A satellite search system and method for a ground terminal

Abstract

The application relates to the technical field of satellite communication, and discloses a satellite searching system and method of a ground terminal, the system comprising: a master device with a first antenna and a second antenna, the first antenna being used for communication with a slave device, and the second antenna being used for receiving a low-orbit satellite beacon signal; the slave device with a first antenna and a second antenna, the first antenna being used for communication with the master device, and the second antenna being used for receiving a satellite beacon signal; a synchronization module used for synchronizing the clocks of the master device and the slave device; and a master device calculation module used for calculating the position of a satellite in a master device coordinate system in combination with the position of the slave device. According to the application, the first antenna is used to realize the intercommunication between the master device and the slave device, the time stamp data of the slave device is used, the master device calculates the accurate position of the satellite according to the time difference and the position, and the positioning problem when ephemeris information is lost or cannot be updated in real time is solved.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, specifically to a satellite search system and method for a ground terminal. Background Technology

[0002] In modern satellite communication systems, communication between ground terminals and satellites requires precise satellite position data. Typically, satellite position is obtained through ephemeris data (such as TLE data or real-time ephemeris data). Ephemeris provides orbital information of the satellite, allowing ground terminals to calculate the satellite's precise position and, based on this, transmit and receive signals.

[0003] However, obtaining accurate ephemeris data can be limited in certain situations, especially when real-time ephemeris data is unavailable or satellite orbit information cannot be updated in real time. In this context, traditional satellite positioning systems may be affected by problems such as communication interruptions, loss of ephemeris information, or delayed updates, resulting in ground terminals being unable to accurately obtain the satellite's position. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a satellite search system and method for ground terminals, which solves the problem that ground terminals cannot accurately obtain satellite positions when real-time ephemeris data is unavailable or satellite orbit information cannot be updated in a timely manner.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a satellite search system for a ground terminal, comprising:

[0006] The master device has a first antenna and a second antenna. The first antenna is used to communicate with the slave device, and the second antenna is used to receive low-Earth orbit satellite beacon signals.

[0007] The slave device has a first antenna and a second antenna. The first antenna is used to communicate with the master device, and the second antenna is used to receive satellite beacon signals and transmit the satellite beacon signals to the master device through the first antenna.

[0008] The synchronization module is used to synchronize the clocks of the master device and the slave device;

[0009] The master device calculation module calculates the satellite's position in the master device's coordinate system based on the time difference between the satellite beacon signals received by the synchronized slave device and the position of the slave device.

[0010] Preferably, 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.

[0011] Preferably, the main device further includes a signal processing module for preprocessing the satellite beacon signals transmitted from the slave device and transmitting them to the main device's computing module. The preprocessing includes:

[0012] The noise reduction unit is used to remove environmental noise from the received satellite beacon signals;

[0013] The enhancement unit is used to enhance the received satellite beacon signals.

[0014] Preferably, the system further includes an antenna beam pointing module for adjusting the second antenna pointing of the master and slave devices according to the position of the satellite in the master device coordinate system.

[0015] A satellite acquisition method for a ground terminal includes the following steps:

[0016] Deploy master and slave devices and establish communication connections between them;

[0017] The device receives satellite beacon signals, records the signal reception time, and transmits the data to the main device.

[0018] The master device calculates the satellite's position in the master device's coordinate system based on the satellite's beacon signal and signal reception time.

[0019] Preferably, there are several slave devices, and these slave devices perform clock synchronization after communicating with the master device. The time synchronization uses a Kalman filter algorithm.

[0020]

[0021] Among them, K k P is the Kalman gain; k-1 Let H be the covariance matrix of the estimation error at the previous time step, representing the degree of estimation error at the previous time step; k R is the observation matrix; k The observation noise covariance matrix represents the magnitude and uncertainty of noise during the observation process; This is the transpose of the observation matrix.

[0022] Preferably, the position of the satellite in the main equipment coordinate system is calculated using a least squares algorithm, the formula of which includes:

[0023]

[0024] in, It is the satellite position calculated by the main equipment; x satellite The position vector of the satellite in three-dimensional space represents the target to be solved; N is the number of devices involved in the calculation, representing the amount of signal data; xi It is the position of the i-th slave device; d i It is the distance from device i to the satellite; ∥x i -x satellite ∥ is the estimated distance from device i to the satellite.

