Research On Inter-Satellite Link Network And Transport Protocols

Inter-satellite links have become the inevitable trend of the development direction of the navigation satellite constellation, and its network and data transmission technology is the key which determines whether the system can perform well. However related knowledge and standard of traditional ground network has been unable to meet the needs of the space network. In order to adapt to the demand of inter-satellite links data transmission, this paper study the theory and technology associated with its network and transmission protocol. Its contents and results has some directive effect to the navigation satellite constellation's building.The main research contents of this paper can be summarized as:1. The establishment of navigation constellation inter-satellite links network basic models. The basic models consist of basic demand models of the network, building a chain topology model and a transmission protocol model. Application of pattern specific content includes inter-satellite links network, topological analysis of attribute and visibility, the link cost analysis etc.2. Inter-satellite links time slot planning and design based on STDMA access mode network. This paper puts forward a kind of "8 fixed link +12 time-varying link" time slot planning scheme based on inter satellite visibility and other link property, and gives the planning adjustment scheme of satellite fault conditions. It can be well used within the data transmission mode of inter-satellite links.3. Design of data transmission protocol for navigation constellation information. This paper combines the traditional ground network TCP and space transmission protocol SCPS-TP, then designs the functions of the transport layer protocol and specially puts forward a kind of improved SNACK scheme-- reverse SNACK response mechanism, and then gives the transport layer protocol frame format and the data processing flow.4. Finally, in order to verify the rationality and feasibility of our design, a simulation experiment was carried out. We analysis performance built chain planning and network transmission under different conditions with different targets such as broadcast, unicast, delay, network throughput. We can find that the contents of the design is to meet the current navigation inter-satellite links' need.