Intelligent satellite television antenna and control system thereof

Abstract

The invention relates to the technical field of satellite communication, and discloses an intelligent satellite television antenna and a control system thereof, and the antenna comprises an outer cover, a mounting seat, a double-shaft rotating stand and an antenna body. The inertial measurement module is mounted on the rotating stand, and the main control module is fixed on the mounting seat. The main control module is configured to execute motion decoupling logic, and the yaw angular velocity of the carrier is separated by calculating the difference between the compound angular velocity measured by the inertia measurement module and the mechanical rotating speed fed back by the azimuth encoder; and compensating a mechanical angle difference value in a satellite capturing period by using a carrier rotation component obtained by integrating the yaw angular velocity so as to obtain a real relative azimuth angle of the target satellite in a geographic space. The self-adaptive variable-speed scanning and frequency drift correction technology is also combined, and accurate removal of carrier motion interference and high-precision autonomous satellite finding and attitude calculation are realized without external navigation and magnetic compass assistance.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, specifically to an intelligent satellite television antenna and its control system. Background Technology

[0002] Vehicle-mounted or shipborne satellite television receiving systems need to maintain antenna alignment with the target satellite throughout the vehicle's movement to ensure stable television signal reception. Currently, domestic users primarily receive television program signals from the ChinaSat 9C satellite. Traditional mobile satellite antenna systems typically rely on external auxiliary equipment for initial alignment and tracking, such as using Global Navigation Satellite Systems (GNSS) for latitude and longitude information and electronic magnetic compasses for heading reference. However, in practical applications, the metal body of vehicles or ships and the complex electromagnetic environment can easily interfere with magnetic compasses, leading to significant deviations in heading readings, which in turn can cause antenna pointing errors or satellite acquisition failures. Furthermore, some low-cost consumer-grade antenna products do not have the capability to connect to external high-precision navigation systems, requiring the antenna system to possess autonomous satellite acquisition capabilities without external navigation information assistance.

[0003] In the absence of external heading information, antennas typically require full-space blind scans to search for satellite signals. However, for moving vehicles, the vehicle's own turning motion during the scan is superimposed on the antenna's scanning motion. If the vehicle's own motion component cannot be separated, the satellite beam angle measured by the antenna will not accurately reflect the true direction of ChinaSat 9C in geospatial space, leading to signal identification errors or inability to lock onto the target satellite stably. While high-precision fiber optic gyroscopes or advanced inertial navigation systems can solve this problem, their high cost makes them unsuitable for the consumer satellite TV antenna market. Low-cost microelectromechanical systems (MEMS) gyroscopes, while inexpensive, suffer from zero-bias instability and large drift, and conventional installation methods often require complex cable connections or slip-ring transmissions, increasing the complexity of hardware design.

[0004] Furthermore, existing blind scan strategies typically employ constant scanning speeds, making it difficult to balance scanning efficiency and signal acquisition accuracy. Excessively fast scanning speeds can lead to missed scans or overshoots in weak signal areas, while excessively slow speeds increase system initialization latency. Simultaneously, the low-cost LNBs commonly used in consumer-grade satellite TV antennas are highly susceptible to ambient temperature fluctuations, exhibiting frequency drift under large temperature variations. This non-linear frequency error causes the actual received ChinaSat 9C signal frequency to differ from the parameters in the standard parameter database, resulting in satellite fingerprinting errors and further reducing the system's reliability in autonomous satellite acquisition mode. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an intelligent satellite television antenna and its control system. It solves the problems of existing mobile carrier satellite antennas being unable to effectively eliminate the interference of carrier movement on the antenna scanning angle when lacking external navigation information and magnetic compass assistance, as well as the low accuracy and slow speed of autonomous satellite finding due to frequency drift and fixed scanning strategies limited by low-cost hardware.

[0006] The first aspect of this invention provides a smart satellite television antenna.

[0007] In terms of hardware architecture, the antenna consists of an outer casing and a mounting base fixed inside it. An azimuth mount is rotatably mounted on the mounting base, and an elevation mount is hinged inside the azimuth mount. The antenna body is mounted on the elevation mount and moves with it. An azimuth encoder for measuring mechanical rotation speed is installed between the azimuth mount and the mounting base. An inertial measurement module with a sensing axis parallel to the rotation axis of the azimuth mount is mounted on the elevation mount.

[0008] The antenna employs a configuration where the inertial measurement module (IMM) is dynamically mounted. The IMM measures a composite angular velocity that includes both the carrier's motion component and the azimuth mount's rotation component. The main control module is mounted on a static mounting base and configured to execute motion decoupling logic. Specifically, the main control module obtains the composite angular velocity from the IMM and the mechanical rotation speed from the azimuth encoder. By calculating the difference between the composite angular velocity and the mechanical rotation speed and subtracting the pre-acquired static zero bias value from the gyroscope, the yaw rate of the mounting base relative to the ground is determined. The main control module uses either the trapezoidal integral method or the Simpson integral method to discretely accumulate this yaw rate to obtain the carrier's heading change during the scanning of the target satellite (ChinaSat 9C). Subsequently, the main control module uses this heading change to compensate for the mechanical angle changes recorded by the azimuth encoder during satellite acquisition, thereby eliminating observation errors caused by carrier motion and obtaining the true pointing angle of ChinaSat 9C in geospatial space.

[0009] The antenna is equipped with a servo drive module, which specifically includes an azimuth motor for driving the rotation of the azimuth mount, a pitch motor for driving the pitch mount to adjust the pitch angle of the antenna body, and a pitch encoder for measuring the pitch angle.

[0010] The antenna is equipped with an RF processing module to provide received signal strength indication, and the main control module executes an adaptive variable-speed scanning strategy. The main control module calculates the time gradient and current amplitude of the received signal strength indication in real time, and dynamically adjusts the target scanning angular velocity of the azimuth motor accordingly. Its control logic is as follows: when an increase in the absolute value of the time gradient is detected, it indicates that the signal edge has been entered, and the system automatically reduces the target scanning angular velocity to prevent overshoot; when the signal amplitude is below a preset noise threshold and the absolute value of the time gradient approaches zero, it indicates that the system is in the background noise zone, and the system controls the target scanning angular velocity to maintain it at a preset maximum cruising speed to reduce invalid waiting time.

