Satellite optical communication system and method

Abstract

The invention provides a satellite optical communication system and method. The system comprises a data transmission satellite; a hologram transceiving module is configured in the data transmission satellite and comprises a light input / output port, a spatial light modulator and an optical head; the light input / output port, the spatial light modulator and the optical head form a light beam transmission internal link; the optical input and output port is used for realizing communication between a light beam transmission internal link and other devices in the data transmission satellite; the spatial light modulator is used for loading a phase hologram, the received light beams are subjected to beam splitting processing or / and beam combining processing through the phase hologram, and the light beams after beam splitting processing carry the same communication data; and the interactive direct connection satellite is a satellite which directly performs data interaction with the data transmission satellite. According to the invention, the communication data transmission efficiency of the data transmission satellite can be improved.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a satellite optical communication system and method. Background Technology

[0002] Currently, inter-satellite laser communication links are still established through point-to-point networks. In existing point-to-point communication methods, if a link is broken or data is lost, a complex process of retransmission is required. This includes the receiver sending a failure to receive command, the sender retransmitting a link establishment command, the receiver retransmitting a link establishment confirmation command, and finally, data transmission restarts. This reduces the efficiency of satellite communication. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a satellite optical communication system and method that, by configuring a hologram transceiver module on a data transmission satellite, enables beam splitting and combining processes, thereby improving the efficiency of data transmission satellites in transmitting communication data.

[0004] In a first aspect, the present invention provides a satellite optical communication system, the system comprising: a data transmission satellite; The data transmission satellite is equipped with a hologram transceiver module, which includes: an optical input / output port, a spatial light modulator, and an optical head; The optical input / output port, the space light modulator, and the optical head form an internal link for beam transmission; the optical input / output port is used to enable communication between the internal beam transmission link and other devices inside the data transmission satellite. The space light modulator is used to load a phase hologram based on the number of interactive direct-connect satellites and their position relative to the data transmission satellite. The phase hologram is then used to split and / or combine the received light beams. Each split beam carries the same communication data. Interactive direct-connect satellites are satellites that directly interact with the data transmission satellite. The optical head is used to transmit a beam of light split from the space light modulator to an interactive direct link satellite in at least one direction, and / or to receive a beam of light transmitted by the interactive direct link satellite.

[0005] Optionally, the hologram transceiver module also includes: a fast-reflecting mirror; A fast-reflecting mirror is positioned between the optical input / output port and the spatial light modulator to adjust the deflection angle of the light beam as it travels between the optical input / output port and the spatial light modulator.

[0006] Optionally, the hologram transceiver module further includes: a controller; The controller is connected to the fast mirror and the spatial light modulator to control the angle at which the fast mirror deflects the beam and to control the spatial light modulator to load the phase hologram.

[0007] Optionally, other devices include: a data receiver; The data receiver communicates with the hologram transceiver module through the optical input / output port. It is used to determine the quality of the communication data received by the hologram transceiver module and to save the best quality communication data.

[0008] Optionally, the data transmission satellite is also equipped with a timing module and a release module; The release module is used to send a link release signal to the satellites on the communication link, so that the satellites that receive the link release signal can switch to standby mode; the communication link is a link formed by satellites used to transmit communication data; The timing module is connected to the release module and is used to start timing when the data transmission satellite confirms the establishment of the communication link. When the timing exceeds the predetermined duration, the release module is triggered to send a link release signal.

[0009] Optionally, the data transmission satellite is also equipped with an identification module; The identification module is connected to the release module and is used to identify whether the signal received by the data transmission satellite is a link release signal. If so, the release module is triggered to send a link release signal.

[0010] In a second aspect, the present invention provides a satellite optical communication method, which is applied to a satellite optical communication system as described in any of the first aspects, wherein when the data transmission satellite in the satellite optical communication system acts as a data transmitting satellite, the method includes: The data transmitting satellite loads a phase hologram based on the number of interactive direct-connect satellites and their relative positions to the data transmitting satellite. The phase hologram is then used to split the beams that enter the internal beam transmission link through the optical input / output ports.

