Method for searching electronic beam pointing of satellite communication hybrid tracking system

Abstract

The application discloses a satellite communication hybrid tracking system and an electronic beam pointing searching method thereof. The method comprises the following steps: performing mechanical adjustment and then performing electrical adjustment, so as to obtain equivalent dynamic electronic beam pointing. The electronic beam pointing is dynamically updated based on the deflection direction of a (mechanical) antenna of a user terminal and the incident path direction of a target satellite relative to the main axis direction of the antenna, so as to ensure that the overall beam pointing can accurately point to the target satellite.

Description

Technical Field

[0001] This application relates to the field of satellite communications, and more particularly, to an electronic beam pointing search method for a hybrid satellite communication tracking system. Background Technology

[0002] Satellite communication refers to the transmission of signals between a user terminal located on the ground and a target satellite in orbit via an electromagnetic beam. The user terminal includes fixed communication equipment or mobile communication equipment installed on a movable platform (e.g., ships and vehicles). To ensure the accuracy of the communication link, the antenna of the user terminal must precisely align its beam with the target satellite.

[0003] The user terminal's antenna transmits signals to the target satellite through beam directivity to achieve stable link transmission. When there is relative motion between the user terminal and the target satellite, the antenna needs to dynamically track the target satellite to continuously maintain beam alignment. Summary of the Invention

[0004] The main objective of this application is to provide an electronic beam pointing search method for a satellite communication hybrid tracking system. To achieve the aforementioned objective, this application employs the following technical solution: This application provides an electronic beam pointing search method for a satellite communication hybrid tracking system. When there is relative motion between the user terminal's antenna and the target satellite in orbit, the electronic beam pointing search method is executed. The electronic beam pointing search method includes pure mechanical tracking, pure electrical tracking, and hybrid tracking, wherein: Purely mechanical tracking is performed using a fixed-phase three-axis mechanism to obtain the antenna's principal axis direction. , ; Pure electrical tracking is performed by an electrical phase shifter to obtain... ; Hybrid tracking initially uses a single-step mechanical adjustment to coarsely track a larger tracking range, and then uses electrical adjustments to track a smaller tracking range. In hybrid tracking, mechanical adjustment uses the antenna's mechanical three-axis drive shaft to adjust the azimuth, elevation, and tilt angles for initial beam alignment, while electrical adjustment uses the phased array antenna's electrical phase shifter to adjust the beam pointing. The electronic beam pointing search method for the hybrid satellite communication tracking system disclosed in this application achieves accurate and responsive beam alignment when there is relative motion between the antennas of the target satellite and the user terminal by combining three-axis mechanical adjustment and electrical phase compensation mechanism. It can effectively balance system response time, mechanical wear and scanning loss while maintaining high-precision beam alignment capability, thereby improving the link stability and adaptability of the overall satellite communication system.

[0005] In some embodiments, the mechanical three-axis drive shaft controls the antenna azimuth angle, antenna downtilt angle, and antenna skew angle of the antenna to set the direction of the antenna main axis and achieve coarse beam tracking.

[0006] In some embodiments, an electrical phase shifter controls the phase of a uniform planar array of antennas to perform fine beam adjustment to correct pointing errors caused by mechanical adjustments.

[0007] In some embodiments, electrical adjustments are performed in the antenna's local coordinate system, and the incident path direction of the target satellite is obtained by calculating and converting Euler angles based on the user terminal's attitude in the geocentric coordinate system; the beam pointing is defined as... , After mechanical adjustment, coordinate system relative to Euler angles in the coordinate system, the incident path direction of the target satellite is defined as... The beam pointing is calculated based on the Euler angles and the incident path direction, i.e. .

[0008] In some embodiments, a first stage and a second stage are included. The first stage is based on a coarse tracking mechanism to acquire the main beam and control the antenna beam pointing within a 3dB beamwidth within a predefined frame header to complete pure mechanical tracking. The second stage is performed after the first stage is completed and uses coarse and fine beams to track the satellite to enhance performance. Mechanical and electrical adjustments are combined within a selected tracking area to achieve hybrid beam tracking that includes mechanical and electrical methods.

[0009] In some embodiments, electrical adjustment includes single-step electrical adjustment and multi-step electrical adjustment. Single-step electrical adjustment is for beams outside the main beam region, determining the peak position of beamforming output power based on the received signal subspace. Multi-step electrical adjustment is for gradually updating the beam pointing based on the received signal strength pointer within the main beam region.

