Opto-mechanical system for inter-satellite laser communication terminal

Abstract

Provided in the present invention is an opto-mechanical system for an inter-satellite laser communication terminal, the system comprising: an optical path unit, wherein the optical path unit comprises a single-axis oscillating mirror, and the single-axis oscillating mirror scans in a first mode received light from another inter-satellite laser communication terminal; and a tracking and pointing receiving unit, wherein, upon detecting the received light from the optical path unit, the tracking and pointing receiving unit determines a light spot position of the received light. The optical path unit is further configured to, after the light spot position of the received light is determined, adjust the deflection direction of the single-axis oscillating mirror so as to guide the light spot position to the center of the tracking and pointing receiving unit and scan the received light in a second mode, the scanning angle of the second mode being less than that of the first mode, and the scanning frequency of the second mode being higher than that of the first mode. The opto-mechanical system of the present invention is implemented using discrete devices, thereby improving the layout flexibility and simplifying the opto-mechanical configuration.

Description

Optomechanical system for inter-satellite laser communication terminals Technical Field

[0001] This invention relates generally to the field of inter-satellite communication, and more specifically, to an optomechanical system for an inter-satellite laser communication terminal. Background Technology

[0002] Currently, with the continuous development of satellite technology and the increasing number of satellite application scenarios, multiple low-Earth orbit satellite networks have emerged or are planned. In these networks, inter-satellite communication (IPC) has become a key technology restricting network performance. Compared to microwave IPC, laser communication offers advantages such as high bandwidth, light weight, small size, and freedom from electromagnetic spectrum limitations, making it a necessary means to solve the problem of high-speed data transmission in future space. Furthermore, compared to high-speed IPC technology, low-speed, low-cost, and large-scale IPC technology offers more significant advantages in deployment and application, with a marked reduction in complexity. Therefore, it is more suitable as a transitional technology between microwave IPC and high-speed IPC, and has significant practical implications for the large-scale commercial application of IPC.

[0003] Therefore, the design of inter-satellite laser communication terminals carried on satellites for inter-satellite communication has become a hot topic in the field of inter-satellite laser communication technology.

[0004] Currently, the high-speed transmission design of inter-satellite laser communication terminals is complex, costly, and cannot be applied on a large scale. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides an inter-satellite laser communication terminal, and more specifically, an optomechanical system for an inter-satellite laser communication terminal, which improves layout flexibility and simplifies optomechanical composition by using discrete components.

[0006] According to one aspect of the present invention, an optomechanical system for an inter-satellite laser communication terminal is provided, comprising: an optical path unit including a single-pendulum mirror that scans received light from another inter-satellite laser communication terminal in a first mode; and a tracking and aiming receiving unit that, upon detecting received light from the optical path unit, determines the spot position of the received light, wherein the optical path unit is further configured to, after determining the spot position of the received light, adjust the deflection direction of the single-pendulum mirror to guide the spot position to the center of the tracking and aiming receiving unit and scan the received light in a second mode, wherein the scanning angle of the second mode is smaller than that of the first mode, and the scanning frequency of the second mode is higher than that of the first mode.

[0007] In some implementations, the optical path unit includes a receiving optical path, which includes a single-pendulum mirror, a transceiver antenna mirror group, a dichroic mirror, a dual narrowband filter, and a beam splitter arranged sequentially according to the direction of travel of the received light. The transceiver antenna mirror group ablates the received light from the single-pendulum mirror and transmits it to the dichroic mirror. The dichroic mirror transmits the received light and sends it to the dual narrowband filter. The dual narrowband filter transmits the received light and transmits it to the tracking and aiming receiving unit via the beam splitter.

[0008] In some implementations, the tracking receiver unit includes a four-quadrant avalanche photodiode detector.

[0009] In some implementations, the optomechanical system further includes a communication receiving unit located downstream of the beam splitter for receiving the received light from the beam splitter.

[0010] In some implementations, the communication receiving unit includes an avalanche photodiode detector.

[0011] In some implementations, the optical path unit further includes a first reflector group located between the beam splitter and the communication receiving unit, for reflecting the received light so that the direction of the received light enters the communication receiving unit perpendicularly.