[0025] Preferably, 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.

[0026] This invention provides a satellite search system and method for a ground terminal. It has the following beneficial effects:

[0027] 1. This invention enables communication between the master and slave devices via a first antenna. The satellite's position is then calculated based on the signal received by the slave device and the time difference between receptions, achieving the technical effect of accurately calculating the satellite's position even when ephemeris data is unavailable. Through the collaboration of the master device and multiple slave devices, utilizing the timestamps of the satellite beacon signals received by the slave devices, the master device can calculate the satellite's precise position based on the time difference and the device's location. Compared to existing technologies that rely on ephemeris data for positioning, this invention effectively solves the problem of being unable to locate satellites when ephemeris information is lost or cannot be updated in real time, through the collaboration of slave devices and time-series analysis.

[0028] 2. This invention improves the accuracy of satellite positioning calculations by introducing multi-device collaboration and a Kalman filter clock synchronization algorithm to ensure high-precision clock synchronization between multiple slave devices and the master device. Through the Kalman filter algorithm, the master device can optimize clock synchronization based on time differences between slave devices, reducing the impact of clock deviations on the signal. Compared to existing technologies where signal processing deviations may occur due to clock synchronization errors, this invention improves synchronization accuracy, ensures accurate signal reception, and thus enhances the reliability of satellite positioning calculations.

[0029] 3. This invention significantly improves the quality of received signals by denoising and enhancing satellite beacon signals. Through denoising and signal enhancement processing, the effects of environmental noise and signal attenuation are eliminated, ensuring data accuracy during satellite positioning. Compared to existing technologies that fail to adequately address signal noise and weak signal issues, this invention significantly reduces noise interference through signal processing techniques, ensuring more stable and clearer signal reception and greatly improving positioning accuracy.

[0030] 4. This invention achieves stable satellite signal reception by adjusting the antenna's pointing angle based on the satellite's position in the master device's coordinate system. After calculating the satellite's azimuth and elevation angles, the antennas of both the master and slave devices can automatically adjust to ensure they always point towards the satellite, maximizing signal reception quality. Compared to existing technologies where antenna positioning errors are large or require manual adjustment, this invention, through its automated antenna adjustment process, not only improves signal reception efficiency but also ensures stability and efficiency during communication, solving the delay and inaccuracy problems that may exist when manually adjusting the antenna in traditional methods. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the system architecture of the present invention;

[0032] Figure 2 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0033] 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.

[0034] To better understand the present invention, the above content will be described in detail below with reference to specific embodiments.

[0035] Please see the appendix Figure 1 This invention provides a satellite search system for a ground terminal, comprising:

[0036] The main device has a first antenna and a second antenna. The first antenna is used to communicate with the slave device, and the second antenna is used to receive low-Earth orbit satellite beacon signals.

[0037] The slave device has a first antenna and a second antenna. The first antenna is used to communicate with the master device, and the second antenna is used to receive satellite beacon signals and transmit the satellite beacon signals to the master device through the first antenna.

[0038] In this embodiment, the satellite search system of the ground terminal includes a master device and a slave device. The master device and the slave device are interconnected wirelessly through a first antenna. Specifically, the master device is equipped with two antennas. The first antenna is used for data communication with the slave device and is responsible for exchanging positioning information, synchronization data and other system status information. The second antenna is specifically used to receive beacon signals from low-orbit satellites and to receive positioning signals from satellites for subsequent positioning and signal processing.

[0039] The slave device is also equipped with two antennas. The first antenna is used for communication with the master device, ensuring efficient transmission of data and signals. The second antenna is used to receive beacon signals transmitted by the satellite to obtain the satellite's position information. When the slave device receives a satellite beacon signal, it records the reception time and transmits this signal data to the master device via the first antenna. Based on the satellite signal and time information received by the slave device, and combined with the relative positions of each device, the master device calculates the satellite's specific position in the master device's coordinate system.

[0040] The synchronization module is used to synchronize the clocks of the master device and the slave device;

[0041] In this embodiment, the synchronization module is used for clock synchronization between the master and slave devices. Since the master and slave devices need to work together to receive satellite beacon signals and process data in the satellite search system of the ground terminal, the clock accuracy between the devices is crucial to the accuracy and stability of the entire system.