[0010] In some embodiments, hybrid tracking includes dynamic beam alignment and static beam alignment. Dynamic beam alignment is calculated based on the orientation of the antenna relative to the body coordinate system, while static beam alignment is calculated based on ephemeris data to determine the relative position of the target satellite.

[0011] In some embodiments, the antenna's body attitude is provided by an inertial measurement unit, and the antenna's attitude angle information is obtained through rotation matrix transformation.

[0012] In some embodiments, the target satellite is located in geosynchronous orbit, and a mechanical three-axis drive shaft is used to determine the antenna skew angle.

[0013] In some embodiments, the equivalent beam pointing with dynamic phase is a function of the antenna's three-axis orientation, thereby updating the equivalent beam pointing with dynamic phase and compensating for pointing errors caused by mechanical adjustments. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in some embodiments of this application will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of this application.

[0015] Figure 1 A schematic diagram showing the three-axis deflection that a user terminal may experience during movement; Figure 2 A block diagram showing the coordinate transformation of the complete beam tracking mechanism under four key coordinate architectures; Figure 3 A schematic diagram of beam tracking for user terminals; Figure 4 A block diagram of the frame structure for beam tracking; Figure 5 This is a flowchart of beam pointing calculation. Detailed Implementation

[0016] This specification describes various embodiments, and those skilled in the art should readily understand the spirit and principles of this application by referring to the description and accompanying drawings. Here, the elements or portions depicted in the drawings may be exaggerated or varied for clarity. Therefore, those skilled in the art should understand that the dimensions and relative proportions of the elements depicted in the drawings are not the actual dimensions and relative proportions of the actual elements or portions. Furthermore, although some specific embodiments will be specifically described herein, these embodiments are merely exemplary and are not to be considered limiting or exhaustive in any way. Therefore, various changes and modifications to this application should be obvious and easily achievable by those skilled in the art without departing from the spirit and principles of this application.

[0017] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, known elements of the embodiments of this application will not be described in detail or will be omitted so as not to obscure relevant details. In the following description, specific details are set forth in the accompanying drawings and specification for purposes of explanation and not limitation in order to provide a thorough understanding of the embodiments of this application. However, it will be apparent, however, that implementation may be carried out without these specific details.

[0018] The following description, accompanied by illustrations, illustrates preferred embodiments of the present application, but is not intended to limit the scope of the application.

[0019] Figure 1 This diagram illustrates the six degrees of freedom of motion of the user terminal 10 when it is a mobile carrier located on the Earth's surface. The motion includes rotation around the X-axis (direction of travel) to form roll, rotation around the Y-axis (direction of lateral movement) to form pitch, and rotation around the Z-axis (direction of gravity) to form yaw. All of these affect the alignment of the user terminal 10's electronic beam with the target satellite in Earth orbit. Figure 1 (Not shown); The longitudinal translation (Surge) of user terminal 10 along the X-axis or the lateral translation (Sway) along the Y-axis both affect the position reference of user terminal 10 and have a minor impact on the instantaneous phase of user terminal 10. The vertical translation (Heave) of user terminal 10 along the Z-axis causes a change in the height of user terminal 10, which affects the estimation of the incident angle.

[0020] like Figures 2 to 5 As shown, the electronic beam pointing search method of the satellite communication hybrid tracking system of this application is executed when the user terminal 10 is located on the ground and there is relative motion between it and the target satellite in Earth orbit. In the satellite communication hybrid tracking system, the antenna 20 of the user terminal 10 adjusts the electronic beam pointing so that the electronic beam pointing can be aligned with the incident vector of the target satellite. .

[0021] Once antenna 20 establishes a connection with the target satellite, it can execute the electronic beam pointing search method after the initial search and initiate the beam tracking procedure for the target satellite.

[0022] Electronic beam pointing search methods include purely mechanical tracking, purely electrical tracking, and hybrid tracking that combines electromechanical methods.

[0023] Among them, pure mechanical tracking is performed by a fixed-phase three-axis mechanical shaft, which can obtain the broadside direction of horn antennas. , Its characteristics include low precision, lossless scanning at large angles, slow tracking speed, wear and tear issues, and low cost.

[0024] Pure electrical tracking, performed independently, is executed using a dynamically adjustable electrical phase shifter to obtain... Its characteristics include high precision, minimal scanning loss at large angles, fast tracking speed, no wear issues, and high cost.

