A high-precision initial pointing method and system for ground-based fixed-point laser communication terminals

Abstract

The present invention relates to the field of laser communication technology, and more specifically to a high-precision initial pointing method and system for a ground-based fixed-point laser communication terminal. The method comprises: installing a ground turntable and obtaining a measured azimuth of a GNSS baseline; obtaining the acquisition azimuth and acquisition pitch angle of a target star at each moment; iteratively adjusting the azimuth and pitch angles based on the measured azimuth of the GNSS baseline and the acquisition azimuth and acquisition pitch angle of the target star at each moment until an optimal theoretical azimuth and optimal theoretical pitch angle are obtained; and adjusting the optimal theoretical azimuth and optimal theoretical pitch angle as optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal. The present invention improves the accuracy of the initial pointing of the laser communication terminal by adjusting the azimuth and pitch angles.

Description

Technical Field

[0001] The present invention relates to the field of laser communication technology, and in particular to a high-precision initial pointing method and system for a ground-based fixed-point laser communication terminal. Background Art

[0002] The construction and application of a new generation of ground information network systems directly determines the effectiveness of comprehensive support systems such as post-disaster reconstruction and ground exploration. Therefore, the establishment of a high-capacity, highly concealed ground-based three-dimensional spatial local information network is urgently needed. Ground-based three-dimensional spatial local information networks based on optical information networks can meet the needs of rapid deployment and emergency communications. Furthermore, three-dimensional spatial local information networks based on laser communication offer significant advantages in terms of large information capacity and high security, providing strong support for ground-based local information communications.

[0003] The optical information age demands the establishment of communication network systems with high transmission rates, large information volumes, and wide spatial coverage. Space laser communications, utilizing extremely short wavelength light waves, are the optimal solution for achieving high data rate communications. Space laser communications are favored for their high transmission capacity, compact size, and low power consumption. However, these advantages rely on the high transmit and receive gain provided by a small divergence angle beam, which places higher demands on the speed and stability of beam acquisition and tracking than microwave communications.

[0004] The divergence angle of tens of microradians makes it difficult to quickly achieve two-way capture. In the early stages of laser communication terminals entering orbit, it usually takes dozens of days to perform on-orbit calibration of pointing accuracy, which hinders the user's application needs for rapid launch and rapid deployment. In space-based local information networks, limitations such as calibration accuracy, space platform attitude drift, and micro-vibration will seriously restrict the time it takes to establish and deploy laser communication links. In addition, due to the small laser beam, high alignment accuracy requirements, and mechanical and structural micro-deformations, changes in the mechanical and thermal environment, etc., which will affect long-term communication stability, there are currently few public reports on the long-term working stability of lasers at home and abroad, and most reports are limited to the realization of demonstration and verification functions. Summary of the Invention

[0005] The present invention provides a high-precision initial pointing method and system for a ground-based fixed-point laser communication terminal, which solves the problems of insufficient initial pointing accuracy, slow deployment speed and poor long-term stability in existing laser communication technologies.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The first aspect of the present invention is to provide a high-precision initial pointing method for a ground-based fixed-point laser communication terminal, comprising:

[0008] Get the measured azimuth of the GNSS baseline;

[0009] Obtain the acquisition azimuth and acquisition pitch angle of the target star at each moment;

[0010] According to the measured azimuth of the GNSS baseline, the collected azimuth and pitch angle of the target star at each moment, iterative adjustments are made until the optimal theoretical azimuth and pitch angle are obtained. The optimal theoretical azimuth and pitch angle are used as the optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal.

[0011] Furthermore, obtaining the measured azimuth of the GNSS baseline includes:

[0012] The angle between the GNSS dual-antenna baseline direction and the true north direction is taken as the azimuth measurement value of the GNSS baseline and recorded as the measured azimuth of the GNSS baseline.

[0013] Furthermore, obtaining the acquisition azimuth and pitch angle of the target star at each moment includes:

[0014] The azimuth and pitch angles of the target star at each moment are obtained through STK software, and are recorded as the acquisition azimuth and acquisition pitch angles of the target star at each moment, respectively.