[0042] The synchronization module avoids errors in signal reception and position calculation caused by clock skew. Specifically, clock synchronization can be achieved in various ways, such as using existing synchronization protocols, external synchronization signal sources, or clock correction through software algorithms. The most common implementation method is to use the Kalman filter algorithm to estimate and optimize the clock differences between devices, thereby adjusting the clock synchronization accuracy of the devices.

[0043] In some embodiments, the synchronization module can also dynamically correct clock errors based on real-time communication and signal reception times between devices, so that the system always maintains a high-precision time synchronization state, thereby providing a reliable data foundation for subsequent signal processing and positioning calculations.

[0044] The master device calculation module calculates the satellite's position in the master device's coordinate system based on the time difference between the satellite beacon signals received by the synchronized slave device and the position of the slave device.

[0045] In this embodiment, the master device calculation module is used to calculate the satellite's position in the master device coordinate system based on the time difference between the satellite beacon signal received by the slave device and the position of the slave device.

[0046] Specifically, the master device's calculation module first relies on the synchronized signal time data, using the time difference between the satellite beacon signals received by the slave devices (i.e., the time difference between the signals received by different devices) to determine the signal propagation delay. Since the clocks of the master and slave devices are precisely aligned through the synchronization module, the master device can accurately obtain and utilize the timestamps of the signals received by each slave device, thereby performing precise time difference calculations.

[0047] Next, combining the known location data from the slave devices, the master device's calculation module uses triangulation principles or other positioning algorithms to perform satellite positioning based on the time difference and location information between the devices. By calculating the satellite signal propagation time and the relative positions between the devices, the master device can determine the satellite's precise position. This calculation process may involve consideration of the signal propagation speed (such as the speed of light) and the distance between the devices.

[0048] In some embodiments, the master device's calculation module uses algorithms such as least squares and Kalman filtering to optimize the calculation of satellite positions. These algorithms improve the accuracy of satellite positioning by reducing the error between the predicted position and the actual received signal time difference. Ultimately, the calculation results provide the satellite's position in the master device's coordinate system and provide data support for subsequent operations such as antenna adjustment and communication optimization.

[0049] Through this calculation module, the main equipment can not only calculate the satellite's position based on 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.

[0050] Please see the appendix Figure 2 This invention also provides a satellite search method for a ground terminal, comprising the following steps:

[0051] Deploy master and slave devices and establish communication connections between them;

[0052] In this embodiment, the satellite search method of the ground terminal includes deploying master and slave devices and establishing a communication connection between them. Specifically, the master and slave devices establish a connection through wireless communication technology to ensure that they can exchange signals and data in real time. Through this communication connection, the master and slave devices can work in coordination to jointly complete tasks such as satellite signal reception, clock synchronization, signal processing, and satellite positioning.

[0053] In some embodiments, the communication connection between the master device and the slave device can use radio frequency bands or other suitable communication methods, such as Wi-Fi, Bluetooth, LoRa, Zigbee, etc., selecting the appropriate communication method according to the needs of the actual application scenario. Through wireless communication, the master device can receive timestamp data of satellite beacon signals from the slave device and perform processing such as signal synchronization, noise reduction, and enhancement. Simultaneously, the slave device can promptly feed back the received signal information to the master device, ensuring data accuracy and real-time performance.

[0054] Furthermore, the communication connection between the master and slave devices is not limited to data transmission. They can also maintain clock consistency through a signal synchronization mechanism, ensuring that each device receives satellite beacon signals at highly synchronized times, avoiding signal delay errors caused by clock asynchrony. In particular, the communication connection is a crucial element of this embodiment; the cooperation and coordination between the master and slave devices are the foundation for the efficient operation of the entire satellite search system.

[0055] In practice, the master device, through a wireless communication connection with the slave device, can not only acquire the slave device's signal reception time and other relevant data, but also perform satellite positioning calculations based on the received satellite beacon signals and timestamp information when necessary. During the master device's satellite position calculation, the calculation results are further optimized based on the slave device's position information, signal reception time, and synchronization time difference, thereby improving the accuracy of satellite positioning.

[0056] To ensure accurate signal transmission, encryption and data integrity checks may be implemented during the communication connection process to guarantee the security and reliability of the communication channel between the master and slave devices. In some embodiments, the communication connection may also support remote configuration and upgrades, thereby further enhancing the system's flexibility and adaptability.