[0025] Hybrid tracking is a compromise between pure mechanical tracking and pure electrical tracking achieved by using a mechanical three-axis drive shaft and an electrical phase shifter to perform tracking within a selected tracking area through a combination of mechanical and electrical adjustments.

[0026] Hybrid tracking initially performs coarse tracking of a larger (coarse) tracking range through single-step mechanical adjustments (such as program tracking), and then performs single-step electrical adjustments or multi-step electrical adjustments through program tracking for a smaller (fine) tracking range, thereby enabling fine-tuning.

[0027] Single-step mechanical adjustment and single-step electrical adjustment are programmed tracking methods based on the geographical location of the target satellite and antenna 20 and the attitude of antenna 20, respectively.

[0028] Multi-step electrical adjustment is achieved by gradually tracking based on the received signal strength indicator (RSSI) and previous tracking results. The gradual tracking method can be at least one of the following calculation methods: direct search method, gradient method, and quadratic approximation method.

[0029] The antenna pointing of user terminal 10 at the receiving end (RX) refers to the direction of antenna 20 of user terminal 10 towards the target satellite, and is defined as follows: Definition 1: Beam alignment is defined with reference to antenna 20 of user terminal 10, and its antenna coordinate system ( -frame) based on the attitude of antenna 20 (i.e., body coordinate system) The relative position of the target satellite and the antenna azimuth angle is determined by setting the antenna azimuth angle. Antenna downtilt angle Antenna skew angle This makes the plane normal of antenna 20 (i.e., the direction of the antenna's main axis) The antenna 20 is pointing towards the target satellite, and its attitude is relative to the navigation coordinate system (also known as the North-East-Down frame, NED coordinate system) in the body coordinate system. Defined by the coordinate system.

[0030] Definition 2: The antenna field pattern can be defined in a Global Coordinate System (GCS) (as shown in the references), that is, in the Earth-Centered, Earth-Fixed Frame (ECEF) coordinate system, also known as... The field shape can be transformed to any local coordinate system (LCS) through coordinate transformation (CT).

[0031] Based on the above definition, the overall beam tracking performance should be evaluated from the geocentric-ground-fixed coordinate system to the antenna coordinate system, wherein the beam tracking mechanism should take into account the geocentric-ground-fixed coordinate system. (coordinate system), and use such as Figure 2 The four key coordinate systems shown are used to effectively evaluate the performance resulting from the attitude and relative position information of antenna 20; these four key coordinate systems are the geocentric coordinate system (GCS) and the ground-fixed coordinate system (GCS). Coordinate system), navigation coordinate system Coordinate system), body coordinate system ( coordinate system) and antenna coordinate system Coordinate system).

[0032] The origin of the geocentric coordinate system is set at the Earth's center of mass. The position of antenna 20 is provided by GPS and determined through a rotation matrix. The system is transformed to the navigation coordinate system; the navigation coordinate system uses the current ground position as its origin and serves as the reference coordinate system to describe the attitude of the antenna 20; the body coordinate system defines the yaw, pitch, and roll of the user terminal 10. The attitude information can be provided by an inertial measurement unit (IMU) or other attitude sensors. The body attitude relative to the navigation coordinate system is determined by a rotation matrix. Transformation; the antenna coordinate system defines the actual pointing of antenna 20, and the antenna azimuth angle is controlled by a mechanical three-axis drive shaft. Antenna downtilt angle and antenna skew angle To set the antenna's main axis direction and achieve coarse beam tracking, the direction of antenna 20 relative to the aircraft's coordinates is determined by a rotation matrix. Conversion.

[0033] Static beam alignment is performed statically based on the orientation of antenna 20 relative to navigation coordinates, using ephemeris data, and through a rotation matrix. The coordinate transformation is completed; dynamic beam alignment is then performed by calculating the aircraft's attitude based on the orientation of antenna 20 relative to the aircraft's coordinates using real-time sensors. And by obtaining the above rotation matrix Then perform dynamic calculations: .

[0034] The performance evaluation formula is as follows: Compared to Coordinate system, by The body attitude caused by either cruise or disturbance within the coordinate system can be obtained as follows: ,in, , ,and These are the aircraft's attitude angles (roll angle, pitch angle, yaw angle). This refers to the latitude and longitude of the organism.