[0012] In some implementations, the optical path unit further includes a transmitting optical path, which is used to send transmitted light to the other inter-satellite laser communication terminal.

[0013] In some implementations, the optical transmission path includes: a transmitting mirror group, a fast reflector, a dichroic mirror, a transceiver antenna mirror group, and the pendulum mirror arranged sequentially according to the direction of travel of the transmitted light, wherein the transmitting mirror group transmits the transmitted light emitted by the laser, the fast reflector reflects the transmitted light to the dichroic mirror, the dichroic mirror reflects the transmitted light, the transceiver antenna mirror group expands the transmitted light reflected by the dichroic mirror, and transmits the expanded transmitted light via the pendulum mirror.

[0014] In some implementations, the receiving optical path further includes a second reflector group located between the transceiver antenna mirror group and the dichroic mirror, for reflecting the received light in the receiving optical path.

[0015] In some implementations, the transmitting optical path further includes a second reflector group located between the transceiver antenna mirror group and the dichroic mirror, for reflecting the transmitted light in the transmitting optical path.

[0016] In some implementations, the optomechanical system further includes an advance aiming unit that determines an advance control amount for the emitted light based on received light previously received from the other inter-satellite laser communication terminal, so as to pre-deflect the emitted light emitted by the laser.

[0017] The optomechanical system for inter-satellite laser communication terminals of the present invention not only improves the layout flexibility of the optomechanical system, but also simplifies the optomechanical components. Attached Figure Description

[0018] The invention will be better understood by referring to the description of specific embodiments of the invention given in the following figures, and other objects, details, features and advantages of the invention will become more apparent.

[0019] Figure 1 shows a schematic diagram of an exemplary satellite network according to an embodiment of the present invention.

[0020] Figure 2 shows a schematic diagram of the structure of an inter-satellite laser communication terminal according to some embodiments of the present invention.

[0021] Figure 3 shows a schematic diagram of the structure of an optical path unit according to an embodiment of the present invention.

[0022] Figure 4 shows a schematic diagram of the optical path of the optical path unit according to an embodiment of the present invention. Detailed Implementation

[0023] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be more thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0024] In the following description, certain specific details are set forth for the purpose of illustrating embodiments of the various inventions to provide a thorough understanding of these embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0025] Unless the context requires otherwise, throughout the specification and claims, the word “comprising” and its variations, such as “including” and “having”, shall be understood to have an open, inclusive meaning, that is, to be interpreted as “including, but not limited to”.

[0026] Throughout this specification, references to "one embodiment" or "some embodiments" indicate that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment. Therefore, the appearance of "in one embodiment" or "in some embodiments" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0027] Furthermore, the terms first, second, third, etc., used in the specification and claims are used only for clarity of description to distinguish between different objects, and do not limit the size or other order of the objects they describe, unless otherwise stated.

[0028] Figure 1 illustrates a schematic diagram of an exemplary satellite network according to an embodiment of the present invention. Figure 1 exemplarily shows two satellite orbits 1a and 2a around the Earth, wherein multiple satellites 1b and 2b are respectively arranged on satellite orbits 1a and 2a, and the multiple satellites 1b and 2b can communicate with each other in the same orbit.

[0029] Figure 1 illustrates an example of a co-orbital low-Earth orbit satellite network, with the orbit type being sun-synchronous orbits and an altitude range of 500 km. Several co-orbital laser communication terminals can be deployed on each satellite orbit to perform laser communication within a small angular maneuvering range and between co-orbital terminals. The relative positions of the laser communication terminals used for co-orbital laser communication are stable, with small relative maneuvering amplitudes and small required deflection angle ranges. The azimuth angle deflection range is (-90° to +90°), the elevation angle deflection range is (-10° to +10°), and the communication distance range is (300 km to 1500 km).

[0030] In addition, several, such as three, inter-orbit laser communication terminals can be deployed on each satellite orbit. These terminals are capable of transmitting information between different orbits over a wide range of maneuvers, such as enabling inter-orbit communication between satellite 1b on satellite orbit 1a and satellite 2b on satellite orbit 2a. In this paper, we will only describe the inter-satellite laser communication terminals on satellite 1b or 2b using intra-orbit communication as an example.

