Satellite-borne laser communication load system with advanced aiming function and advanced aiming method

Abstract

The invention relates to the technical field of space optical communication optical design and control, in particular to a satellite-borne laser communication load system with an advanced aiming function and an advanced aiming method. The method comprises the steps that the relation between a fine tracking fast reflecting mirror and an advanced aiming angle, the mapping relation between light spot coordinates of an APS detector and the conversion relation between nutation mirrors are calibrated in sequence; and establishing a relation between the light spot coordinate of the detector and the advanced aiming angle and a relation between the compensation angle of the nutation mirror and the advanced aiming angle in sequence. According to the method, a fine tracking fast reflecting mirror, a nutation mirror, an APS detector and coupling light power feedback in a satellite-borne laser communication load are utilized, a cooperative working method is designed, and the advanced aiming function of a transmitting light path is achieved on the premise that an advanced aiming mechanism is not arranged. The complexity of an optical system is effectively reduced, system integration and adjustment are facilitated, and meanwhile the original fine tracking function and nutation coupling function of the system are guaranteed. The method is suitable for different scenes such as satellite-ground communication and inter-satellite communication.

Description

Technical Field

[0001] The present invention relates to the field of optical design and control technology for space optical communication, and in particular to a satellite-borne laser communication payload system with advance aiming and an advance aiming method. Background Art

[0002] In recent years, my country's space technology has developed rapidly. The massive amount of data transmission in orbit has put forward an urgent demand for high-speed communication technology between satellites and between satellites and the ground. Satellite laser communication technology has flourished accordingly. Satellite laser communication technology is a satellite communication technology that uses laser beams as information carriers. Since the frequency of light waves is several orders of magnitude higher than that of microwaves, satellite optical communication has a higher transmission rate. In addition, satellite optical communication can compress the light beam into a very small range, and has the characteristics of good confidentiality, strong anti-electromagnetic interference ability, and higher communication security.

[0003] In space optical communication, the distance of light beam transmission is very large, which will produce a certain relaxation time. Due to the relative motion between satellites and between satellites and the ground, the aiming operation will be affected by this relaxation time. Therefore, when performing the tracking and aiming process, the relaxation time needs to be taken into account, and the angle deviation of the communication beam in the tracking direction needs to be compensated according to the position and speed of the two relatively moving communication terminals. This process is called advance aiming.

[0004] A typical satellite-borne laser communication payload optical path usually includes multiple actuators. Generally, an advance aiming mirror is used to achieve advance aiming of the transmitting optical path, a precision tracking fast-reflection mirror is used to achieve precision tracking of the receiving optical path, and a nutating mirror is used to improve the nutation coupling efficiency of the receiving optical path. However, this design requires the use of three different actuators. Considering factors such as mass, volume, power consumption, and cost, it is a very meaningful technical issue to reduce the number of actuators while achieving the above functions.

[0005] Several improvements have been proposed in the prior art, including: (1) Intersatellite communication improvements: Simplification is achieved by combining functional mechanisms without improving algorithms and principles; the drawback of this type of solution is that it simply combines two mechanisms with different functions without fundamentally simplifying the actuators; and the system design of this type of device is relatively complex, making it difficult to apply widely. (2) Satellite-to-ground communication improvements: 1) Using the GPS data of the satellite platform and the data of the attitude measurement system, combined with the optical path structure of the current communication terminal, the imaging position of the beacon light on the precision tracking camera during the advance aiming of the communication light is calculated, and this is used as the dynamic tracking center of the precision tracking system. The precision tracking system controls the deflection of the fast tilt mirror so that the emission direction of the communication light deviates from the optical axis of the beacon light, thereby achieving advance aiming. This solves the problems of high resource consumption, complex system and loss of communication optical power caused by the use of an independent advance aiming system. 2) Satellite-to-ground communication improvements: It includes two-level tracking mechanisms, precision tracking and high-precision tracking, and the advance aiming function can be achieved through a fast reflection mirror, and can be used for the laser communication function transformation of various optical ground stations. However, a typical laser communication system optical path generally includes a nutating mirror to ensure the coupling efficiency of the communication beam entering the receiving optical fiber. The methods in the above two inventions do not compensate for the nutating coupling optical path when adjusting the tracking center and the precision tracking fast-reflection mirror, which will reduce the coupling efficiency entering the receiving optical fiber and thus affect the communication quality. In addition, the above two inventions generally focus on satellite-to-ground communication scenarios and lack coverage of inter-satellite communication scenarios.