[0035] Beam alignment (estimation) can be obtained as follows: ,in, ,and This refers to the antenna's static beam alignment angle (skew angle, elevation angle, azimuth angle).

[0036] The beam alignment performance evaluation can be obtained as follows: .

[0037] When the antenna 20's main axis is aligned as closely as possible with the target satellite by adjusting the antenna 20's mechanical three-axis drive shaft, the target satellite's signal will follow the incident vector relative to the local coordinate system (i.e., the user terminal 10's antenna coordinate system). Enter, incident vector The incident path direction is , Indicates the azimuth angle of arrival of the incident path. The zenith angle of arrival represents the incident path, while the incident path direction of the target satellite is... It is obtained by calculating and transforming Euler angles based on the attitude of user terminal 10 in the geocentric coordinate system; and the overall channel coefficient can be defined as follows: …Formula (1).

[0038] in, Indicates the target satellite's transmission power. This represents the path fading gain from the target satellite to the antenna 20 of the user terminal 10, and , This indicates the distance between the target satellite and antenna 20. In the uniform plane array representing the target satellite and antenna 20, the first... Polarization coupling between elements is a number, and polarization coupling is a function that depends on... and ,in, This is the launch path direction angle relative to the target satellite's coordinate system to the local coordinate system.

[0039] In the local coordinate system, along The antenna spacing of antenna 20; This indicates the moving speed (including magnitude and direction) of antenna 20, where, This indicates the speed of antenna 20 relative to any of its cruise or disturbance. The direction angle of movement of the coordinate system (elevation angle and azimuth angle).

[0040] According to the aforementioned equation (1), as long as the overall beam direction obtained through mechanical and electrical adjustments is ensured... direction of incident path with the target satellite With consistent mechanical adjustment via the mechanical three-axis drive shaft, optimal performance can be easily achieved. Hybrid beam tracking mechanisms, such as Figure 3 As shown.

[0041] Key parameters The calculation is as follows: , .

[0042] After mechanical adjustment, coordinate system relative to Euler angles of coordinate system ( ); ; yes In the coordinate system, the direction of the target satellite's incident path.

[0043] against Coordinate system, direction of input of the incident beam of the target satellite yes The function, i.e. .

[0044] The hybrid tracking system employs hybrid tracking, comprising a first stage and a second stage. The first stage is the main beam acquisition stage, which acquires the main beam based on a coarse tracking mechanism at the predefined frame head. The beam pointing of antenna 20 is controlled within a 3dB beamwidth to achieve pure mechanical tracking, thus meeting the minimum link budget requirement; the frame structure for hybrid tracking is as follows: Figure 4 As shown.

[0045] The second phase is a hybrid tracking phase that enhances performance after the first phase. It utilizes both coarse and fine beams for satellite tracking to improve performance. Within a selected tracking area, it combines mechanical adjustments to the antenna 20's orientation using a mechanical three-axis drive shaft with electrical adjustments to the antenna 20's equivalent beam pointing using an electrical phase shifter. This achieves hybrid beam tracking that incorporates both mechanical and electrical methods. This further enhances tracking performance, including improving tracking accuracy, reducing tracking time, and addressing mechanical wear issues.

[0046] Hybrid tracking includes two steps executed sequentially. In step one, the antenna azimuth angle of the antenna 20 is coarsely adjusted by mechanically adjusting the antenna's three-axis drive shaft. Antenna downtilt angle Antenna skew angle In applications where the target satellite is in geostationary orbit (GEO), the antenna skew angle... This step alone can determine the outcome, and step one cannot provide additional degrees of freedom (DoF) on the x-axis of the mechanical triaxial drive shaft.

[0047] Step two, performed after step one, involves electrically adjusting the phase of the uniform planar array of the phased array antenna by controlling the phase shifter of the phased array antenna. This electrical adjustment is performed in the local coordinate system of antenna 20 to finely adjust the beam pointing and align it with the incident path direction of the target satellite. Angle of arrival (AOA) and zenith-of-arrival (ZOA) This is to correct the pointing error caused by mechanical adjustments.

[0048] Two-dimensional electrical phase shifters provide in - Additional degrees of freedom in the plane, to further improve the beam pointing azimuth angle of arrival of antenna 20. and zenith reach angle The accuracy.

