously input IF signal envelope into a corresponding DC voltage. The voltage amplitude is logarithmically related to the signal strength. The output DC voltage is then acquired by a high-precision analog-to-digital converter, and after noise reduction and moving average filtering, the current AGC strength value is read by the main control processor. ;

[0053] S12. Read the AGC intensity value obtained at the previous sampling time. And the sampling interval is The rate of change of the current AGC intensity value was calculated. After the calculation is complete, the current AGC strength value will be... Assign to So that it can be used for the next calculation.

[0054] S2. Determine the threshold for the rate of change of AGC intensity value through actual measurement. A complete shipborne mobile satellite communication antenna system is required, along with a currently operational medium-Earth orbit satellite. Measurements will be conducted at sea in low sea states (1-2). The antenna will be aligned with the satellite via the ship's servo motor system, waiting for the AGC value fluctuation to be within 5 dB, and ensuring it is no less than [value missing]. The sampling rate continuously recorded 300 sets of AGC intensity values. The rate of change of AGC intensity values ​​between every two sets of data was calculated, and the maximum value was taken as the threshold of the rate of change of AGC intensity values. If the current AGC intensity value changes at a certain rate A value greater than or equal to the set threshold for the rate of change of AGC intensity value Then, in the coarse alignment stage, a PID algorithm is used for control, by increasing the proportional coefficient. Reduce the integral coefficient and differential coefficients To accelerate the response speed and increase the antenna alignment speed during the coarse alignment stage, thereby improving the alignment efficiency during this stage, the motor speed control quantity is then calculated. Then, by comparing the current AGC strength value Compared with the previously sampled AGC intensity value The magnitude of the value determines the direction of motor rotation. The positive and negative polarities control the direction of motor rotation, thus obtaining the output quantity given to the motor.

[0055] S2 specifically includes:

[0056] S21. Set the target value for AGC strength to be... Let the error Then the motor speed control quantity ,make ,in The proportionality coefficient is used to determine the basic strength of the control action; the larger the proportionality coefficient, the faster the response speed. These are the integral coefficients, used to eliminate steady-state errors; Let be the differential coefficients, which are used to adjust the control action by predicting the future trend of the error. Then the original expression becomes... By adjusting the parameters that slow down the system response speed This can rapidly increase the AGC strength value and improve the alignment efficiency in the coarse alignment stage;

[0057] S22, Set the current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value If the direction of the antenna rotation is incorrect, the polarity of the output to the motor this time should be opposite to that of the last time. Rotate the antenna in the opposite direction to increase the AGC strength value.

[0058] S23. Conversely, if the previously sampled AGC intensity value Less than the current AGC strength value If the direction of the antenna rotation is correct, the polarity of the output to the motor should be the same as the previous one, and the antenna should continue to rotate in the direction that increases the AGC strength value.

[0059] S3, if the current AGC intensity value changes at a certain rate Less than the set threshold for the rate of change of AGC intensity value At this point, the fine alignment stage begins, and the active compensation variable structure control algorithm is activated for control. The active compensation variable structure control algorithm should include, for example, the following: Figure 2 The steps shown will set the target value for the AGC strength value. The input is fed into the transient process planner, and the output is the target signal of AGC intensity value. and the target change rate signal of AGC intensity value .

[0060] S3 specifically includes: the rate of change of the current AGC intensity value. Less than the set threshold for the rate of change of AGC intensity value At this point, the fine alignment stage begins, and the active compensation variable structure control algorithm is activated for control, aiming to achieve the target value of the set AGC intensity. The input is given to the transient process planner, based on the equation. Where r is the tracking factor, which affects the output signal. The smoothness, The sign function ultimately outputs the target signal of AGC intensity value. and the target change rate signal of AGC intensity value The target change rate signal of AGC intensity value is obtained.

[0061] In this embodiment, the transition process planner can drive the AGC strength value target signal. Approximate the set target value with the most time-optimal trajectory. This greatly improves the dynamic response capability of the fine alignment stage and reduces the time required to reduce errors during the fine alignment stage.

[0062] S4. The motor speed control value at the previous sampling time. and the AGC intensity value measured in real time by the sensor. The input is fed into the disturbance observer to obtain the AGC intensity value. Observations Current rate of change of AGC intensity value Observations And the observed values ​​of the total disturbance of the hull by the waves. .

