Satellite searching system and method of ground terminal

Abstract

The invention relates to the technical field of satellite communication, and discloses a satellite searching system and method for a ground terminal, and the system comprises a master device which is provided with a first antenna and a second antenna, the first antenna is used for communicating with a slave device, and the second antenna is used for receiving a low-orbit satellite beacon signal; the slave device is provided with a first antenna and a second antenna, the first antenna is used for communicating with the master device, and the second antenna is used for receiving a beacon signal of a satellite; the synchronization module is used for synchronizing the clocks of the master device and the slave device; and the master device calculation module calculates the position of the satellite in the master device coordinate system in combination with the position of the slave device. Intercommunication between the master device and the slave device is realized through the first antenna, the master device calculates the accurate position of the satellite according to the time difference and the position by using the timestamp data of the slave device, and the positioning problem when ephemeris information is lost or cannot be updated in real time is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite communication, and particularly to a satellite search system and method for a ground terminal. Background Art

[0002] In modern satellite communication systems, communication between a ground terminal and a satellite requires accurate satellite position data. Usually, the satellite position is obtained through ephemeris data (such as TLE data or real-time ephemeris data). The ephemeris provides the satellite's orbital information, enabling the ground terminal to calculate the precise position of the satellite and, based on this, perform signal transmission and reception.

[0003] However, obtaining accurate ephemeris data may be restricted in some cases, especially when real-time ephemeris data is not available or the satellite orbital information cannot be updated in real time. Against this background, traditional satellite positioning systems may be affected by problems such as communication interruptions, loss of ephemeris information, or delayed updates, resulting in the ground terminal being unable to accurately obtain the position of the satellite. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a satellite search system and method for a ground terminal, which solves the problem that the ground terminal cannot accurately obtain the satellite position when real-time ephemeris data cannot be obtained or the satellite orbital information cannot be updated in a timely manner.

[0005] To achieve the above object, the present invention is realized through the following technical solutions: A satellite search system for a ground terminal, comprising: A main device, having a first antenna and a second antenna, wherein the first antenna is used for communicating with a slave device, and the second antenna is used for receiving low-earth orbit satellite beacon signals; A slave device, having a first antenna and a second antenna, wherein the first antenna is used for communicating with the main device, and the second antenna is used for receiving the beacon signal of the satellite and transmitting the satellite beacon signal to the main device through the first antenna; A synchronization module, used for synchronizing the clocks of the main device and the slave device; A main device calculation module, which calculates the position of the satellite in the coordinate system of the main device based on the time difference of the slave device receiving the satellite beacon signal after synchronization and in combination with the position of the slave device.

[0006] Preferably, the synchronization module includes a Kalman filter algorithm unit for estimating and optimizing the clock synchronization error between the main device and the slave device.

[0007] Preferably, the main device further includes a signal processing module for preprocessing the satellite beacon signal transmitted by the slave device and transmitting it to the main device calculation module. The preprocessing includes: A denoising unit, which is used to remove environmental noise in the received satellite beacon signal; An enhancement unit, which is used to enhance the received satellite beacon signal.

[0008] Preferably, the system further includes an antenna beam pointing module, which is used to adjust the pointing of the second antennas of the master device and the slave device according to the position of the satellite in the coordinate system of the master device.

[0009] A satellite search method for a ground terminal, including the following steps: Arrange the master device and the slave device, and establish a communication connection between the master device and the slave device; Use the slave device to receive the beacon signal of the satellite, record the signal reception time, and transmit it to the master device; The master device calculates the position of the satellite in the coordinate system of the master device based on the beacon signal of the satellite and the signal reception time.

[0010] Preferably, a plurality of slave devices are provided, and after the plurality of slave devices are communicatively connected to the master device, clock synchronization is performed, and the time synchronization uses the Kalman filtering algorithm: where K k is the Kalman gain; P k-1 is the estimated error covariance matrix at the previous moment, indicating the degree of the estimated error at the previous moment; H k is the observation matrix; R k is the observation noise covariance matrix, indicating the noise magnitude and uncertainty in the observation process; is the transpose of the observation matrix.