[0049] During the mechanical adjustment of hybrid tracking, the three-axis angle of antenna 20 After setting via the mechanical three-axis drive shaft of antenna 20, an equivalent beam pointing with a fixed phase can be obtained. , Pointing error caused by mechanical adjustment Defined as .in, It is the incident direction of the target satellite relative to the main axis of the antenna, and it is The function, that is The azimuth angle of antenna 20 is adjusted via a mechanical three-axis drive shaft. Antenna downtilt angle Antenna skew angle It can obtain an equivalent beam pointing with a fixed phase. This allows the main axis of antenna 20 to be aligned with the target satellite as much as possible.

[0050] Beam pointing electrical adjustment obtains an equivalent beam pointing with dynamic phase through an electrical phase shifter. The equivalent beam pointing with dynamic phase It is based on the antenna main axis direction obtained by mechanical adjustment of antenna 20 and the incident path direction of the target satellite relative to the antenna main axis direction. Dynamically updated, with dynamic phase equivalent beam pointing It is a function of the three axes of the antenna, that is... This results in an equivalent beam pointing with dynamic phase. Updated and equivalent to mechanical adjustment of pointing error Then the overall beam direction Ideally, it can be pointed in the direction of the incident path of the target satellite. To achieve ideal beam alignment.

[0051] therefore, .

[0052] final, .

[0053] In summary, regarding hybrid tracking and mechanical adjustments, the antenna orientation based on a three-axis (azimuth, elevation, and tilt) mechanical rotation can be expressed as follows: The beam propagation direction of the target satellite relative to the antenna's main axis (20) will be a function of the antenna's direction along the mechanical rotating axis. At this point, the corresponding equivalent beam pointing with a fixed phase can be fixed as follows: Therefore, the pointing error can be expressed as: Regarding electrical adjustment, when the antenna 20 has a dynamically adjustable electrical phase shifter, the equivalent beam pointing with dynamic phase is... If the overall beam direction after mechanical adjustment is In order to achieve the adjustment goals The solution for dynamic phase adjustment would then be... .

[0054] like Figure 5 As shown, the beam points It is based on Euler angles and the direction of the incident path Calculated beam pointing The calculation is as follows: .

[0055] Mechanisms for achieving fine beam tracking through electrical adjustments include single-step electrical adjustments and multi-step electrical adjustments. Single-step electrical adjustments are a type of beam tracking for beams outside the main beam area. The peak location (PL) of the beamforming output power is determined based on the received signal subspace. The peak location can also be calculated by programmable control as a coarse tracking method.

[0056] Multi-step electrical adjustment is beam tracking within the main beam area (e.g., within a 3dB beamwidth), with the peak position calculated step-by-step based on the received signal strength pointer.

[0057] The current antenna attitude is determined by the three-axis angles caused by the mechanical three-axis drive shaft. The reference antenna direction corresponding to the principal axis direction is represented as follows: It is equal to the previous antenna orientation. The orientation error caused by mechanical adjustment is expressed as: .

[0058] Half of the field-of-view (FoV) of fine beam tracking is defined as... For a target satellite in geostationary orbit, the antenna skew angle Updates are performed only through mechanical adjustments; for target satellites not in geostationary orbit, there is no need to update the antenna skew angle. Furthermore, half 3dB beamwidth is defined as .

[0059] Based on the tracking range, the tracking modes can be divided into the first tracking mode, the second tracking mode, and the third tracking mode. The first tracking mode corresponds to the first tracking area, the second tracking mode corresponds to the second tracking range, and the third tracking mode corresponds to the third tracking range. Furthermore, the first tracking area is larger than the second tracking area, and the second tracking area is larger than the third tracking area. In other words, the first tracking mode corresponds to a larger tracking area, covering a wide range of incident directions; the second tracking mode corresponds to a medium tracking range, balancing speed and accuracy; and the third tracking mode corresponds to a smaller tracking range, requiring high-frequency updates and high computational load for fine beam alignment.

[0060] The electronic beam pointing search method for a hybrid satellite communication tracking system disclosed in this application achieves accurate and responsive beam alignment when there is relative motion between the target satellite and antenna 20 by combining three-axis mechanical adjustment and electrical phase compensation mechanisms. The method offers the following technical advantages: First, it enables rapid search and coarse beam guidance of the target satellite direction, reducing the initial beam acquisition time. Second, it allows for further fine-tuning through electrical phase control to improve beam pointing estimation accuracy and reduce pointing errors. Third, it allows for dynamic switching of tracking modes (e.g., a low-frequency updated wide-area search mode and a high-frequency updated fine-tuning mode) based on communication link quality indicators, balancing system response speed and computational load. Fourth, it reduces the need for frequent tracking adjustments relying on mechanical components, thereby reducing structural wear and improving system stability. Fifth, it can be applied to various platform types of terminal equipment, including fixed or mobile ground stations, vehicle-mounted or shipborne communication systems, or airborne platforms, demonstrating good feasibility and application flexibility.