[0011] Optionally, the interactive direct connection satellites include: downstream interactive direct connection satellites and upstream interactive direct connection satellites; the downstream interactive direct connection satellite is an interactive direct connection satellite that receives a beam of light carrying communication data sent by a data transmitting satellite; the upstream interactive direct connection satellite is an interactive direct connection satellite that sends a beam of light carrying communication data to a data transmitting satellite. The step of loading a phase hologram by the data transmitting satellite based on the number of directly connected satellites and the position information of the directly connected satellites relative to the data transmitting satellite includes: the data transmitting satellite loading an outgoing phase hologram based on the number of downstream directly connected satellites and the position information of the downstream directly connected satellites relative to the data transmitting satellite. The method also includes: The data transmitting satellite adjusts the angle of the beam carrying communication data by using an internal fast-reflecting mirror based on the position of the downstream interactive direct-connect satellite relative to the data transmitting satellite, so that each beam carrying communication data can be sent to the corresponding downstream interactive direct-connect satellite.

[0012] Optionally, the method further includes: The data transmitting satellite loads the internal phase hologram based on the number of upstream interactive direct-connect satellites and the position information of the upstream interactive direct-connect satellites relative to the data transmitting satellite; The data transmission satellite uses an internal phase hologram to combine the beams that enter the internal beam transmission link through the optical head.

[0013] Optionally, the method further includes: The data transmitting satellite determines whether the received signal is a link release signal. If so, the data transmitting satellite switches its operating mode to standby mode and determines whether there is an upstream interactive direct connection satellite. If so, the data transmitting satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0014] Thirdly, the present invention provides a satellite optical communication method, which is applied to a satellite optical communication system as described in any of the first aspects. When the data transmitting satellite in the satellite optical communication system acts as a data receiving satellite, the method includes: The data receiving satellite loads a phase hologram based on the number of directly connected satellites and the position of the directly connected satellites relative to the data receiving satellite. The phase hologram is then used to combine the received beams carrying communication data. The data receiving satellite processes the beam after it has been combined to obtain the communication data carried in the combined beam.

[0015] Optionally, the interactive direct connection satellites include: an upstream interactive direct connection satellite and a downstream interactive direct connection satellite; the upstream interactive direct connection satellite is an interactive direct connection satellite that sends a beam of light carrying communication data to a data receiving satellite; the downstream interactive direct connection satellite is an interactive direct connection satellite that receives a beam of light carrying communication data sent by a data receiving satellite. The steps of loading a phase hologram onto the data receiving satellite based on the number of directly connected satellites and the position information of the directly connected satellites relative to the data receiving satellite, and then performing beam combining processing on the received beam carrying communication data using the phase hologram, include: the data receiving satellite loading an inward phase hologram based on the number of upstream directly connected satellites and the position information of the upstream directly connected satellites relative to the data receiving satellite, and then performing beam combining processing on the received beam carrying communication data using the inward phase hologram.

[0016] Optionally, the method further includes: The data receiving satellite loads an outgoing phase hologram based on the number of downstream interactive direct-connect satellites and the position information of the downstream interactive direct-connect satellites relative to the data receiving satellite. The data receiving satellite transmits a beam of light carrying communication data to the corresponding downstream interactive direct-connect satellite via an external phase hologram and an optical head.

[0017] Optionally, the method further includes: The data receiving satellite starts timing when it confirms the establishment of the communication link, and when the timing exceeds the predetermined duration, it sends a link release signal to the upstream interactive direct-connect satellite, so that the upstream interactive direct-connect satellite switches to standby mode when it receives the link release signal.

[0018] Optionally, the method further includes: When the data receiving satellite receives the link release signal, it determines whether there is an upstream interactive direct connection satellite. If so, the data receiving satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0019] Optionally, the method further includes: The data receiving satellite determines the quality of the received communication data and saves the best quality communication data.

[0020] This invention provides a satellite optical communication system and method. By configuring a holographic transceiver module on the data transmission satellite, it enables beam splitting and combining. Thus, when one satellite needs to send communication data to another, multiple relay satellites can be used for data forwarding. This effectively avoids the efficiency problems caused by link breaks or data loss when sending communication data via a single link. Furthermore, when one satellite needs to send communication data to multiple satellites, it can send data to multiple satellites simultaneously without waiting for each satellite to send data sequentially, thereby improving the efficiency of satellite communication. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic structural block diagram of a data transmission satellite according to an embodiment of this application; Figure 2 A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application; Figure 3A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application; Figure 4 A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application; Figure 5 This is a schematic diagram illustrating the communication data transmission of multiple data transmission satellites according to an embodiment of this application.

[0023] Among them, Figure 1 The Z-shaped structure composed of black blocks in the middle represents the transmission path of the light beam within the hologram transceiver module; Figures 2 to 5 The arrow indicates the transmission direction of the beam carrying communication data between multiple data transmission satellites. Detailed Implementation

[0024] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0026] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0027] In a first aspect, one embodiment of the present invention provides a satellite optical communication system, the system comprising: a data transmission satellite.