[0011] Preferably, the position of the satellite in the coordinate system of the master device is calculated by using the least squares algorithm, and the formula of the least squares algorithm includes: where is the satellite position calculated by the master device; x satellite represents the position vector of the satellite in three-dimensional space, and this position vector is the target to be solved; N is the number of devices participating in the calculation, indicating the quantity of signal data; x i is the position of the i-th slave device; d i is the distance from the slave device i to the satellite; ∥x i -x satellite ∥ is the estimated distance from the slave device i to the satellite.

[0012] Preferably, after the position of the satellite in the coordinate system of the master device is obtained, the relative angles between the master device antenna and the slave device antenna and the satellite are adjusted according to the position of the satellite in the coordinate system of the master device.

[0013] The present invention provides a satellite search system and method for a ground terminal. It has the following beneficial effects: 1. In the present invention, the master device and the slave devices communicate with each other through the first antenna. Subsequently, based on the signals received by the slave devices and the reception time difference, the position of the satellite is calculated, achieving the technical effect of accurately calculating the satellite position even when ephemeris data cannot be obtained. Through the cooperation of the master device and multiple slave devices, using the timestamps of the satellite beacon signals received by the slave devices, the master device can calculate the accurate position of the satellite according to the time difference and the device positions. Compared with the prior art method of relying on ephemeris data for positioning, the present invention effectively solves the problem of inability to locate the satellite when ephemeris information is lost or cannot be updated in real time through the cooperation of the slave devices and timing analysis.

[0014] 2. By introducing multi-device cooperation and the Kalman filter clock synchronization algorithm, the present invention ensures high-precision clock synchronization between multiple slave devices and the master device, thereby improving the accuracy of satellite positioning calculation. Through the Kalman filter algorithm, the master device can optimize clock synchronization according to the time differences between the slave devices, reducing the influence of clock deviation on the signals. Compared with the prior art where signal processing deviation may occur due to clock synchronization error, the present invention improves the synchronization accuracy, ensures the accuracy of signal reception, and thus enhances the reliability of satellite positioning calculation.

[0015] 3. By denoising and enhancing the satellite beacon signals, the present invention significantly improves the quality of the received signals. Through denoising and signal enhancement processing, the influences of environmental noise and signal attenuation are eliminated, ensuring the data accuracy in the satellite positioning process. Compared with the prior art solutions that fail to adequately handle signal noise and weak signal problems, the present invention greatly reduces noise interference through signal processing techniques, ensures more stable and clear signal reception, and significantly improves the accuracy of positioning.

[0016] 4. By adjusting the pointing angle of the antenna based on the position of the satellite in the coordinate system of the master device, the present invention realizes stable reception of satellite signals. After calculating the azimuth angle and elevation angle of the satellite, the antennas of the master device and the slave devices can be automatically adjusted to ensure that the antennas always point to the satellite position, maximizing the signal reception quality. Compared with the prior art where the antenna positioning error is large or manual adjustment is required, the present invention not only improves the efficiency of signal reception through the automated antenna adjustment process, but also ensures the stability and efficiency in the communication process, solving the problems of delay and inaccuracy that may occur during manual antenna adjustment in traditional methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the system architecture of the present invention; Figure 2Schematic diagram of the method flow of the present invention. Detailed implementation mode

[0018] Next, in combination with the drawings in the specification of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] In order to better understand the present invention, the above content will be described in detail below in combination with specific embodiments.

