Satellite optical communication system and method

Abstract

The application provides a satellite optical communication system and method, wherein the system comprises a data transmission satellite, and the data transmission satellite is provided with a hologram transceiver module, the hologram transceiver module 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 for realizing communication between the optical beam transmission internal link and other devices inside the data transmission satellite, the spatial light modulator is used for loading a phase hologram, and the received optical beam is subjected to beam splitting processing or / and beam combining processing through the phase hologram, and each optical beam after the beam splitting processing carries the same communication data, and the interactive direct connection satellite is a satellite directly interacting with the data transmission satellite to transmit data. The application can improve the efficiency of the data transmission satellite in transmitting communication data.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite communication, in particular to a satellite optical communication system and method. BACKGROUND

[0002] At present, the link between inter-satellite laser communication is still point-to-point network establishment. In the existing point-to-point communication method, if the intermediate link appears broken or data loss, it needs to be retransmitted through a complex process, including the receiving end sending an unsuccessful reception instruction, the sending end retransmitting the link establishment instruction, the receiving end retransmitting the link establishment confirmation instruction, and the process of retransmitting the data. This reduces the efficiency of satellite communication. SUMMARY

[0003] To solve the above problems, the present application provides a satellite optical communication system and method, which can realize beam splitting and beam combining by configuring a hologram transceiver module in the data transfer satellite, thereby improving the efficiency of data transfer satellite in transmitting communication data.

[0004] In a first aspect, the present application provides a satellite optical communication system, which comprises a data transfer satellite.

[0005] The data transfer satellite is configured with a hologram transceiver module, which comprises an optical input / output port, a spatial light modulator and an optical head.

[0006] The optical input / output port, the spatial light modulator and the optical head form an internal beam transmission link; the optical input / output port is used to realize communication between the internal beam transmission link and other devices inside the data transfer satellite.

[0007] 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 transfer satellite, and to perform beam splitting or / and beam combining on the received light beam through the phase hologram. Each beam after beam splitting carries the same communication data; the interactive direct connection satellite is a satellite that directly interacts with the data transfer satellite.

[0008] The optical head is used to emit the light beam split by the spatial light modulator to the interactive direct connection satellite in at least one direction, or / and receive the light beam sent by the interactive direct connection satellite.

[0009] Optionally, the hologram transceiver module further comprises a fast mirror.

[0010] The fast mirror is arranged between the optical input / output port and the spatial light modulator, and is used to adjust the deflection angle of the light beam transmitted between the optical input / output port and the spatial light modulator.

[0011] Optionally, the hologram transceiver module further comprises a controller.

[0012] The controller is connected with the fast reflecting mirror and the spatial light modulator, and is used for controlling the fast reflecting mirror to deflect the angle of the light beam and controlling the spatial light modulator to load the phase hologram.

[0013] Optionally, the other device comprises a data receiver.

[0014] The data receiver is connected with the hologram transceiver module through the optical input and output port, and is used for judging the quality of the communication data received by the hologram transceiver module, and saving the communication data with the best quality.

[0015] Optionally, the data transmission satellite is further configured with a timing module and a release module.

[0016] The release module is used for sending a link release signal to the satellite on the communication link, so that the satellite receiving the link release signal is adjusted to a standby mode; the communication link is a link formed by the satellite for transmitting the communication data.

[0017] The timing module is connected with the release module, and is used for starting timing when the data transmission satellite confirms the formation of the communication link, and triggering the release module when the timing exceeds a predetermined time length, so that the release module sends the link release signal.

[0018] Optionally, the data transmission satellite is further configured with an identification module.

[0019] The identification module is connected with the release module, and is used for identifying whether the signal received by the data transmission satellite is the link release signal, and triggering the release module to send the link release signal if yes.

[0020] In the second aspect, the present application provides a satellite optical communication method, which is applied to the satellite optical communication system as any one of the first aspect, and when the data transmission satellite in the satellite optical communication system is used as a data sending satellite, the method comprises:

[0021] The data sending satellite loads the phase hologram according to the number of the interactive direct connection satellites and the positions of the interactive direct connection satellites relative to the data sending satellite, and performs beam splitting processing on the light beam entering the internal link of the light beam transmission through the optical input and output port through the phase hologram.