[0006] Based on this, how to propose a method that can reduce the complexity of the optical system, adapt to different scenarios such as satellite-to-ground communication and inter-satellite communication, and realize the advance aiming function of the transmitting optical path while simplifying the number of mechanisms has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defects existing in the above-mentioned prior art, thereby providing a satellite-borne laser communication payload system with advance aiming and an advance aiming method.

[0008] A satellite-borne laser communication payload system with advance aiming includes: an optical antenna, a precision tracking fast-reflection mirror, a color separation plate, an emission collimator, a filter, a beam splitter, an APS detector, a nutating mirror, a fiber coupler, a capture tracking control module, a communication unit, and an attenuation plate and a cone arranged on the transmission light path of the color separation plate; The optical fiber signal emitted by the communication unit is collimated by the emission collimator to obtain an emission space beam, which is emitted after passing through the color separation plate, the precision tracking fast reflection mirror and the optical antenna in sequence; After the receiving space beam passes through the optical antenna, precision tracking fast reflection mirror, color separation plate, filter and beam splitter in sequence, a part of it enters the APS detector to form a light spot, and the other part enters the fiber coupler after being reflected by the nutating mirror, and further enters the communication unit through forming an optical fiber signal; The capture tracking control module is respectively connected with the precise tracking fast reflection mirror, the APS detector and the communication unit by electrical signals.

[0009] The invention discloses an advance aiming method for a satellite laser communication payload without an advance aiming mechanism, a collaborative working method for designing a precise tracking fast reflection mirror, a nutating mirror and an APS detector in a satellite laser communication payload system with advance aiming, and improves the advance aiming method, specifically comprising the following steps: S1. Calibrate the relationship between the precise tracking fast-reflection mirror and the advance aiming angle, and obtain the parameters required for linear fitting based on the calibration test record results; S2. Calibrate the mapping relationship between the precision tracking fast mirror and the APS detector spot coordinates to obtain the parameters required for linear fitting based on the calibration test record results; S3. Calibrate the conversion relationship between the precision tracking fast-reflection mirror and the nutating mirror, and obtain the parameters required for linear fitting based on the calibration test record results; S4. Establishing the relationship between the detector spot coordinates and the advance aiming angle; S5. Establish the relationship between the nutating mirror compensation angle and the advance aiming angle.

[0010] Preferably, calibrating the relationship between the precise tracking fast-reflection mirror and the advance aiming angle specifically comprises the following steps: Build a test environment, use one end of a collimator to receive the outgoing light emitted from the optical antenna, and use a receiving camera at the other end of the collimator to image the outgoing light to form a light spot; Adjust the precision tracking fast-reflection mirror to the zero position of the stroke, and record the coordinates of the light spot on the receiving camera when it is initially at the zero position of the stroke; The x-axis and y-axis of the precision tracking fast reflex mirror are controlled separately to traverse the entire stroke based on the preset step size. At the same time, the coordinates of the light spot in the receiving camera corresponding to different angles of the x-axis and y-axis of the precision tracking fast reflex mirror are recorded, and converted into angle values ​​and substituted into the corresponding rotation angle formula of the precision tracking fast reflex mirror to obtain the parameters required for linear fitting based on the calibration test record results.

[0011] Preferably, calibrating the mapping relationship between the fine tracking fast reflection mirror and the APS detector spot coordinates specifically includes the following steps: Set up a test environment and emit test light into the optical antenna through a collimator so that the light spot is imaged in the center area of ​​the APS detector; The x-axis and y-axis of the precision tracking fast reflex mirror are controlled separately to traverse the entire stroke based on the preset step size. At the same time, the coordinates of the light spot in the APS detector corresponding to different angles of the x-axis and y-axis of the precision tracking fast reflex mirror are recorded, and converted into angle values ​​and substituted into the corresponding rotation angle formula of the precision tracking fast reflex mirror to obtain the parameters required for linear fitting based on the calibration test record results.