[0015] Furthermore, the iterative adjustment is performed according to the measured azimuth of the GNSS baseline, the collected azimuth and the collected elevation angle of the target star at each moment until the optimal theoretical azimuth and the optimal theoretical elevation angle are obtained, including:

[0016] Step 1: Obtain the theoretical azimuth and theoretical pitch angle at each moment based on the measured azimuth of the GNSS baseline and the collected azimuth and pitch angle of the target star at each moment; determine whether there is a target star within the field of view of the ground turntable corresponding to the theoretical azimuth and theoretical pitch angle at each moment. If there is no target star, jump to step 2; if there is a target star, adjust to step 5;

[0017] Step 2: Manually adjust the turntable so that the target star appears in the center of the turntable's field of view. At this time, record the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable's field of view; calculate the azimuth error value and pitch angle error value corresponding to each moment based on the theoretical azimuth and theoretical pitch angle, the actual azimuth and actual pitch angle at each moment, and determine whether the azimuth error value and the pitch angle error value are both within the preset error range. If not, jump to step 3; if within the preset error range, jump to step 4;

[0018] Step 3: Calculate the azimuth correction value and pitch angle correction value corresponding to each moment based on the azimuth correction value and pitch angle correction value corresponding to the previous moment and the azimuth error value and pitch angle error value corresponding to each moment, obtain the acquisition azimuth and acquisition pitch angle of the target star at the next moment, and jump to step 1;

[0019] Step 4: Output the actual azimuth angle and the actual pitch angle as the optimal theoretical azimuth angle and the optimal theoretical pitch angle, and jump to step 6;

[0020] Step 5: Output the theoretical azimuth angle and theoretical pitch angle at each moment as the optimal theoretical azimuth angle and optimal theoretical pitch angle, and jump to step 6;

[0021] Step 6: Determine the high-precision initial pointing direction of the laser communication terminal based on the optimal theoretical azimuth angle and the optimal theoretical elevation angle.

[0022] Furthermore, obtaining the theoretical azimuth and theoretical pitch angle at each moment based on the measured azimuth of the GNSS baseline and the collected azimuth and pitch angle of the target star at each moment includes:

[0023]

[0024]

[0025] Where, Indicates the acquisition azimuth of the target star at each moment, Indicates the azimuth correction value corresponding to the previous moment, Indicates the measured azimuth of the GNSS baseline, Indicates the theoretical azimuth of the target star at each moment; Indicates the acquisition pitch angle of the target star at each moment, Indicates the pitch angle correction value corresponding to the previous moment, Indicates the theoretical pitch angle of the target star at each moment.

[0026] Furthermore, the calculation of the azimuth error value and the pitch angle error value corresponding to each moment according to the theoretical azimuth angle and the theoretical pitch angle, the actual azimuth angle and the actual pitch angle at each moment includes:

[0027] The difference between the theoretical azimuth angle at each moment and the corresponding actual azimuth angle is recorded as the azimuth angle error value corresponding to each moment; the difference between the theoretical pitch angle at each moment and the corresponding actual pitch angle is recorded as the pitch angle error value corresponding to each moment.

[0028] Furthermore, the step of calculating the azimuth correction value and the pitch angle correction value corresponding to each moment based on the azimuth correction value and the pitch angle correction value corresponding to the previous moment and the azimuth error value and the pitch angle error value corresponding to each moment includes:

[0029] The difference between the azimuth correction value corresponding to the previous moment and the azimuth error value corresponding to each moment is used as the azimuth correction value corresponding to each moment; the difference between the pitch angle correction value corresponding to the previous moment and the pitch angle error value corresponding to each moment is used as the pitch angle correction value corresponding to each moment.