[0022] Optionally, the interactive direct connection satellite comprises a downstream interactive direct connection satellite and an upstream interactive direct connection satellite; the downstream interactive direct connection satellite is an interactive direct connection satellite receiving the light beam carrying the communication data sent by the data sending satellite; the upstream interactive direct connection satellite is an interactive direct connection satellite sending the light beam carrying the communication data to the data sending satellite.

[0023] The data transmitting satellite loads the 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 transmitting satellite, and the step of loading the phase hologram comprises: the data transmitting satellite loads the 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 transmitting satellite.

[0024] The method further comprises:

[0025] The data transmitting satellite adjusts the angle of the light beams carrying communication data through the internal fast mirror according to the position of the downstream interactive direct connection satellites relative to the data transmitting satellite, so that each light beam carrying communication data can be transmitted to the corresponding downstream interactive direct connection satellite.

[0026] Optionally, the method further comprises:

[0027] The data transmitting satellite loads the 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 transmitting satellite.

[0028] The data transmitting satellite performs beam combining processing on the light beams entering the internal link of the light beam transmission through the optical head by using the incoming phase hologram.

[0029] Optionally, the method further comprises:

[0030] The data transmitting satellite determines whether the received signal is a link release signal, and if so, adjusts the working mode of the data transmitting satellite to the standby mode, and determines whether there is an upstream interactive direct connection satellite, and if so, forwards the link release signal to the upstream interactive direct connection satellite.

[0031] In a third aspect, the present application provides a satellite optical communication method, which is applied to the satellite optical communication system as claimed in any one of the first aspect, and when the data transmitting satellite in the satellite optical communication system is used as a data receiving satellite, the method comprises:

[0032] The data receiving satellite loads the 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 beams carrying communication data through the phase hologram.

[0033] The data receiving satellite performs data processing on the light beams after the beam combining processing to obtain the communication data carried in the light beams after the beam combining processing.

[0034] Optionally, the interactive direct connection satellites comprise upstream interactive direct connection satellites and downstream interactive direct connection satellites; the upstream interactive direct connection satellites are the interactive direct connection satellites transmitting the light beams carrying communication data to the data receiving satellite; and the downstream interactive direct connection satellites are the interactive direct connection satellites receiving the light beams carrying communication data transmitted by the data receiving satellite.

[0035] The data receiving satellite loads the phase hologram according to the number of the interactive direct connection satellites and the position information of the interactive direct connection satellites relative to the data receiving satellite, and the step of performing the beam combining processing on the received light beams carrying the communication data by the phase hologram comprises: the data receiving satellite loads the in-coupling phase hologram according to the number of the upstream interactive direct connection satellites and the position information of the upstream interactive direct connection satellites relative to the data receiving satellite, and performs the beam combining processing on the received light beams carrying the communication data by the in-coupling phase hologram.

[0036] Optionally, the method further comprises:

[0037] The data receiving satellite loads the out-coupling phase hologram according to the number of the downstream interactive direct connection satellites and the position information of the downstream interactive direct connection satellites relative to the data receiving satellite.

[0038] The data receiving satellite transmits the light beams carrying the communication data to the corresponding downstream interactive direct connection satellites by the out-coupling phase hologram and the optical head.

[0039] Optionally, the method further comprises:

[0040] The data receiving satellite starts timing when confirming the formation of the communication link, and sends a link release signal to the upstream interactive direct connection satellite when the timing exceeds a predetermined time length, so that the upstream interactive direct connection satellite adjusts to the standby mode when receiving the link release signal.

[0041] Optionally, the method further comprises:

[0042] The data receiving satellite judges whether there is an upstream interactive direct connection satellite when receiving the link release signal, and forwards the link release signal to the upstream interactive direct connection satellite if there is.

[0043] Optionally, the method further comprises:

[0044] The data receiving satellite judges the quality of the received communication data and saves the communication data with the best quality.

[0045] The satellite optical communication system and method provided by the embodiment of the application can perform the beam splitting processing and the beam combining processing by configuring the hologram transceiver module on the data transmitting satellite, so that the communication data can be forwarded by multiple relay satellites when one satellite needs to send the communication data to another satellite, thereby effectively avoiding the problem of affecting the efficiency of satellite communication due to the disconnection or data loss of a single communication link when the communication data is sent through the single communication link. Attached Figure Description

[0046] 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.