[0012] Preferably, calibrating the conversion relationship between the precise tracking fast-reflection mirror and the nutating mirror specifically includes the following steps: Set up a test environment and emit test light into the optical antenna through a collimator; Place the precision tracking fast reflection mirror and the nutating mirror at their own travel zero position, and adjust the test turntable so that the emission spot is located in the middle of the APS detector field of view, and the light beam connected to the coupling fiber is also located at the center of the fiber; Adjust the position of the nutating mirror and use an optical power meter to measure the optical power value of the coupled optical fiber until the maximum optical power value is found, and record the position of the fine tracking fast mirror, the nutating mirror position and the optical power value at this time; Keep the precise tracking fast-reflection mirror and the nutating mirror in place, rotate the precise tracking fast-reflection mirror on the x-axis and the nutating mirror on the x-axis and y-axis, so that the input optical power value is always the maximum value recorded, and record the rotation angle of the nutating mirror at this time; The x-axis and y-axis of the precision tracking fast reflex mirror are controlled separately to traverse the entire stroke based on the preset step size. At the same time, the rotation angles of the nutating mirror corresponding to different angles of the x-axis and y-axis of the precision tracking fast reflex mirror are recorded, and the corresponding rotation angle formula of the precision tracking fast reflex mirror is substituted to obtain the parameters required for linear fitting according to the calibration test record results.

[0013] Preferably, establishing the relationship between the detector spot coordinates and the advance aiming angle specifically includes the following steps: According to steps S1 and S2, the parameters required for linear fitting according to the corresponding calibration test record results are obtained, and the relationship expression between the APS detector spot coordinates and the advance aiming angle is obtained; On the premise that the required advance aiming angle is known, the adjustment amount required for the communication precision tracking center point is calculated based on the relationship expression between the APS detector spot coordinates and the advance aiming angle.

[0014] Establish the relationship between the nutating mirror compensation angle and the advance aiming angle, specifically including: According to step S1 and step S3, the parameters required for linear fitting according to the corresponding calibration test record results are obtained, and the relationship expression between the nutating mirror compensation angle and the advance aiming angle is obtained; Under the premise that the required advance aiming angle is known, the adjustment compensation amount required for the nutating mirror is calculated according to the relationship expression between the nutating mirror compensation angle and the advance aiming angle.

[0015] Preferably, the method further includes: S6. adjusting the nutating mirror to achieve refined nutating coupling.

[0016] The technical solution of the present invention has the following advantages: The advance aiming method of the present invention utilizes the precision tracking fast reflection mirror, nutation mirror, APS detector and coupled optical power feedback in the satellite-borne laser communication payload, designs a collaborative working method, and realizes the advance aiming function of the transmitting optical path without an advance aiming mechanism. It effectively reduces the complexity of the optical system, facilitates system integration and adjustment, simplifies the number of actuators of the satellite-borne laser communication payload system, and ensures the original precision tracking function and nutation coupling function of the system. It is suitable for different scenarios such as satellite-to-ground communication and intersatellite communication. The method is simple and easy to implement in engineering, and has great practical engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic flow chart of the advance aiming method of the present invention; Figure 2 It is a schematic diagram of an existing typical optical system of a laser communication payload containing an advance aiming mechanism; Figure 3 This is a schematic diagram of the satellite-borne laser communication payload system of the present invention.

[0019] Description of reference numerals: 1-optical antenna; 2-precision tracking fast-reflection mirror; 3-capture tracking control module; 4-communication unit; 5-corner cone; 6-attenuation plate; 7-color separation plate; 8-emission collimator; 9-filter; 10-beam splitter; 11-APS detector; 12-nutating mirror; 13-fiber coupler; 14-advance aiming mechanism. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments 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 creative work are within the scope of protection of the present invention.

[0021] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Example 1 like Figure 3 The present embodiment includes a satellite-borne laser communication payload system with advance aiming, and Figure 2 Compared with the schematic diagram of the optical system of the existing typical laser communication payload containing the advance aiming mechanism 14, it is obvious that the advance aiming mechanism 14 is not set; in addition, the system of this embodiment can be carried on a satellite platform with an altitude of 500km near the earth to realize inter-satellite and satellite-to-ground laser communication functions. The communication wavelength is 1550nm, and the communication beam divergence is 50urad. The working strokes of the precision tracking fast reflection mirror 2 and the nutating mirror 12 are both ±2mrad, and the response time is less than 1ms. The receiving field of view of the APS detector 11 is greater than 5mrad, the number of full-window pixels is 1024*1024, and it supports 128*128 window use. The communication unit 4 in the system needs to have the function of receiving beam optical power detection and feedback.

