A method for capturing and tracking low-orbit satellites based on VICTS antenna

Abstract

The present invention provides a method for capturing and tracking low-orbit satellites based on a VICTS antenna, and belongs to the field of satellite search technology. The method uses a VICTS antenna to perform conical scanning to capture satellite signals based on the ephemeris data of the low-orbit satellite, and maps the conical scanning results of the VICTS antenna to a three-dimensional space to obtain a parabola of the antenna in the three-dimensional space, and then uses the gradient descent method to fit the parabola to determine the extreme points of the parabola; then the antenna pointing of the VICTS antenna is optimized and adjusted according to the extreme points of the parabola. Afterwards, trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated; the antenna pointing coordinate system is translated and transformed according to the coordinate system translation to obtain a new antenna pointing coordinate system. The present invention effectively eliminates the interference of high-speed satellite motion on the optimization process, can accurately fit the relationship between signal strength and antenna pointing, and improves the signal capture capability and tracking accuracy of low-orbit satellites.

Description

Technical Field

[0001] The present invention relates to the field of satellite search technology, and in particular to a low-orbit satellite capture and tracking method based on a VICTS antenna. Background Art

[0002] Traditional satellite communication systems mostly rely on high-orbit satellites (GEO). Although they have wide coverage and fixed orbital positions, they have problems such as large communication delays, limited spectrum resources and high costs, making it difficult to meet real-time communication and broadband data needs. In contrast, low-orbit satellite (LEO) communication systems achieve low latency, high spectrum utilization and seamless global coverage through the coordinated work of multiple satellites, which has significant advantages, especially in remote areas.

[0003] With the rapid development of low-orbit satellite communications, achieving accurate capture and stable tracking of high-speed moving satellites has become a key technical challenge. Traditional antenna systems often face the following two major problems when facing high-speed movement of low-orbit satellites:

[0004] 1. Interference of high-speed satellite motion on the optimization process

[0005] In the prior art, the antenna optimization process is easily affected by the high-speed movement of satellites. Due to the high dynamic characteristics of satellites, the signals change frequently, and the traditional method cannot adjust the antenna beam direction in time, resulting in the optimization result being closely related to the relative speed of the satellite. The resulting optimization error often leads to reduced signal strength or even communication interruption, which makes it difficult to meet the high stability requirements of low-orbit satellite communications.

[0006] 2. Low optimization efficiency and insufficient accuracy

[0007] Currently, antenna optimization mostly uses mechanical scanning or simple interpolation algorithms, and its inefficient two-dimensional processing method limits the optimization speed and accuracy. At the same time, due to the lack of efficient modeling and optimization methods for antenna radiation patterns, existing methods are difficult to quickly and accurately locate the strongest signal point, resulting in delayed antenna adjustment and affecting communication quality. Summary of the invention

[0008] In view of this, an embodiment of the present invention provides a low-orbit satellite capture and tracking method based on a VICTS antenna, so as to solve the problems that the existing satellite optimization technology has weak anti-interference ability, low optimization efficiency and low accuracy.

[0009] The technical solution adopted by the present invention is:

[0010] The present invention provides a low-orbit satellite capture and tracking method based on a VICTS antenna, comprising:

[0011] Based on the ephemeris data of the low-orbit satellite, the VICTS antenna is used to perform conical scanning to capture the satellite signal of the low-orbit satellite;

[0012] The conical scanning result of the VICTS antenna is mapped to three-dimensional space to obtain the parabola of the VICTS antenna pattern in three-dimensional space;

[0013] Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained, and based on the multiple three-dimensional coordinate points, the parabola is fitted using the gradient descent method to determine the extreme points of the parabola;

[0014] The adjustment amount of the VICTS antenna is calculated according to the extreme value point of the parabola, and the antenna pointing direction of the VICTS antenna is adjusted according to the adjustment amount;

[0015] Satellite trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated based on the satellite trajectory modeling results;

[0016] The antenna pointing coordinate system of the VICTS antenna is translated according to the coordinate system translation amount to obtain a new antenna pointing coordinate system.

