High-speed space laser communication system composition

The high-speed space laser communication system has two optical paths between the two parties. Among them, the signal light is used to transmit the high-speed data beacon light for the APT system for alignment. The working process of the ultra-high-speed laser communication system is mainly divided into 4 steps: system warm-up, capture process, tracking and aiming process, and data transmission. Therefore, the high-speed space laser communication system also needs to input the initial position information of the communicating parties for acquisition and tracking. In practical applications, when the high-speed space laser communication system is used as an inter-satellite link, the main problem that needs to be overcome is that sunlight is the strong background radiation generated by the clouds, snow and ocean reflections on the earth's surface; it is used as a satellite-to-earth link At this time, the main problems that need to be overcome are serious attenuation caused by the laser passing through the atmosphere and the randomness of the atmospheric channel. When the high-speed space laser communication system is deployed in the aerospace information network, two important issues are: 　　1. Node movement All nodes in the aerospace information network are in regular high-speed motion (orbital motion), so the position of the node can be based on Initially applied optical Hu Hefei and other high-speed space laser communication systems to calculate the starting position and orbit information in the aerospace information network. Therefore, it is necessary to increase the ability to process orbit information in the APT subsystem.　　2, integration with networking load 　　The function of networking load is to control the link for networking, and it can also include data exchange and data routing. As the communication physical layer, the high-speed space laser communication system must be efficiently integrated with the networking load to form a complete protocol stack. 2. The application of high-speed space laser communication system in the aerospace information network 1. Working mechanism The nodes of the aerospace information network include space-based network nodes and space-based network nodes. There are many factors that determine the link deployed by the node, mainly platform capabilities, Node function, movement speed and orbital height, etc. According to the node type and link characteristics of the aerospace information network, the high-speed space laser communication system can be deployed on GEO orbital nodes, MEO orbital nodes and adjacent space nodes, mainly to provide high-speed data transmission on the same orbital plane between these relatively stable nodes.　　 The two nodes equipped with the high-speed space laser communication system need to be tracked and locked by the APT subsystem before the communication subsystem performs data transmission. Therefore, the network load needs to input the location information of the opposite node to the high-speed space laser communication system for use by the APT subsystem. The complete position information should include the three-dimensional position of the opposing node, node attitude, orbital parameters, etc.　　 A safe and reliable network connection must be established between the nodes of the Sky Information Network. Therefore, in addition to the location information that the APT sub-system needs to input, before the APT sub-system works, the nodes of the aerospace communication network must also establish a system-level trusted relationship with the other node, that is, the two communication nodes perform mutual security authentication to ensure that the other node Can be accessed safely. Therefore, before the network load starts the high-speed space laser communication system to work, it needs to consider using other communication links to exchange information. This information includes the identity information and location information of the opposite node, etc. The communication link that exchanges this information can be defined as a control link. Before the actual deployment, we do not need to specify the specific communication technology used for this control link, but some of the technical requirements for this control link are as follows: 　　 adopt an omnidirectional antenna and cover the largest possible area; 　　 no channel contention guarantee Control information transmission; 　　 provides the lower rate required for control information transmission.　　 The communication link that meets the above technical requirements can be considered as a control link, such as a tactical data link system. Therefore, the network nodes that use the high-speed space laser communication system in the aerospace information network are equipped with at least two types of communication loads, namely the high-speed space laser communication system load and a low-speed control link load. (The above metal laser cutting machine is edited and compiled from the Internet, see www.gnlaser.com for details)