[0025] The satellite-borne laser communication payload system with advance aiming in this embodiment includes: an optical antenna 1, a precision tracking fast reflection mirror 2, a color separation plate 7, an emission collimator 8, a filter 9, a beam splitter 10, an APS detector 11, a nutating mirror 12, a fiber coupler 13, a capture tracking control module 3, a communication unit 4, and an attenuation plate 6 and a pyramid 5 arranged on the transmission light path of the color separation plate 7; The optical fiber signal emitted by the communication unit 4 is collimated by the emission collimator 8 to obtain an emission spatial beam, which is emitted after passing through the color separation plate 7, the fine tracking fast reflection mirror 2 and the optical antenna 1 in sequence; After the receiving space light beam passes through the optical antenna 1, the precision tracking fast reflection mirror 2, the color separation plate 7, the filter 9 and the beam splitter 10 in sequence, a part of it enters the APS detector 11 to form a light spot, and the other part enters the fiber coupler 13 after being reflected by the nutating mirror 12, and further enters the communication unit 4 to realize information communication by forming an optical fiber signal; The capture tracking control module 3 is electrically connected to the fine tracking fast reflection mirror 2 , the APS detector 11 and the communication unit 4 , respectively.

[0026] Example 2 The method for pre-aiming a satellite-borne laser communication payload without a pre-aiming mechanism utilizes the precise tracking fast-reflecting mirror 2, the nutating mirror 12, and the APS detector 11 in the satellite-borne laser communication payload system with pre-aiming in Example 1 to design a collaborative working method, improve the pre-aiming method, and realize the pre-aiming function of the transmitting optical path without a pre-aiming mechanism, specifically comprising the following steps: Figure 1 As shown: S1. Calibrate the relationship between the precise tracking fast-reflection mirror 2 and the advance aiming angle, and obtain the parameters required for linear fitting based on the calibration test record results; S2. Calibrate the mapping relationship between the fine tracking fast mirror 2 and the APS detector 11 spot coordinates, and obtain the parameters required for linear fitting based on the calibration test record results.; S3 calibration fine tracking fast mirror 2 and nutating mirror conversion relationship between 12, to obtain the parameters required for linear fitting based on the calibration test record results; S4. Establishing the relationship between the detector spot coordinates and the advance aiming angle; S5. Establish the relationship between the compensation angle of the nutating mirror 12 and the advance aiming angle.

[0027] Specifically: In this embodiment, step S1. calibrating the relationship between the precise tracking fast reflection mirror 2 and the advance aiming angle specifically includes the following steps: A test environment is set up, and one end of a collimator is used to receive the outgoing light emitted from the optical antenna 1, and a receiving camera is used at the other end of the collimator to image the outgoing light to form a light spot; Adjust the fine tracking fast-reflection mirror 2 to the zero position of the stroke, and record the coordinates of the light spot on the receiving camera when it is initially at the zero position of the stroke; Separately control the x-axis and y-axis of the precision tracking fast reflex mirror 2 to traverse the entire stroke based on the preset step length; wherein, the step length is set to 200urad until it is fully traveled to form a 2mrad position; at the same time, record the corresponding light spot coordinates in the receiving camera at different angles of the x-axis and y-axis of the precision tracking fast reflex mirror 2, and convert them into angle values ​​and substitute them into the corresponding rotation angle formula of the precision tracking fast reflex mirror 2 to obtain the parameters required for linear fitting based on the calibration test record results. Specifically, according to the focal length and pixel size of the camera and other parameters, the difference in light spot coordinates is converted into the difference in angle values; The corresponding results of the rotation angles of the x and y axes of the precise tracking fast-reflecting mirror 2 and the angle changes in the receiving camera are calculated based on the angle values ​​obtained in step S1: ; In the formula, ( , ) is the advance aiming angle, specifically the angle value corresponding to the number of pixels of the receiving camera spot change; ( , ) is the rotation angle corresponding to the precise tracking fast-reflection mirror 2, , , , is the desired parameter.