[0017] Furthermore, the method of performing conical scanning using a VICTS antenna based on the ephemeris data of the low-orbit satellite to capture the satellite signal of the low-orbit satellite includes:

[0018] Initialize the VICTS antenna and obtain the ephemeris data of the low-orbit satellite after initialization;

[0019] The position of the low-orbit satellite is determined based on the ephemeris data, and the VICTS antenna is controlled to perform spiral conical scanning in the pitch angle and azimuth angle dimensions. After the satellite signal of the low-orbit satellite is captured, the satellite optimization mode is performed.

[0020] Furthermore, mapping the conical scanning result of the VICTS antenna to a three-dimensional space to obtain a parabola of the VICTS antenna pattern in the three-dimensional space includes:

[0021] The azimuth angle yaw scanned by the VICTS antenna is used as the x-axis, the pitch angle pitch is used as the y-axis, and the energy value power output by the beacon is used as the z-axis to construct a three-dimensional space coordinate system.

[0022] The conical scanning results of the VICTS antenna are transformed into coordinates and mapped into a three-dimensional space coordinate system to obtain the parabola corresponding to the VICTS antenna radiation pattern in three-dimensional space.

[0023] Furthermore, the method of acquiring a plurality of three-dimensional coordinate points by scanning with a VICTS antenna, and fitting a parabola based on the plurality of three-dimensional coordinate points by using a gradient descent method to determine the extreme value points of the parabola includes:

[0024] Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained to obtain a spatial point set ,in, i =1,2,...,N;

[0025] The parabola is represented by a parabola function:

[0026]

[0027] in, are all fixed coefficients of the parabolic function; x , y , z Respectively represent the parabola in x , y and z Coordinate values ​​in direction;

[0028] Define parabola translation , respectively, representing the parabola in x , y and z The translation in the direction allows the parabola to move in three-dimensional space, and a new translated parabola function is obtained:

[0029]

[0030] Define the cost function E of parabola fitting and calculate the parabola translation The partial derivative of , and the parabola translation is adjusted using the gradient descent method , minimize the cost function E of parabola fitting, so that the fitted parabola is closest to the actual collected spatial point set ;

[0031] By calculating the parabola translation amount through the cost function E The second derivative of the parabola gives the extreme point .

[0032] Further, calculating the adjustment amount of the VICTS antenna according to the extreme point of the parabola, and adjusting the antenna pointing direction of the VICTS antenna according to the adjustment amount, includes:

[0033] Set the scanning center coordinates of the current VICTS antenna and the extreme point of the parabola For comparison, calculate the adjustment amount of the VICTS antenna:

[0034]

[0035]

[0036]

[0037] in, , , Respectively represent the VICTS antenna x , y and z The amount of adjustment in direction;

[0038] According to the adjustment amount of the VICTS antenna, the scanning center point of the current VICTS antenna is adjusted toward the extreme point of the parabola, so that the VICTS antenna points to the direction where the satellite signal is the strongest.

[0039] Furthermore, the satellite trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated based on the satellite trajectory modeling result, including:

[0040] The elevation angle and azimuth angle of the low-orbit satellite are obtained by solving the ephemeris data of the low-orbit satellite;

[0041] The satellite trajectory is described using a 13th-order polynomial:

[0042]

[0043]

[0044] in, Indicates the elevation angle in the satellite trajectory; represents the azimuth in the satellite track; is the time variable; and are the polynomial coefficients, which are calculated using the ephemeris data of the low-orbit satellite;

[0045] The satellite trajectory is modeled according to the change information of the pitch angle and azimuth angle, and a trajectory prediction model that can predict the change of the low-orbit satellite trajectory is obtained;

[0046] The ephemeris data and time variables of the low-orbit satellite t The trajectory prediction model is input to predict the satellite trajectory of the low-orbit satellite, and the coordinate system translation is calculated based on the predicted satellite trajectory.

[0047] Furthermore, the step of performing a translation transformation on the antenna pointing coordinate system of the VICTS antenna according to the coordinate system translation amount to obtain a new antenna pointing coordinate system includes:

[0048] The calculated results of the elevation angle and azimuth angle in the satellite trajectory are used as the coordinate system translation, and the antenna pointing coordinate system of the VICTS antenna is adjusted by the translation matrix ( x, y ) to perform translation transformation to obtain a new antenna pointing coordinate system , the translation transformation process is expressed as: ; Indicates the elevation angle in the satellite trajectory; Represents the azimuth in the satellite track.