[0011] After completing the area scan, the main control module controls the azimuth turntable to rotate to the angular position corresponding to the suspected ZhongSat 9C satellite, and obtains the satellite's second observation frequency through the radio frequency processing module. Based on the difference between the second observation frequency and the first observation frequency when the satellite was first acquired, as well as the time interval between the two measurements, the main control module calculates the linear drift rate of the local oscillator frequency. Furthermore, the main control module uses this linear drift rate to perform a uniform time linearization correction on the observation frequencies of the target satellite recorded during the scan, generating a physical layer fingerprint with consistent origins.

[0012] The main control module extracts the beam characteristics of the target satellite (ChinaSat 9C) signal from the scanned data, performs quadratic curve fitting on the signal energy distribution, and extracts the quadratic coefficients. By determining whether the value and sign of these quadratic coefficients fall within the preset effective beam range of ChinaSat 9C, ground interference or signals from non-target orbits are eliminated. After successful verification, the main control module searches the pre-stored ChinaSat 9C parameter database for candidate features that match the observed signal in physical layer parameters (such as frequency and symbol rate). Based on the matching results, the main control module calculates the deviation between the standard frequency of ChinaSat 9C and the corresponding corrected frequency, and determines whether this deviation meets the consistency threshold to confirm the lock onto ChinaSat 9C.

[0013] Based on the known longitude information of the confirmed Zhongxing-9C satellite and the mechanical angle information of the antenna body when aligned with the satellite, combined with the approximate position of the carrier (either preset or assisted input), the main control module constructs a nonlinear observation equation set. This equation set maps the carrier's true north heading angle as a state variable to the observed mechanical azimuth angle. The main control module uses an iterative numerical method to solve this equation set until the state variables converge, thereby calculating the carrier's current true north heading.

[0014] A second aspect of the present invention provides a control system for an intelligent satellite television antenna.

[0015] This control system, applied to the aforementioned smart satellite TV antenna, includes a data acquisition interface, a memory, and a processor. The data acquisition interface is configured to establish communication connections with the inertial measurement module, servo drive module, and radio frequency processing module mounted on the antenna's rotating components. The memory stores the computer program and the ChinaSat 9C parameter database. When the processor executes the computer program, it implements the following functional units:

[0016] The motion decoupling unit is used to synchronously acquire the composite angular velocity of the inertial measurement module and the mechanical rotation speed of the azimuth encoder, and calculate the difference between the two to isolate the yaw angular velocity of the carrier base.

[0017] The target reconstruction unit is used to integrate the yaw rate to obtain the carrier rotation component, and uses this carrier rotation component to compensate for the mechanical angle changes recorded during the scanning process, thus constructing observation data containing the true pointing angle.

[0018] The fingerprint correction unit is used to control the antenna to trace back to Zhongxing 9C for secondary frequency measurement, calculate the local oscillator frequency drift rate based on the ratio of frequency change to time interval, and perform linearization correction on the observed frequency.

[0019] The matching and solving unit is used to verify whether the observed signal is Zhongxing 9C in the parameter database, and to confirm the lock by calculating the frequency deviation, and then to establish a set of nonlinear equations to solve the true north heading of the carrier.

[0020] This invention, through the aforementioned technical solution, utilizes a differential combination of a low-cost inertial sensor and a mechanical encoder mounted on a rotating component to achieve precise decoupling between carrier motion and antenna scanning motion. Without the need for expensive magnetic compasses or external global navigation satellite system equipment, the system can autonomously correct angular observation errors caused by carrier motion. Furthermore, through linearization compensation and feature matching of frequency fingerprints, it achieves rapid, high-precision autonomous searching for ChinaSat 9C and course determination in highly dynamic environments.

[0021] This invention provides an intelligent satellite television antenna and its control system. It has the following beneficial effects:

[0022] 1. This invention utilizes dynamic base inertial differential measurement technology to solve the problem of interference to antenna scanning caused by the turning of a moving carrier. By directly mounting a low-cost microelectromechanical gyroscope on a rotating pitch or azimuth mount, and using the main control module to calculate the difference between the composite angular velocity measured by the gyroscope and the mechanical rotation speed fed back by the encoder, the independent yaw motion component of the carrier can be separated in real time. This method not only eliminates the need for a magnetic compass that is susceptible to interference from the ferromagnetic environment of the ship or vehicle, but also does not rely on auxiliary information from external navigation equipment, thus reducing hardware costs. At the same time, it ensures that the system can still maintain high-precision relative angle measurement capability when the carrier is turning or maneuvering, achieving fully autonomous and stable tracking.

[0023] 2. This invention employs frequency linearization correction and subgraph isomorphic matching techniques based on anchor point backtracking to achieve rapid and highly reliable satellite acquisition without prior information. Addressing the temperature drift problem commonly found in low-cost civilian LNBs, the system automatically backtracks to the first acquisition point after scanning for secondary frequency measurement, calculates the local oscillator frequency drift rate, and performs linearization compensation on the entire sequence of data, thereby obtaining a physical layer frequency fingerprint with consistent origins. By combining the true relative azimuth angle obtained through inertial differential measurement to construct the observation topology, the system can perform accurate subgraph isomorphic searches in the ephemeris database, effectively overcoming the ambiguity problem of traditional single-star matching and improving the recognition success rate in complex electromagnetic environments.

[0024] 3. This invention proposes an adaptive variable speed scanning control strategy based on signal energy gradient, which effectively balances the contradiction between blind scanning efficiency in the entire space domain and weak signal acquisition accuracy. The main control module calculates the time gradient of the received signal strength in real time, controls the motor to pass quickly at maximum cruising speed in the background noise area without signal, and rapidly reduces the speed when a signal gradient change is detected, i.e., when entering the edge of the beam, and lingers at low speed in the center of the beam. The above method avoids overshoot or missed scans caused by excessive speed in uniform speed scanning, and also prevents unnecessary time consumption caused by excessive speed, shortening the initial cold start and satellite search time of the system. Attached Figure Description

[0025] Figure 1 This is a perspective view of the present invention;

[0026] Figure 2 This is a schematic diagram of the satellite television antenna structure of the present invention;

[0027] Figure 3 This is a structural diagram of the servo drive module of the present invention;

[0028] Figure 4 This is a flowchart of the control method of the present invention.

[0029] The components include: 1. Outer casing; 2. Mounting base; 3. Azimuth mount; 4. Pitch mount; 5. Servo drive module; 501. Azimuth motor; 502. Pitch motor; 503. Azimuth encoder; 504. Pitch encoder; 6. Inertial measurement module; 7. Main control module; 8. Storage module; 9. Radio frequency processing module; and 10. Antenna body. Detailed Implementation

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see the appendix Figure 1 -Appendix Figure 4 This invention provides a control system for an intelligent satellite TV antenna. In terms of hardware physical architecture, the system mainly consists of an outer cover 1, a mounting base 2, an azimuth rotating bracket 3, a pitch rotating bracket 4, a servo drive module 5, an inertial measurement module 6, a main control module 7, a storage module 8, a radio frequency processing module 9, and an antenna body 10.