[0028] The data transmission satellite is equipped with a holographic transceiver module. Combined with... Figure 1 The hologram transceiver module includes: optical input / output ports, a spatial light modulator, and an optical head. The optical input / output ports, spatial light modulator, and optical head form an internal beam transmission link. The optical input / output ports are used to enable communication between the internal beam transmission link and other devices within the data transmission satellite.

[0029] Understandably, data transmission satellites can also be equipped with photoelectric conversion modules, which are connected to optical input / output ports. When a data transmission satellite needs to transmit communication data, the photoelectric conversion module converts the communication data in electrical signal form into communication data in optical signal form, i.e., obtains a beam carrying the communication data. This beam is then input into the internal transmission link through the optical input / output port, so that it can be emitted out through the optical head.

[0030] When the data transmission satellite receives a beam of light carrying communication data sent from outside, the beam enters the beam transmission internal link through the optical head and is transmitted to the photoelectric conversion module through the optical input / output port to convert the communication data carried in the beam into an electrical signal for other devices inside the data transmission satellite to process. This embodiment does not limit the process of the photoelectric conversion module and other devices inside the data transmission satellite processing the electrical signal.

[0031] The space-based optical modulator is used to load a phase hologram based on the number of interactive direct-connect satellites and their position relative to the data transmission satellite. The received light beam is then split and / or combined using the phase hologram, with each split beam carrying the same communication data. Interactive direct-connect satellites are those that directly interact with the data transmission satellite.

[0032] The optical head is used to transmit a beam split from the space light modulator to an interactive direct-connect satellite along at least one direction, and / or receive a beam transmitted by the interactive direct-connect satellite. In this embodiment, the optical head adopts a Cassegrain telescope structure, enabling the beam passing through the optical head to be expanded, collimated, and output.

[0033] It is understandable that for data transmission satellites that only transmit communication data, the loaded phase hologram is only used to split the beams entering the beam transmission internal link from the optical input / output port; for data transmission satellites that only receive communication data, the loaded phase hologram is only used to combine the beams entering the beam transmission internal link from the optical head.

[0034] In addition, the same phase hologram loaded on the data transmission satellite can be used to combine the beams received by the data transmission satellite or the beams transmitted by the data transmission satellite. Alternatively, when the data transmission satellite is transmitting and receiving beams, it needs to load the corresponding phase holograms separately, one for receiving the beam and the other for transmitting the beam. The specifics need to be determined based on the number and location of the interactive direct-connect satellites corresponding to the current data transmission satellite in the actual scenario.

[0035] When the current satellite splits the light beam through its hologram transceiver module, it doesn't necessarily mean splitting the incident beam into multiple beams. If the current satellite has only one corresponding direct-connect satellite for receiving data, then the current satellite doesn't actually need to split the incident beam through its hologram transceiver module. Instead, it only needs to control the deflection angle of the incident beam to ensure that the beam emitted from the optical head can be transmitted to the corresponding direct-connect satellite.

[0036] In this embodiment, the data transmission satellite has the functions of beam transmission and reception.

[0037] The satellite optical communication system provided in this embodiment, by configuring a holographic transceiver module on the data transmission satellite, can perform beam splitting and beam combining. Thus, when one satellite needs to send communication data to another, multiple relay satellites can be used to forward the communication data. This effectively avoids the problem of reduced satellite communication efficiency caused by link breaks or data loss when sending communication data through a single communication link. Here, the communication link is the link formed by the satellites used to transmit communication data. When one satellite needs to send communication data to multiple satellites, it can send communication data to multiple satellites simultaneously, without waiting for satellites to send communication data to multiple satellites sequentially, thereby improving the efficiency of satellite communication.

[0038] Furthermore, the optical input / output ports can be used as both output and input ports to enable communication between the light beam and other devices within the data transmission satellite via the internal light beam transmission link. When used as an input port, it can output a collimated, communication-modulated light beam carrying communication data; when used as an output port, it can receive a light beam carrying communication data. The input port is used to receive the light beam emitted by the photoelectric conversion module, and the output port is used to transmit the light beam to the photoelectric conversion module.

[0039] In addition to communicating with external devices via light beams, data transmission satellites can also communicate with external devices via radio frequency (RF) signals. In this embodiment, the data transmission satellite is also equipped with an RF communication model, allowing it to communicate with external devices through an RF communication module. Specifically, the data transmission satellite primarily uses the RF communication module to send and receive small amounts of data with external devices, such as control commands and confirmation messages. The data transmission satellite also primarily uses a hologram transceiver module to send and receive large amounts of data with external devices.