[0049] In summary, the beneficial effects of the present invention are as follows:

[0050] The present invention provides a method for capturing and tracking low-orbit satellites based on a VICTS antenna. The method adopts a parabola fitting method based on the gradient descent method, combines multiple three-dimensional coordinate points obtained during antenna scanning, and realizes efficient optimization of antenna pointing by optimizing the translation amount. It can more accurately fit the relationship between signal strength and antenna pointing, and ensure that the antenna can be adjusted to the position with the strongest signal in the shortest time, thereby improving the signal capture capability and tracking accuracy of the low-orbit satellite communication system. At the same time, the method translates the antenna pointing coordinate system according to the satellite trajectory, and removes the satellite's movement speed from the optimization calculation by translating the coordinate system, so that the optimization process is independent of the relative speed of the satellite. Regardless of how the satellite's trajectory changes, the system can continuously and stably track and optimize the signal strength, effectively eliminating the interference of the satellite's high-speed movement on the optimization process. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following is a brief introduction to the drawings required for use in the embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work, and these are all within the protection scope of the present invention.

[0052] Figure 1 A flow chart of a method for capturing and tracking low-orbit satellites based on a VICTS antenna according to the present invention;

[0053] Figure 2 This is a low-orbit satellite alignment flow chart of an embodiment of the present invention;

[0054] Figure 3 The figure is a flowchart of antenna optimization according to an embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. If there is no conflict, the various features of the present invention and the embodiments can be combined with each other, all within the scope of protection of the present invention.

[0056] Low-orbit satellites operate at high speeds, requiring efficient antenna tracking capabilities. Traditional electronic scanning antennas are costly and power-hungry, making it difficult to meet the needs of mobile terminals. The VICTS antenna based on mechanical control scanning has the advantages of low elevation angle, low profile, high directivity and low side lobes, making it suitable for low-orbit satellite applications. The VICTS antenna can achieve high-precision tracking when low-orbit satellites frequently switch by precisely adjusting the beam direction, and has strong anti-interference capabilities, significantly improving the stability and reliability of the communication link.

[0057] Therefore, the application of VICTS antenna in low-orbit satellite communications, with its simple structure, low cost and low power consumption, provides an ideal solution for low-orbit satellite communication systems and has broad application prospects.

[0058] In view of the problems existing in traditional antenna systems when facing the high-speed movement of low-orbit satellites, the present invention proposes two key technical solutions:

[0059] 1. Eliminate the interference of high-speed satellite movement on the optimization process

[0060] The present invention effectively eliminates the interference of high-speed satellite motion on the optimization process by translating the satellite's tracking coordinate system according to the ephemeris trajectory and dynamically adjusting the antenna pointing coordinate system using an accurate trajectory prediction model. Through this innovative coordinate system conversion method, the optimization result is no longer affected by the relative speed of the satellite, ensuring that the antenna beam can always be aligned with the direction of the strongest signal in a rapidly changing environment, greatly improving the stability of communication.

[0061] 2. Efficient three-dimensional parabola fitting method

[0062] The present invention proposes a three-dimensional parabola fitting method based on gradient descent, which maps the scanning results of the antenna into three-dimensional space: the azimuth angle is used as the x-axis, the pitch angle is used as the y-axis, and the energy value output by the beacon is used as the z-axis to form a three-dimensional vector in space. By collecting multiple three-dimensional coordinate points, the gradient descent method is used to optimize the fitting parabola and quickly find the extreme point with the strongest energy. This method overcomes the limitations of traditional two-dimensional optimization algorithms, significantly improves the efficiency and accuracy of antenna optimization, and provides efficient and stable technical support for low-orbit satellite communications. The detailed implementation process of the present invention is shown in the following embodiments.

[0063] Example 1: Reference Figure 1 As shown, Figure 1 This is a flow chart of a low-orbit satellite capture and tracking method based on a VICTS antenna of the present invention. Figure 1 As shown, a low-orbit satellite capture and tracking method based on a VICTS antenna of the present invention is applied to a low-orbit satellite communication system, and the method includes:

[0064] Based on the ephemeris data of the low-orbit satellite, the VICTS antenna is used to perform conical scanning to capture the satellite signal of the low-orbit satellite;

[0065] The conical scanning result of the VICTS antenna is mapped to three-dimensional space to obtain the parabola of the VICTS antenna pattern in three-dimensional space;

[0066] Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained, and based on the multiple three-dimensional coordinate points, the parabola is fitted using the gradient descent method to determine the extreme points of the parabola;

[0067] The adjustment amount of the VICTS antenna is calculated according to the extreme value point of the parabola, and the antenna pointing direction of the VICTS antenna is adjusted according to the adjustment amount;

[0068] Satellite trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated based on the satellite trajectory modeling results;

[0069] The antenna pointing coordinate system of the VICTS antenna is translated according to the coordinate system translation amount to obtain a new antenna pointing coordinate system.