[0028] In this embodiment, step S2. calibrating the mapping relationship between the fine tracking fast reflection mirror 2 and the spot coordinates of the APS detector 11 specifically includes the following steps: Build a test environment, and emit test light into the optical antenna 1 through a collimator so that the light spot is imaged in the central area of ​​the APS detector 11. The number of full-window pixels is 1024*1024, and the center point is 512, 512; The x-axis and y-axis of the precise tracking fast reflex mirror 2 are controlled to traverse the entire stroke based on the preset step length, and the corresponding APS detector 11 light spot coordinates at different angles of the x-axis and different angles of the y-axis of the precise tracking fast reflex mirror 2 are recorded, and converted into the number of pixels of the APS detector light spot change and substituted into the formula of the corresponding rotation angle of the precise tracking fast reflex mirror 2 to obtain the parameters required for linear fitting according to the calibration test record results. Specifically, in this embodiment, the Y-axis of the precise tracking fast reflex mirror 2 is kept at zero position, and the X-axis is rotated so that the light spot coordinates move from one boundary to another. The step length is set to 200urad, and the entire stroke is traversed, and the corresponding APS detector 11 light spot coordinates at different angles of the x-axis of the precise tracking fast reflex mirror 2 are recorded; the same operation is performed on the y-axis. According to the obtained number of pixels of the APS detector light spot change, the corresponding results of the rotation angles of the x- and y-axis of the precise tracking fast reflex mirror 2 and the APS light spot coordinates are calculated: ; In the formula, ( , ) is the number of pixels of the APS detector spot change, ( , ) is the rotation angle corresponding to the precise tracking fast-reflection mirror 2, , , , is the desired parameter.

[0029] In this embodiment, step S3 of calibrating the conversion relationship between the precise tracking fast-reflection mirror 2 and the nutating mirror 12 specifically includes the following steps: A test environment is set up, and a test light is emitted into the optical antenna 1 through a collimator; Place the precision tracking fast reflection mirror 2 and the nutating mirror 12 at their own travel zero positions, and adjust the test turntable so that the emission spot is located at 512, 512 in the middle of the field of view of the APS detector 11, and the light beam connected to the coupling optical fiber is also located at the center of the optical fiber; The position of the nutating mirror 12 is continuously adjusted and the optical power value of the coupled optical fiber is measured using an optical power meter until the position of the maximum optical power value is found, and the position of the precise tracking fast-reflecting mirror 2, the position of the nutating mirror 12 and the optical power value at this time are recorded; Keep the precise tracking fast-reflection mirror 2 and the nutating mirror 12 in place, randomly rotate the x-axis of the precise tracking fast-reflection mirror 2 to a certain angle, and rotate the x-axis and y-axis of the nutating mirror 12, so that the access optical power value is always the maximum value recorded, and record the rotation angle of the nutating mirror 12 at this time; The x-axis and y-axis of the precise tracking fast reflex mirror 2 are controlled to traverse the entire stroke based on the preset step length, and the corresponding rotation angles of the nutating mirror 12 under different x-axis and y-axis angles of the precise tracking fast reflex mirror 2 are recorded, and the corresponding rotation angle formula of the precise tracking fast reflex mirror 2 is substituted to obtain the parameters required for linear fitting according to the calibration test record results. Specifically, the corresponding results of the x-axis and y-axis rotation angles of the precise tracking fast reflex mirror 2 and the rotation angle of the nutating mirror 12 are calculated according to the rotation results of the nutating mirror 12; ; In the formula, ( , ) is the rotation angle of the nutating mirror 12, ( , ) is the rotation angle corresponding to the precise tracking fast-reflection mirror 2, , , , is the desired parameter.

[0030] In this embodiment, S4. establishing the relationship between the detector spot coordinates and the advance aiming angle specifically includes the following steps: According to steps S1 and S2, the parameters required for linear fitting based on the corresponding calibration test record results are obtained, and the relationship expression between the spot coordinates of the APS detector 11 and the advance aiming angle is obtained: ; After finishing, we can get: ; On the premise that the required advance aiming angle is known, the adjustment amount required for the communication precision tracking center point is calculated according to the relationship expression between the APS detector 11 spot coordinates and the advance aiming angle.

[0031] In addition, the APS detector 11 is windowed here, and the window size is usually set to 128×128 pixels, so the preset center coordinates of the detector are 64, 64. After calculation, the advance aiming angle required for the communication task is , you need to adjust the precision tracking center to 64+ .

[0032] In this embodiment, S5. establishing the relationship between the compensation angle of the nutating mirror 12 and the advance aiming angle specifically includes: According to step S1 and step S3, the parameters required for linear fitting according to the corresponding calibration test record results are obtained, and the relationship expression between the compensation angle of the nutating mirror 12 and the advance aiming angle is obtained: ; After finishing, we can get: ; Under the premise that the required advance aiming angle is known, the adjustment compensation amount required by the nutating mirror 12 is calculated according to the relationship expression between the compensation angle of the nutating mirror 12 and the advance aiming angle. If the advance aiming angle required for the communication task is calculated, , then the adjustment amount that the nutating mirror 12 needs to make based on the original position is .