[0031] Figure 2 shows a schematic diagram of the structure of an inter-satellite laser communication terminal 100 according to some embodiments of the present invention. The inter-satellite laser communication terminal 100 can be located on satellites 1b and 2b, and is used for laser communication with other inter-satellite laser communication terminals 100 on other satellites in the same orbit.

[0032] As shown in Figure 2, the inter-satellite laser communication terminal 100 includes an optomechanical system 10 and a processing system 20. The optomechanical system 10 is used to search for and acquire another inter-satellite laser communication terminal 100 on another satellite in the same orbit, track and aim at that other inter-satellite laser communication terminal 100, and send and / or receive optical signals from that other inter-satellite laser communication terminal 100. The processing system 20 is used to receive optical signals from the other laser communication terminal 100, process the optical signals to parse the data carried by the optical signals, and / or process data to be sent to the other laser communication terminal 100 for modulation and transmission. Furthermore, the processing system 20 can also be used to implement various control strategies, manage peripheral devices, and drive the various actuators of the optomechanical system 10. In Figure 2, optical signals are shown as dashed lines, electrical signals as solid lines, and arrows indicate the direction of the optical or electrical signal flow.

[0033] Currently, the optomechanical system of inter-satellite laser communication terminals typically adopts a coarse-precision composite detection architecture consisting of an elevation motor, an azimuth motor, and a small-angle, high-frequency single pendulum mirror. This results in high costs for inter-satellite laser communication terminals and makes it difficult to achieve large-scale network deployment.

[0034] To address the aforementioned issues, in the optomechanical system 10 of the inter-satellite laser communication terminal 100 of the present invention, a single pendulum mirror supporting large angles is used to perform coarse scanning tracking and fine scanning tracking in different scanning modes, thereby reducing the system's hardware and software complexity and hardware cost.

[0035] As shown in Figure 2, the optomechanical system 10 includes an optical path unit 110, which includes a single-pendulum mirror 32 (described in detail below with reference to Figures 3 and 4). The single-pendulum mirror 32 can be a single-pendulum mirror that supports large-angle swinging, and can also be referred to herein as a large-angle single-pendulum mirror. When the inter-satellite laser communication terminal 100 enters the tracking scanning state, the single-pendulum mirror 32 scans the received light from another inter-satellite laser communication terminal 100 in a first mode. Here, the first mode can be a coarse scanning mode with a large scanning angle and a low scanning frequency. In the first mode, the single-pendulum mirror 32 can perform a spiral scan on an uncertain region to capture the incoming received light. Here, the large scanning angle is, for example, an angle range of ±5°, and the low scanning frequency is, for example, below 100Hz.

[0036] The optomechanical system 10 also includes a tracking and aiming receiving unit 120, which determines the position of the light spot when it detects the received light from the optical path unit 110.

[0037] By determining the position of the light spot received, the aiming receiver unit 120 can achieve coarse aiming at another inter-satellite laser communication terminal 100.

[0038] In some embodiments, the tracking receiver 120 may include a four-quadrant avalanche photodiode (QAPD) detector for detecting the received light and determining the position of the light spot. Here, the position of the light spot can be determined, for example, by imaging the received light onto the photosensitive surface of the tracking receiver 120.

[0039] After determining the position of the received light spot, the deflection direction of the pendulum mirror 32 is adjusted to guide the light spot position to the center of the tracking and aiming receiving unit 120 (e.g., to the center of the photosensitive surface of the QAPD detector). For example, the tracking and aiming receiving unit 120 or the processing system 20 can calculate the adjustment value of the deflection direction of the pendulum mirror 32 based on the deviation between the light spot position and the center of the tracking and aiming receiving unit 120, and control the pendulum mirror 32 to adjust according to the adjustment value.

[0040] When the position of the light spot is guided to the center of the tracking and aiming receiving unit 120, the tracking and aiming receiving unit 120 can determine that another inter-satellite laser communication terminal 100 has been scanned.