[0063] S4 specifically includes:

[0064] S41. Measure the magnitude of the control input sent to the motor at the previous sampling time. Real-time measured AGC intensity value and sampling interval time The input is fed into the perturbation observer, which constructs a second-order equation. ,Will Considered as the total disturbance of the hull by the waves This expands into a new third-order state-space equation. This is the rate of change of AGC intensity value. , for The derivative, The acceleration of the change in the current AGC intensity value. Let be the rate of change of the waves with respect to the total disturbance of the ship hull, then the state-space equation is: ;

[0065] S42, Order , , These are the AGC strength values. Rate of change of AGC intensity value The total disturbance of the hull by the waves The observed values, This is the rate of change of the observed AGC intensity value. This refers to the acceleration of the change in the observed value of AGC intensity. This represents the rate of change of the observed value of the total disturbance of the ship by the waves, and the observer equation is as follows: ,in , and It is the observer gain. The difference between observed and actual values ​​of AGC intensity is affected. The difference between observed and actual values ​​affects the rate of change of AGC intensity values. The difference between the observed and actual values ​​of the impact of ocean waves on the total disturbance of the ship needs to be reduced by selecting an appropriate observer gain.

[0066] S43, Definition That is, the difference between the actual value and the observed value of AGC intensity. That is, the difference between the actual and observed rate of change of AGC intensity value. This is the difference between the actual and observed total disturbance of the ship caused by the waves; subtracting the observer equations from the state-space equations yields the system of equations. Write it in matrix form Error feature matrix Used to determine the internal dynamic characteristics, convergence rate, and asymptotic stability of the observer, by appropriately configuring the observer gain. , and This enables the error characteristic matrix to be... The eigenvalues ​​are all located in the left half of the complex plane, thus ensuring that the difference between the actual and observed values ​​of the entire observer converges to zero rapidly at a preset exponential rate; feature selection matrix express Channel characteristics and decoupling paths entering the observer;

[0067] S44. To ensure that the observation error is small enough, the gain matrix needs to be designed so that the matrix... All eigenvalues ​​have negative real parts. The bandwidth parameter method is used for design, let... To optimize the observer bandwidth, all poles are configured in - At this point, the characteristic polynomial is ,and The characteristic polynomial is Ultimately, we can obtain = , Finally, we obtained... , Observed values ​​of the total disturbance of the hull by the waves .

[0068] Traditional control algorithms often rely on precise mathematical models of disturbances. In contrast, this invention, through step S41, unifies and merges various complex disturbances of ocean waves to the hull with unmodeled internal dynamics into a total disturbance, and expands it into a new system state. Combining the observer equations constructed in step S42, only the currently measurable AGC intensity values ​​need to be utilized. and This allows for the real-time and high-precision reconstruction of the observed total disturbance. This process completely eliminates the reliance on precise physical models of external ocean wave disturbances.

[0069] S5. Use AGC intensity value target signal Observed values ​​of AGC intensity error and AGC intensity value target change rate signal Observed values ​​of the rate of change of AGC intensity value error Constructing the sliding surface The input is fed into the non-singular terminal sliding mode error controller, where This is a constant that determines the speed of error convergence. The final output is the motor speed control quantity under ideal, disturbance-free conditions. .

[0070] S5 specifically includes:

[0071] S51, Target signal using AGC intensity value Observed values ​​of AGC intensity error and AGC intensity value target change rate signal Observed values ​​of the rate of change of AGC intensity value error Constructing the sliding surface The input is fed into the non-singular terminal sliding mode error controller, where This is a constant that determines the rate of error convergence;

[0072] S52, will Differentiation yields - i.e., sliding surface The actual rate of change is determined so that, regardless of the initial state, it can quickly and stably approach the sliding surface within a finite time. 0, Introducing the reaching law equation The approach law equation defines the sliding surface Expected rate of change, parameter It is a positive number, constituting The exponential approaching term ensures that when the error is large, it can approach the sliding surface at a very fast rate, and The larger the value, the faster the approach speed; parameters It is also a positive number, constituting isodynamic approaching term, As a sign function, it ensures that disturbances will not prevent the shipboard system from eventually reaching the sliding surface. - and Combining the two expressions yields In an ideal, disturbance-free environment, the control quantity... Direct decision ,make Therefore, the expression for the motor speed control quantity under the ideal, disturbance-free condition is: .