[0057] Specifically, the process of establishing a communication connection includes the following steps:

[0058] The master and slave devices initialize the wireless communication channel through frequency band selection, channel access, and other methods.

[0059] The master and slave devices negotiate to determine the communication protocol and initiate the data transmission process to ensure that the slave device can transmit signal data to the master device.

[0060] After the communication connection is established, the master device and the slave device can synchronize clocks, exchange data, and update status information in real time during subsequent signal processing.

[0061] In some embodiments, the implementation of the communication connection may vary depending on the environment. For example, in complex environments, it may be necessary to enhance signal transmission capabilities, or in situations where the communication distance is long, a low-power, long-distance communication method may be required.

[0062] Therefore, through the communication connection between the master and slave devices, the system can maintain efficient collaboration during signal reception, processing, and satellite positioning. This implementation not only ensures that the slave device can transmit satellite beacon signals to the master device in real time, but also ensures that the master device can calculate the precise position of the satellite using an accurate clock synchronization, providing reliable data support for subsequent satellite positioning.

[0063] The device receives satellite beacon signals, records the signal reception time, and transmits the data to the main device.

[0064] In this embodiment, the satellite search method of the ground terminal includes receiving satellite beacon signals from a slave device and recording the signal reception time, and then transmitting this signal time information to a master device for further processing. Specifically, the system obtains timestamp information by receiving satellite beacon signals from the slave device, and sends this data to the master device for position calculation via a communication connection.

[0065] In some embodiments, the slave device receives beacon signals transmitted by low-Earth orbit satellites via a second antenna. These satellite beacon signals contain satellite positioning information, and the slave device records the time of signal reception upon receiving them. This timestamp data is crucial for subsequent satellite positioning calculations and is typically recorded in a high-precision time-synchronized manner to ensure signal accuracy and timing consistency.

[0066] Specifically, the timestamp data records the precise moment when the device receives the satellite beacon signal, which is recorded relative to the system's synchronized time base. Each slave device generates a corresponding timestamp based on the time it receives the satellite beacon signal and transmits this time information to the master device via the first antenna.

[0067] The transmission of signal timestamp data is accomplished through wireless communication technology. Specifically, the slave device sends signal time information and any other relevant data (such as received signal strength, error correction values, etc.) to the master device via its first antenna. Upon receiving this signal information from the slave device, the master device can calculate the satellite's precise position based on the time difference and location information between the slave devices.

[0068] In one possible implementation, communication between the slave and master devices may be based on protocols such as Wi-Fi, Bluetooth, LoRa, and other wireless communication technologies to ensure effective data transmission and synchronization. To avoid interference or data loss during signal transmission, the communication process may include encryption, verification, and other means to ensure data reliability and security.

[0069] Furthermore, with multiple slave devices configured, the master device can perform positioning calculations based on satellite beacon signals received from multiple slave devices, thereby improving the accuracy of the calculation results. However, due to potential clock deviations between different devices, the timestamps of signal reception may differ, which can affect the accuracy of the positioning calculations. Therefore, it is necessary to estimate and optimize the clock synchronization error between the master and slave devices to ensure that all devices process signal data within a unified time frame.

[0070] Specifically, the clock synchronization process is as follows:

[0071] The goal of clock synchronization is to transmit the time data of each slave device to the master device after receiving satellite beacon signals and recording the reception time. To ensure consistency of signal data between the master and slave devices, clock synchronization is necessary. The clock difference between the master and slave devices is estimated and progressively optimized using a Kalman filter algorithm, thereby guaranteeing that the master and slave devices operate synchronously on the same time base.

[0072] The Kalman filter algorithm is used to estimate and correct clock skew between devices based on the signal reception timestamps recorded by the devices and the location information between the devices. Specifically, the Kalman filter can dynamically adjust the clock synchronization value through a feedback mechanism of prediction and measurement to reduce error accumulation and improve synchronization accuracy.

[0073] In the Kalman filter algorithm, the Kalman gain K k The calculation formula is:

[0074]

[0075] Among them, K k P is the Kalman gain; k-1 Let H be the covariance matrix of the estimation error at the previous time step, representing the degree of estimation error at the previous time step; k R is the observation matrix; k The observation noise covariance matrix represents the magnitude and uncertainty of noise during the observation process; This is the transpose of the observation matrix.