[0040] For example, when Satellite 1 needs to send a large amount of communication data A to Satellite 2, the ground station first sends communication commands to each satellite on the communication link. These commands carry the information about the communication link between Satellite 1 and Satellite 2, specifying the location and number of satellites Satellite 1 needs to use to transmit data to Satellite 2, thus determining the data transmission path. After receiving the communication commands from the ground station, Satellite 1 acquires and tracks the satellites on each communication link. Upon completion of acquisition and tracking, Satellite 1 sends an acknowledgment message to Satellite 2 via its radio frequency communication module. Upon receiving the acknowledgment, Satellite 2, within a predetermined timeframe, begins receiving the beam of light carrying the communication data from Satellite 1 via its configured holographic transceiver module, thus acquiring the communication data.

[0041] In a further optional embodiment of this example, the hologram transceiver module further includes a fast-reflecting mirror. The fast-reflecting mirror is disposed between the optical input / output port and the spatial light modulator, and is used to adjust the deflection angle of the light beam propagating between the optical input / output port and the spatial light modulator, so that the light beam emitted from the optical head points to the corresponding interactive direct-connect satellite.

[0042] Understandably, when the fast-reflecting mirror adjusts the deflection angle of the beam as it propagates between the optical input / output port and the spatial light modulator, it will naturally affect the beam splitting result of the phase hologram, thus enabling the beam emitted from the optical head to be accurately transmitted to the corresponding interactive direct-connect satellite.

[0043] In a further optional embodiment of this example, the hologram transceiver module further includes a controller. The controller is connected to the fast-reflecting mirror and the spatial light modulator, and is used to control the angle of the fast-reflecting mirror deflecting the beam and to control the spatial light modulator to load the phase hologram.

[0044] Understandably, when splitting a beam, a phase hologram can adjust the number and angle of the split beams, and in conjunction with a fast-reflecting mirror, it can acquire and track other satellites on the communication link.

[0045] It should be noted that when the controller controls the spatial light modulator to load the phase hologram, it mainly uses voltage to control the deflection of liquid crystal molecules in the spatial light modulator according to communication commands, thereby achieving phase control. This converts the input phase hologram into voltage controls for different pixels, thus realizing phase control and beam splitting or combining functions. Furthermore, after the light beam enters the spatial light modulator through the current satellite's optical head and undergoes coupling (beam combining), a corresponding light spot image is generated on the camera of the current satellite. At this point, the host computer corresponding to the current satellite, through the current satellite's controller, controls the fast-reflecting mirror to perform rapid and precise alignment, so that the coupled light beam enters the optical input / output port to be emitted from the current satellite's hologram transceiver module.

[0046] The controller is an FPGA (Field-Programmable Gate Array) based control board used to receive and execute communication commands from a host computer, which includes, but is not limited to, a ground station. Interactive direct-connect satellites include downstream and upstream interactive direct-connect satellites; downstream interactive direct-connect satellites receive beams carrying communication data transmitted by data-transmitting satellites; upstream interactive direct-connect satellites transmit beams carrying communication data to data-transmitting satellites.

[0047] During the current satellite's data transmission phase, the controller on the current satellite receives communication instructions from the host computer. Based on the number of downstream interactive satellites and their relative positions (deflection angles) relative to the current satellite, the controller controls the fast reflector and space light modulator via a program written into the FPGA. The phase hologram loaded on the space light modulator processes the light beams incident from the optical input and output ports, so that the split beams are directed to each of the downstream interactive satellites.

[0048] During the data reception phase, the satellite receives communication commands sent by the host computer. Based on the number of upstream directly connected satellites and their relative positions, the host computer controls the space light modulator to load a phase hologram, causing the received light beams to converge. After beaming, the hologram transceiver module outputs the beam through the optical input / output port, enabling the satellite to acquire communication data.

[0049] It is understandable that when the current satellite is a relay satellite, after receiving the light beam emitted by its own hologram transceiver module, it can directly forward the light beam through the hologram transceiver module, or it can first optimize the light beam, such as through noise reduction or signal enhancement, before forwarding it. This embodiment does not make specific limitations on this.

[0050] In this embodiment, the phase hologram loaded by the spatial light modulator is derived from a phase hologram stored in the FPGA program. Its generation method is based on the phase function of a binary grating hologram. And on this basis, in the original phase function Superimposed sinusoidal grating phase function This is used to adjust the energy of different diffraction orders, and the simulated annealing algorithm is used for optimization until the light field distribution meets expectations.