[0070] Further, in an embodiment of the present invention, based on the ephemeris data of the low-orbit satellite, a VICTS antenna is used to perform conical scanning to capture the satellite signal of the low-orbit satellite, which specifically includes the following process:

[0071] Initialize the VICTS antenna and obtain the ephemeris data of the low-orbit satellite after initialization;

[0072] The position of the low-orbit satellite is determined based on the ephemeris data, and the VICTS antenna is controlled to perform spiral conical scanning in the pitch angle and azimuth angle dimensions. After the satellite signal of the low-orbit satellite is captured, the satellite optimization mode is performed.

[0073] In the embodiment of the present invention, when capturing and tracking a low-orbit satellite, it is necessary to complete the low-orbit satellite alignment process. Figure 2 As shown, the process flow of the present invention starts a series of initialization processes after the communication system is powered on and reset, including operations such as antenna dish zeroing calibration (i.e., zeroing). After the initialization is completed, the system performs spiral conical scanning in the two dimensions of pitch angle and azimuth angle according to the ephemeris data of the low-orbit satellite (such as inertial navigation attitude and coordinate system rotation). The scanning process determines whether the satellite signal is captured. If the satellite signal is not captured, the conical scan is performed again. After successfully capturing the satellite signal, the system enters the optimization mode to adjust the antenna pointing in real time to ensure the maximum signal strength. If the signal is interrupted or lost during the tracking process, the system will automatically switch back to the scanning mode to recapture the signal.

[0074] Furthermore, in an embodiment of the present invention, the conical scanning result of the VICTS antenna is mapped to a three-dimensional space to obtain a parabola of the VICTS antenna pattern in the three-dimensional space, which specifically includes the following process:

[0075] The azimuth angle yaw scanned by the VICTS antenna is used as the x-axis, the pitch angle pitch is used as the y-axis, and the energy value power output by the beacon is used as the z-axis to construct a three-dimensional space coordinate system.

[0076] The conical scanning results of the VICTS antenna are transformed into coordinates and mapped into a three-dimensional space coordinate system to obtain the parabola corresponding to the VICTS antenna radiation pattern in three-dimensional space.

[0077] In the embodiment of the present invention, after entering the optimization mode, it is necessary to control the VICTS antenna to point to the direction with the strongest satellite signal. Figure 3 The antenna optimization process shown first obtains the real-time pointing of the antenna (i.e., the pitch angle and yaw angle), and performs coordinate conversion according to the ephemeris data, and simultaneously performs beacon energy (power) detection. In the present invention, the antenna's directional pattern presents a three-dimensional parabola shape in space. In order to achieve accurate signal optimization, the present invention uses the azimuth angle (yaw) of the antenna scan as the x-axis, the pitch angle (pitch) as the y-axis, and the energy value (power) output by the beacon as the z-axis to form a three-dimensional space vector, and constructs a three-dimensional space coordinate system. Since the antenna's directional pattern presents a parabola shape, the conical scanning result is a three-dimensional space vector in a circular queue. The conical scanning result of the VICTS antenna is mapped to the three-dimensional space coordinate system to obtain the parabola corresponding to the VICTS antenna directional pattern in three-dimensional space. After the three-dimensional space coordinate system is established, multiple three-dimensional coordinate points (i.e., a set of spatial points) are obtained by antenna scanning. ,in , and use the gradient descent method to fit the parabola in three-dimensional space, calculate the extreme value of the parabola, find the position with the strongest energy, and then control the antenna to point to this position (i.e. the extreme value point) for optimization.

