Since the 21st century, Spatial laser communication has made a breakthrough development. Europe, the United States, Japan and other space powers have carried out the test of spatial laser communication technology on-orbit, and put forward a series of plans. In 2011, China made the first technology demonstration of satellite-ground laser communication carried by HY-2 satellite. Nowadays, in order to improve the transmission rate of spatial network, the topic of spatial laser communication network is becoming a research hotspot at home and abroad. This thesis, from the basic problem of spatial laser communication network to solve, analyzes the main difference between spatial network and ground network, which draws forth the key technology of spatial laser communication backbone network, and systematically introduces our research on aggregation, addressing, architecture of spatial network. From the perspective of technology development status and trends, the thesis proposes the development route of spatial laser communication network in stages. So as to provide reference about the development of spatial laser communication network in China.
Integrated optical transport network is the development trend of the future space information backbone network. The space and ground integrated optical transport network(SGIOTN) may contain a variety of equipment and systems. Changing the network or meeting some innovation missions in the network will be an expensive implement. Software Defined Network(SDN) provides a good solution to flexibly adding process logic, timely control states and resources of the whole network, as well as shielding the differences of heterogeneous equipment and so on. According to the characteristics of SGIOTN, we propose an transport SDN architecture for it, with hierarchical control plane and data plane composed of packet networks and optical transport networks.
Space broadband network based on laser link represents the future development direction, Europe, the United States, Japan and other space powers have been researching the theory of space laser communication and the key technology constantly, and have carried out the key technology test of inter-satellite laser communication and satellite-ground laser communication on orbit. However, what is the technology system of space broadband network based on laser link? up to now, it is still controversial, such as wavelength, coding, and modulation mode, exchange mode and so on. Here, by analyzing all kinds of space laser communication test and its technology parameters, combined with the application requirement of space broadband network, a set of technology system for space broadband network based on laser link is put forward, although just a preliminary research result. At first, this paper introduces the basic conception of space broadband network based on laser link, defines the space laser broadband network technology system and its research scope. Then analyze the main contents of space laser broadband network technology system, especially the technical route choice involved, and by studying, the related suggestions are given. Finally, with the development of space broadband network, the issue of standardization in space laser communication technology system is put forward, in order to cause attaches great importance to scientific research institutes and relevant experts.
The performance of satellite-to-ground laser communication is affected by the atmospheric environment seriously, so it is a key issue for system design and operation to analyze the link availability quantitatively according to the channel characteristics. Firstly, the basic concept of laser communication link availability is put forward. Secondly, the preliminary theory model and calculation method of geostationary satellite-to-ground laser communication link availability are established by analyzing influencing factors. Lastly, the link availability of 77°E GEO satellite-to-ground laser communication is analyzed, combining with the atmospheric statistics data of typical optical ground stations in China. The results show that, it is feasible to achieve more than 90% joint link availability by implementing two stations, or to achieve more than 95% joint link availability by implementing three stations.