[0033] like Figure 1 , in this embodiment, it also includes: S6. adjusting the nutating mirror 12 to achieve refined nutating coupling; In actual operation, the coupling efficiency of the receiving optical fiber is adjusted by finely adjusting the position of the nutating mirror 12, so as to realize the nutating coupling more finely to compensate for the influence of vibration, thermal deformation, etc. on the coupling efficiency; Specifically, the current calculated nutation position is taken as the starting point, the traversal step is 0.5 pixel size, and each point is stopped for 100ms during the traversal process to obtain accurate and stable feedback of the optical power value. A total of 100 points are traversed to cover the possible deviation range. The nutating mirror 12 performs rectangular spiral scanning traversal with equal steps in the x and y directions. During this process, the traversal position and the corresponding received optical power value are recorded. The position of the nutating mirror 12 corresponding to the point with the maximum optical power value during the nutation process is used as the final position of the nutating mirror 12 to establish a communication task.

[0034] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A satellite-borne laser communication payload system with advance aiming, characterized in that: include: An optical antenna (1), a precision tracking fast-reflecting mirror (2), a color separation plate (7), an emission collimator (8), a filter (9), a beam splitter (10), an APS detector (11), a nutating mirror (12), a fiber coupler (13), a capture tracking control module (3), a communication unit (4), and an attenuation plate (6) and a cone (5) arranged on the transmission light path of the color separation plate (7); The optical fiber signal emitted by the communication unit (4) is collimated by a transmitting collimator (8) to obtain a transmitting spatial light beam, a portion of which passes through a color separation plate (7), a precision tracking fast reflection mirror (2) and an optical antenna (1) in sequence and is emitted, and another portion of which passes through a color separation plate (7), an attenuation plate (6) and a corner cone (5) in sequence; After the received spatial light beam passes through the optical antenna (1), the precision tracking fast reflection mirror (2), the color separation plate (7), the filter (9) and the beam splitter (10) in sequence, a portion of the light beam enters the APS detector (11) to form a light spot, and another portion of the light beam enters the optical fiber coupler (13) after being reflected by the nutating mirror (12), and further forms an optical fiber signal to enter the communication unit (4); The capture tracking control module (3) is respectively connected to the fine tracking fast reflection mirror (2), the APS detector (11) and the communication unit (4) via electrical signals.

2. A method for pre-aiming a satellite-borne laser communication payload without a pre-aiming mechanism, characterized in that: A method for designing a collaborative working method using the precision tracking fast-reflection mirror (2), the nutating mirror (12) and the APS detector (11) in the satellite-borne laser communication payload system with advance aiming as described in claim 1 is used to improve the advance aiming method, specifically comprising the following steps: S1. Calibrate the relationship between the precision tracking fast-reflection mirror (2) and the advance aiming angle, and obtain the parameters required for linear fitting based on the calibration test record results; S2. Calibrate the mapping relationship between the fine tracking fast mirror (2) and the APS detector (11) spot coordinates, and obtain the parameters required for linear fitting based on the calibration test record results; S3. Calibrate the conversion relationship between the precision tracking fast-reflecting mirror (2) and the nutating mirror (12), and obtain the parameters required when performing linear fitting based on the calibration test record results; S4. Establishing the relationship between the detector spot coordinates and the advance aiming angle; S5. Establishing the relationship between the compensation angle of the nutating mirror (12) and the advance aiming angle.

3. The method for pre-aiming a satellite-borne laser communication payload without a pre-aiming mechanism according to claim 2, characterized in that: The relationship between the precision tracking fast reflection mirror (2) and the advance aiming angle is calibrated, specifically including the following steps: A test environment is set up, and an outgoing light beam emitted from the optical antenna (1) is received at one end of a collimator, and an outgoing light beam is imaged by a receiving camera at the other end of the collimator to form a light spot; Adjust the fine tracking fast-reflection mirror (2) to the zero position of the travel, and record the coordinates of the light spot on the receiving camera when it is initially at the zero position of the travel; The x-axis and y-axis of the precision tracking fast reflex mirror (2) are controlled to traverse the entire stroke based on a preset step length, and the light spot coordinates in the receiving camera corresponding to different x-axis angles and y-axis angles of the precision tracking fast reflex mirror (2) are recorded and converted into angle values ​​and substituted into the corresponding rotation angle formula of the precision tracking fast reflex mirror (2) to obtain the parameters required for linear fitting based on the calibration test record results.