[0030] The second aspect of the present invention is to provide a high-precision initial pointing system for a ground-based fixed-point laser communication terminal, comprising:

[0031] The measurement module is used to obtain the measurement azimuth of the GNSS baseline;

[0032] Theoretical calculation module, used to obtain the acquisition azimuth and pitch angle of the target star at each moment;

[0033] The error correction module is used to perform iterative adjustments based on the measured azimuth of the GNSS baseline, the acquisition azimuth and acquisition pitch angle of the target star at each moment, until the optimal theoretical azimuth and optimal theoretical pitch angle are obtained; the optimal theoretical azimuth and optimal theoretical pitch angle are used as the optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal.

[0034] The third aspect of the present invention is to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein when the processor executes the computer program, it implements the high-precision initial pointing method of a ground-based fixed-point laser communication terminal.

[0035] The fourth aspect of the present invention is to provide a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the high-precision initial pointing method of a ground-based fixed-point laser communication terminal.

[0036] Compared with the prior art, the beneficial effects of the present invention are: obtaining the measured azimuth of the GNSS baseline, reducing the problems of insufficient geographic reference accuracy and poor deployment flexibility; obtaining the acquisition azimuth and acquisition pitch angles of the target star at each moment; improving the accuracy of the deviation analysis caused by the deformation or vibration of the detection turntable; performing iterative adjustments based on the measured azimuth of the GNSS baseline, the acquisition azimuth and acquisition pitch angles of the target star at each moment, until the optimal theoretical azimuth and the optimal theoretical pitch angle are obtained, reducing the deployment time and increasing the deployment speed through iteration, and improving the accuracy of the parameters in the iterative process of obtaining the optimal parameters, thereby reducing the instability factors caused by equipment errors or environmental changes, thereby improving long-term stability; adjusting the optimal theoretical azimuth and the optimal theoretical pitch angle as the optimal parameters for adjusting the turntable to complete the high-precision initial pointing determination of the laser communication terminal, reducing the lack of long-term pointing stability, and improving the accuracy of the initial pointing of the laser communication terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 The present invention provides a schematic flow chart of the steps of a high-precision initial pointing method for a ground-based fixed-point laser communication terminal;

[0039] Figure 2 The present invention provides a module flow diagram of a high-precision initial pointing system for a ground-based fixed-point laser communication terminal;

[0040] Figure 3 This is a schematic diagram of the installation and connection of the GNSS dual antenna and the laser communication terminal;

[0041] Figure 4 Determine the flow chart for high-precision initial pointing. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] In response to the problems existing in the background technology, a high-precision initial pointing method and system for ground-based fixed-point laser communication terminals were studied and designed, which has important practical significance.

[0045] like Figure 1 As shown, the first aspect of the present invention is to provide a high-precision initial pointing method for a ground-based fixed-point laser communication terminal, comprising the following steps:

[0046] Step S001: Installing a ground turntable and obtaining the measurement azimuth of the GNSS baseline.

[0047] It should be noted that GNSS (Global Navigation Satellite System) baseline measurements can accurately determine the relative position of a ground turntable relative to a known reference point. By performing a baseline measurement between two receivers (receiving ends), the exact relative position and distance between them can be determined, providing precise reference data for calculating azimuth and pitch angles. GNSS baseline measurements also support real-time dynamic monitoring, which is crucial for adjusting the azimuth and pitch angles of a ground turntable. GNSS baseline measurements enable real-time monitoring of changes in the ground turntable relative to the reference point, compensating for errors caused by changes in the ground platform or turntable position (such as minor vibrations and equipment drift), enabling rapid angle adjustments. Using the data obtained from baseline measurements, the system can correct the turntable's attitude in real time to ensure accurate azimuth and pitch angles.

[0048] It should be further explained that in order to ensure that the ground turntable has no impact on the GNSS baseline measurement, certain installation rules need to be followed when installing the ground turntable to ensure the levelness and stability of the installation.

[0049] Specifically, the ground turntable is installed horizontally at the experimental site. When installing the ground turntable, ensure that the azimuth zero position of the turntable is installed perpendicular to the GNSS dual-antenna baseline. The angle between the GNSS dual-antenna baseline direction and the true north direction is used as the azimuth measurement value of the GNSS baseline, which is recorded as the measured azimuth of the GNSS baseline.

