Research On Key Technologies Of Satellite IP Gateway

Along with rapidly developing of modern communication and computer techniques, computer networks and satellite communications networks have become an important part of modern communication technology. TCP/IP is one of the important protocols used to network data transmission, which has become a mainstream protocol in network applications. Satellite communication is playing an important role in wireless communication due to its advantages such as wide coverage, good broadcast capability and no restriction of geographical conditions, so that it has also become an important means of wireless Internet. However, the conventional TCP/IP is designed for ground netowrks, and the Automatic Repeat Requrest and Flow Control Algorithm in TCP/IP may be affected by satellite link transmission with long delay, high bit error rate and asymmetric channels, leading to serious waste of satellite channel resource.To solve this problem, this thesis proposes a modified IP protocol stack by means of IP gateway design. TCP is still used for the ground network, while a special transmission layer protocol is adopted for the satellite segment, the specific control mechanism of which is used to reduce the inherent characteristics of satellite channels, especially to reduce the the influence of propagation delay on TCP performance, so as to improve the performance of network transmission.Considering the current status of the existing satellite communications systems in China, the thesis presents a network protocol design scheme and the protocol conversion gateway method for the intra-station network transmission system, and endeavors to provide a reference for design and implementation of high-speed data transmission and data sharing for other satellite communications systems, and lay a foundation for the future in efficient, secure and reliable operation of satellite communications and data receiving systems.