[0047] Figure 1 This is a schematic structural block diagram of a data transmission satellite according to an embodiment of this application;

[0048] Figure 2 A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application;

[0049] Figure 3 A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application;

[0050] Figure 4 A schematic diagram illustrating communication data transmission by multiple data transmission satellites according to an embodiment of this application;

[0051] Figure 5 This is a schematic diagram illustrating the communication data transmission of multiple data transmission satellites according to an embodiment of this application.

[0052] 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

[0053] 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.

[0054] 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.

[0055] As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. It will be further understood that the terms "comprises", "comprising", "includes" and / or "including", or the like, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

[0056] In a first aspect, an embodiment of the present application provides a satellite optical communication system, the system comprising: a data transmission satellite.

[0057] The data transmission satellite is configured with a hologram transceiver module. Figure 1 The hologram transceiver module 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.

[0058] It can be understood that the data transmission satellite can also be configured with an optoelectronic conversion module, and the optoelectronic conversion module is connected with the optical input-output port. When the data transmission satellite needs to send out communication data, the optoelectronic conversion module converts the communication data in the form of electrical signals into the communication data in the form of optical signals, that is, obtains an optical beam carrying communication data, and then inputs the optical beam into the optical beam transmission internal link through the optical input-output port, so as to emit the optical beam through the optical head.

[0059] When the data transmission satellite receives an optical beam carrying communication data sent from outside, the optical beam enters the optical beam transmission internal link through the optical head, and is transmitted to the optoelectronic conversion module through the optical input-output port, so as to convert the communication data carried in the optical beam into electrical signals, for processing of the electrical signals by other devices inside the data transmission satellite. The present embodiment does not limit the process of the optoelectronic conversion module and the processing of the electrical signals by other devices inside the data transmission satellite.

[0060] 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 beam 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.

[0061] The optical head is used to emit the optical beam split by the spatial light modulator to the interactive direct connection satellite along at least one direction, or / and to receive the optical beam sent by the interactive direct connection satellite. In the present embodiment, the optical head adopts a Cassegrain telescope structure, so that the optical beam passing through the optical head can be expanded and collimated.

[0062] It can be understood that for the data transfer satellite only having the function of transmitting communication data, the loaded phase hologram is only used for beam splitting processing of the light beam transmitted from the internal link of the light input and output port; for the data transfer satellite only having the function of receiving communication data, the loaded phase hologram is only used for beam combining processing of the light beam transmitted from the internal link of the optical head.

[0063] In addition, for the same phase hologram loaded by the data transfer satellite, the light beam received by the data transfer satellite can be combined, and the light beam transmitted by the data transfer satellite can also be combined, or the data transfer satellite needs to load corresponding phase holograms respectively when receiving and transmitting the light beam, one of which is responsible for receiving the light beam, and the other is responsible for transmitting the light beam. The specific needs are determined according to the number and position of the corresponding interactive direct connection satellite of the current data transfer satellite in the actual scene.

[0064] When the current satellite splits the light beam through the hologram transceiver module, it does not necessarily split the incident light beam into multiple light beams. When the number of interactive direct connection satellites corresponding to the current satellite for receiving data is one, the incident light beam actually does not need to be split by the hologram transceiver module of the current satellite, but only needs to control the deflection angle of the incident light beam to make the light beam emitted from the optical head can be transmitted to the corresponding interactive direct connection satellite.

[0065] In the embodiment, the data transfer satellite has the functions of light beam transmission and reception.

[0066] The satellite optical communication system provided in the embodiment can realize beam splitting and beam combining by configuring the hologram transceiver module on the data transfer satellite. When one satellite needs to send communication data to another satellite, the communication data can be forwarded by multiple relay satellites, thereby effectively avoiding the problem of affecting the efficiency of satellite communication due to the disconnection or data loss of a single communication link when communication data is transmitted through a single communication link. The communication link is a link formed by satellites for transmitting communication data. When one satellite needs to send communication data to multiple satellites, the communication data can be sent to multiple satellites at the same time, without the need to wait for the satellite to send communication data to multiple satellites in turn, thereby improving the efficiency of satellite communication.