[0020] Please refer to the attached Figure 1 , the embodiment of the present invention provides a satellite search system for a ground terminal, including: The main device has a first antenna and a second antenna. The first antenna is used for communicating with the slave device, and the second antenna is used for receiving low-earth orbit satellite beacon signals; The slave device has a first antenna and a second antenna. The first antenna is used for communicating with the main device, and the second antenna is used for receiving the beacon signal of the satellite and transmitting the satellite beacon signal to the main device through the first antenna; In this embodiment, the satellite search system of the ground terminal includes a main device and a slave device. The main device and the slave device are wirelessly interconnected through the first antenna. Specifically, the main device is equipped with two antennas. Among them, the first antenna is used for data communication with the slave device, responsible for exchanging positioning information, synchronizing data and other system status information. The second antenna is specifically used for receiving the beacon signal of the low-earth orbit satellite and receiving the positioning signal from the satellite for subsequent positioning and signal processing.

[0021] The slave device is also equipped with two antennas. The first antenna is used for communication with the main device to ensure the efficient transmission of data and signals. The second antenna is used for receiving the beacon signal emitted by the satellite to obtain the position information of the satellite. When the slave device receives the satellite beacon signal, the slave device records the reception time of the signal and transmits these signal data to the main device through the first antenna. The main device calculates the specific position of the satellite in the coordinate system of the main device based on the satellite signal and time information received by the slave device and the relative positions of the devices.

[0022] The synchronization module is used to synchronize the clocks of the main device and the slave device; In this embodiment, the synchronization module is used for clock synchronization between the main device and the slave device. Since in the satellite search system of the ground terminal, the main device and the slave device need to work together to receive satellite beacon signals and perform data processing, the clock accuracy between the devices is crucial for the accuracy and stability of the entire system.

[0023] The synchronization module can avoid the errors caused by clock deviation to signal reception and position calculation. Specifically, clock synchronization can be achieved in various ways, such as using existing synchronization protocols, external synchronization signal sources, or correcting the clock through software algorithms. The most common implementation method is to use the Kalman filtering algorithm to estimate and optimize the clock difference between devices, so as to adjust the clock synchronization accuracy of the devices.

[0024] In some embodiments, the synchronization module can also perform dynamic correction according to the real-time communication between devices and the signal reception time, gradually correcting the clock error, so that the system always maintains a high-precision time synchronization state, thereby providing a reliable data basis for subsequent signal processing and positioning calculation.

[0025] The master device calculation module calculates the position of the satellite in the master device coordinate system based on the time difference of the slave device receiving the satellite beacon signal after synchronization, in combination with the position of the slave device.

[0026] In this embodiment, the master device calculation module uses the time difference of the slave device receiving the satellite beacon signal and the position of the slave device to calculate the position of the satellite in the master device coordinate system.

[0027] Specifically, the master device calculation module first relies on the synchronized signal time data, and uses the time difference of the slave device receiving the satellite beacon signal (i.e., the time difference of different devices receiving the signal) to determine the propagation delay of the signal. Since the clocks of the master device and the slave device have been accurately aligned through the synchronization module, the master device can accurately obtain and utilize the timestamp of each slave device receiving the signal, so as to perform accurate time difference calculation.

[0028] Then, in combination with the known position data of the slave device, the master device calculation module uses the principle of triangulation or other positioning algorithms to perform satellite positioning based on the time difference and position information between devices. By calculating the propagation time of the satellite signal and the relative position between devices, the master device can obtain the accurate position of the satellite. This calculation process may involve considerations of the signal propagation speed (such as the speed of light) and the distance between devices.

[0029] In some embodiments, the master device calculation module uses algorithms such as the least squares method and Kalman filtering to optimize the calculation of the satellite position. These algorithms improve the accuracy of satellite positioning by reducing the error between the predicted position and the actually received signal time difference. Finally, the calculation result gives the position of the satellite in the master device coordinate system, and provides data support for subsequent antenna adjustment, communication optimization, etc.

[0030] Through this calculation module, the master device can not only calculate the position of the satellite according to the beacon signal, but also continuously calibrate and optimize the accuracy of the position calculation to ensure the efficient operation of the ground terminal satellite search system.