[0050] The installation and connection diagram of the GNSS dual antenna and the laser communication terminal is as follows: Figure 3 As shown; the installation connection between the GNSS dual antenna and the laser communication terminal includes a first GNSS receiving end 1, a second GNSS receiving end 2, a dual-station GNSS mounting rod 3, a laser communication terminal 4 and a mounting substrate 5; the first GNSS receiving end 1 and the second GNSS receiving end 2 are respectively connected to the dual-station GNSS mounting rod 3, the dual-station GNSS mounting rod 3 is connected to the mounting substrate 5, and the laser communication terminal 4 is fixedly mounted on the mounting substrate 5.

[0051] The GNSS dual-antenna baseline and the dual-station GNSS mounting pole 3 have the same direction.

[0052] At this point, the measured azimuth of the GNSS baseline is obtained.

[0053] Step S002: Obtain the acquisition azimuth and acquisition pitch angle of the target star at each moment through STK software.

[0054] It should be noted that since the measured azimuth of the GNSS baseline has fully taken into account actual measurement errors and environmental factors, it can serve as a reference standard and can therefore help correct other azimuth and elevation angles derived from theoretical calculations.

[0055] Specifically, the azimuth and elevation angles of the target star at each moment are obtained using STK software, and are recorded as the acquisition azimuth and acquisition elevation angles of the target star at each moment, respectively. In this embodiment, the target star is star 113368, and 113368 is the HD (Henry Draper Catalogue) number of the target star.

[0056] At this point, the acquisition azimuth and acquisition pitch angle of the target star at each moment are obtained.

[0057] Step S003: Adjust the ground turntable according to the acquisition azimuth and acquisition pitch angle of the target star at each moment, rotate the turntable to the target position, and then judge the situation of the target star in the field of view of the ground turntable to make subsequent adjustments to the ground turntable until the turntable reaches the optimal position.

[0058] The specific process of determining the initial pointing accuracy of the laser communication terminal in the first step is as follows:

[0059] Step 1: Obtain the theoretical azimuth and theoretical pitch angle at each moment based on the measured azimuth of the GNSS baseline and the collected azimuth and pitch angle of the target star at each moment; determine whether there is a target star within the field of view of the ground turntable corresponding to the theoretical azimuth and theoretical pitch angle at each moment. If there is no target star, jump to step 2; if there is a target star, adjust to step 5;

[0060] Step 2: Manually adjust the turntable so that the target star appears in the center of the turntable's field of view. At this time, record the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable's field of view; calculate the azimuth error value and pitch angle error value corresponding to each moment based on the theoretical azimuth and theoretical pitch angle, the actual azimuth and actual pitch angle at each moment, and determine whether the azimuth error value and the pitch angle error value are both within the preset error range. If not, jump to step 3; if within the preset error range, jump to step 4;

[0061] Step 3: Calculate the azimuth correction value and pitch angle correction value corresponding to each moment based on the azimuth correction value and pitch angle correction value corresponding to the previous moment and the azimuth error value and pitch angle error value corresponding to each moment, obtain the acquisition azimuth and acquisition pitch angle of the target star at the next moment, and jump to step 1;

[0062] Step 4: Output the actual azimuth angle and the actual pitch angle as the optimal theoretical azimuth angle and the optimal theoretical pitch angle, and jump to step 6;

[0063] Step 5: Output the theoretical azimuth angle and theoretical pitch angle at each moment as the optimal theoretical azimuth angle and optimal theoretical pitch angle, and jump to step 6;

[0064] Step 6: Determine the high-precision initial pointing direction of the laser communication terminal based on the optimal theoretical azimuth angle and the optimal theoretical elevation angle.