[0067] Further, the optical input and output port can be used as an output port and an input port to realize the communication of the optical beam between the optical beam transmission internal link and other devices in the data transmission satellite. When used as an input port, the collimated optical beam carrying communication data after communication modulation can be output; when used as an output port, the optical beam carrying communication data can be received. The input port is used to receive the optical beam emitted by the optoelectronic conversion module, and the output port is used to emit the optical beam to the optoelectronic conversion module.

[0068] In addition to the communication with the external device through the optical beam, the data transmission satellite can also communicate with the external device through radio frequency signals. In the embodiment, a radio frequency communication module is also arranged in the data transmission satellite, and the data transmission satellite can communicate with the external device through the radio frequency communication module. Specifically, the data transmission satellite mainly transmits and receives a small amount of data such as control instructions and confirmation information with the external device through the radio frequency communication module. The data transmission satellite mainly transmits and receives a large amount of data with the external device through the hologram transceiver module.

[0069] For example, when satellite 1 needs to send communication data A with large capacity to satellite 2, the ground station will first send a communication instruction to each satellite on the communication link, and the communication instruction carries the communication link formed between satellite 1 and satellite 2, that is, the position and number of satellites that satellite 1 needs to use when transmitting communication data to satellite 2, so as to determine the transmission path of the communication data. After satellite 1 receives the communication instruction sent by the ground station, satellite 1 will capture and track each satellite on the communication link, and after capturing and tracking are completed, satellite 1 will send a confirmation information to satellite 2 through the radio frequency communication module, so that satellite 2 starts to receive the optical beam carrying the communication data sent by satellite 1 through the hologram transceiver module configured by itself within a predetermined time length after receiving the confirmation information, so as to complete the acquisition of the communication data.

[0070] In a further optional embodiment of the present embodiment, the hologram transceiver module further comprises a fast mirror. The fast mirror is arranged between the optical input and output port and the spatial light modulator, and is used to adjust the deflection angle of the optical beam transmitted between the optical input and output port and the spatial light modulator, so that the optical beam emitted from the optical head is directed to the corresponding interactive direct connection satellite.

[0071] It can be understood that when the fast mirror adjusts the deflection angle of the optical beam transmitted between the optical input and output port and the spatial light modulator, it will naturally also affect the phase hologram beam splitting result, so that the optical beam emitted from the optical head can be finally accurately transmitted to the corresponding interactive direct connection satellite.

[0072] In a further optional embodiment of the present embodiment, the hologram transceiver module further comprises a controller. The controller is connected with the fast mirror and the spatial light modulator, and is configured to control the fast mirror to deflect the light beam at a certain angle, and control the spatial light modulator to load the phase hologram.

[0073] It can be understood that the phase hologram can adjust the number of beam splitting and the angle of beam splitting when splitting the light beam, and cooperate with the fast mirror to realize the capture and tracking function of other satellites on the communication link.

[0074] It should be noted that when the controller controls the spatial light modulator to load the phase hologram, the controller mainly controls the liquid crystal molecules in the spatial light modulator to deflect by voltage according to the communication instruction, so as to realize phase control. In this way, the input phase hologram can be converted into voltage control of different pixels, so as to realize the functions of phase control and beam splitting or beam combining. In addition, after the light beam passes through the optical head of the current satellite and enters the spatial light modulator for coupling, that is, after the beam combining process, a corresponding light spot image will be generated on the camera in the current satellite. At this time, the host computer corresponding to the current satellite will control the fast mirror to perform fast and fine alignment through the controller of the current satellite, so that the light beam enters the light input and output port after coupling, and the hologram transceiver module of the current satellite is ejected.

[0075] The controller is a control board based on FPGA (Field-Programmable Gate Array), which is configured to receive and execute the communication instruction from the host computer, and the host computer includes but is not limited to a ground station. The interactive direct connection satellite includes a downstream interactive direct connection satellite and an upstream interactive direct connection satellite. 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 sending satellite. The upstream interactive direct connection satellite is an interactive direct connection satellite that sends the light beam carrying the communication data to the data sending satellite.

[0076] During the communication data sending stage of the current satellite, the controller on the current satellite receives the communication instruction sent by the host computer, and controls the fast mirror and the spatial light modulator through the program written in the FPGA according to the number of downstream interactive direct connection satellites and the position (deflection angle) relative to the current satellite, so as to load the phase hologram on the spatial light modulator and process the light beam incident from the light input and output port, so that the split light beams are respectively directed to each downstream interactive direct connection satellite.