[0076] Using the Kalman filter 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 and slave devices.

[0077] In some embodiments, Kalman filtering is not limited to simple time synchronization; it can also estimate the relative positions of devices and signal propagation delays, further improving the accuracy of signal processing. Through this state estimation, Kalman filtering can help the master device adapt to changes in clock skew in dynamic environments, thereby maintaining high-precision clock synchronization.

[0078] Therefore, by dynamically adjusting the clock synchronization error between the master and slave devices, it can be ensured that all devices in the ground terminal satellite search system operate under the same time reference. Through the Kalman filter algorithm, the system can efficiently estimate clock deviations, optimize synchronization accuracy, and provide high-quality time data for subsequent satellite positioning calculations.

[0079] In some embodiments, after the satellite beacon signal transmitted from the device is transmitted to the master device, it can be further denoised and enhanced, specifically including:

[0080] Noise Reduction: Satellite signals are often subject to interference, leading to a decline in signal quality. Accurately processing signal noise and restoring the true signal is crucial for improving positioning accuracy. Therefore, Bayesian inference methods are used to estimate noise in the signal. Bayesian inference effectively removes noise by combining prior knowledge with real-time data to update the signal's probability distribution.

[0081] The Bayesian inference model is as follows:

[0082]

[0083] Where θ represents the latent parameters of the signal; x m P(θ) represents the received signal; P(x) represents the prior probability distribution; P(x) represents the received signal. m |θ) is the likelihood function; P(x) m ) is the standardization constant; P(θ|x m ) represents the posterior probability.

[0084] Therefore, by using Bayesian inference methods, noise suppression of the signal can be achieved, resulting in higher signal quality and providing more accurate data for subsequent satellite positioning.

[0085] Enhancement: This unit enhances the received satellite beacon signals. Satellite beacon signals typically propagate through the air to ground receiving equipment, but during propagation, signal strength may weaken due to distance, environmental interference, or signal attenuation, thus affecting positioning accuracy and system stability. Therefore, the enhancement unit performs enhancement processing upon receiving the satellite beacon signal to improve its quality and strength.

[0086] Signal enhancement typically includes the following aspects: Power amplification: When the received satellite beacon signal is weak, gain control may be insufficient to meet system requirements. In this case, the enhancement unit can further amplify the signal power through power amplification technology. Power amplifiers can effectively enhance signal strength by increasing signal power, especially in environments with long distances or significant signal attenuation, ensuring stable signal transmission;

[0087] Multipath interference suppression: During satellite signal propagation, reflections or refractions may occur, leading to multipath effects and signal interference. The enhancement unit utilizes multipath effect suppression techniques to reduce the impact of reflected signals on the received signal. By synthesizing and correcting multiple received signals using algorithms, the enhancement unit can effectively recover the original signal and improve signal accuracy.

[0088] Therefore, through enhancement processing, the enhancement unit can significantly improve the quality of the received satellite beacon signal, increase signal strength, and improve the signal-to-noise ratio. The combination of these technologies ensures signal accuracy and stability, reducing 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 efficient system operation and achieving the desired positioning accuracy.

[0089] The master device calculates the satellite's position in the master device's coordinate system based on the satellite's beacon signal and signal reception time.

[0090] In this embodiment, the master device calculates the satellite's position in its coordinate system based on the received satellite beacon signal and its reception time. To ensure accurate satellite positioning, the master device relies on the signal data and timestamp information provided by the slave device, combined with the slave device's position, to calculate the satellite's precise location.

[0091] Specifically, satellite beacon signals contain distance information between the satellite and the receiving equipment, while 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. Combining this with the position information of the slave devices, the master device can use mathematical methods such as triangulation or least squares to calculate the precise position of the satellite in three-dimensional space.

[0092] Specifically, the calculation process of the master device includes the following steps:

[0093] Signal reception and time recording: Upon receiving a satellite beacon signal, the slave device records the signal reception time. This time is recorded relative to a known reference time in the master device's coordinate system. This timestamp information is used by the master device to calculate the signal propagation delay and further to calculate the satellite's relative position.