[0031] Please refer to the appendix Figure 2 , an embodiment of the present invention also provides a method for a ground terminal to search for satellites, including the following steps: Arrange the master device and the slave device, and establish a communication connection between the master device and the slave device; In this embodiment, the method for a ground terminal to search for satellites includes arranging the master device and the slave device, and establishing a communication connection between the master device and the slave device. Specifically, the master device and the slave device establish a connection through wireless communication technology to ensure that the two can exchange signals and data in real time. Through this communication connection, the master device and the slave device can cooperate to jointly complete tasks such as satellite signal reception, clock synchronization, signal processing, and satellite positioning.

[0032] In some embodiments, the communication connection between the master device and the slave device can use radio frequency bands or other appropriate communication methods, such as Wi-Fi, Bluetooth, Lora, Zigbee, etc., and select the appropriate communication method according to the requirements of the actual application scenario. Through the wireless communication connection, the master device can receive the timestamp data of the satellite beacon signal from the slave device, and perform processing such as signal synchronization, denoising, and enhancement on the signal. At the same time, the slave device can timely feedback the received signal information to the master device to ensure the accuracy and real-time of the data.

[0033] In addition, the communication connection between the master device and the slave device is not limited to data transmission. The two can also maintain the consistency of the clock through a signal synchronization mechanism to ensure that the moments when each device receives the satellite beacon signal are highly synchronized, and avoid signal delay errors caused by clock asynchronization. In particular, the communication connection is a key link in this embodiment, and the cooperation and coordination between the master device and the slave device are the basis for the efficient operation of the entire satellite search system.

[0034] In specific implementation, through the wireless communication connection between the master device and the slave device, the master device can not only obtain the signal reception time and other relevant data of the slave device, but also perform satellite positioning calculations according to the received satellite beacon signal and timestamp information when necessary. During the process of the master device calculating the satellite position, it is also necessary to optimize the calculation result according to the position information of the slave device, the signal reception moment, and the synchronized time difference, so as to improve the accuracy of satellite positioning.

[0035] To ensure the accurate transmission of signals, measures such as encryption and data integrity check may be involved during the communication connection process to ensure the security and reliability of the communication channel between the master device and the slave device. In some embodiments, the communication connection may also support remote configuration and upgrade, thereby further enhancing the flexibility and adaptability of the system.

[0036] Specifically, during the establishment process of the communication connection, the following steps are included: The master device and the slave device initialize the wireless communication channel through methods such as frequency band selection and channel access.

[0037] The master device and the slave device determine the communication protocol through negotiation and start the data transmission process to ensure that the slave device can transmit signal data to the master device.

[0038] After the communication connection is established, the master device and the slave device can synchronize clocks, exchange data, and update the status information in real time during subsequent signal processing.

[0039] In some embodiments, the implementation method of the communication connection may vary according to the environment. For example, in a complex environment, it may be necessary to enhance the signal transmission ability, or in the case of a long communication distance, a low-power, long-distance communication method needs to be selected.

[0040] Therefore, through the communication connection between the master device and the slave device, the system can maintain efficient cooperation during signal reception, processing, and satellite positioning. The implementation of this part not only ensures that the slave device can transmit the satellite beacon signal to the master device in real time, but also ensures that the master device can calculate the precise position of the satellite through accurate clock synchronization, providing reliable data support for subsequent satellite positioning.

[0041] The slave device receives the beacon signal of the satellite and records the signal reception time, and transmits it to the master device; In this embodiment, the satellite search method of the ground terminal includes using the slave device to receive the beacon signal of the satellite and record the signal reception time, and then transmitting this signal time information to the master device for further processing. Specifically, the system obtains the timestamp information through the process of the slave device receiving the satellite beacon signal, and sends this data to the master device through the communication connection for position calculation.