[0065] Among them, the theoretical azimuth angle and theoretical pitch angle at each moment are specifically expressed by the formula:

[0066]

[0067]

[0068] Where, Indicates the acquisition azimuth of the target star at each moment, Indicates the azimuth correction value corresponding to the previous moment, Indicates the measured azimuth of the GNSS baseline, Indicates the theoretical azimuth of the target star at each moment; Indicates the acquisition pitch angle of the target star at each moment, Indicates the pitch angle correction value corresponding to the previous moment, Indicates the theoretical pitch angle of the target star at each moment.

[0069] The difference between the theoretical azimuth and the corresponding actual azimuth at each moment is recorded as the azimuth error value corresponding to each moment; the difference between the theoretical pitch angle and the corresponding actual pitch angle at each moment is recorded as the pitch error value corresponding to each moment. The difference between the azimuth correction value corresponding to the previous moment and the azimuth error value corresponding to each moment is recorded as the azimuth correction value corresponding to each moment; the difference between the pitch correction value corresponding to the previous moment and the pitch error value corresponding to each moment is recorded as the pitch correction value corresponding to each moment.

[0070] The specific process of determining the initial pointing accuracy of the laser communication terminal described in detail in the second method is as follows:

[0071] Obtained through the STK (Systems Tool Kit) software The azimuth and elevation angles of the target star at the moment are recorded as the first acquisition azimuth and the first acquisition elevation angle; according to the first acquisition azimuth and the first acquisition elevation angle, the measured azimuth of the GNSS baseline, the initial azimuth correction value and the initial elevation correction value, we can obtain The theoretical azimuth and theoretical pitch angle of the target star at the moment are recorded as the first theoretical azimuth and the first theoretical pitch angle; the turntable is rotated to the first target position corresponding to the first theoretical azimuth and the first theoretical pitch angle, and then it is observed whether there is a target star in the turntable field of view at the first target position. When the target star is in the turntable field of view, the turntable is no longer adjusted, and the first theoretical azimuth and the first theoretical pitch angle are used as the optimal theoretical azimuth and the optimal theoretical pitch angle; when the target star does not exist in the turntable field of view, the turntable is manually adjusted so that the target star appears in the center of the turntable field of view; at this time, the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable field of view are recorded, and recorded as the first actual azimuth and the first actual pitch angle;

[0072] Calculate the difference between the first theoretical azimuth and the first actual azimuth, record it as a first azimuth error value, and record the result of subtracting the first azimuth error value from zero as a first azimuth correction value; calculate the difference between the first theoretical pitch angle and the first actual pitch angle, record it as a first pitch error value, and record the result of subtracting the first pitch error value from zero as a first pitch correction value; determine whether the first azimuth error value and the first pitch error value are both within a preset error range; if they are within the preset error range, use the first actual azimuth and the first actual pitch angle as the optimal theoretical azimuth and the optimal theoretical pitch angle; if they are not within the preset error range, continue with subsequent determination;

[0073] Obtained through STK software The azimuth and elevation angles of the target star at the moment are recorded as the second acquisition azimuth and the second acquisition elevation angle; according to the second acquisition azimuth and the second acquisition elevation angle, the measured azimuth of the GNSS baseline, the first azimuth correction value and the first elevation correction value, the The theoretical azimuth and theoretical pitch angles of the target star at the moment are recorded as the second theoretical azimuth and the second theoretical pitch angle; the turntable is rotated to the second target position corresponding to the second theoretical azimuth and the second theoretical pitch angle, and then it is observed whether there is a target star in the turntable field of view at the second target position. When the target star is in the turntable field of view, the turntable is no longer adjusted, and the second theoretical azimuth and the second theoretical pitch angle are used as the optimal theoretical azimuth and the optimal theoretical pitch angle; when the target star is not in the turntable field of view, the turntable is manually adjusted so that the target star appears in the center of the turntable field of view; at this time, the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable field of view are recorded, and recorded as the second actual azimuth and the second actual pitch angle;