[0041] Then, the single-pendulum mirror 32 switches to the second mode for scanning. Here, the scanning angle in the second mode is smaller than that in the first mode, and the scanning frequency is higher than that in the first mode. That is, the second mode is a fine scanning mode with a small scanning angle range and a high scanning frequency, thereby enabling stable tracking of another inter-satellite laser communication terminal 100. Here, the small scanning angle is, for example, an angle range of 3 milliradians (mrad), and the high scanning frequency is, for example, on the order of 1000 Hz.

[0042] By using a single pendulum mirror 32 to perform rapid tracking at a small angle and high frequency, the position of the light spot can be locked at the center of the tracking and aiming receiving unit 120.

[0043] The optomechanical system 10 of another inter-satellite laser communication terminal 100 can perform similar operations until the two inter-satellite laser communication terminals 100 complete scanning, tracking, and locking onto each other. In this case, the two inter-satellite laser communication terminals 100 can enter the inter-satellite communication process, or the two inter-satellite laser communication terminals 100 can each send a tracking completion signal to the ground control system, and the ground control system, upon determining that both inter-satellite laser communication terminals 100 have completed tracking, sends a communication start signal to the two inter-satellite laser communication terminals 100, so that the two inter-satellite laser communication terminals 100 enter the inter-satellite communication process.

[0044] In addition, the optomechanical system 10 may also include a communication receiving unit 130, which detects the received light from the optical path unit 110 and transmits the received light to the processing system 20 when the received light is detected to process the received light and obtain the communication data carried therein.

[0045] Figure 3 shows a structural schematic diagram of the optical path unit 110 according to an embodiment of the present invention, and Figure 4 shows an optical path schematic diagram of the optical path unit 110 according to an embodiment of the present invention. The specific structure and operation of the optical path unit 110, as well as the working relationship between the optical path unit 110 and other components of the optomechanical system 10, are described below with reference to Figures 3 and 4.

[0046] According to the direction of light flow in the optical path unit 110 (i.e., whether it is receiving light or transmitting light), the optical path unit 110 can be further divided into a receiving optical path and a transmitting optical path. The receiving optical path is used to receive received light from another inter-satellite laser communication terminal 100, and the transmitting optical path is used to send transmitted light to another inter-satellite laser communication terminal 100.

[0047] As shown in Figures 3 and 4, the receiving optical path of the optical path unit 110 includes a single pendulum mirror 32, a transceiver antenna mirror group 33, a dichroic mirror 39, a dual narrowband filter 40, and a beam splitter 41 arranged in sequence according to the direction of the received light.

[0048] In addition, a solar filter 31 may be included before the single pendulum mirror 32. The solar filter 31 may be located at the light-passing aperture of the optical path unit 110 to filter out sunlight from all incoming light so as to retain only the laser light from other inter-satellite laser communication terminals 100 as the receiving light.

[0049] The transceiver antenna lens group 33 reduces the received light from the pendulum mirror 32 and transmits it to the dichroic mirror 39. Here, the transceiver antenna lens group 33 is used to proportionally enlarge (i.e., expand) or reduce (i.e., shrink) the diameter of the collimated input beam, and it may have, for example, a Keplerian or Galilean lens structure.

[0050] Dichroic mirror 39 transmits and receives light, then directs the received light into the dual narrowband filter 40. A dichroic mirror is an optical device with filtering capabilities, selectively transmitting light within a certain wavelength range while reflecting light within another range. In the receiving light path, dichroic mirror 39 transmits the received light, while in the emitting light path, it reflects the emitted light (as described below).

[0051] The dual narrowband filter 40 further transmits the received light and transmits it to the tracking receiver unit 120 via the beam splitter 41. The dual narrowband filter 40 can transmit the received light and attenuate the emitted light (if any emitted light leaks into the dual narrowband filter 40), thereby further improving the isolation between the emitted and received light paths.

[0052] Beam splitter 41 can split the received light into two different beams according to a ratio. One beam is transmitted to the tracking and aiming receiving unit 120 for acquisition and tracking by another inter-satellite laser communication terminal 100, and the other beam can be transmitted to the downstream communication receiving unit 130 for further analysis of the communication data carried in the received light.

[0053] In some embodiments, the communication receiving unit 130 may include an avalanche photodiode (APD) detector for detecting received light and, when the received light is detected, transmitting the received light to the processing system 20 for processing to obtain the communication data carried therein.