[0042] In some embodiments, the slave device receives the beacon signal emitted by the low-earth orbit satellite through the second antenna. The satellite beacon signal contains the positioning information of the satellite, and while the slave device receives these signals, it records the time of signal reception. This timestamp data is crucial information in subsequent satellite positioning calculations and is usually recorded in a high-precision time synchronization manner to ensure the accuracy and timing consistency of the signals.

[0043] Specifically, the moment recorded by the timestamp data is the exact moment when the slave device receives the satellite beacon signal, and this moment is recorded relative to the time reference of the system synchronization. Each slave device generates a corresponding timestamp according to the time when it receives the satellite beacon signal, and sends this time information to the master device through the first antenna.

[0044] The transmission of signal timestamp data is accomplished through wireless communication technology. Specifically, the slave device sends signal time information and possibly other relevant data (such as received signal strength, error correction values, etc.) to the master device via its first antenna. At this time, after the master device receives this signal information from the slave device, it can calculate the precise position of the satellite based on the time difference and position information between the slave devices.

[0045] In a possible implementation, the communication between the slave device and the master device may be based on protocols such as Wi-Fi, Bluetooth, Lora and other wireless communication technologies to ensure the effective transmission and synchronization of data. To avoid interference or data loss during signal transmission, the communication process may include means such as encryption and verification to ensure the reliability and security of the data.

[0046] And multiple slave devices are set up. The master device can perform positioning calculations based on the satellite beacon signals received by multiple slave devices, thereby improving the accuracy of the calculation results. However, due to possible deviations in the clocks of different devices, differences in the timestamps of signal reception occur, which will affect the accuracy of the positioning calculation. Therefore, estimate and optimize the clock synchronization error between the master device and the slave devices to ensure that all devices process signal data within a unified time frame.

[0047] Specifically, the clock synchronization process is as follows: The goal of clock synchronization: After each slave device receives the satellite beacon signal and records the signal reception time, it will transmit its time data to the master device. To make the signal data between the master device and the slave devices consistent, it is necessary to synchronize the clocks between the devices. The clock difference between the master device and the slave devices is estimated and gradually optimized by the Kalman filtering algorithm, so as to ensure that the master device and the slave devices work synchronously under the same time reference.

[0048] The Kalman filtering algorithm is used to estimate and correct the clock deviation between the devices according to the signal reception timestamps recorded by the slave devices and the position information between the devices. Specifically, the Kalman filter can dynamically adjust the clock synchronization value through the feedback mechanism of prediction and measurement to reduce error accumulation and improve synchronization accuracy.

[0049] In the Kalman filtering algorithm, the Kalman gain K k is calculated by the formula: where, K k is the Kalman gain; P k-1 is the estimated error covariance matrix of the previous moment, indicating the degree of the estimated error of the previous moment; H k is the observation matrix; R k is the observation noise covariance matrix, indicating the size and uncertainty of the noise in the observation process; is the transpose of the observation matrix.

[0050] Through the Kalman filtering algorithm, the master device can dynamically adjust the clock synchronization error based on the signal timestamp data of the slave device, and further optimize the clock deviation between the master device and the slave device.

[0051] In some embodiments, the Kalman filter is not limited to simple time synchronization, but can also estimate the relative position between devices and the signal propagation delay, further improving the accuracy of signal processing. Through this state estimation, the Kalman filter can help the master device adapt to changes in clock deviation in a dynamic environment, thus maintaining high-precision clock synchronization.

[0052] Therefore, by dynamically adjusting the clock synchronization error between the master device and the slave device, it can ensure that devices in the ground terminal satellite search system work under the same time reference. Through the Kalman filtering algorithm, the system can efficiently estimate the clock deviation, optimize the synchronization accuracy, and provide high-quality time data for subsequent satellite positioning calculations.

[0053] In some embodiments, after the satellite beacon signal transmitted by the slave device is transmitted to the master device, it can also be denoised and enhanced, specifically including: Denoising: Since satellite signals are usually interfered with, resulting in a decline in signal quality. How to accurately process signal noise and restore the true signal is the key to improving positioning accuracy. Therefore, the Bayesian inference method is used to estimate the noise in the signal. The Bayesian inference method updates the probability distribution of the signal by combining prior knowledge and real-time data, thus effectively removing noise.