[0074] Calculating a difference between the second theoretical azimuth and the second actual azimuth, and recording it as a second azimuth error value; recording the difference between the first azimuth correction value and the second azimuth error value as a second azimuth correction value; calculating a difference between the second theoretical pitch angle and the second actual pitch angle, and recording it as a second pitch error value; and recording the difference between the first pitch correction value and the second pitch error value as a second azimuth correction value; determining whether the second azimuth error value and the second pitch error value are both within a preset error range; and if so, using the second actual azimuth and the second actual pitch angle as the optimal theoretical azimuth and the optimal theoretical pitch angle; and if not, continuing with subsequent determinations;

[0075] Obtained through STK software The azimuth and elevation angles of the target star at the moment are recorded as the third acquisition azimuth and the third acquisition elevation angle; according to the third acquisition azimuth and the third acquisition elevation angle, the measured azimuth of the GNSS baseline, the second azimuth correction value and the second elevation correction value, the The theoretical azimuth and theoretical pitch angle of the target star at the moment are recorded as the third theoretical azimuth and the third theoretical pitch angle; the turntable is rotated to a third target position corresponding to the third theoretical azimuth and the third theoretical pitch angle, and then it is observed whether there is a target star in the turntable field of view at the third target position. When the target star is in the turntable field of view, the turntable is no longer adjusted, and the third theoretical azimuth and the third theoretical pitch angle are used as the optimal theoretical azimuth and the optimal theoretical pitch angle; when the target star does not exist in the turntable field of view, the turntable is manually adjusted so that the target star appears in the center of the turntable field of view; at this time, the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable field of view are recorded, and recorded as the third actual azimuth and the third actual pitch angle;

[0076] Calculate the difference between the third theoretical azimuth and the third actual azimuth, and record it as the third azimuth error value; record the difference between the second azimuth correction value and the third azimuth error value as the third azimuth correction value; calculate the difference between the third theoretical pitch angle and the third actual pitch angle, and record it as the third pitch angle error value; record the difference between the second pitch angle correction value and the third pitch angle error value as the third pitch angle correction value; determine whether the third azimuth error value and the third pitch angle error value are both within a preset error range; if they are within the preset error range, use the third actual azimuth and the third actual pitch angle as the optimal theoretical azimuth and the optimal theoretical pitch angle; if they are not within the preset error range, continue with subsequent determination;

[0077] Then, the calculation of subsequent theoretical azimuth and theoretical pitch angles is continued using the third azimuth correction value and the third pitch angle correction value until a condition is reached where the turntable no longer needs to be adjusted and the iteration is stopped; the theoretical azimuth and theoretical pitch angle corresponding to the adjustment stop are recorded as the optimal theoretical azimuth and optimal theoretical pitch angle. In this embodiment, the preset error range is In this embodiment, the preset error range is not specifically limited and can be determined by the implementer according to the specific situation.

[0078] It should be noted that time, Time and The moments are determined in chronological order according to the adjustment of the turntable; time, Time and There is no equal relationship between the time intervals between adjacent moments in the moment. Moment represents the first moment, Moment represents the second moment, The time represents the third time. In this embodiment, the initial azimuth correction value and the initial pitch angle correction value are respectively recorded as 0.

[0079] The process of obtaining the first theoretical azimuth angle and the first theoretical elevation angle is expressed as follows:

[0080]

[0081]

[0082] Where, Indicates the acquisition azimuth of the target star at the first moment, represents the initial azimuth correction value, represents the theoretical azimuth of the target star at the first moment; Indicates the acquisition pitch angle of the target star at the first moment, Indicates the initial pitch angle correction value, Indicates the theoretical pitch angle of the target star at the first moment.

[0083] The process of obtaining the second theoretical azimuth angle and the second theoretical elevation angle is expressed as follows:

[0084]

[0085]

[0086] Where, Indicates the acquisition azimuth of the target star at the second moment, Indicates the first azimuth correction value, represents the theoretical azimuth of the target star at the second moment; Indicates the acquisition pitch angle of the target star at the second moment, Indicates the first pitch angle correction value, Indicates the theoretical pitch angle of the target star at the second moment.