[0032] The outer cover 1 is a hemispherical or streamlined fairing with good wave transmission performance. It is fastened to the outside of the mounting base 2 by a threaded structure to form a closed internal protective space to isolate external wind, rain and salt spray corrosion. The mounting base 2 serves as the static reference platform of the entire system and is rigidly fixed to the mobile carrier (such as the top of a car or the deck of a ship) by bolts.

[0033] The internal mechanical motion components adopt a two-axis orthogonal configuration. The azimuth mount 3 is rotatably mounted on the mounting base 2 via a large-diameter bearing, forming the azimuth rotation axis of the system. The elevation mount 4 is hinged inside the azimuth mount 3, forming the elevation rotation axis of the system. The antenna body 10 is fixedly mounted on the elevation mount 4 and moves with it in elevation.

[0034] The main control module 7 is encapsulated in an electromagnetic shielding box and rigidly mounted on a static mounting base 2. This layout not only utilizes the heat dissipation area of ​​the base but also avoids the cable tangling problem caused by the main control circuit rotating with the antenna. The storage module 8 is integrated on the circuit board of the main control module 7 in the form of a surface-mount memory chip or a pluggable card slot, and is used to store the ephemeris database and runtime topology table.

[0035] The servo drive module 5 specifically includes an azimuth motor 501, a pitch motor 502, an azimuth encoder 503, and a pitch encoder 504. The azimuth motor 501 is installed at the bottom of the mounting base 2 and drives the azimuth rotating frame 3 to rotate relative to the mounting base 2. The pitch motor 502 is installed on the side of the azimuth rotating frame 3 and drives the antenna body 10 to perform pitch adjustment. The azimuth encoder 503 and the pitch encoder 504 are coaxially installed at the rotation centers of the azimuth axis and the pitch axis, respectively, for real-time feedback of mechanical angles.

[0036] The inertial measurement module 6 is mounted on the top structure of the pitch turret 4. The radio frequency processing module 9 is mounted on the side of the pitch turret 4, close to the signal output end of the antenna body 10, in order to shorten the length of the radio frequency cable and reduce signal transmission loss. The main control module 7 establishes electrical connections with the servo drive module 5, the inertial measurement module 6 and the radio frequency processing module 9 located on the rotating part through the internal bus led out by the slip ring, forming a closed-loop control network.

[0037] The input of the RF processing module 9 is connected to the low-noise block downconverter (LNB) at the feed of the antenna body 10. The RF processing module 9 integrates a broadband tuner circuit and a baseband demodulation circuit. The broadband tuner circuit receives the 1-band intermediate frequency (IF) signal. Its internal variable gain amplifier (VGA), driven by automatic gain control (AGC) logic, dynamically adjusts the gain according to the strength of the input signal and outputs a quantized Received Signal Strength Indicator (RSSI) voltage value. This RSSI value is then converted from analog to digital to generate a digitized signal. The signal stream is transmitted to the main control module 7 for gradient calculation during the scanning process.

[0038] The baseband demodulation circuit is configured to perform blind scan operations. Its internal hardware search engine automatically scans the spectrum at preset frequency steps and symbol rate ranges. When carrier energy is detected, it initiates a carrier recovery loop locking signal and extracts physical layer parameters. The main control module 7 reads these parameters to obtain the current satellite's spectral fingerprint characteristics, specifically including: downlink center frequency. Symbol rate and forward error correction bit rate .

[0039] The main control module 7, installed on the mounting base 2, is configured to execute the following core logic:

[0040] First, motion decoupling and target locking logic is executed. The main control module 7 obtains the composite angular velocity from the inertial measurement module 6 and the mechanical rotation speed from the azimuth encoder 503; by calculating the difference between the two and subtracting the zero bias, the yaw angular velocity of the mounting base 2 relative to the ground is separated; the yaw angular velocity is integrated over time to obtain the change in the carrier's heading (…). This change is used to compensate for the mechanical angle changes recorded by the azimuth encoder 503 before and after the acquisition time of the target satellite (Zhongxing-9C), thereby obtaining the true pointing angle of Zhongxing-9C in geospatial space. This eliminates interference from carrier motion on antenna pointing measurements. Secondly, frequency fingerprint correction logic is executed. The main control module 7 uses an anchor point backtracking mechanism to obtain the linear drift rate of the local oscillator frequency (…). The drift rate is then used to perform time linearization correction on the original observation frequencies of the target satellite nodes recorded during the scanning process, mapping the frequency data captured at different times to a unified time reference point to obtain corrected frequencies with consistent origins. This eliminates errors caused by hardware temperature drift.

[0041] The inertial measurement module 6 contains only a microelectromechanical system (MEMS) rate gyroscope; the system does not include a magnetometer. The sensing axis of the inertial measurement module 6 is parallel to the azimuth rotation axis of the system. Since the inertial measurement module 6 rotates together with the azimuth mount 3, the angular velocity it measures... It is the superposition of the carrier's ground-to-ground turning angular velocity and the azimuth turner's rotational angular velocity relative to the carrier.

[0042] In order to obtain simple carrier motion information for differential compensation, the main control module 7 executes the following decoupling logic: the main control module 7 reads the mechanical angular velocity fed back by the orientation encoder 503. and the total angular velocity output from inertial measurement module 6 Subtracting this mechanical component, the true yaw rate of the carrier base (i.e., mounting base 2) relative to the ground can be calculated. :

[0043] ;

[0044] in, Indicates time The actual yaw rate of the carrier base relative to the ground. Indicates time The measured total angular velocity output by inertial measurement module 6; Indicates time The mechanical rotation speed fed back by the orientation encoder 503 is the rotational angular velocity of the orientation rotating frame 3 relative to the mounting base 2. This represents the static zero-bias estimate of the gyroscope.

[0045] During sector scanning, the main control module 7 does not calculate the carrier's absolute heading, but rather the relative rotation angle of the carrier during the scanning of the Star 9C beam. By performing discrete integration, the change in the carrier's heading can be obtained. :

[0046] ;

[0047] in, Indicates from time At that time The total change in the carrier's heading during the period; Indicates the first The yaw rate of the carrier at each sampling time; This indicates the sampling period of inertial measurement module 6; and Indicates the start and end times of the integration; This is the index for discrete sampling time.