[0054] In some embodiments, as shown in Figures 3 and 4, the optical path unit 110 may further include a first reflector group (e.g., two reflectors 42 and 43 arranged in parallel intervals), the first reflector group being located between the beam splitter 41 and the communication receiving unit 130, for reflecting the received light so that the direction of the received light enters the communication receiving unit 130 perpendicularly.

[0055] Here, the arrangement of the first reflector group enables the control of the direction of light travel to match the installation position of the communication receiving unit 130, and makes the structure of the optical path unit 110 more compact.

[0056] In this way, the optical path unit 110 of the optomechanical system 10 of the present invention can detect the received light from another inter-satellite laser communication terminal 100 and transmit the received light to the tracking and aiming receiving unit 120 and the communication receiving unit 130, so that the tracking and aiming receiving unit 120 can lock with the other inter-satellite laser communication terminal 100 and the received light can be analyzed to determine the communication data carried therein.

[0057] As shown in Figures 3 and 4, the transmitting optical path includes a transmitting mirror group 37, a fast-reflecting mirror 38, a dichroic mirror 39, a transceiver antenna mirror group 33, and a single-pendulum mirror 32 arranged in sequence according to the direction of the transmitted light.

[0058] The emitting mirror group 37 can transmit the emitted light emitted by the laser (not shown in the figure).

[0059] The fast-reflecting mirror 38 reflects the emitted light from the emitting mirror group 37 to the dichroic mirror 39.

[0060] The dichroic mirror 39 reflects the emitted light to the transceiver antenna mirror group 33, which expands the emitted light reflected by the dichroic mirror 39 and then emits the expanded emitted light through the pendulum mirror 32.

[0061] Furthermore, as shown in Figure 2, the optomechanical system 10 may also include an advance aiming unit 140. The advance aiming unit 140 can determine the advance control amount of the emitted light based on satellite broadcast data from the current satellite (i.e., the satellite where the inter-satellite laser communication terminal 100 is located) and another satellite (i.e., the satellite where another inter-satellite laser communication terminal 100 is located), in order to pre-deflect the emitted light emitted by the laser. The satellite broadcast data may include at least the coordinates and velocities of the two satellites. The coordinates and velocity of the current satellite may be provided, for example, by the satellite platform of the current satellite (i.e., the components of the current satellite other than its payload), for example, by the telemetry, tracking, and command (TT&C) subsystem of the current satellite platform. The coordinates and velocity of the other satellite may be provided, for example, by the satellite platform of the other satellite to a ground station, and then by the ground station to the advance aiming unit 140 of the current satellite's inter-satellite laser communication terminal 100. More specifically, the advance aiming unit 140 can calculate the relative position change between the current satellite and the other satellite based on the coordinates and velocity of the current satellite and the coordinates and velocity of the other satellite, calculate the next position of the other satellite based on the relative position change, and determine the advance control amount based on the calculated next position, so that the transmitted light emitted by the optomechanical system 10 is ultimately directed to the next position.

[0062] In some embodiments, as shown in Figures 3 and 4, the optical path unit 110 may further include a second reflector group (e.g., two reflectors 34 and 35 arranged vertically apart), the second reflector group being located between the transceiver antenna mirror group 33 and the dichroic mirror 39, for reversing the received light in the receiving optical path and reversing the transmitted light in the transmitting optical path.

[0063] Here, the arrangement of the second reflector group makes the structure of the optical path unit 110 more compact.

[0064] Note that although the embodiments of Figures 3 and 4 show the first and second mirror groups, those skilled in the art will understand that these mirror groups are only set up to control the direction of the optical path so that the optical path unit 110 is compact and occupies less area. Without limiting the size of the optical path unit 110 or the optomechanical system 10, the optical path unit 110 may not include such mirror groups or may only include one of them.

[0065] In the structure of the optical path unit 110 shown in Figures 3 and 4, the various components are laid out in a flat and tiled manner, thereby lowering the center of gravity of the terminal, increasing the vibration resistance of the terminal, and reducing the optical path offset of the optical system caused by vibration.