[0087] The process of obtaining the third theoretical azimuth angle and the third theoretical elevation angle is expressed as follows:

[0088]

[0089]

[0090] Where, Indicates the acquisition azimuth of the target star at the third moment, Indicates the second azimuth correction value, represents the theoretical azimuth of the target star at the third moment; Indicates the acquisition pitch angle of the target star at the third moment, Indicates the second pitch angle correction value, Indicates the theoretical pitch angle of the target star at the third moment.

[0091] The optimal theoretical azimuth angle and the optimal theoretical pitch angle are adjusted as the optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal.

[0092] The simulation data process implemented is as follows:

[0093] First, determine the measurement azimuth of the GNSS baseline as ;

[0094] Then, the first acquisition azimuth of the target star 113368 at 19:14:00 on November 4, 2023 is obtained through STK software. and the first acquisition pitch angle , the first theoretical azimuth angle obtained by calculation is , the first theoretical pitch angle is ; The first actual azimuth after adjustment and the first actual pitch angle , the calculated first azimuth error value and the first pitch angle error value , the first azimuth correction value and the first pitch angle correction value ;

[0095] The second acquisition azimuth of the target star 113368 at 19:28:39 on November 4, 2023 is obtained using STK software. and the second acquisition pitch angle , the second theoretical azimuth angle obtained by calculation is , the second theoretical pitch angle is ; The second actual azimuth after adjustment and the second actual pitch angle , the calculated second azimuth error value and the second pitch angle error value , the second azimuth correction value and the second pitch angle correction value ;

[0096] The third acquisition azimuth of the target star 113368 at 20:58:23 on November 4, 2023 is obtained using STK software. and the third acquisition pitch angle , the third theoretical azimuth angle obtained by calculation is , the third theoretical pitch angle is ; The third actual azimuth after adjustment and the third actual pitch angle , the calculated third-party azimuth error value and the third pitch angle error value , third-party azimuth correction value and the third pitch angle correction value .

[0097] Among them, the high-precision initial pointing determination flow chart is as follows Figure 4 shown.

[0098] like Figure 2 As shown, the second aspect of the present invention is to provide a high-precision initial pointing system for a ground-based fixed-point laser communication terminal, comprising the following modules:

[0099] The measurement module 101 is used to obtain the measurement azimuth of the GNSS baseline;

[0100] Theoretical calculation module 102 is used to obtain the acquisition azimuth and acquisition pitch angle of the target star at each moment;

[0101] The error correction module 103 is used to perform iterative adjustments based on the measured azimuth of the GNSS baseline, the acquisition azimuth and acquisition pitch angle of the target star at each moment, until the optimal theoretical azimuth and the optimal theoretical pitch angle are obtained; the optimal theoretical azimuth and the optimal theoretical pitch angle are adjusted as the optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal.

[0102] The third aspect of the present invention is to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the computer program, a high-precision initial pointing method for a ground-based fixed-point laser communication terminal is implemented.

[0103] The fourth aspect of the present invention is to provide a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, a high-precision initial pointing method for a ground-based fixed-point laser communication terminal is implemented.

[0104] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, optical storage, etc.) containing computer-usable program code.

[0105] The present invention is described with reference to flowcharts and / or block diagrams of methods, systems, and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0106] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0107] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the present invention.