[0048] Subsequently, the main control module 7 uses the rotational component of the carrier to compensate for the reading difference of the mechanical orientation encoder 503, and calculates the true pointing angle of Zhongxing-9C in geographic space:

[0049] ;

[0050] in, This indicates the actual pointing angle of ChinaSat 9C in geographic space; This indicates the mechanical angle value output by the azimuth encoder 503 when locking onto the Zhongxing 9C satellite; This represents the change in the carrier's heading. With the above configuration, even if the inertial measurement module 6 is mounted on a rotating component, the system can still accurately eliminate interference from the carrier's motion on the antenna pointing measurement, achieving high-precision target locking.

[0051] The main control module 7 is internally equipped with a topology matching operation unit. The storage module 8 pre-stores the standard signal parameters of ChinaSat 9C in the form of an adjacency list. The main control module 7 first performs signal beam feature extraction. It extracts the energy distribution characteristics of the ChinaSat 9C signal beam from the scan data and fits a quadratic curve using the least squares method. .

[0052] in, This represents the fitted signal intensity function; Indicates the scanning angle as the independent variable; , , These are the coefficients of the quadratic term, the linear term, and the constant term, respectively. The main control module 7 uses the quadratic term coefficients... Numerical characteristics (such as curvature amplitude and aperture direction) are used to determine whether the scanned signal sequence conforms to the geometric characteristics of the ChinaSat 9C beam, thereby eliminating false target sequences caused by interference from nearby satellites or ground clutter.

[0053] The main control module 7 further performs parameter matching search. The main control module 7 constructs an observation feature vector, which includes the physical layer fingerprint (symbol rate, FEC) and center frequency. The main control module 7 searches for candidate solutions for parameter matching in the database and determines whether to lock onto Zhongxing 9C through local oscillator frequency offset consistency check.

[0054] During the attitude inversion phase, the main control module 7 constructs a set of nonlinear observation equations to determine the unknown true north heading angle of the carrier. As a state variable, the main control module 7 uses the Gauss-Newton iterative method to solve for it. During the iteration, the main control module 7 calculates the Jacobian matrix J, whose elements are derived from the theoretical azimuth angles. and theoretical pitch angle The first-order partial derivatives of the three state variables are used to construct the equation. The main control module 7 continuously updates the state estimate until the residual converges, and outputs the final pose determination result.

[0055] Finally, the main control module 7 executes target redirection. Based on the confirmed position of ChinaSat 9C, the main control module 7, combined with its own calculated state, calculates the theoretical angle of the target and generates mechanical control commands. The signal is sent to the servo drive module 5, which drives the azimuth motor 501 and the pitch motor 502 to complete the alignment.

[0056] in, This is the azimuth control command sent to the servo system; This is the theoretical azimuth angle of Zhongxing 9C relative to the carrier position; The current true north heading angle of the carrier is calculated by attitude inversion.

[0057] This invention also provides a control method for an intelligent satellite TV antenna. Based on the aforementioned hardware architecture, the method uses a main control module 7 as the execution entity. By coordinating the servo drive module 5, the radio frequency processing module 9, and the inertial measurement module 6, it achieves autonomous search and acquisition of the ChinaSat 9C signal in an environment without external navigation information assistance.

[0058] Step S100: Adaptive variable speed sector scan

[0059] After the system is powered on, the main control module 7 controls the antenna to perform azimuth scanning at a preset elevation angle and calculates the received signal strength indication in real time. time gradient To resolve the efficiency and accuracy trade-off in traditional uniform-speed blind scanning, the main control module 7 implements an energy gradient-based variable-speed strategy, adjusting the azimuth scanning angular velocity in real time according to the following formula. It can quickly pass through areas with no signal, slow down at the edge of the signal, and stay at a low speed in areas with high signal, in order to achieve efficient capture.

[0060] ;

[0061] in, for The target scanning angular velocity at any given moment; and These are the maximum and minimum scan rates, respectively. The signal threshold; This represents the gradient sensitivity coefficient; The strength retention factor; The signal strength gradient; This represents the signal strength value.

[0062] Step S200: Single-star pointing correction based on inertial differential

[0063] During the scanning process, to eliminate interference from the carrier's own rotation on the angle measurement of Zhongxing-9C, the main control module 7 executes an inertial integration decoupling algorithm. The main control module 7 simultaneously acquires the angular velocity from the inertial measurement module 6. Mechanical rotation speed of the orientation encoder 503 The yaw rate of the carrier itself was calculated. During the scanning of the 9C beam of the satellite, the main control module 7 pairs... Integrating the components yields the rotational component of the carrier. It also dynamically compensates for changes in the mechanical encoder angle and calculates the true pointing angle of Zhongxing-9C in geographic space. :

[0064] ;

[0065] in, This indicates the actual pointing angle of ChinaSat 9C in geographic space; This indicates the mechanical angle value output by the azimuth encoder 503 when locking onto the Zhongxing 9C satellite; This represents the change in the carrier's heading.

[0066] Step S300: Physical Layer Fingerprint Extraction and Frequency Linearization Compensation. To eliminate the temperature drift nonlinearity error of the low-cost low-frequency head (LNB), the main control module 7 executes an anchor point backtracking resampling mechanism. After scanning, the main control module 7 forces the antenna to rotate back to the ChinaSat 9C signal point (anchor point) for secondary frequency measurement. Using the frequency difference and time difference between the two measurements, the linear drift rate of the local oscillator frequency is calculated. .

[0067] ;

[0068] in, This refers to the drift rate; and These are the frequency measurements at the backtracking time and the initial time, respectively; and These are the corresponding timestamps.

[0069] Subsequently, the main control module 7 uses this drift rate to normalize and correct the observation frequency of Zhongxing 9C, providing physical layer fingerprint data for subsequent source verification.

[0070] Step S400: Single-star feature matching and verification

[0071] The main control module 7 first performs beam geometry validity verification on the scanned signal sequence. It extracts the coordinates of the signal beam, fits a quadratic curve using the least squares method, and extracts the coefficients of the quadratic term. Since the ChinaSat 9C beam typically exhibits specific energy distribution characteristics during ground observation, the main control module 7 eliminates false target sequences caused by ground interference or other non-ChinaSat 9C components based on whether the sign and amplitude of these quadratic term coefficients fall within a preset valid range. After verification, the main control module 7 searches the ChinaSat 9C parameter database for parameters, filtering out candidate features that match the attributes. For any ambiguous solutions, the main control module 7 performs a local oscillator frequency offset consistency check, calculates the frequency deviation variance of each candidate group, and selects the combination with the smallest variance as the unique true matching result.