[0054] The Bayesian inference model is as follows: where θ represents the latent parameter of the signal; x m is the received signal; P(θ) is the prior probability distribution; P(x m |θ) is the likelihood function; P(x m ) is the normalization constant; P(θ|x m ) is the posterior probability.

[0055] Therefore, through the Bayesian inference method, signal noise suppression can be achieved, and the signal quality can be made higher, thus providing more accurate data for subsequent satellite positioning.

[0056] Enhancement: It is used to enhance the received satellite beacon signal. Satellite beacon signals are usually transmitted through the air to ground receiving devices, but during the transmission process, due to distance, environmental interference or signal attenuation, the signal strength may weaken, thus affecting the positioning accuracy and system stability. Therefore, after receiving the satellite beacon signal, the enhancement unit performs enhancement processing to improve the quality and strength of the signal.

[0057] Signal enhancement usually includes the following aspects: Power amplification: When the received satellite beacon signal is weak, the gain control may not be sufficient to meet the system requirements. In this case, the enhancement unit can further enhance the power of the signal through power amplification technology. The power amplifier can effectively enhance the signal strength by increasing the power of the signal, especially in long-distance or signal attenuation environments, to ensure stable signal transmission; Multipath interference suppression: During the propagation process, satellite signals may be reflected or refracted, resulting in multipath effects and signal interference. The enhancement unit can use multipath effect suppression technology to reduce the impact of reflected signals on received signals. By synthesizing and correcting multiple received signals through algorithms, the enhancement unit can effectively restore the original signal and improve the accuracy of the signal.

[0058] Therefore, through enhancement processing, the enhancement unit can significantly improve the quality of the received satellite beacon signal, enhance the signal strength and improve the signal-to-noise ratio. The combination of these technologies ensures the accuracy and stability of the signal, and reduces the impact of signal attenuation, noise interference and multipath effects on satellite positioning calculations. Ultimately, the enhanced satellite beacon signal provides more reliable data support for subsequent positioning calculations, beam pointing adjustments and other operations, ensuring that the system operates efficiently and achieves the desired positioning accuracy.

[0059] The master device calculates the position of the satellite in the master device coordinate system based on the satellite's beacon signal and the signal reception time.

[0060] In this embodiment, the master device calculates the position of the satellite in the master device coordinate system based on the received satellite beacon signal and its signal reception time. In order to ensure accurate satellite positioning, the master device relies on the signal data and timestamp information provided by the slave device, combined with the position of the slave device, to calculate the precise position of the satellite.

[0061] Specifically, the satellite beacon signal contains the distance information between the satellite and the receiving device, and the signal reception time provides a time reference for calculating these distances. The signal propagation speed (usually the speed of light) and the time difference between devices can be used to calculate the distance between the satellite and each receiving device. Combined with the position information of the slave device, the master device can calculate the precise position of the satellite in three-dimensional space through mathematical methods such as triangulation or least squares method.

[0062] Specifically, the calculation process of the master device includes the following steps: Signal reception and time recording: When the satellite beacon signal is received, the slave device records the reception time of the signal. This time is recorded relative to a known reference moment in the coordinate system of the master device. These timestamp information are used by the master device to calculate the signal propagation delay and further to calculate the relative position of the satellite.

[0063] Calculation of signal propagation time: The timestamp T of each slave device receiving the satellite signal i represents the time experienced by the signal propagation from the satellite to the device. According to the formula: d i =c·(T i -T 0 ); where, d i is the distance from slave device i to the satellite; c represents the signal propagation speed; T i is the timestamp when slave device i receives the satellite beacon signal; T 0 is the system reference time, serving as the time reference benchmark.