[0073] To address the issue of excessive time consumption in PID control algorithms for error elimination, a reaching law equation is introduced. Among them, the exponential approach term This ensures that even with a large initial error, When the size is large, it can move towards the sliding surface at an extremely high speed. Approximation significantly shortens the time required to eliminate errors; while when When smaller, The error is also relatively small, making it impossible to further approximate the error, while the constant-rate approach term... This allows for further reduction of errors when they are already small, significantly shortening the time required to eliminate errors.

[0074] S6. Observations of the total disturbance of the ship hull by the waves. Compensation to motor speed control quantity under ideal, disturbance-free conditions In this study, a dynamic feedforward compensation channel was constructed at the output end to achieve more timely compensation for ocean waves than PID control. This solved the problem that traditional PID control, due to the long time required to eliminate integral term errors, could not track satellites. Finally, the actual motor speed control quantity was obtained. Then, by comparison, the current AGC strength value is determined. Compared with the AGC intensity value obtained in one sampling The magnitude of the value determines the direction of motor rotation. The positive and negative polarities control the direction of motor rotation, thus obtaining the output quantity given to the motor.

[0075] S6 specifically includes:

[0076] S61. Observations of the total disturbance of the hull by the waves. Compensation to motor speed control quantity under ideal, disturbance-free conditions The motor speed control quantity under actual conditions is obtained. ;

[0077] S62, Set the current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value If the direction of the antenna rotation is incorrect, the polarity of the output to the motor this time should be opposite to that of the last time. Rotate the antenna in the opposite direction to increase the AGC strength value.

[0078] S63. Conversely, if the previously sampled AGC intensity value Less than the current AGC strength value If the direction of the antenna rotation is correct, the polarity of the output to the motor should be the same as the previous one, and the antenna should continue to rotate in the direction that increases the AGC strength value.

[0079] To verify the effectiveness of the method of this invention, a shipborne mobile antenna simulation platform was used. This platform can simulate a real shipborne mobile antenna system using input ephemeris data, sensor model parameters, and physical model parameters. It can also generate visualized AGC strength signal images for user reference, thereby comparing the advantages and disadvantages of different satellite alignment algorithms. First, the ship's attitude position, the physical model parameters of the antenna platform satellite, and the sensor model parameters of the gyroscope, accelerometer, and GNSS were input into the data input interface of the simulation platform. Then, ephemeris data was imported into the simulation platform. The platform can generate satellite velocity and position information based on the imported ephemeris data. Finally, the sea state was set to sea state 5, and the parameters of the actuator model (sampling time and sampling rate) were set to verify the performance of each satellite alignment algorithm under high sea state conditions. The satellite alignment algorithm model cannot be directly modified in the simulation platform; the algorithm model needs to be modified by modifying the simulation platform's code.

[0080] In the specific execution process, the physical model updates the physical world output data based on the actuator model output, the sensor model updates the sensor output data based on the data output by the physical model, the algorithm model calculates and obtains the next control target based on the sensor output information, and outputs it to the actuator. The actuator updates the actuator output based on the control target output by the algorithm model, thereby controlling the antenna of the simulation platform to rotate toward the satellite.

[0081] like Figure 3 As shown, when using the PID algorithm for antenna alignment in sea state 5, the AGC intensity variation reached 40 dB. The variation in AGC intensity reflects the antenna's satellite alignment accuracy. Excessive variation in AGC intensity using the PID algorithm indicates that the antenna cannot continuously track the satellite in high sea states, thus affecting communication quality. By adopting this method, a larger variation in AGC intensity is used in the coarse alignment stage. The PID algorithm can improve the response speed of the shipborne system and enhance the alignment efficiency in the coarse alignment stage. In the fine alignment stage, it can further improve the overall disturbance estimation in real time using an active compensation variable structure control algorithm and construct a dynamic feedforward compensation channel at the control law output to achieve more timely compensation for sea waves than PID, adapting to more severe sea conditions. This solves the problem of traditional PID's inability to track satellites due to compensation lag caused by the long time required to eliminate integral term errors. Figure 4 As shown, the antenna can rapidly increase the AGC strength value within 1 to 2 seconds after startup, improving the alignment efficiency of the coarse alignment stage by about 50%. After stabilization, the AGC strength value changes by no more than 5 dB under sea state 5, indicating that the antenna can firmly follow the satellite under high sea state. This proves that the method can not only effectively improve the alignment efficiency of the coarse alignment stage, but also track the satellite well under high sea state, thus improving the satellite alignment accuracy under high sea state.