[0051] Specifically, the phase function of a binary grating hologram ,in, It corresponds to the period of the binary grating, which is determined by the angle between the current data transmission satellite and the upstream or downstream interactive direct-connect satellite. Decide, , Let be the coordinates of the spatial light modulator plane, which is the plane in which the liquid crystal molecules are located in the spatial light modulator.

[0052] It is understandable that when the current data transmission satellite is transmitting communication data with the upstream directly connected satellite, that is, when the current data transmission satellite receives a beam of light carrying communication data emitted by the upstream directly connected satellite, The angle between the current data transmission satellite and the upstream interactive direct connection satellite Decision: If the current data transmission satellite is transmitting communication data with the downstream interactive direct-connect satellite, that is, when the current data transmission satellite transmits a beam of light carrying communication data to the upstream interactive direct-connect satellite, The angle between the current data transmission satellite and the downstream interactive direct connection satellite Decision. This embodiment addresses the included angle. The specific method for determining this is not limited.

[0053] The phase function of a sinusoidal grating achieves amplification or suppression of different diffraction orders by generating a Bessel series distribution in the optical field. Its functional form is: ,in, , ,as well as , The amplitude and period of the sinusoidal grating are used as variables for optimization using a simulated annealing algorithm. The simulated annealing algorithm continuously updates the variable values ​​until the loss function meets the termination condition or reaches the maximum number of iterations, thus achieving optimization.

[0054] During the optimization process, , ,as well as , The initial values ​​are all 0. The optimization method selected is the temperaturefast algorithm, the maximum number of iterations is 4000, the termination condition is 1e-6, and the loss function is the normalized power value of the split beam. , , With set value , , The root mean square error (RMSE) The temperaturefast algorithm is a commonly used algorithm in simulated annealing. This embodiment will not elaborate on the specific application of the temperaturefast algorithm.

[0055] In a further optional embodiment of this example, other devices include a data receiver. The data receiver is communicatively connected to the hologram transceiver module via an optical input / output port, and is used to determine the quality of the communication data received by the hologram transceiver module and save the communication data with the best quality.

[0056] In this optional embodiment, at least two communication links are established between the data transmitting satellite and the data receiving satellite to achieve redundant communication. By judging the quality of the communication data, the duplicate storage of the same communication data can be effectively avoided, thus preventing the waste of data storage space in the current satellite. The quality of the communication data can be determined by judging the bit error rate of the corresponding signal; a lower bit error rate indicates higher quality received communication data. This embodiment does not specifically limit this.

[0057] In a further optional embodiment of this example, the data transmission satellite is also equipped with a timing module and a release module.

[0058] The release module is used to send a link release signal to the satellites on the communication link, causing the satellites that receive the link release signal to enter standby mode. Standby mode is essentially a standby state. In standby mode, a satellite is powered on but does not perform any substantive work (i.e., it does not perform any operations on files or programs). The satellite only supplies power to its configured memory, while components such as the hard drive, screen, and CPU are not powered. Furthermore, for satellites still in other data transmission / reception phases, even if they receive the link release signal, they must wait until the satellite completes its data transmission / reception before entering standby mode.

[0059] The timing module is connected to the release module and is used to start timing when the data transmission satellite confirms the establishment of the communication link. When the timing exceeds the predetermined duration, the release module is triggered to send a link release signal.

[0060] Normally, the data receiving satellite, i.e., the target satellite, will remain in a receiving state after the communication link is established until it receives communication data from all communication links. However, considering the possibility of link interruptions, the target satellite sets a maximum waiting time based on the length of each communication link. If this time limit is exceeded, any communication link that has not transmitted a beam carrying communication data to the target satellite is considered an interrupted link due to signal loss. At this time, the target satellite sends a link release signal to the upstream interactive direct-connected satellite on that communication link through its radio frequency communication module and / or holographic transceiver module to terminate communication with that communication link, thereby effectively reducing the power consumption of the data transmission satellite.

[0061] In a further optional embodiment of this example, the data transmission satellite is also equipped with an identification module. The identification module is connected to the release module and is used to identify whether the signal received by the data transmission satellite is a link release signal. If so, it triggers the release module to send a link release signal.