[0064] Positioning in combination with slave device positions: Once the master device collects the timestamp information of multiple slave devices and their corresponding signal reception time differences, it can use this information to deduce the position of the satellite. Specifically, the master device will use the known position information and distances of the slave devices, and use triangulation or the least squares method for optimization calculation to derive the spatial position of the satellite.

[0065] For the data of multiple slave devices, the master device can calculate the satellite position through the following least squares algorithm: where, is the satellite position calculated by the master device; x satellite represents the position vector of the satellite in three-dimensional space, and this position vector is the target to be solved; N is the number of devices participating in the calculation, representing the quantity of signal data; x i is the position of the i-th slave device; d i is the distance from slave device i to the satellite; ∥x i -x satellite ∥ is the estimated distance from slave device i to the satellite.

[0066] By minimizing the difference between the estimated distance and the actual measured distance of each slave device, the master device can obtain the optimal position of the satellite.

[0067] Therefore, the master device calculates the position of the satellite in the master device coordinate system by using mathematical algorithms such as the least squares method, combining the satellite beacon signal and the signal reception time provided by the slave device with the position data of the slave device. Through these steps, the master device can accurately locate the position of the satellite, improving the positioning accuracy and system stability.

[0068] After the master device calculates the position of the satellite in the master device coordinate system, according to the position of the satellite, the master device will adjust the relative angles between the master device antenna and the slave device antenna and the satellite to ensure that the antennas point to the satellite, thus realizing stable and efficient satellite-ground communication.

[0069] Specifically, the antenna adjustment is achieved by accurately calculating the pointing angle of the antenna. According to the position of the satellite in the master device coordinate system, the master device calculates the specific direction that the antenna needs to point to and adjusts the antennas of the master device and the slave device so that they can accurately align with the satellite. This adjustment process includes, but is not limited to, the adjustment of the azimuth angle and the elevation angle to ensure that the antenna can receive signals from the satellite while improving the communication quality and positioning accuracy.

[0070] Among them, determination of the satellite position: In the foregoing steps, the master device calculates the position of the satellite in the master device coordinate system through the received satellite beacon signal and the signal reception time of the slave device. This position is usually represented by three-dimensional coordinates, including the x, y, and z coordinates of the satellite in space. Specifically, the satellite position is obtained by calculating the distance information and position data of multiple slave devices.

[0071] Antenna angle calculation: When calculating the relative angles required for antenna adjustment, it is first necessary to know the position of the satellite and the initial direction of the antenna. According to the three-dimensional coordinates x satellite , y satellite , z satellite of the satellite, the relative angles between the master device and slave device antennas and the satellite can be calculated. These angles usually include the azimuth angle and the elevation angle.

[0072] The calculation formula for the azimuth angle θ is: Among them, y satellite and x satellite are the components of the satellite position on the y and x axes respectively, and the azimuth angle θ represents the horizontal angle from the antenna reference direction (usually the north or a certain reference direction) to the satellite.

[0073] The calculation formula for the elevation angle φ is: Among them, z satelliteis the vertical component of the satellite's position, and the elevation angle φ represents the vertical angle at which the antenna points to the satellite.

[0074] By calculating these two angles, the antennas of the master device and the slave device can be precisely adjusted to point relative to the satellite.

[0075] Antenna adjustment process: Once the azimuth angle and elevation angle are calculated, the antennas of the master device and the slave device can adjust their mechanical structures or electronic control systems to make the antenna point in the calculated direction. The specific adjustment method may involve the following steps: The rotation mechanisms of the master device antenna and the slave device antenna usually include an electric motor or a servo system, which can adjust the antenna pointing according to the calculated angles.

[0076] Through precise azimuth angle and elevation angle adjustment, ensure that the maximum gain direction of the antenna is aligned with the position of the satellite, thereby achieving the best signal reception and transmission performance.