[0082] Example 2:

[0083] This invention provides an electronic device, including a processor and a memory. The memory stores program instructions for implementing the control method for a shipborne moving mid-course antenna of a medium-orbit satellite suitable for high sea states, as described in Embodiment 1. The processor executes the program instructions stored in the memory to control the shipborne moving mid-course antenna of a medium-orbit satellite.

[0084] The processor can also be called a Central Processing Unit (CPU). A processor may be an integrated circuit chip with signal processing capabilities. A processor can also be a general-purpose processor, 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, or discrete hardware components. A general-purpose processor can be a microprocessor or any conventional processor.

[0085] The methods described in Embodiment 1 of this invention are applicable to this electronic device embodiment. The specific functions implemented by this electronic device embodiment are the same as those in the above method embodiment, and the beneficial effects achieved are also the same as those achieved by the above methods.

[0086] Example 3:

[0087] This embodiment provides a storage medium storing a computer program or instructions capable of implementing the above-described control method for a shipborne moving mid-course antenna for medium-orbit satellites in high sea states. When the computer program or instructions are run on a computer, the steps of the above-described control method for a shipborne moving mid-course antenna for medium-orbit satellites in high sea states are executed.

[0088] The computer program or instructions can be stored in the aforementioned storage medium in the form of a software product, including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks, or terminal devices such as computers, servers, mobile phones, and tablets.

[0089] The methods described in Embodiment 1 of this invention are all applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above methods.

[0090] This invention provides a control method for a shipborne mobile mid-course communication antenna for medium-orbit satellites in high sea states. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A control method for a shipborne mobile mid-course antenna for medium-orbit satellites in high sea states, characterized in that, Includes the following steps: Step 1: Obtain the AGC intensity value at the current and previous sampling times, and calculate the rate of change of the current AGC intensity value; Step 2: If the rate of change of the current AGC intensity value is greater than or equal to the threshold of the rate of change of the AGC intensity value, the coarse alignment stage is entered. The PID algorithm is used for control to obtain the motor speed control quantity and adjust the polarity of the speed control quantity output to the motor during this sampling, which is used to control the antenna to rotate in the direction that increases the AGC intensity value. Step 3: If the rate of change of the current AGC intensity value is less than the threshold of the rate of change of the AGC intensity value, enter the fine alignment stage, enable the active compensation variable structure control algorithm for control, obtain the motor speed control quantity under the actual situation, and adjust the polarity of the speed control quantity output to the motor during this sampling, so as to control the antenna to rotate in the direction that increases the AGC intensity value.

2. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 1, characterized in that, Step 1 includes: Step 1-1: The satellite signal is received by the sensor module, amplified and converted to intermediate frequency by a low-noise down-converter, and then transmitted to the AGC detection module through a power divider. The corresponding DC voltage is output and acquired by a high-precision analog-to-digital converter. After noise reduction and moving average filtering, the current AGC intensity value is read by the main control processor. ; Step 1-2: Read the AGC intensity value obtained at the previous sampling time. And the sampling interval is The rate of change of the current AGC intensity value was calculated. After the calculation is complete, set the current AGC strength value. Assign to So that it can be used for the next calculation.

3. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 1, characterized in that, Step 2 includes: Step 2-1: Set the target value of AGC strength to be [value missing]. Let the error Then the motor speed control quantity ,make The original form becomes ,in This is the proportionality coefficient. The integral coefficient is... These are the differential coefficients; Step 2-2: Set the current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be opposite to that of the previous time; Steps 2-3: Conversely, if the previously sampled AGC intensity value... Less than the current AGC strength value If the polarity of the output to the motor is the same as the previous one, the control antenna should continue to rotate in the direction that increases the AGC intensity value.

4. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 1, characterized in that, Step 3, the process of activating the active compensation variable structure control algorithm for control, includes: Step 3-1: Input the target value of AGC intensity into the transient process planner and output the target signal of AGC intensity. and the target change rate signal of AGC intensity value ; Step 3-2: Convert the motor speed control value from the previous sampling time. and the current AGC strength value The current AGC intensity value is obtained by inputting it into the disturbance observer. Observations Current AGC intensity value change rate Observations And the observed values ​​of the total disturbance of the hull by the waves. ; Step 3-3: Construct the sliding surface And input to the non-singular terminal sliding mode error controller, where It is a constant. AGC intensity value target signal Compared with the observed value of the current AGC intensity value The error, The target rate of change signal for AGC intensity value Observed values ​​of the rate of change of AGC intensity value The error is ultimately output as the motor speed control quantity under ideal, disturbance-free conditions. ; Steps 3-4: Observe the total disturbance of the ship's hull caused by the waves. Compensation to motor speed control quantity under ideal, disturbance-free conditions In this process, the motor speed control quantity under actual conditions is obtained. .

5. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 4, characterized in that, In step 3-1, the transition process planner is represented as: ， in, As a tracking factor, The target value for the set AGC strength value, The target signal for AGC intensity value. The target rate of change signal for AGC intensity value. It is a symbolic function.

6. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 4, characterized in that, Step 3-2 includes: The motor speed control quantity output to the motor at the previous sampling time. Current AGC strength value and sampling interval time The input is fed into the perturbation observer, which then constructs a second-order equation. ,Will Considered as the total disturbance of the hull by the waves Expanding to a new third-order state-space equation, the state-space equation becomes: ;in, The rate of change of the current AGC intensity value , for The derivative, The acceleration of the change in the current AGC intensity value. The rate of change of the total disturbance of the ship hull by the waves; make , , These are the AGC strength values. Rate of change of AGC intensity value The total disturbance of the hull by the waves The observed values, This is the rate of change of the observed AGC intensity value. This refers to the acceleration of the change in the observed value of AGC intensity. This represents the rate of change of the observed value of the total disturbance of the ship by the waves, resulting in the observer equation: ,in , and These represent the observer gains that affect the observed and actual values ​​of AGC intensity, the observed and actual values ​​of the rate of change of AGC intensity, and the observed and actual values ​​of the difference between the observed and actual values ​​of the total disturbance of the hull caused by ocean waves, respectively. Define the difference between the actual and observed values ​​of AGC intensity. The difference between the actual and observed values ​​of the AGC intensity change rate And the difference between the actual and observed values ​​of the total disturbance of the ship by the waves. Subtracting the state-space equations from the observer equations yields a system of equations. Write it in matrix form Error feature matrix Feature selection matrix ; The design is carried out using the bandwidth parameter method, making To optimize the observer bandwidth, all poles are configured in - At this point, the characteristic polynomial is ,and The characteristic polynomial is , can be obtained = , Finally, the current AGC strength value is obtained. Observations Current AGC intensity value change rate Observations And the observed values ​​of the total disturbance of the hull by the waves. .

7. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 4, characterized in that, Step 3-3 includes: Target signal using smooth AGC intensity value Observed values ​​of AGC intensity error And the smooth AGC intensity value target rate of change signal Observed values ​​of the rate of change of AGC intensity value error Constructing the sliding surface And input to the non-singular terminal sliding mode error controller, where It is a constant; sliding surface Taking the derivative, we get - That is, sliding surface The actual rate of change; introducing the reaching law equation This equation defines the sliding surface. The expected rate of change, where the parameter If the number is positive, the term forming the exponential approach term is: ;parameter Also positive, forming the constant-rate approaching term: Solving the equations for differentiating the sliding surface and the reaching law simultaneously, we obtain... ; Under ideal conditions without disturbance, let the control quantity... Therefore, the expression for the motor speed control quantity under the ideal, disturbance-free condition is: ; The observed values ​​of the total disturbance of the hull by the waves Compensation to motor speed control quantity under ideal, disturbance-free conditions The motor speed control quantity under actual conditions is obtained. .

8. The control method for a shipborne moving mid-course antenna for medium-orbit satellites under high sea states according to claim 1, characterized in that, In step 3, the process of adjusting the polarity of the speed control quantity output to the motor during this sampling includes: The current AGC strength value Compared with the previously sampled AGC intensity value For comparison, if the previously sampled AGC intensity value Greater than or equal to the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be opposite to that of the previous time; Conversely, if the previously sampled AGC intensity value Less than the current AGC strength value Therefore, the polarity of the output quantity sent to the motor this time should be the same as the previous time.

9. An electronic device, characterized in that, The system includes a processor and a memory, the memory storing program code that, when executed by the processor, causes the processor to perform the steps of the control method for a medium-orbit satellite shipborne mobile communication antenna applicable to high sea states, as described in any one of claims 1 to 8.

10. A storage medium, characterized in that, The system stores a computer program or instructions that, when executed on a computer, perform the steps of the method for controlling a shipborne moving mid-course antenna for medium-orbit satellites in high sea states as described in any one of claims 1 to 8.

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