[0066] Furthermore, in the optomechanical system 10 of the present invention, each component is built using discrete devices. The driving module of the laser (not shown in the figure) and the communication receiving unit 130 can be adapted to the transceiver optical system based on the physical structure of the laser pigtail and the photosensitive surface of the communication receiving unit 130, such as the APD detector. The consistency of the transceiver optical path is achieved through optical assembly and adjustment. Compared with the existing system based on polarized light to realize optical signal transmission, the system complexity is reduced and it is easier to implement.

[0067] Those skilled in the art will understand that the various exemplary modules and units described in connection with embodiments of the present invention can be implemented as hardware devices, and where feasible, some of them can be implemented in software form or a combination of both.

[0068] The foregoing description of this invention is intended to enable any person skilled in the art to make or use the invention. Various modifications to the invention will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the spirit and scope of the invention. Therefore, the invention is not limited to the examples and designs described herein, but is consistent with the broadest scope of the principles and novel features disclosed herein.

Claims

1. An optomechanical system for an inter-satellite laser communication terminal, comprising: An optical path unit, the optical path unit including a single pendulum mirror, the single pendulum mirror scanning the received light from another inter-satellite laser communication terminal in a first mode; as well as The tracking and aiming receiving unit determines the position of the light spot when it detects received light from the optical path unit. The optical path unit is further configured to, after determining the spot position of the received light, adjust the deflection direction of the pendulum mirror to guide the spot position to the center of the tracking and aiming receiving unit and scan the received light in a second mode, wherein the scanning angle of the second mode is smaller than that of the first mode, and the scanning frequency of the second mode is higher than that of the first mode. The optical path unit includes: The receiving optical path includes a single-pendulum mirror, a transceiver antenna mirror group, a dichroic mirror, a dual narrowband filter, and a beam splitter arranged sequentially according to the direction of travel of the received light. The transceiver antenna mirror assembly amplifies the received light from the single-pendulum mirror and transmits it to the dichroic mirror. The dichroic mirror transmits the received light and sends it into the dual narrowband filter. The dual narrowband filter transmits the received light and transmits the received light to the tracking and receiving unit via the beam splitter.

2. The optomechanical system of claim 1, wherein the tracking receiver unit comprises a four-quadrant avalanche photodiode detector.

3. The optomechanical system of claim 1, wherein the optomechanical system further comprises: A communication receiving unit, located downstream of the beam splitter, is used to receive the received light from the beam splitter.

4. The optomechanical system of claim 3, wherein the communication receiving unit includes an avalanche photodiode detector.

5. The optomechanical system of claim 3, wherein the optical path unit further comprises: A first reflector group is located between the beam splitter and the communication receiving unit, and is used to reflect the received light so that the direction of the received light enters the communication receiving unit perpendicularly.

6. The optomechanical system of claim 1, wherein the optical path unit further includes a transmitting optical path, the transmitting optical path being used to transmit transmitted light to the other inter-satellite laser communication terminal.

7. The optomechanical system of claim 6, wherein the emitting optical path comprises: The transmitting mirror group, fast-reflecting mirror, dichroic mirror, transceiver antenna mirror group, and single-pendulum mirror are arranged sequentially according to the direction of light travel. The transmitting mirror group transmits the emitted light emitted by the laser. The fast-reflecting mirror reflects the emitted light back to the dichroic mirror. The dichroic mirror reflects the emitted light. The transceiver antenna mirror group expands the emitted light reflected by the dichroic mirror and emits the expanded emitted light through the pendulum mirror.

8. The optomechanical system of claim 1, wherein the receiving optical path further comprises: The second reflector group, located between the transceiver antenna mirror group and the dichroic mirror, is used to reverse the received light in the receiving optical path.

9. The optomechanical system of claim 7, wherein the emitting optical path further comprises: The second reflector group, located between the transceiver antenna mirror group and the dichroic mirror, is used to reverse the emitted light in the emitted light path.

10. The optomechanical system of claim 7, further comprising: The advance aiming unit determines the advance control amount of the emitted light based on satellite broadcast data from the current satellite where the inter-satellite laser communication terminal is located and another satellite where the other inter-satellite laser communication terminal is located, so as to deflect the emitted light emitted by the laser in advance. The satellite broadcast data includes at least the coordinates and velocities of the current satellite and the other satellite.

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