[0072] Step S500: Single-satellite assisted attitude calculation and closed-loop tracking

[0073] Based on the known longitude and corresponding observation angle of the successfully matched Zhongxing-9C satellite, and combined with the preset carrier position, the main control module 7 establishes a set of nonlinear observation equations including the carrier's true north heading angle. The main control module 7 uses iterative numerical methods such as the Gauss-Newton method to solve the equations until the state variables converge, thus completing the system's autonomous attitude determination. After successful solution, the main control module 7 calculates the target pointing angle based on the theoretical position of Zhongxing-9C and its own heading, drives the antenna to complete the final alignment, and enters closed-loop tracking mode.

[0074] The following section elaborates on each step of the above access guidance control method, combining specific control logic and algorithm models.

[0075] Detailed implementation of step S100:

[0076] Step S110: Navigation-free mode initialization and scan start

[0077] After power-on, the main control module 7 executes a self-test program. When the system detects that no external Global Navigation Satellite System (GNSS) receiver is connected, or that the connected positioning module is invalid, it automatically enters the autonomous satellite acquisition mode without navigation. The main control module 7 reads the configuration parameters from the storage module 8, obtains the preset search elevation angle and scanning parameters, and sends a position control command to the elevation motor 502 through the servo drive module 5, driving the elevation axis of the antenna body 10 to move to the preset search elevation angle position. This search elevation angle is usually set to the statistical average elevation angle of the local satellite orbits or the elevation angle retained from the last power-off.

[0078] Subsequently, the main control module 7 controls the azimuth motor 501 to drive the antenna body 10 to perform full-space scanning in the azimuth axis direction. For the specific driving method of the azimuth motor 501, the main control module 7 generates pulse control signals or bus speed commands to drive the azimuth turntable 3 to rotate.

[0079] Step S120: Real-time calculation of signal energy gradient

[0080] During antenna azimuth scanning, the RF processing module 9 operates continuously. The broadband tuner circuit inside the RF processing module 9 performs down-conversion and gain adjustment on the received RF signal, outputting an analog voltage value reflecting the current signal strength. This voltage value is then converted from analog to digital to form a time-discrete digital signal strength sequence. The data is transmitted to the main control module 7. The main control module 7 uses a fixed sampling period. The signal strength data is read and subjected to a moving average filter to suppress high-frequency thermal noise.

[0081] Main control module 7 calculates the real-time time gradient of signal strength. This gradient characterizes the rate of change of signal intensity over time (i.e., with the scanning angle). Specifically, the main control module 7 uses a first-order or higher-order difference algorithm to calculate the gradient value:

[0082] ;

[0083] in, Indicates the current sampling time; The current sampling time The signal strength gradient value; For the current moment The signal strength value; The previous sampling time The signal strength value; This represents the sampling time interval.

[0084] Step S130: Adaptive variable speed control based on energy gradient

[0085] To address the issues of excessive time consumption during constant-speed scanning in weak signal regions and the potential for tuners to fail to lock onto or overshoot peak values ​​due to excessive rotation speed in strong signal regions (within the satellite beam range), main control module 7 implements an adaptive variable-speed control strategy based on energy gradients. This strategy establishes a negative feedback mechanism between the scanning angular velocity and signal characteristics. Main control module 7 adjusts the speed control based on the current signal strength... and its gradient The target scanning angular velocity at the current moment is calculated using a preset nonlinear control law. .

[0086] The specific calculation formula for this nonlinear control law is as follows:

[0087] ;

[0088] in, express Target scanning angular velocity at time and azimuth; This indicates the preset maximum cruise scan speed of the system; This indicates the preset precision capture scan speed; Represents the absolute value of the signal strength gradient; This represents the preset background noise threshold. This represents the gradient sensitivity coefficient, used to adjust the speed response rate to the steepness of signal edges, rapidly reducing the rotational speed when a sharp gradient change is detected. This represents the intensity retention coefficient, used to adjust the degree of speed response to the absolute amplitude of the signal; This represents the signal strength value at the current moment.

[0089] This formula reflects the following control logic: when the detected signal strength is below the noise threshold... Furthermore, when the gradient approaches zero (i.e., in a flat region with no signal), the denominator approaches 1, and the system approaches... Rapid scanning; when a signal gradient is detected. When the denominator increases (i.e., when entering the edge of the satellite beam), the scanning speed decreases rapidly to prevent overshoot; when in the center peak region of the beam, although the gradient... It will decrease and approach zero, but because The term remains a large positive value, and the denominator also remains a large value, thus forcing the system to maintain a low speed. Nearby, ensure that the RF processing module 9 has enough time to complete demodulation and locking at the beam center.

[0090] Step S140: Lock interrupt and node record

[0091] The main control module 7 will calculate the... The signal is converted into corresponding motor drive commands and sent to the servo drive module 5. Simultaneously with the variable speed scanning, the baseband demodulation circuit of the RF processing module 9 attempts to perform carrier recovery and frame synchronization on the signal.

[0092] When the RF processing module 9 successfully locks onto the carrier and extracts the physical layer parameters (center frequency, symbol rate, forward error correction code rate), the lock flag bit in its internal status register flips to a valid state. After the main control module 7 detects that the lock flag bit is valid through interrupt or high-frequency polling, it immediately executes the braking logic to control the azimuth motor 501 to stop rotating or enter the micro-step adjustment mode.

[0093] Main control module 7 records the current value of the azimuth encoder 503. Pitch encoder 504 numerical value The instantaneous angular velocity output by the inertial measurement module 6 The physical layer fingerprint features demodulated by the radio frequency processing module 9 are packaged into a satellite observation node data packet and stored in the dynamic runtime data area of ​​the storage module 8 to complete the capture of a scanning node. For the specific read / write operations of motor braking control and data storage, those skilled in the art can use conventional low-level drivers for implementation.

[0094] Detailed implementation of step S200:

[0095] Step S210: Synchronous acquisition and time alignment of multi-source data

[0096] Throughout the sector scanning process, the main control module 7 establishes a unified system time base. The main control module 7 synchronously acquires the angular velocity data output by the inertial measurement module 6 and the mechanical angle data fed back by the servo drive module 5 at a fixed high frequency (e.g., 100Hz-1kHz).

[0097] Since the inertial measurement module 6 is physically mounted on the azimuth mount 3, its sensitive axis (Z-axis) follows the azimuth.