[0077] During the data receiving stage of the current satellite, the controller on the current satellite receives the communication instruction sent by the host computer, and controls the spatial light modulator to load the phase hologram according to the number of upstream interactive direct connection satellites and the position relative to the current satellite, so that the received light beams are converged and combined after beam combining, and then ejected from the hologram transceiver module through the light input and output port, so that the current satellite obtains the communication data.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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 two sets of amplitude and period of the sinusoidal grating are optimized as variables by the simulated annealing algorithm. The simulated annealing algorithm will constantly update the variable values until the loss function meets the termination condition or reaches the maximum number of loops, thereby achieving optimization.

[0083] In the optimization process, , , and , The initial value is 0, the optimization mode is selected as the temperaturefast algorithm, the maximum number of loops is 4000, the termination condition is 1e-6, and the loss function is the normalized power value of the split beam , , The root mean square error RMSE of the set value , , . The temperaturefast algorithm is a commonly used algorithm in the simulated annealing algorithm, and the specific application of the temperaturefast algorithm in this embodiment will not be described.

[0084] In a further optional embodiment of the present embodiment, the other device includes a data receiver. The data receiver is in communication connection with the hologram transceiver module through the optical input and output port, and is used to judge the quality of the communication data received by the hologram transceiver module, and save the best communication data.

[0085] In this optional embodiment, the communication link established between the satellite of the data sending end and the satellite of the data receiving end is not less than two, so as to achieve the purpose of redundant communication. By judging the quality of the communication data, the repeated storage of the same communication data can be effectively avoided, and the waste of the data storage space in the current satellite is avoided. The quality of the communication data can be determined by judging the signal bit error rate corresponding to the communication data, and the lower the bit error rate, the higher the quality of the received communication data, which is not limited in the present embodiment.

[0086] In a further optional embodiment of the present embodiment, the data transfer satellite is also provided with a timing module and a release module.

[0087] The releasing module is configured to send a link releasing signal to the satellites on the communication link, so that the satellites receiving the link releasing signal are switched to a standby mode. It can be understood that the standby mode is a standby state. In the standby state, the satellite is powered on, but does not perform any substantial work (i.e., does not perform various operations on files and programs), and only the memory configured for the satellite is powered, while the hard disk, screen, CPU and other components are powered off. Meanwhile, for the satellites still in other data transmission stages, although the link releasing signal is received, the satellites need to wait until the data transmission is completed before being switched to the standby mode.

[0088] The timing module is connected to the releasing module, and is configured to start timing when the satellite confirms that the communication link is formed, and trigger the releasing module to send the link releasing signal when the timing exceeds a predetermined time length.

[0089] Generally, the satellite of the data receiving end, i.e., the target satellite, remains in a receiving state after the communication link is established, and receives all the communication data from the communication link. However, considering the case of link interruption, the target satellite sets a maximum waiting time according to the length of each communication link. When the time exceeds the maximum waiting time, the communication link that does not transmit the light beam carrying the communication data to the target satellite is regarded as an interrupted link due to signal loss. At this time, the target satellite sends a link releasing signal to the upstream interactive direct connection satellite on the communication link through the radio frequency communication module or / and the hologram transceiver module, so as to end the communication with the communication link, thereby effectively reducing the power consumption of the data transmission satellite.

[0090] In a further optional embodiment of the present embodiment, the data transmission satellite is further configured with an identifying module. The identifying module is connected to the releasing module, and is configured to identify whether the signal received by the data transmission satellite is a link releasing signal. If so, the releasing module is triggered to send the link releasing signal.

[0091] In the optional embodiment, the identifying module is mainly used when the current satellite is a relay satellite. In a further optional embodiment, the data transmission satellite is further configured with a judging module, which is configured to judge whether there is an upstream interactive direct connection satellite when the identifying module identifies the link releasing signal. If so, the releasing module is triggered to send the link releasing signal.