[0078] Further, in an embodiment of the present invention, a plurality of three-dimensional coordinate points are obtained by scanning a VICTS antenna, and based on the plurality of three-dimensional coordinate points, a parabola is fitted using a gradient descent method to determine the extreme points of the parabola, specifically including:

[0079] Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained to obtain a spatial point set ,in, i =1,2,...,N;

[0080] The parabola is represented by a parabola function:

[0081]

[0082] in, are all fixed coefficients of the parabolic function; x , y , z Respectively represent the parabola in x , y and z Coordinate value in direction.

[0083] In order to achieve the translation of the parabola, the parabola translation is defined , respectively, representing the parabola in x , y and z The translation in the direction allows the parabola to move in three-dimensional space, and a new translated parabola function is obtained:

[0084]

[0085] In the parabola fitting process, the cost function E of the parabola fitting is defined, and the parabola translation is calculated at the same time. The partial derivative of , and the parabola translation is adjusted using the gradient descent method , in order to minimize the fitting error, that is, to minimize the cost function E of the parabola fitting, so that the fitted parabola is closest to the actual collected spatial point set .

[0086] Among them, the fitting cost function is:

[0087] .

[0088] In order to minimize the cost function , we translate the parabola Find the partial derivatives respectively.

[0089] The process of finding partial derivatives is as follows:

[0090] right The partial derivative of :

[0091]

[0092] right The partial derivative of :

[0093]

[0094] right The partial derivative of :

[0095]

[0096] in, expressz The spatial coordinate value after adjustment in the direction.

[0097] Through The partial derivatives of are calculated and the parabola translation is updated using the gradient descent method:

[0098]

[0099]

[0100]

[0101] in, is the learning rate, which controls the step size of each update, k Represents the number of iterations. Through iterative updates, the parabola translation that minimizes the error is finally obtained. , thus completing the parabola fitting.

[0102] By calculating the parabola translation amount through the cost function E The second derivative of the parabola gives the extreme point .

[0103] Specifically, after the parabola fitting is completed, the fitted parabola has a clear extreme point, which corresponds to the position where the signal energy is the strongest. Therefore, in order to achieve the best energy pointing of the antenna, the present invention needs to perform extreme value calculation and antenna pointing optimization.

[0104] Among them, since the fitted parabola function is a quadratic form, its extreme point can be obtained by solving the second-order derivative of the parabola function. In the present invention, the extreme point Represents the optimal position for the antenna to point to, and is calculated as follows:

[0105]

[0106] The parabola translation is calculated by the cost function E (ie error function) The second-order derivative of can be used to solve the extreme points of the parabola and determine the optimal antenna pointing direction.

[0107] In the embodiment of the present invention, the extreme point obtained by calculation , compare the current scanning center point with the extreme point to determine the direction and amplitude of antenna adjustment. Specifically, the coordinates of the current scanning center point Towards the extreme point Adjustments are made to optimize antenna pointing, which includes:

[0108] Set the scanning center coordinates of the current VICTS antenna and the extreme point of the parabola For comparison, calculate the adjustment amount of the VICTS antenna:

[0109]

[0110]

[0111]

[0112] in, , , Respectively represent the VICTS antenna x , y and z The amount of adjustment in the direction.

[0113] According to the adjustment amount of the VICTS antenna, the scanning center point of the current VICTS antenna is adjusted to the extreme point of the parabola, so that the VICTS antenna points to the direction where the satellite signal is strongest. According to this adjustment amount, the antenna direction is updated to gradually approach the extreme point, that is, the position where the signal is strongest.

[0114] The present invention adopts a parabola fitting method based on the gradient descent method, combines multiple three-dimensional coordinate points obtained during the antenna scanning process, and optimizes the parabola translation amount. Achieve efficient optimization of antenna pointing. Compared with the optimization method based on traditional algorithms commonly used in the prior art, the gradient descent fitting method of the present invention can more accurately fit the relationship between signal strength and antenna pointing, ensuring that the antenna can be adjusted to the position with the strongest signal in the shortest time, thereby improving the signal capture capability and tracking accuracy of the low-orbit satellite communication system. By fitting the parabola in three-dimensional space, the error is greatly reduced, avoiding signal loss caused by inaccurate fitting.