[0098] The rotating frame 3 rotates relative to the mounting base 2. Therefore, the raw angular velocity signal output by the inertial measurement module 6... This includes the steering component of the carrier relative to the ground and the rotation component of the azimuth mount relative to the carrier. The main control module 7 simultaneously reads the pulse count value from the azimuth encoder 503 and calculates its first-order differential, or reads the speed observation value from the servo drive, to obtain the mechanical rotational angular velocity of the azimuth mount relative to the mounting base 2. Main control module 7 will and Perform timestamp alignment and store in a circular buffer.

[0099] Step S220: Motion decoupling calculation under the rotating base

[0100] The main control module 7 executes a motion decoupling algorithm to extract the carrier's own motion information from the total angular velocity. Based on the principles of rigid body kinematics, the main control module 7 calculates the true yaw rate of the carrier base (mounting seat 2) relative to the ground. The calculation formula is as follows:

[0101] ;

[0102] in, This represents the true yaw rate of the carrier base relative to the geographic coordinate system at time t; This represents the measured total angular velocity output by inertial measurement module 6 at time t; The mechanical rotation speed fed back by the azimuth encoder 503 at time t is the rotational angular velocity of the azimuth rotating frame 3 relative to the mounting base 2. This represents the direction coefficient. It is set to 1 when the rotation direction definition of the inertial measurement module 6 is consistent with the rotation direction definition of the orientation encoder 503, and -1 when they are opposite. This represents the static zero-bias estimate of the gyroscope, which can be obtained by averaging the values ​​during the system's power-on static initialization phase, or by real-time estimation using a Kalman filter.

[0103] Step S230: Discrete integral of the carrier's relative heading drift

[0104] When the system captures the first [number] times during the scanning process... satellites (time) ) and the satellites (time) At that time, the main control module 7 calculates the total change in heading of the carrier between these two moments. Since it is not necessary to know the absolute heading, the main control module 7 only calculates the decoupled angular velocity of the carrier. Perform definite integral operations. In the digital system, the main control module 7 uses either the trapezoidal integration method or Simpson's integration method for discrete accumulation:

[0105] ;

[0106] in, Indicates from the captured number satellite time To capture the first satellite time During this period, the total drift angle of the carrier's heading; Indicates the first The yaw rate of the carrier calculated at each sampling time. Indicates the sampling period; , These are the system clock stamps at the time the corresponding satellite lock-in event occurred.

[0107] Step S240: Differential compensation for target pointing angle

[0108] The main control module 7 uses the calculated carrier heading drift to correct the angle difference recorded by the mechanical encoder, thereby obtaining the true pointing angle of Zhongxing-9C in the geospatial coordinate system. The correction formula is as follows:

[0109] ;

[0110] in, This indicates the actual pointing angle of ChinaSat 9C in geographic space; This indicates the mechanical angle value output by the azimuth encoder 503 when locking onto the Zhongxing 9C satellite; This represents the change in the carrier's heading.

[0111] Step S250: Construction of target feature vector

[0112] Based on the above processing results, the main control module 7 constructs an observation feature vector for subsequent matching. The main control module 7 treats the captured Zhongxing 9C as a node, with node attributes including the physical layer fingerprint recorded in step S140; the main control module 7 uses the corrected true pointing angle as an auxiliary attribute. The main control module 7 stores this observation data in the runtime data area of ​​the storage module 8, preparing for comparison with the standard parameters of Zhongxing 9C.

[0113] Detailed implementation of step S300:

[0114] Step S310: Resampling mechanism based on anchor point backtracking

[0115] After the main control module 7 finishes scanning the entire azimuth axis or acquires a preset number of satellite nodes, it performs an anchor point backtracking operation. The main control module 7 extracts the first valid acquisition node from the scanning sequence from the storage module 8, defines it as the observation anchor point, and drives the azimuth motor 501 through the servo drive module 5 to control the antenna body 10 to rotate to the mechanical azimuth angle corresponding to the observation anchor point.

[0116] The radio frequency processing module 9 performs secondary locking and parameter extraction on the anchor point satellite, while the main control module 7 records the system clock stamp at the retrospective moment and the remeasured satellite downlink center frequency. By repeatedly observing the same physical target at different time points, the system obtains the frequency change caused by hardware system deviations (mainly temperature drift).

[0117] Step S320: Calculation of local oscillator frequency drift rate

[0118] The main control module 7 uses the observation data from the initial scan time and the backtracking resampling time to calculate the linear drift rate of the local oscillator frequency within the scan period. The calculation formula is as follows:

[0119] ;

[0120] in, The real-time linear drift rate represents the local oscillator frequency of the LNB; Indicates the time of backtracking The downlink center frequency value obtained by performing secondary measurements on the observation anchor point; Indicates the initial time. The downlink center frequency value measured when the observation anchor point was first captured; Indicates the system clock stamp used to perform resampling; This indicates the system clock stamp initially captured.

[0121] The drift rate It reflects the frequency deviation trend of the hardware system over time.

[0122] Step S330: Linearization correction of the whole sequence observation frequency. The main control module 7 uses the calculated drift rate. Time compensation is performed on the frequencies of all satellite nodes stored in the dynamic runtime data area. By mapping frequency data captured at different times to a unified time reference point, the accumulated frequency error caused by scanning time is eliminated. The correction formula is as follows:

[0123] ;

[0124] in, express The corrected downlink center frequency of each satellite node after time compensation is used as the physical layer fingerprint feature for subsequent matching. Indicates the scanning time The actual measured number The original value of the downlink center frequency of each satellite node; Indicates the first The system clock stamp corresponding to when a satellite node is locked.

[0125] Through the above calculations, the frequency observations that originally exhibited a stepped or sloping change due to temperature drift were corrected into static fingerprint data with reference value from the same source.

[0126] Step S340: Encapsulation of physical layer fingerprint feature vectors

[0127] The main control module 7 will correct the center frequency. Symbol rate extracted by RF processing module 9 at the moment of lock-on Forward error correction bit rate The signal polarization method is combined to form the physical layer fingerprint feature vector of each satellite node. :

[0128] ;

[0129] in, Indicates the generated first Physical layer fingerprint feature vector of each satellite node; Indicates the first The downlink center frequency of each satellite node after correction in step S330; This indicates the demodulated result obtained by the RF processing module 9. Symbol rate of each satellite node; This indicates the demodulated result obtained by the RF processing module 9. Forward error correction code rate per satellite node.