[0094] Calculation of signal propagation time: The timestamp T of each satellite signal received from the device. i This represents the time it takes for the signal to travel from the satellite to the device. According to the formula:

[0095] d i =c·(T) i -T0);

[0096] Where, d i is the distance from device i to the satellite; c represents the speed of signal propagation; T i T1 is the timestamp of the satellite beacon signal received from device i; T0 is the system reference time, which serves as a time reference.

[0097] Positioning is achieved by combining the locations of slave devices: Once the master device collects timestamp information and corresponding signal reception time differences from multiple slave devices, it can use this information to estimate the satellite's position. Specifically, the master device will use the known location information and distances of the slave devices, and perform optimized calculations using triangulation or least squares methods to deduce the satellite's spatial position.

[0098] For data from multiple slave devices, the master device can calculate the satellite position using the following least squares algorithm:

[0099] in, It is the satellite position calculated by the main equipment; x satellite The position vector of the satellite in three-dimensional space represents the target to be solved; N is the number of devices involved in the calculation, representing the amount of signal data; x i It is the position of the i-th slave device; d i It is the distance from device i to the satellite; ∥x i -x satellite ∥ is the estimated distance from device i to the satellite.

[0100] By minimizing the difference between the estimated distance and the actual measured distance of each slave device, the master device is able to determine the optimal position of the satellite.

[0101] Therefore, the master device uses the satellite beacon signal and signal reception time provided by the slave device, combined with the slave device's position data, and employs mathematical algorithms such as the least squares method to calculate the satellite's position in the master device's coordinate system. Through these steps, the master device can accurately locate the satellite's position, improving positioning accuracy and system stability.

[0102] After the master device calculates the satellite's position in the master device's coordinate system, it will adjust the relative angle between the master device antenna and the slave device antenna and the satellite according to the satellite's position to ensure that the antennas point to the satellite, thereby achieving stable and efficient satellite-to-ground communication.

[0103] Specifically, antenna adjustment is achieved by precisely calculating the antenna's pointing angle. Based on the satellite's position in the master device's coordinate system, the master device calculates the specific direction the antenna needs to point and adjusts the antennas of both the master and slave devices to ensure they are accurately aligned with the satellite. This adjustment process includes, but is not limited to, adjusting the azimuth and elevation angles to ensure the antenna can receive signals from the satellite, while simultaneously improving communication quality and positioning accuracy.

[0104] Among these steps, satellite position determination involves the master device calculating the satellite's position in the master device's coordinate system based on the received satellite beacon signal and the signal reception time of the slave device. This location is typically represented in three-dimensional coordinates, including the satellite's x, y, and z coordinates in space. Specifically, the satellite's position is derived by calculating distance information and position data from multiple slave devices.

[0105] Antenna angle calculation: To calculate the relative angle required for antenna adjustment, it is first necessary to know the satellite's position and the antenna's initial orientation. This is based on the satellite's three-dimensional coordinates x... satellite ,y satellite ,z satellite This allows us to calculate the relative angles between the master and slave device antennas and the satellite. These angles typically include azimuth and elevation.

[0106] The formula for calculating the azimuth angle θ is:

[0107]

[0108] Among them, y satellite and x satellite These are the components of the satellite's position on the y and x axes, respectively, and the azimuth angle θ represents the horizontal angle from the antenna reference direction (usually north or a certain reference direction) to the satellite.

[0109] The formula for calculating the elevation angle φ is:

[0110]

[0111] Among them, z satellite It represents the vertical component of the satellite's position, while the elevation angle φ represents the vertical angle at which the antenna points towards the satellite.

[0112] By calculating these two angles, the antennas of the master and slave devices can be precisely adjusted relative to the satellite.

[0113] Antenna adjustment process: Once the azimuth and elevation angles are calculated, the antennas of both the master and slave devices can be adjusted by modifying their mechanical structures or electronic control systems to align the antennas with the calculated directions. Specific adjustment methods may involve the following steps:

[0114] The rotation mechanism of the master and slave antennas typically includes an electric motor or servo system, which can adjust the antenna pointing according to the calculated angle.

[0115] By precisely adjusting the azimuth and elevation angles, the antenna's maximum gain direction is aligned with the satellite's position, thereby achieving optimal signal reception and transmission performance.