[0062] In this optional embodiment, the identification module is primarily used when the current satellite is acting as a relay satellite. In a further optional embodiment, the data transmission satellite is also equipped with a judgment module, used to determine whether there is an upstream interactive direct connection satellite when the identification module identifies a link release signal; if so, it triggers the release module to send a link release signal.

[0063] The satellite optical communication system provided in this embodiment includes multiple data transmission satellites. These multiple data transmission satellites can form a satellite optical communication system in which a data transmitting satellite directly sends communication data to multiple data receiving satellites, such as... Figure 2 Multiple data transmission satellites can also form a satellite optical communication system in which multiple data transmitting satellites directly send communication data to a single data receiving satellite, such as... Figure 3 Multiple data transmission satellites can also form a satellite optical communication system where a data transmitting satellite sends communication data to a data receiving satellite via multiple relay satellites acting as one or more data forwarding stations. Figure 4 and Figure 5 It is understandable that satellite optical communication systems formed by multiple data transmission satellites include, but are not limited to, the above-mentioned types and combinations thereof.

[0064] The satellite optical communication system provided in this embodiment is based on phase holograms, which enables the number of access terminals to be increased without adding optical heads. At the same time, the proposed redundant communication scheme and one-to-many receiving scheme can also increase the flexibility and reliability of the satellite laser communication network, and improve communication capacity and efficiency.

[0065] In a second aspect, one embodiment of the present invention provides a satellite optical communication method, which is applied to the satellite optical communication system of the first aspect. When the data transmission satellite in the satellite optical communication system acts as a data transmitting satellite, the method includes: The data transmitting satellite loads a phase hologram based on the number of interactive direct-connect satellites and their relative positions to the data transmitting satellite. The phase hologram is then used to split the beams that enter the internal beam transmission link through the optical input / output ports.

[0066] It is understood that the data transmitting satellite in this embodiment can be either a data transmitting satellite or a relay satellite. The difference is that for a data transmitting satellite, there is only at least one downstream directly connected satellite; therefore, the aforementioned interactive directly connected satellite is a downstream directly connected satellite. For a relay satellite, there is at least one upstream directly connected satellite and at least one downstream directly connected satellite; therefore, the aforementioned interactive directly connected satellite is only a downstream directly connected satellite.

[0067] In a further optional embodiment of this example, regardless of whether the data transmitting satellite is a data transmitting end satellite or a relay satellite, the step of the data transmitting satellite loading a phase hologram based on the number of directly connected satellites and the position information of the directly connected satellites relative to the data transmitting satellite can be understood as: the data transmitting satellite loading an externally transmitted phase hologram based on the number of downstream directly connected satellites and the position information of the downstream directly connected satellites relative to the data transmitting satellite. The externally transmitted phase hologram is a phase hologram used for beam splitting of the light beam input to the spatial light modulator through the optical input / output port.

[0068] Similarly, regardless of whether the data transmitting satellite is a data transmitting satellite or a relay satellite, the method also includes: the data transmitting satellite adjusting the angle of the beam carrying communication data by using an internal fast-reflecting mirror according to the position of the downstream interactive direct-connect satellite relative to the data transmitting satellite, so that each beam carrying communication data can be sent to the corresponding downstream interactive direct-connect satellite.

[0069] In a further optional embodiment of this example, when the data transmitting satellite is a relay satellite, the method further includes: The data transmitting satellite loads an inward phase hologram based on the number of upstream interactive direct-connect satellites and the position information of the upstream interactive direct-connect satellites relative to the data transmitting satellite; the inward phase hologram is a phase hologram used to combine the beams input to the space light modulator through the optical head; The data transmission satellite uses an internal phase hologram to combine the beams that enter the internal beam transmission link through the optical head.

[0070] It is understandable that the beam combining through the inward-facing phase hologram is equivalent to the beam being reverse-coupled through the outward-facing phase hologram. Specifically, within the same data transmission satellite, if its upstream and downstream interactive direct-connected satellites are symmetrical, then the inward-facing and outward-facing phase holograms of that data transmission satellite can be the same phase hologram. For example, in... Figure 4 If the data transmitting satellite and the data receiving satellite are symmetrical with respect to relay satellite 2, then the internal receiving phase hologram and the external transmitting phase hologram configured in relay satellite 2 are the same.

[0071] In particular, Figure 4 In this context, because the downstream interactive direct-connect satellite corresponding to the data transmitting satellite is the same as the upstream interactive direct-connect satellite corresponding to the data receiving satellite, therefore... Figure 4 The outward phase hologram loaded in the data transmitting satellite is the same as the inward phase hologram loaded in the data receiving satellite.