[0092] The satellite optical communication system provided by the present embodiment includes a plurality of data transmission satellites. The plurality of data transmission satellites can form a satellite optical communication system in which a data sending end satellite directly sends communication data to a plurality of data receiving end satellites, as shown in Figure 2 The plurality of data transmission satellites can also form a satellite optical communication system in which a plurality of data sending end satellites directly send communication data to a data receiving end satellite, as shown in Figure 3The plurality of data transmitting satellites can also form a satellite optical communication system in which a data sending end satellite sends communication data to a data receiving end satellite through a plurality of relay satellites as one or more groups of data forwarding stations. Figure 4 and Figure 5 It can be understood that the satellite optical communication system formed by the plurality of data transmitting satellites includes but is not limited to the above-mentioned several and combinations thereof.

[0093] The satellite optical communication system provided by the embodiment is based on a phase hologram, so that the increase in the number of access terminals is realized without increasing the optical head, and the proposed redundant communication scheme and one-to-many receiving scheme can also increase the flexibility and reliability of the satellite laser communication network, improve the communication capacity and communication efficiency.

[0094] In a second aspect, an embodiment of the present application provides a satellite optical communication method, which is applied to the satellite optical communication system in the first aspect, and when a data transmitting satellite in the satellite optical communication system is used as a data sending satellite, the method comprises the following steps of:

[0095] The data sending satellite loads a phase hologram according to the number of interactive direct connection satellites and the positions of the interactive direct connection satellites relative to the data sending satellite, and performs beam splitting processing on the light beam entering the light beam transmission internal link through the optical input and output port through the phase hologram.

[0096] It can be understood that the data sending satellite in the embodiment can be a data sending end satellite or a relay satellite. The difference is that for the data sending end satellite, there is only at least one downstream direct connection satellite, so the above-mentioned interactive direct connection satellite is the downstream direct connection satellite; for the relay satellite, there is at least one upstream direct connection satellite and at least one downstream direct connection satellite, so the above-mentioned interactive direct connection satellite is only the downstream direct connection satellite.

[0097] In a further optional embodiment of the embodiment, whether the data sending satellite is a data sending end satellite or a relay satellite, the step of loading a phase hologram by the data sending satellite according to the number of interactive direct connection satellites and the positions of the interactive direct connection satellites relative to the data sending satellite can be understood as: the data sending satellite loads an outgoing phase hologram according to the number of downstream interactive direct connection satellites and the positions of the downstream interactive direct connection satellites relative to the data sending satellite. The outgoing phase hologram is a phase hologram used for beam splitting processing on the light beam input into the spatial light modulator through the optical input and output port.

[0098] Similarly, no matter whether the data sending satellite is a data sending end satellite or a relay satellite, the method further comprises: the data sending satellite adjusting the angle of the light beam carrying the communication data by 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.

[0099] In a further optional embodiment of the present embodiment, when the data sending satellite is a relay satellite, the method further comprises:

[0100] The data sending satellite loads the in-coupling phase hologram according to the number of the upstream interactive direct connection satellites and the position information of the upstream interactive direct connection satellites relative to the data sending satellite; wherein the in-coupling phase hologram is a phase hologram for beam combining processing of the light beam input into the spatial light modulator through the optical head;

[0101] The data sending satellite performs beam combining processing on the light beam entering the light beam transmission internal link through the optical head by the in-coupling phase hologram.

[0102] It can be understood that the beam combining processing of the light beam through the in-coupling phase hologram is the reverse coupling of the light beam through the out-coupling phase hologram. Specifically, in the same data sending satellite, the relative upstream interactive direct connection satellite and the downstream interactive direct connection satellite are symmetrical, and the in-coupling phase hologram and the out-coupling phase hologram of the data sending satellite can be the same phase hologram. For example, in Figure 4 , if the data sending end satellite and the data receiving end satellite are symmetrical relative to the relay satellite 2, the in-coupling phase hologram and the out-coupling phase hologram configured in the relay satellite 2 are the same.