[0116] Adjustment and Optimization: In some embodiments, antenna adjustment may involve continuous, small-amplitude adjustments. Whenever the satellite position changes (e.g., due to changes in the satellite's orbit), the master equipment recalculates and adjusts the antenna pointing based on the new satellite position. This process ensures that the antenna always maintains optimal alignment with the satellite, especially in low Earth orbit (LEO) satellite applications where the relative positions between the satellite and ground equipment change rapidly, requiring frequent antenna pointing optimization.

[0117] Therefore, the master device calculates the azimuth and elevation angles required for antenna adjustment based on the satellite position, and then adjusts the antennas of both the master and slave devices to point towards the satellite using these angles. This precise antenna adjustment method ensures stable reception of satellite signals, improving communication quality and positioning accuracy. In dynamically changing environments, real-time antenna adjustment is crucial for ensuring the efficient operation of the system.

[0118] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A satellite search system for a ground terminal, characterized in that, include: The master device has a first antenna and a second antenna. The first antenna is used to communicate with the slave device, and the second antenna is used to receive low-Earth orbit satellite beacon signals. The slave device has a first antenna and a second antenna. The first antenna is used to communicate with the master device, and the second antenna is used to receive satellite beacon signals and transmit the satellite beacon signals to the master device through the first antenna. The synchronization module is used to synchronize the clocks of the master device and the slave device; The master device calculation module calculates the satellite's position in the master device coordinate system based on the time difference between the satellite beacon signals received by the synchronized slave device and the position of the slave device. The synchronization module includes a Kalman filter algorithm unit, used to estimate and optimize the clock synchronization error between the master device and the slave device; The system comprises several slave devices, and these slave devices perform clock synchronization after communicating with the master device. The time synchronization uses a Kalman filter algorithm. ； in, Kalman gain; Let be the covariance matrix of the estimation error at the previous time step, representing the degree of estimation error at the previous time step; The observation matrix; The observation noise covariance matrix represents the magnitude and uncertainty of noise during the observation process; This is the transpose of the observation matrix.

2. The satellite search system for a ground terminal according to claim 1, characterized in that, The main device also includes a signal processing module for preprocessing the satellite beacon signals transmitted from the slave device and transmitting them to the main device's computing module. The preprocessing includes: The noise reduction unit is used to remove environmental noise from the received satellite beacon signals; The enhancement unit is used to enhance the received satellite beacon signals.

3. The satellite search system for a ground terminal according to claim 1, characterized in that, The system also includes an antenna beam pointing module, which is used to adjust the second antenna pointing of the master and slave devices according to the position of the satellite in the master device coordinate system.

4. A satellite search method for a ground terminal, based on a satellite search system for a ground terminal according to any one of claims 1-3, characterized in that, Includes the following steps: Deploy master and slave devices and establish communication connections between them; The device receives satellite beacon signals, records the signal reception time, and transmits the data to the main device. The master device obtains the time difference between the satellite beacon signal received by the slave device and the signal reception time based on the satellite beacon signal and the position of the slave device to calculate the position of the satellite in the master device's coordinate system.

5. A satellite search method for a ground terminal according to claim 4, characterized in that, The system comprises several slave devices, and these slave devices perform clock synchronization after communicating with the master device. The time synchronization uses a Kalman filter algorithm. ； in, Kalman gain; Let be the covariance matrix of the estimation error at the previous time step, representing the degree of estimation error at the previous time step; The observation matrix; The observation noise covariance matrix represents the magnitude and uncertainty of noise during the observation process; This is the transpose of the observation matrix.

6. A satellite search method for a ground terminal according to claim 4, characterized in that, The position of the satellite in the main equipment coordinate system is calculated using the least squares algorithm, the formula of which includes: ； in, It is the satellite position calculated by the main equipment; This represents the satellite's position vector in three-dimensional space, which is the target to be solved; N is the number of devices involved in the calculation, representing the amount of signal data; It is the position of the i-th slave device; It is the distance from device i to the satellite; It is the estimated distance from device i to the satellite.

7. A satellite search method for a ground terminal according to claim 4, characterized in that, Once the satellite's position in the master equipment coordinate system is known, the relative angles between the master equipment antenna and the slave equipment antenna and the satellite are adjusted according to the satellite's position in the master equipment coordinate system.

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