Design And Implementation Of Key Modules In The Middle Stage And Output Stage Of Multi-stage Switching Fabric

With the development of aerospace technology, space communication systems are playing an increasingly important role, and their performance requirements have become more and more sophisticated, it is necessary to design new high-performance switching fabric which meets the application requirements of space communication.Switched Ethernet technology is a popular kind of LAN technology at home and abroad, it has received a wide range of applications, this technology is very mature and has broad prospects for development. Space Station works in the special environment with a large number of particles, so we can not use high-capacity single-chip FPGA to implement switching fabric, we must design our own small-capacity switching unit with small-capacity FPGA, and then implement high-capacity multi-stage switching fabric with small-capacity switching unit. So this dissertation presents a new design based on gigabit switched Ethernet technology and with the main structure of three-stage Clos switching fabric in MSM(Memory-Space-Memory) mode, this design, based on the laboratory research project "Research on Network Switching Technology in Space Station Information System", has the advantages of switched Ethernet, can fully meet the performance requirements of switching fabric for space communication.Firstly, a brief introduction of switched Ethernet technology and a brief analysis and comparison of different network structures is given in this paper. Secondlly, a need analysis of network switching technology in space station information system is made, and the overall framework of switching fabric and specific functions of switching unit in each stage are given. Thirdly, the design of key modules in the middle stage and output stage and the specific implementations are described. Finally, the key modules designed in this paper are timing simulated by Modelsim and board-level tests of these modules are done, actual test results show that the modules designed are correct and stable, and multi-stage switching fabric has proper design and reliable performance, the desired research target is finally achieved.