[0072] In a further optional embodiment of this example, regardless of whether the data transmitting satellite is a data transmitting satellite or a relay satellite, the method further includes: The data transmitting satellite determines whether the received signal is a link release signal. If so, the data transmitting satellite switches its operating mode to standby mode and determines whether there is an upstream interactive direct connection satellite. If so, the data transmitting satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0073] Thirdly, one embodiment of the present invention provides a satellite optical communication method, which is applied to a satellite optical communication system as described in the first aspect. When the data transmitting satellite in the satellite optical communication system acts as a data receiving satellite, the method includes: The data receiving satellite loads a phase hologram based on the number of directly connected satellites and the position of the directly connected satellites relative to the data receiving satellite. The phase hologram is then used to combine the received beams carrying communication data. The data receiving satellite processes the beam after it has been combined to obtain the communication data carried in the combined beam.

[0074] In a further optional embodiment of this example, regardless of whether the data receiving satellite is a data transmitting satellite or a relay satellite, the step of loading a phase hologram based on the number of directly connected satellites and the position information of the directly connected satellites relative to the data receiving satellite, and then performing beam combining processing on the received beam carrying communication data using the phase hologram, can be understood as follows: the data receiving satellite loads an inward-facing phase hologram based on the number of upstream directly connected satellites and the position information of the upstream directly connected satellites relative to the data receiving satellite, and then performs beam combining processing on the received beam carrying communication data using the inward-facing phase hologram; wherein, the inward-facing phase hologram is a phase hologram used to perform beam combining processing on the beam input to the spatial light modulator through the optical head.

[0075] When the data receiving satellite is a relay satellite, the method also includes: The data receiving satellite loads an outgoing phase hologram based on the number of downstream interactive direct-connect satellites and the position information of the downstream interactive direct-connect satellites relative to the data receiving satellite. The data receiving satellite transmits a beam of light carrying communication data to the corresponding downstream interactive direct-connect satellite via an external phase hologram and an optical head.

[0076] In a further optional embodiment of this example, when the data receiving satellite is a data receiving end satellite, the method further includes: The data receiving satellite starts timing when it confirms the establishment of the communication link, and when the timing exceeds the predetermined duration, it sends a link release signal to the upstream interactive direct-connect satellite, so that the upstream interactive direct-connect satellite switches to standby mode when it receives the link release signal.

[0077] The steps for the data receiving satellite to confirm the formation of the communication link include: when the data receiving satellite receives the confirmation information, it confirms that the communication link has been formed.

[0078] In a further optional embodiment of this example, when the data receiving satellite is a relay satellite, the method further includes: When the data receiving satellite receives the link release signal, it determines whether there is an upstream interactive direct connection satellite. If so, the data receiving satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0079] In a further optional embodiment of this example, regardless of whether the data receiving satellite is a data transmitting satellite or a relay satellite, the method further includes: The data receiving satellite determines the quality of the received communication data and saves the best quality communication data.

[0080] In this embodiment, only the data transmitting satellite determines the quality of the received communication data and saves the communication data with the best quality.

[0081] In the description of this specification, the references to terms such as "some embodiments," "other embodiments," "ideal embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example that are included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0082] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A satellite optical communication system, characterized by, The system comprises a data transmission satellite; The data transmission satellite is provided with a hologram transceiver module, which comprises an optical input / output port, a spatial light modulator and an optical head; The optical input / output port, the spatial light modulator and the optical head form an optical beam transmission internal link; the optical input / output port is used to realize communication between the optical beam transmission internal link and other devices inside the data transmission satellite; The spatial light modulator is used to load a phase hologram according to the number of interactive direct connection satellites and the position information of the interactive direct connection satellites relative to the data transmission satellite, and to perform beam splitting processing or / and beam combining processing on the received optical beams through the phase hologram; each optical beam after the beam splitting processing carries the same communication data; the interactive direct connection satellite is a satellite that directly interacts with the data transmission satellite; The optical head is used to emit the optical beams split by the spatial light modulator to the interactive direct connection satellites in at least one direction, or / and receive the optical beams sent by the interactive direct connection satellites; The data transmission satellite is further provided with a timing module and a release module; The release module is used to send a link release signal to the satellites on the communication link, so that the satellites receiving the link release signal are switched to standby mode; the communication link is a link formed by the satellites for transmitting the communication data; The timing module is connected with the release module and is used to start timing when the data transmission satellite confirms the formation of the communication link, and trigger the release module when the timing exceeds a predetermined time length, so that the release module sends the link release signal.