4. The method for advance aiming of a satellite-borne laser communication payload without an advance aiming mechanism according to claim 2, characterized in that: Calibration of the mapping relationship between the fine tracking fast reflection mirror (2) and the light spot coordinates of the APS detector (11) specifically includes the following steps: A test environment is set up, and a test light is emitted into the optical antenna (1) through a collimator so that the light spot is imaged in the central area of ​​the APS detector (11); The x-axis and y-axis of the precision tracking fast reflex mirror (2) are controlled to traverse the entire stroke based on a preset step length, and the coordinates of the light spot in the APS detector (11) corresponding to different angles of the x-axis and different angles of the y-axis of the precision tracking fast reflex mirror (2) are recorded, and converted into the number of pixels of the light spot change of the APS detector and substituted into the corresponding rotation angle formula of the precision tracking fast reflex mirror (2), so as to obtain the parameters required for linear fitting based on the calibration test record results.

5. The method for advance aiming of a satellite-borne laser communication payload without an advance aiming mechanism according to claim 2, characterized in that: The conversion relationship between the precision tracking fast reflection mirror (2) and the nutating mirror (12) is calibrated, and specifically comprises the following steps: A test environment is set up, and a test light is emitted into the optical antenna (1) through a collimator; The precision tracking fast reflection mirror (2) and the nutating mirror (12) are both placed at their own travel zero positions, and the test turntable is adjusted so that the emission light spot is located in the middle of the field of view of the APS detector (11), and the light beam connected to the coupling optical fiber is also located at the center of the optical fiber; Adjust the position of the nutating mirror (12) and use an optical power meter to measure the optical power value of the coupled optical fiber until the position of the maximum optical power value is found, and record the position of the fine tracking fast reflection mirror (2), the position of the nutating mirror (12) and the optical power value at this time; Keeping the positions of the precise tracking fast-reflection mirror (2) and the nutating mirror (12) fixed, rotating the precise tracking fast-reflection mirror (2) about the x-axis and rotating the nutating mirror (12) about the x-axis and y-axis, so that the input optical power value is always the maximum value recorded, and recording the rotation angle of the nutating mirror (12) at this time; The x-axis and y-axis of the precision tracking fast reflex mirror (2) are controlled to traverse the entire stroke based on a preset step length, and the rotation angles of the nutating mirror (12) corresponding to different x-axis angles and y-axis angles of the precision tracking fast reflex mirror (2) are recorded, and the corresponding rotation angle formula of the precision tracking fast reflex mirror (2) is substituted into the formula to obtain the parameters required for linear fitting based on the calibration test record results.

6. The method for advance aiming of a satellite-borne laser communication payload without an advance aiming mechanism according to claim 2, characterized in that: Establishing the relationship between the detector spot coordinates and the advance aiming angle includes the following steps: According to steps S1 and S2, the parameters required for linear fitting based on the corresponding calibration test record results are obtained, and the expression for the relationship between the light spot coordinates of the APS detector (11) and the advance aiming angle is obtained; Under the premise that the required advance aiming angle is known, the adjustment amount required for the communication precision tracking center point is calculated according to the relationship expression between the light spot coordinates of the APS detector (11) and the advance aiming angle.

7. The method for pre-aiming a satellite-borne laser communication payload without a pre-aiming mechanism according to claim 2, characterized in that: Establishing the relationship between the compensation angle of the nutating mirror (12) and the advance aiming angle, specifically including: According to step S1 and step S3, the parameters required for linear fitting according to the corresponding calibration test record results are obtained, and the relationship expression between the compensation angle of the nutating mirror (12) and the advance aiming angle is obtained; On the premise that the required advance aiming angle is known, the adjustment compensation amount required for the nutating mirror (12) is calculated according to the relationship expression between the compensation angle of the nutating mirror (12) and the advance aiming angle.

8. The method for advance aiming of a satellite-borne laser communication payload without an advance aiming mechanism according to claim 2, characterized in that: Also includes: S6. Adjust the nutation mirror (12) to achieve fine nutation coupling.

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