[0061] Compared to existing technologies that use only a single mechanical or electrical tracking method, this application can effectively balance system response time and resource consumption while maintaining high-precision beam alignment capabilities, thereby improving the link stability and adaptability of the overall satellite communication system.

[0062] The above description is merely some preferred embodiments of this application. It should be noted that various changes and modifications can be made to this application without departing from the spirit and principles of this application. Those skilled in the art should understand that this application is defined by the appended claims, and that various possible substitutions, combinations, modifications, and transformations, etc., do not exceed the scope defined by the appended claims, provided they conform to the meaning of this application.

Claims

1. An electronic beam pointing search method for a satellite communication hybrid tracking system, wherein when there is relative motion between a user terminal located on the ground and a target satellite in Earth orbit, the electronic beam pointing search method establishes a connection between the antenna of the user terminal and the target satellite, and the antenna is executed after the initial search; The electronic beam pointing search method is characterized in that... It includes pure mechanical tracking, pure electronic tracking, and hybrid tracking. Hybrid tracking involves performing electrical adjustments after mechanical adjustments within a selected tracking area to obtain an equivalent beam pointing with dynamic phase. The equivalent beam pointing with dynamic phase is dynamically updated based on the antenna main axis direction obtained through the mechanical adjustments and the incident path direction of the target satellite relative to the antenna main axis direction, so that the overall beam pointing is ideally directed toward the incident path of the target satellite. The mechanical adjustment is performed by the antenna's mechanical three-axis drive shaft, and the electrical adjustment is performed by the antenna's electrical phase shifter.

2. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The mechanical three-axis drive shaft controls the antenna azimuth angle, antenna downtilt angle, and antenna skew angle to set the antenna main axis direction and achieve coarse beam tracking.

3. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The electrical phase shifter controls the phase of the uniform planar array of the antenna to perform fine beam adjustment in order to correct pointing errors caused by mechanical adjustments.

4. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The electrical adjustments are performed in the antenna's local coordinate system, and the incident path direction of the target satellite is obtained by calculating and converting Euler angles based on the user terminal's attitude in the geocentric coordinate system. Beam pointing is defined as , After mechanical adjustment, coordinate system relative to Euler angles in the coordinate system, the incident path direction of the target satellite is defined as... The beam pointing is calculated based on the Euler angles and the incident path direction, i.e. .

5. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, It includes a first stage and a second stage; the first stage is based on the coarse tracking mechanism to acquire the main beam, and controls the antenna beam pointing within a 3dB beamwidth within a predefined frame header to complete pure mechanical tracking; The second phase is performed after the first phase is completed, using coarse and fine beams for satellite tracking to enhance performance, and combining the mechanical and electrical adjustments within a selected tracking area to achieve hybrid beam tracking that incorporates both mechanical and electrical methods.

6. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The electrical adjustment includes single-step electrical adjustment and multi-step electrical adjustment. The single-step electrical adjustment is for the beam outside the main beam area, and determines the peak position of the beamforming output power based on the received signal subspace. The multi-step electrical adjustment is to gradually update the beam pointing based on the received signal strength pointer within the main beam area.

7. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The hybrid tracking includes dynamic beam alignment and static beam alignment; the dynamic beam alignment is calculated based on the direction of the antenna relative to the body coordinate system; the static beam alignment is calculated based on ephemeris data to determine the relative position of the target satellite.

8. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The antenna's body attitude is provided by the inertial measurement unit, and the antenna's attitude angle information is obtained through rotation matrix transformation.

9. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The target satellite is located in geosynchronous orbit, and the mechanical three-axis drive shaft is used to determine the antenna deflection angle.

10. The electronic beam pointing search method for a satellite communication hybrid tracking system according to claim 1, characterized in that, The equivalent beam pointing with dynamic phase is a function of the antenna's three-axis direction, thereby updating the equivalent beam pointing with dynamic phase and compensating for the pointing error of the mechanical adjustment.

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