[0130] This eigenvector is related to the relative azimuth angle calculated in step S240. Together, these constitute the complete attributes of the observation topology subgraph. Since the corrected frequency data eliminates time-varying interference from the hardware itself, the observation results of the same region and the same type of hardware for the same group of satellites exhibit physical consistency, providing a reliable data foundation for subsequent subgraph matching with sub-Hertz precision in massive ephemeris databases. The normalization processing and storage logic of the fingerprint feature vector can be implemented using conventional fixed-point or floating-point arithmetic by those skilled in the art, and will not be elaborated upon here.

[0131] Detailed implementation of step S400:

[0132] Step S410: Curvature determination of beam geometry features

[0133] The main control module 7 first verifies the beam geometry validity of the observed signal sequence. It selects at least three signal sampling points with valid angular coordinates from the observed data to construct an azimuth-signal intensity coordinate set. The main control module 7 then uses the least squares method to perform quadratic curve fitting on this coordinate set to establish a geometric model of the beam energy.

[0134] ;

[0135] in, This represents the fitted signal intensity function; Indicates the scanning angle as the independent variable; The coefficients of the quadratic term characterize the curvature features of the swept beam; The coefficient of the first-order term represents the tendency of the trajectory to slope. is the coefficient of the constant term.

[0136] Main control module 7 extracts quadratic coefficients As a geometric criterion for beam characteristics. Since geostationary orbit satellites typically exhibit a specific arc-shaped arrangement relative to ground observation points, the main control module 7 uses the judgment coefficients. Does it fall within the preset effective experience range? Specifically, the main control module 7 utilizes a coefficient The sign and amplitude of the orbital trajectory help determine the geographic hemisphere in which the carrier is located. For example, when observed in the mid-to-high latitudes of the Northern Hemisphere, the GEO orbital arc typically opens downwards (i.e.,...). The geometric features of ); if the fitting results show If the amplitude exceeds the threshold, the main control module 7 determines that the currently scanned signal sequence is a ground interference source or a non-GEOT satellite, and marks it as an invalid sequence, suspending subsequent matching to save computing power.

[0137] Step S420: Feature-based single-star search

[0138] After passing the geometric verification, the main control module 7 executes the feature matching algorithm. The storage module 8 contains a pre-stored database of Zhongxing-9C parameters; the main control module 7 then uses the observed satellite physical layer fingerprint vectors... (Including corrected frequencies) The symbol rate (SR) and forward error correction rate (FEC) are compared item by item with the preset parameters of ChinaSat 9C in the database.

[0139] Parameter attribute constraints: The symbol rate SR and the forward error correction code rate FEC must be completely consistent;

[0140] Corrected observation frequency The absolute value of the difference between the frequency and the standard frequency of ChinaSat 9C is less than the preset coarse capture tolerance.

[0141] Step S430: Local oscillator frequency offset consistency check and locking

[0142] For the candidate results output in step S420 (typically for Zhongxing 9C), the main control module 7 further performs a fine-grained verification of the frequency deviation. The main control module 7 calculates the deviation between the standard frequency and the corrected observed frequency:

[0143] ;

[0144] The main control module 7 determines the deviation value. Is the target less than the preset locking threshold? If so, the target is confirmed to be ChinaSat 9C, and the lock is successful; otherwise, it is determined to be interference from a neighboring satellite in the same frequency band, and the scan continues.

[0145] Detailed implementation of step S500:

[0146] Step S510: Construction of the nonlinear observation equation system

[0147] The main control module 7 extracts data from the Zhongxing 9C information determined in step S440.

[0148] Main control module 7 establishes the observation equations. The true north heading angle of the carrier. It is the only unknown state variable. The theoretical azimuth angle of Zhongxing-9C relative to the carrier. Compared with the observed mechanical azimuth angle The following geometric relationship exists:

[0149] ;

[0150] in, It is based on the approximate location of the carrier and the known longitude of Zhongxing 9C. The theoretical azimuth angle calculated using the spherical trigonometry formula; For measuring noise.

[0151] Step S520: Iterative Solution and State Inversion

[0152] Main control module 7 constructs information about unknown quantities. The nonlinear observation equations are used (or solved directly using the above linear relationships; if the coupling effect of pitch angle is considered, it becomes nonlinear). The main control module 7 uses iterative numerical methods (such as the Gauss-Newton method) or direct algebraic methods to solve for the current true north heading of the carrier. .

[0153] Note: Since only one satellite is observed, the system relies on preset approximate latitude and longitude. If the carrier moves a long distance (across provinces), the error in the approximate position will introduce heading calculation error. However, within a typical provincial area, this error meets the alignment accuracy requirements for satellite television reception.

[0154] Step S530: Target Redirection and Initial Alignment

[0155] After calculating the carrier's precise latitude, longitude, and true north heading, the system switches from blind search mode to orientation mode. The main control module 7 utilizes its preset or calculated position... , Using the longitude of Zhongxing-9C, the theoretical azimuth angle of Zhongxing-9C relative to the carrier was calculated using standard spherical trigonometric functions. and theoretical pitch angle .

[0156] Subsequently, the main control module 7 will determine the theoretical azimuth angle. Subtract the calculated current true north heading The mechanical azimuth angle command required for the antenna to rotate is obtained. Theoretical pitch angle Directly used as a mechanical pitch angle command .

[0157] Main control module 7 will and The signal is sent to the servo drive module 5, which drives the azimuth motor 501 and the pitch motor 502 to quickly align the antenna body 10 to the theoretical position of the target satellite.

[0158] Step S540: Beam scanning and closed-loop tracking maintenance

[0159] After mechanical alignment is completed, the main control module 7 controls the servo drive module 5 to perform a small-range spiral scan or cross scan to search for signal peaks. When the RF processing module 9 locks onto the ChinaSat 9C signal again and the signal quality exceeds the demodulation threshold, the system enters closed-loop tracking mode.

[0160] During the closed-loop tracking phase, the main control module 7 uses the high-frequency angular velocity data from the inertial measurement module 6 as a feedforward quantity to isolate high-frequency disturbances of the carrier in real time; it uses the signal strength gradient from the radio frequency processing module 9 as a feedback quantity to correct long-period pointing drift. This composite control strategy combining inertial feedforward and radio frequency feedback ensures that the antenna always points precisely at the target satellite during movement. For the specific tuning of the composite PID control law parameters, those skilled in the art can perform conventional adjustments based on the motor response characteristics.