[0103] In particular, in Figure 4 , since the downstream interactive direct connection satellite corresponding to the data sending end satellite is the same as the upstream interactive direct connection satellite corresponding to the data receiving end satellite, the out-coupling phase hologram loaded in the data sending end satellite is the same as the in-coupling phase hologram loaded in the data receiving end satellite. Figure 4

[0104] In a further optional embodiment of the present embodiment, no matter whether the data sending satellite is a data sending end satellite or a relay satellite, the method further comprises:

[0105] The data sending satellite judges whether the received signal is a link release signal, if yes, the data sending satellite adjusts the working mode of itself to the standby mode, and judges whether there is an upstream interactive direct connection satellite, if yes, the data sending satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0106] ​In a third aspect, an embodiment of the present application provides a satellite optical communication method, which is applied to the satellite optical communication system as in the first aspect, and when a data receiving satellite in the satellite optical communication system is a data sending satellite, the method comprises the following steps of:

[0107] The data receiving satellite loads a phase hologram according to the number of interactive directly connected satellites and the positions of the interactive directly connected satellites relative to the data receiving satellite, and performs beam combining processing on the received optical beams carrying communication data through the phase hologram.

[0108] The data receiving satellite performs data processing on the beam after the beam combining processing to obtain the communication data carried in the beam after the beam combining processing.

[0109] In a further optional embodiment of the present embodiment, whether the data receiving satellite is a data sending satellite or a relay satellite, the step of the data receiving satellite loading a phase hologram according to the number of interactive directly connected satellites and the positions of the interactive directly connected satellites relative to the data receiving satellite, and performing beam combining processing on the received optical beams carrying communication data through the phase hologram can be understood as: the data receiving satellite loads an in-coupling phase hologram according to the number of upstream interactive directly connected satellites and the positions of the upstream interactive directly connected satellites relative to the data receiving satellite, and performs beam combining processing on the received optical beams carrying communication data through the in-coupling phase hologram; wherein the in-coupling phase hologram is a phase hologram for performing beam combining processing on the optical beams input into a spatial light modulator through an optical head.

[0110] When the data receiving satellite is a relay satellite, the method further comprises the following steps of:

[0111] The data receiving satellite loads an out-coupling phase hologram according to the number of downstream interactive directly connected satellites and the positions of the downstream interactive directly connected satellites relative to the data receiving satellite.

[0112] The data receiving satellite transmits the optical beams carrying communication data to corresponding downstream interactive directly connected satellites through the out-coupling phase hologram and an optical head.

[0113] In a further optional embodiment of the present embodiment, when the data receiving satellite is a data receiving end satellite, the method further comprises the following steps of:

[0114] The data receiving satellite starts timing when confirming formation of a communication link, and sends a link release signal to an upstream interactive directly connected satellite when the timing exceeds a predetermined time length, so that the upstream interactive directly connected satellite is adjusted to a standby mode when receiving the link release signal.

[0115] The step of the data receiving satellite confirming formation of a communication link comprises: confirming formation of a communication link when the data receiving satellite receives confirmation information.

[0116] In further optional embodiments of the present embodiments, when the data receiving satellite is a relay satellite, the method further comprises:

[0117] The data receiving satellite judges whether there is an upstream interactive direct connection satellite when receiving the link release signal, and if there is, the data receiving satellite forwards the link release signal to the upstream interactive direct connection satellite.

[0118] In further optional embodiments of the present embodiments, whether the data receiving satellite is a data sending end satellite or a relay satellite, the method further comprises:

[0119] The data receiving satellite judges the quality of the received communication data and saves the communication data with the best quality.

[0120] In the present embodiments, only the data sending end satellite judges the quality of the received communication data and saves the communication data with the best quality.

[0121] In the description of the present specification, the description of the terms "some embodiments", "other embodiments", "ideal embodiments", and the like means that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are contained in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0122] The technical features of the above embodiments can be combined in any manner. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combinations of the technical features do not contradict, they should be considered as the scope of the present application.

[0123] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A satellite optical communication system, characterized in that, The system includes: 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 spatial light modulator, and the optical head form an internal beam transmission link; the optical input / output port is used to enable communication between the internal beam transmission link and other internal devices of 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 the position information of the interactive direct-connect satellites relative to the data transmission satellite. The phase hologram is used to perform beam splitting and / or beam combining on the received light beam. Each beam after beam splitting carries the same communication data. The interactive direct-connect satellite is a satellite that directly interacts with the data transmission satellite. The optical head is used to transmit the beam split from the spatial light modulator to the interactive direct-connect satellite in at least one direction, and / or receive the beam transmitted by the interactive direct-connect satellite; The hologram transceiver module also includes: a fast-reflection mirror and a controller; The fast reflector is positioned between the optical input / output port and the spatial light modulator to adjust the deflection angle of the light beam propagating between the optical input / output port and the spatial light modulator; the controller is connected to the fast reflector and the spatial light modulator to control the angle at which the fast reflector deflects the light beam and to control the spatial light modulator to load the phase hologram.