[0077] Adjustment and optimization: In some embodiments, the antenna adjustment may involve continuous small adjustments. Whenever the satellite position changes (e.g., due to the satellite's orbital change), the master device will recalculate and adjust the antenna pointing according to the new satellite position. This process can ensure that the antenna always maintains the best alignment with the satellite, especially in low Earth orbit (LEO) satellite applications where the relative position between the satellite and the ground device changes rapidly and frequent antenna pointing optimization is required.

[0078] Therefore, the master device calculates the azimuth angle and elevation angle required for antenna adjustment based on the satellite position, and then adjusts the antenna pointing of the master device and the slave device to the satellite through these angles. This precise antenna adjustment method ensures stable reception of satellite signals, improves communication quality and positioning accuracy. In a dynamically changing environment, real-time antenna adjustment is crucial for ensuring the efficient operation of the system.

[0079] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A satellite search system for a ground terminal, characterized in that: include: A master device having a first antenna and a second antenna, wherein the first antenna is used to communicate with the slave device, and the second antenna is used to receive a low-orbit satellite beacon signal; A slave device having a first antenna and a second antenna, wherein the first antenna is used to communicate with the master device, and the second antenna is used to receive a satellite beacon signal and transmit the satellite beacon signal to the master device through the first antenna; A synchronization module, used for synchronizing the clocks of the master device and the slave device; The master device calculation module calculates the position of the satellite in the master device coordinate system based on the time difference of the synchronized slave device receiving the satellite beacon signal and the position of the slave device.

2. A satellite search system for a ground terminal according to claim 1, characterized in that: The synchronization module includes a Kalman filter algorithm unit for estimating and optimizing the clock synchronization error between the master device and the slave device.

3. A satellite search system for a ground terminal according to claim 1, characterized in that: The master device further includes a signal processing module for preprocessing the satellite beacon signal transmitted from the slave device and transmitting the preprocessing to the master device computing module, wherein the preprocessing includes: A denoising unit, used to remove environmental noise from received satellite beacon signals; The enhancement unit is used to enhance the received satellite beacon signal.

4. A satellite search system for a ground terminal according to claim 1, characterized in that: The system also includes an antenna beam pointing module for adjusting the second antenna pointing of the master device and the slave device according to the position of the satellite in the master device coordinate system.

5. A satellite search method for a ground terminal, based on a satellite search system for a ground terminal according to any one of claims 1 to 4, characterized in that: The following steps are involved: Arrange the master device and the slave device, and establish communication connection between the master device and the slave device; Using the slave device to receive the satellite beacon signal and record the signal reception time, and transmit it to the master device; The master device calculates the position of the satellite in the master device coordinate system based on the satellite's beacon signal and the signal reception time.

6. A satellite search method for a ground terminal according to claim 5, characterized in that: The slave devices are provided with a plurality of them, and the plurality of slave devices are connected to the master device for clock synchronization, and the time synchronization uses a Kalman filter algorithm: Among them, K k is the Kalman gain; P k-1 is the estimation error covariance matrix of the previous moment, indicating the degree of estimation error of the previous moment; H k is the observation matrix; R k is the observation noise covariance matrix, which represents the noise size and uncertainty in the observation process; is the transpose of the observation matrix.

7. A satellite search method for a ground terminal according to claim 5, characterized in that: The position of the satellite in the master device coordinate system is calculated by using a least squares algorithm, and the formula of the least squares algorithm includes: in, is the satellite position calculated by the master device; x satellite represents the position vector of the satellite in three-dimensional space, which is the target to be solved; N is the number of devices involved in the calculation, indicating the amount of signal data; x i is the position of the ith slave device; d i is the distance from device i to the satellite; ∥x i -x satellite ∥ is the estimated distance from device i to the satellite.

8. A satellite search method for a ground terminal according to claim 5, characterized in that: After the position of the satellite in the master device coordinate system is known, the relative angles between the master device antenna and the slave device antenna and the satellite are adjusted according to the position of the satellite in the master device coordinate system.

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