Claims

1. A high-precision initial pointing method for a ground-based fixed-point laser communication terminal, characterized in that: include: Obtaining a measured azimuth of the GNSS baseline, including taking the angle between the GNSS dual-antenna baseline direction and the true north direction as a measured azimuth value of the GNSS baseline, recorded as the measured azimuth of the GNSS baseline; Obtain the acquisition azimuth and acquisition pitch angle of the target star at each moment; According to the measured azimuth of the GNSS baseline, the acquisition azimuth and acquisition pitch angle of the target star at each moment, iterative adjustments are made until the optimal theoretical azimuth and optimal theoretical pitch angle are obtained, including: Step 1: Obtain the theoretical azimuth and theoretical pitch angle at each moment based on the measured azimuth of the GNSS baseline and the collected azimuth and pitch angle of the target star at each moment; determine whether there is a target star within the field of view of the ground turntable corresponding to the theoretical azimuth and theoretical pitch angle at each moment. If there is no target star, jump to step 2; if there is a target star, adjust to step 5; Step 2: Manually adjust the turntable so that the target star appears in the center of the turntable's field of view. At this time, record the actual azimuth and actual pitch angle of the turntable when the target star is in the center of the turntable's field of view; calculate the azimuth error value and pitch angle error value corresponding to each moment based on the theoretical azimuth and theoretical pitch angle, the actual azimuth and actual pitch angle at each moment, and determine whether the azimuth error value and the pitch angle error value are both within the preset error range. If not, jump to step 3; if within the preset error range, jump to step 4; Step 3: Calculate the azimuth correction value and pitch angle correction value corresponding to each moment based on the azimuth correction value and pitch angle correction value corresponding to the previous moment and the azimuth error value and pitch angle error value corresponding to each moment, obtain the acquisition azimuth and acquisition pitch angle of the target star at the next moment, and jump to step 1; Step 4: Output the actual azimuth angle and the actual pitch angle as the optimal theoretical azimuth angle and the optimal theoretical pitch angle, and jump to step 6; Step 5: Output the theoretical azimuth angle and theoretical pitch angle at each moment as the optimal theoretical azimuth angle and optimal theoretical pitch angle, and jump to step 6; Step 6: Determine the high-precision initial pointing direction of the laser communication terminal according to the optimal theoretical azimuth angle and the optimal theoretical elevation angle; The obtaining of the theoretical azimuth angle and the theoretical pitch angle at each moment includes: Where, Indicates the acquisition azimuth of the target star at each moment, Indicates the azimuth correction value corresponding to the previous moment, Indicates the measured azimuth of the GNSS baseline, Indicates the theoretical azimuth of the target star at each moment; Indicates the acquisition pitch angle of the target star at each moment, Indicates the pitch angle correction value corresponding to the previous moment, Indicates the theoretical pitch angle of the target star at each moment; The obtaining of the azimuth error value and the pitch error value corresponding to each moment includes: The difference between the theoretical azimuth angle at each moment and the corresponding actual azimuth angle is recorded as the azimuth angle error value corresponding to each moment; the difference between the theoretical pitch angle at each moment and the corresponding actual pitch angle is recorded as the pitch angle error value corresponding to each moment; The obtaining of the azimuth angle correction value and the pitch angle correction value corresponding to each moment includes: The difference between the azimuth correction value corresponding to the previous moment and the azimuth error value corresponding to each moment is used as the azimuth correction value corresponding to each moment; the difference between the pitch correction value corresponding to the previous moment and the pitch error value corresponding to each moment is used as the pitch correction value corresponding to each moment; the optimal theoretical azimuth angle and the optimal theoretical pitch angle are used as the optimal parameters for adjusting the turntable to determine the high-precision initial pointing of the laser communication terminal.

2. A high-precision initial pointing method for a ground-based fixed-point laser communication terminal according to claim 1, characterized in that: The step of obtaining the acquisition azimuth and elevation angle of the target star at each moment includes: The azimuth and pitch angles of the target star at each moment are obtained through STK software, and are recorded as the acquisition azimuth and acquisition pitch angles of the target star at each moment, respectively.

3. A high-precision initial pointing system for a ground-based fixed-point laser communication terminal, characterized in that: It includes a measurement module, a theoretical calculation module and an error correction module. When the measurement module, the theoretical calculation module and the error correction module are executed, a high-precision initial pointing method for a ground-based fixed-point laser communication terminal as described in claim 1 is implemented.

4. An electronic device, characterized in that: It includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements a high-precision initial pointing method for a ground-based fixed-point laser communication terminal as described in any one of claims 1-2.

5. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the high-precision initial pointing method for a ground-based fixed-point laser communication terminal as described in any one of claims 1-2.

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