2. The satellite optical communication system according to claim 1, characterized in that, The other devices include: a data receiver; The data receiver is communicatively connected to the hologram transceiver module through the 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.

3. The satellite optical communication system according to claim 1, characterized in that, 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 receiving the link release signal can switch to standby mode; the communication link is a link formed by satellites used to transmit the 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, and to trigger the release module when the timing exceeds a predetermined time, so that the release module sends the link release signal.

4. The satellite optical communication system according to claim 3, characterized in that, 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 the link release signal. If so, the release module is triggered to send the link release signal.

5. A satellite optical communication method, characterized in that, The method is applied to a satellite optical communication system as described in any one of claims 1 to 4; When the data transmission satellite in the satellite optical communication system acts as the data sending satellite, the method includes: The data transmitting satellite loads a phase hologram based on the number of interactive direct-connect satellites and the position of the interactive direct-connect satellites relative to the data transmitting satellite, and uses the phase hologram to perform beam splitting processing on the beams entering the internal link of the beam transmission through the optical input / output port.

6. The method according to claim 5, characterized in that, The interactive direct-connect satellites include: downstream interactive direct-connect satellites and upstream interactive direct-connect satellites; the downstream interactive direct-connect satellite is an interactive direct-connect satellite that receives a beam of light carrying the communication data sent by the data transmitting satellite; the upstream interactive direct-connect satellite is an interactive direct-connect satellite that sends a beam of light carrying the communication data to the 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 outward 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 further includes: The data transmitting satellite adjusts the angle of the beam carrying the 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 the communication data can be sent to the corresponding downstream interactive direct-connect satellite.

7. The method according to claim 6, characterized in that, The method further includes: the data transmitting satellite loading an in-situ 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 transmitting satellite uses the internal phase hologram to perform beam combining processing on the beams that enter the internal beam transmission link through the optical head.

8. The method according to claim 6, characterized in that, 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.

9. A satellite optical communication method, characterized in that, The method is applied to the satellite optical communication system as described in any one of claims 1 to 4. When the data transmission satellite in the satellite optical communication system acts as the data receiving satellite, the method includes: The data receiving satellite loads a phase hologram based on the number of directly connected interactive satellites and the position of the directly connected interactive satellites relative to the data receiving satellite, and uses the phase hologram to perform beam combining on the received light beam carrying communication data. The data receiving satellite performs data processing on the beam after beam combining to obtain the communication data carried in the beam after beam combining.

10. The method according to claim 9, characterized in that, The interactive direct-connect satellites include: an upstream interactive direct-connect satellite and a downstream interactive direct-connect satellite; the upstream interactive direct-connect satellite is an interactive direct-connect satellite that sends a beam of light carrying the communication data to the data receiving satellite; the downstream interactive direct-connect satellite is an interactive direct-connect satellite that receives the beam of light carrying the communication data sent by the data receiving satellite. The step of loading a phase hologram onto the data receiving satellite based on the number of directly connected upstream satellites and the position information of the directly connected upstream satellites relative to the data receiving satellite, and then performing beam combining processing on the received beam carrying communication data using the phase hologram, includes: the data receiving satellite loading an inward phase hologram based on the number of directly connected upstream satellites and the position information of the directly connected upstream 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.

11. The method according to claim 10, characterized in that, 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 the communication data to the corresponding downstream interactive direct-connect satellite through the external phase hologram and the optical head.

12. The method according to claim 10, characterized in that, The method further includes: The data receiving satellite starts timing when it confirms the establishment of the communication link, and when the timing exceeds a 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.

13. The method according to claim 12, characterized in that, The method further includes: When the data receiving satellite receives the link release signal, it determines whether there is an upstream interactive direct-connect satellite. If there is, the data receiving satellite forwards the link release signal to the upstream interactive direct-connect satellite.

14. The method according to claim 9, characterized in that, The method further includes: The data receiving satellite determines the quality of the received communication data and saves the communication data with the best quality.

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