Design And Implementation Of Communication Protocol Of Amateur Radio Space Station

As a fascinating technology diffusion sport, Amateur Radio Sport still has its effect in technology education and disaster relief. When the communication system is destroyed by earthquake or some other natural hazards, the communication between disaster area and non-disaster area becomes very important. Additionally, the amateur radio sport is not only a high technical sport which combines electronic, English, computer, even astronomy, geography,etc, but also full of interests, especially for youngsters, it improves their practical and thinking skills for contributing their bests when grow up.For better spreading amateur packet radio sport and integrating with global community, supplying better message forward services for amateur radio funs and developing our own amateur radio space station is very important. The amateur radio space station must keep consist with AX.25 link access protocol for amateur packet radio in order to keep compatible with existing stations, and also it must have the features of real-time, reliable, low power and etc. In a word,reasonable usage of the limit resources, choosing a suitable operation system and implementation of the AX.25 protocol are the keys to develop an amateur radio space station.The main topic of this paper is around the design and implementation of communication protocol of amateur radio space station. According to developing concept of protocol engineering and taking consider of limit resources of embedded system, this paper focuses on how to implement the efficient AX.25 protocol base on comprehensive analysis of AX.25 protocol. Firstly, the basics of AX.25 protocol are introduced, including protocol model, frame structure and protocol flow. Secondly, the design of the system architecture and the system demands are introduced. Thirdly, the implementation methods of the data linker module and management data linker module of AX.25 protocol in embedded environment are described, and the implementation of the HDLC interface driver is briefly introduced. At the last of this paper, this subject is summarized and some ways for improvement are proposed.