2. The satellite optical communication system of claim 1, wherein, The other devices comprise a data receiver; The data receiver is in communication connection with the hologram transceiver module through the optical input / output port, and is used to judge the quality of the communication data received by the hologram transceiver module, and save the communication data with the best quality.

3. The satellite optical communication system of claim 1, wherein, The data transmission satellite is further provided with an identification module; The identification module is connected with the release module and is used to identify whether the signal received by the data transmission satellite is the link release signal, and trigger the release module to send the link release signal if yes.

4. A method of satellite optical communication, characterized by, The method is applied to the satellite optical communication system as claimed in any one of claims 1 to 3, and when the data transmission satellite in the satellite optical communication system is used as a data sending satellite, the method comprises: The data sending satellite loads a phase hologram according to the number of interactive direct connection satellites and the position of the interactive direct connection satellites relative to the data sending satellite, and performs beam splitting processing on the optical beams entering the optical beam transmission internal link through the optical input / output port through the phase hologram.

5. The method of claim 4, wherein, The interactive direct connection satellites comprise downstream interactive direct connection satellites and upstream interactive direct connection satellites; the downstream interactive direct connection satellite is an interactive direct connection satellite that receives the optical beams carrying the communication data sent by the data sending satellite; the upstream interactive direct connection satellite is an interactive direct connection satellite that sends the optical beams carrying the communication data to the data sending satellite; The data sending satellite loads a phase hologram according to the number of interactive direct connection satellites and the position information of the interactive direct connection satellites relative to the data sending satellite, and the step of loading the phase hologram comprises: the data sending satellite loads an outgoing phase hologram according to the number of downstream interactive direct connection satellites and the position information of the downstream interactive direct connection satellites relative to the data sending satellite. The method further comprises: The data sending satellite adjusts the angle of the light beam carrying the communication data through the internal fast mirror according to the position of the downstream interactive direct connection satellite relative to the data sending satellite, so that each light beam carrying the communication data can be sent to the corresponding downstream interactive direct connection satellite.

6. The method of claim 5, wherein, The method further comprises: The data sending satellite determines whether the received signal is a link release signal, and if so, adjusts the working mode of the data sending satellite to a standby mode, and determines whether the upstream interactive direct connection satellite exists, and if so, forwards the link release signal to the upstream interactive direct connection satellite.

7. A method of satellite optical communication, characterized by, The method is applied to the satellite optical communication system as claimed in any one of claims 1 to 3, and when the data transmission satellite in the satellite optical communication system is used as a data receiving satellite, the method comprises: The data receiving satellite loads a phase hologram according to the number of interactive direct connection satellites and the position of the interactive direct connection satellites relative to the data receiving satellite, and performs beam combining processing on the received light beam carrying the communication data through the phase hologram. The data receiving satellite performs data processing on the light beam after the beam combining processing to obtain the communication data carried in the light beam after the beam combining processing.

8. The method of claim 7, wherein, The interactive direct connection satellite comprises an upstream interactive direct connection satellite and a downstream interactive direct connection satellite; the upstream interactive direct connection satellite is an interactive direct connection satellite that sends a light beam carrying the communication data to the data receiving satellite; and the downstream interactive direct connection satellite is an interactive direct connection satellite that receives the light beam carrying the communication data sent by the data receiving satellite. The data receiving satellite loads a phase hologram according to the number of interactive direct connection satellites and the position information of the interactive direct connection satellites relative to the data receiving satellite, and performs beam combining processing on the received light beam carrying the communication data through the phase hologram, and the step of loading the phase hologram comprises: the data receiving satellite loads an incoming phase hologram according to the number of upstream interactive direct connection satellites and the position information of the upstream interactive direct connection satellites relative to the data receiving satellite, and performs beam combining processing on the received light beam carrying the communication data through the incoming phase hologram.

9. The method of claim 8, wherein, The method further comprises: The data receiving satellite loads an outgoing phase hologram according to the number of downstream interactive direct connection satellites and the position information of the downstream interactive direct connection satellites relative to the data receiving satellite. The data receiving satellite transmits the light beam carrying the communication data to the corresponding downstream interactive direct connection satellite through the outgoing phase hologram and the optical head.

10. The method of claim 8, wherein, The method further comprises: The data receiving satellite starts timing when the communication link is confirmed to be formed, and sends a link release signal to the upstream interactive direct satellite when the timing exceeds a predetermined time length, so that the upstream interactive direct satellite is adjusted to a standby mode when the link release signal is received.

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