[0115] Furthermore, in the embodiment of the present invention, the antenna coordinate system and the satellite trajectory are both two-dimensional coordinate systems, which are described by azimuth (yaw) and pitch (pitch) respectively. In the process of low-orbit satellite tracking, through the translation transformation of the coordinate system, we can eliminate the influence of the high-speed movement of the satellite on the antenna optimization process and maintain the accuracy and stability of the antenna pointing. The embodiment of the present invention models the satellite trajectory based on the ephemeris data of the low-orbit satellite, and calculates the coordinate system translation amount based on the satellite trajectory modeling results. The process specifically includes:

[0116] The elevation angle and azimuth angle of the low-orbit satellite are obtained by calculating the ephemeris data of the low-orbit satellite.

[0117] A 13th-order polynomial is used to describe the satellite trajectory (i.e. the changes in the elevation angle and azimuth angle):

[0118]

[0119]

[0120] in, Indicates the elevation angle in the satellite trajectory; represents the azimuth in the satellite track; is the time variable; and are polynomial coefficients, which are calculated using the ephemeris data of low-orbit satellites and reflect the change of the satellite's position in orbit over time.

[0121] The satellite trajectory is modeled based on the change information of the pitch angle and azimuth angle, and a trajectory prediction model that can predict the change of the low-orbit satellite trajectory is obtained. The trajectory prediction model can predict the satellite trajectory of the low-orbit satellite based on the satellite ephemeris data and the time variable t.

[0122] Finally, the ephemeris data and time variables of the low-orbit satellite t The trajectory prediction model is input to predict the satellite trajectory of the low-orbit satellite, and the coordinate system translation is calculated based on the predicted satellite trajectory.

[0123] Among them, the coordinate system translation is calculated by the trajectory of the satellite, specifically:

[0124]

[0125] here, and Corresponding to the elevation angle and azimuth angle in the satellite trajectory, respectively, through the satellite ephemeris data and time t The input value is used and the calculated result is used as the specific coordinate system translation amount. x, y The original pointing coordinate system of the antenna is ( x, y ), Represents the coordinates after translation transformation.

[0126] Furthermore, in the embodiment of the present invention, the movement of the satellite causes the translation of the tracking coordinate system. In order to eliminate the influence of the movement of the satellite in the antenna pointing coordinate system, the embodiment of the present invention translates the antenna pointing coordinate system to a new reference system through a translation matrix. The original pointing coordinate system of the antenna is ( x, y ), the coordinates after translation transformation are The embodiment of the present invention performs a translation transformation on the antenna pointing coordinate system of the VICTS antenna according to the coordinate system translation amount to obtain a new antenna pointing coordinate system. The process specifically includes:

[0127] The calculated results of the elevation angle and azimuth angle in the satellite trajectory are used as the coordinate system translation, and the antenna pointing coordinate system of the VICTS antenna is adjusted by the translation matrix ( x, y) to perform translation transformation to obtain a new antenna pointing coordinate system , the translation transformation process is expressed as: .

[0128] The present invention effectively eliminates the interference of high-speed satellite motion on the optimization process by translating the satellite tracking coordinate system according to the ephemeris trajectory. When facing high-speed low-orbit satellites, traditional antenna systems are often affected by the relative motion speed of the satellite, resulting in poor signal capture and tracking effects. The present invention eliminates the satellite's motion speed from the optimization calculation by translating the coordinate system, making the optimization process independent of the satellite's relative speed. Regardless of how the satellite's trajectory changes, the system can continuously and stably track and optimize the signal strength. This innovative method significantly improves the reliability of low-orbit satellite communications and avoids the limitations of traditional methods that cannot adapt to high-speed satellite movements.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for capturing and tracking low-orbit satellites based on a VICTS antenna, characterized in that: include: Based on the ephemeris data of the low-orbit satellite, the VICTS antenna is used to perform conical scanning to capture the satellite signal of the low-orbit satellite; The conical scanning result of the VICTS antenna is mapped to three-dimensional space to obtain the parabola of the VICTS antenna pattern in three-dimensional space; Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained, and based on the multiple three-dimensional coordinate points, the parabola is fitted using the gradient descent method to determine the extreme points of the parabola; The adjustment amount of the VICTS antenna is calculated according to the extreme value point of the parabola, and the antenna pointing direction of the VICTS antenna is adjusted according to the adjustment amount; Satellite trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated based on the satellite trajectory modeling results; The antenna pointing coordinate system of the VICTS antenna is translated according to the coordinate system translation amount to obtain a new antenna pointing coordinate system.

2. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: The method of performing conical scanning using a VICTS antenna based on the ephemeris data of the low-orbit satellite to capture the satellite signal of the low-orbit satellite includes: Initialize the VICTS antenna and obtain the ephemeris data of the low-orbit satellite after initialization; The position of the low-orbit satellite is determined based on the ephemeris data, and the VICTS antenna is controlled to perform spiral conical scanning in the pitch angle and azimuth angle dimensions. After the satellite signal of the low-orbit satellite is captured, the satellite optimization mode is performed.

3. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: Mapping the conical scanning result of the VICTS antenna to the three-dimensional space to obtain the parabola of the VICTS antenna pattern in the three-dimensional space includes: The azimuth angle yaw scanned by the VICTS antenna is used as the x-axis, the pitch angle pitch is used as the y-axis, and the energy value power output by the beacon is used as the z-axis to construct a three-dimensional space coordinate system. The conical scanning results of the VICTS antenna are transformed into coordinates and mapped into a three-dimensional space coordinate system to obtain the parabola corresponding to the VICTS antenna radiation pattern in three-dimensional space.

4. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: The method of obtaining a plurality of three-dimensional coordinate points by scanning with a VICTS antenna, and fitting a parabola based on the plurality of three-dimensional coordinate points by using a gradient descent method to determine the extreme value points of the parabola includes: Through VICTS antenna scanning, multiple three-dimensional coordinate points are obtained to obtain a spatial point set ,in, i =1,2, ...,N; The parabola is represented by a parabola function: in, are all fixed coefficients of the parabolic function; x , y , z Respectively represent the parabola in x , y and z Coordinate values ​​in direction; Define parabola translation , respectively, representing the parabola in x , y and z The translation in the direction allows the parabola to move in three-dimensional space, and a new translated parabola function is obtained: Define the cost function E of parabola fitting and calculate the parabola translation The partial derivative of , and the parabola translation is adjusted using the gradient descent method , minimize the cost function E of parabola fitting, so that the fitted parabola is closest to the actual collected spatial point set ; By calculating the parabola translation amount through the cost function E The second derivative of the parabola gives the extreme point .

5. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: The step of calculating the adjustment amount of the VICTS antenna according to the extreme point of the parabola, and adjusting the antenna pointing direction of the VICTS antenna according to the adjustment amount includes: Set the scanning center coordinates of the current VICTS antenna and the extreme point of the parabola For comparison, calculate the adjustment amount of the VICTS antenna: in, , , Respectively represent the VICTS antenna x , y and z The amount of adjustment in direction; According to the adjustment amount of the VICTS antenna, the scanning center point of the current VICTS antenna is adjusted toward the extreme point of the parabola, so that the VICTS antenna points to the direction where the satellite signal is the strongest.

6. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: The satellite trajectory modeling is performed based on the ephemeris data of the low-orbit satellite, and the coordinate system translation is calculated based on the satellite trajectory modeling result, including: The elevation angle and azimuth angle of the low-orbit satellite are obtained by solving the ephemeris data of the low-orbit satellite; The satellite trajectory is described using a 13th-order polynomial: in, Indicates the elevation angle in the satellite trajectory; represents the azimuth in the satellite track; is the time variable; and are the polynomial coefficients, which are calculated using the ephemeris data of the low-orbit satellite; The satellite trajectory is modeled according to the change information of the pitch angle and azimuth angle, and a trajectory prediction model that can predict the change of the low-orbit satellite trajectory is obtained; The ephemeris data and time variables of the low-orbit satellite t The trajectory prediction model is input to predict the satellite trajectory of the low-orbit satellite, and the coordinate system translation is calculated based on the predicted satellite trajectory.

7. The low-orbit satellite capture and tracking method according to claim 1, characterized in that: The step of performing a translation transformation on the antenna pointing coordinate system of the VICTS antenna according to the coordinate system translation amount to obtain a new antenna pointing coordinate system includes: The calculated results of the elevation angle and azimuth angle in the satellite trajectory are used as the coordinate system translation, and the antenna pointing coordinate system of the VICTS antenna is adjusted by the translation matrix ( x, y ) to perform translation transformation to obtain a new antenna pointing coordinate system , the translation transformation process is expressed as: ; Indicates the elevation angle in the satellite trajectory; Represents the azimuth in the satellite track.

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