Claims

1. An intelligent satellite television antenna, characterized by, The utility model relates to a kind of antenna systems, including: Cover (1) and fixed to its inside pedestal (2), rotatablely mounted with azimuth turntable (3) on the pedestal (2), hinged with elevation turntable (4) inside the azimuth turntable (3), antenna body (10) is installed on the top of the elevation turntable (4);Azimuth encoder (503) for measuring mechanical rotating speed is equipped between the azimuth turntable (3) and the pedestal (2), inertial measurement module (6) for measuring the compound angular velocity including carrier motion component and azimuth turntable rotation component is installed on the sensitive shaft of the elevation turntable (4) and the rotating shaft of the azimuth turntable (3) is parallel; Master module (7) is installed on the pedestal (2), configured to: obtain the compound angular velocity from the inertial measurement module (6), and obtain the mechanical rotating speed from the azimuth encoder (503);Perform motion decoupling logic, separate out the yaw angular velocity of the pedestal (2) relative to the earth by calculating the difference between the compound angular velocity and the mechanical rotating speed;The yaw angular velocity is time integrated to obtain the carrier heading change amount, and the mechanical angle difference recorded by the azimuth encoder (503) in target satellite capture process is compensated using the carrier heading change amount, to obtain the real relative azimuth angle of Zhongxing 9C in geographical space.

2. A smart satellite television antenna as claimed in claim 1, wherein, The master module (7) is configured to: Subtract the mechanical rotating speed fed back by the azimuth encoder (503) from the compound angular velocity output by the inertial measurement module (6), and deduct the pre-acquired gyro static zero offset value, to obtain the yaw angular velocity of the carrier base; And the yaw angular velocity of the carrier base is calculated by discrete accumulation using trapezoidal integration method or Simpson integration method, to obtain the carrier heading change amount during scanning target satellite beam.

3. The smart satellite television antenna according to claim 1, wherein, Further comprising: Servo drive module (5) includes azimuth motor (501) for driving the rotation of the azimuth turntable (3); Elevation motor (502) is included in the servo drive module (5) for driving the elevation turntable (4) to adjust the elevation angle of the antenna body (10); Elevation encoder (504) is used for measuring the elevation angle of the elevation turntable (4).

4. The smart satellite television antenna according to claim 1, wherein, Further comprising radio frequency processing module (9) for providing received signal strength indication; The master module (7) is configured to execute adaptive variable-speed scanning strategy: Real-time calculation of time gradient of received signal strength indication, the time gradient represents the rate of change of signal strength with scanning angle; According to the time gradient and the current amplitude of the received signal strength indication, calculate the target scanning angular velocity;Wherein, the control logic is configured to: When the absolute value of the time gradient increases, the target scanning angular velocity is reduced;When the current amplitude is lower than the preset noise threshold and the absolute value of the time gradient tends to zero, control the target scanning angular velocity to maintain at a preset maximum cruising speed.

5. A smart satellite television antenna as claimed in claim 4, wherein, Further comprising radio frequency processing module (9) for measuring the observation frequency of satellite signal. The main control module (7) is also configured to: after completing the scan, control the azimuth turntable (3) to rotate to the angle position corresponding to the captured target satellite, so as to obtain the second observation frequency of the satellite through the radio frequency processing module (9); calculate the linear drift rate of the local oscillator frequency based on the difference between the second observation frequency and the first observation frequency when the satellite was first captured and the time interval; and use the linear drift rate to linearize and correct the observation frequency of the target satellite recorded during the scan.

6. A smart satellite television antenna as claimed in claim 5, wherein, The main control module (7) is also configured to perform single-satellite signal feature verification: The energy distribution characteristics of the target satellite signal beam are extracted from the scan data, and a quadratic curve is fitted to the signal strength data. The quadratic coefficients of the fitted quadratic curve are extracted, which characterize the curvature characteristics of the main lobe of the beam. Determine whether the value and sign of the quadratic term coefficient fall within the preset effective range of the target satellite signal beam characteristics. If it falls within the effective range, then the current acquisition signal is determined to be valid.

7. A smart satellite television antenna as claimed in claim 5, wherein, It also includes a storage module (8) for storing a standard parameter database of the target satellite; The main control module (7) is also configured to perform target feature matching and source consistency verification: compare the observed satellite signal physical layer parameters with the preset parameters of the target satellite in the standard parameter database; and calculate the deviation between the standard frequency of the target satellite and the corresponding corrected frequency based on the matching result. Determine whether the deviation value is less than a preset locking threshold. If it is, confirm it as a target satellite and lock it.

8. A smart satellite television antenna as claimed in claim 7, characterized in that, The main control module (7) is also configured to perform attitude inversion: Based on the known longitude information of the satellite identified as the target satellite, and the mechanical angle information of the antenna body (10) when aligned with the satellite, combined with the preset approximate position of the carrier, a set of nonlinear observation equations is constructed. The set of nonlinear observation equations maps the true north heading angle of the carrier as an unknown state variable to the observed mechanical azimuth angle. The set of nonlinear observation equations is solved by an iterative numerical method until the state variables converge, so as to calculate the current true north heading of the carrier.

9. The smart satellite television antenna according to claim 1, wherein, The main control module (7) is encapsulated in an electromagnetic shielding box and rigidly connected to the mounting base (2); the inertial measurement module (6) contains only a microelectromechanical system rate gyroscope and does not contain a magnetometer. The inertial measurement module (6) is installed on the top structure of the pitch turret (4), and its sensitive axis is parallel to the rotation axis of the azimuth turret (3).

10. A control system for a smart satellite television antenna, characterized in that, The control system, applied to a smart satellite TV antenna as described in any one of claims 1-9, comprises: The data acquisition interface is configured to establish a communication connection with the inertial measurement module (6), the servo drive module (5), and the radio frequency processing module (9) mounted on the antenna rotating component; The memory (8) stores computer programs and a database of target satellite parameters; The processor, connected to the data acquisition interface and the memory (8), implements the following functional units when executing the computer program: The motion decoupling unit is used to synchronously acquire the composite angular velocity of the inertial measurement module (6) and the mechanical rotation speed of the azimuth encoder (503), and calculate the difference between the two to separate the yaw angular velocity of the carrier base. The target reconstruction unit is used to integrate the yaw angular velocity to obtain the carrier rotation component, and use the carrier rotation component to compensate for the mechanical angle changes recorded during the scanning process, and construct target observation data containing the true pointing angle. The fingerprint correction unit is used to control the antenna to trace back to the target satellite for secondary frequency measurement, calculate the local oscillator frequency drift rate based on the ratio of frequency change to time interval, and perform linearization correction on the observed frequency. The matching and solving unit is used to verify the matching degree between the observed signal and the target satellite characteristics in the parameter database, and to confirm the target lock by calculating the frequency deviation, and then to establish a set of nonlinear equations to solve the true north heading of the carrier.

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