地基大型望远镜数字通信系统的设计

Data communication system for large ground-based telescope design

数据通信系统是整个大型望远镜的数据传输中枢。针对地基大型望远镜分系统多,信号种类繁杂、分布不均匀和分布距离较远等特点,设计了一种基于大规模集成电路FPGA的数据通信系统。系统分为机上数据通信系统和机下数据通信系统两部分,机上与机下数据通信系统通过单根光纤进行连接。系统最多可提供60路RS422、32路TTL、10路RS485和4路RS232同步传输。同时,系统以GPS时钟频率为基准频率产生多种工作时序,为望远镜提供同步工作脉冲;通过采集曝光脉冲对应时刻的时间数据和编码器数据锁存当前的时空信息。硬件方面采用XILINX公司的Virtex-5系列FPGA为核心处理芯片完成该系统的设计,实验结果表明系统可满足大型望远镜数据通信的需求。

The communication system which was the point of large ground-based telescope was presented,for meeting partial systems′ large number, data classes′ variety, data transmitting long distance and data′s uneven distribution. The system was made up by up data communication system and the bottom one. By using FPGA, the maximal communication capability of system was promoted to transmit 60 paths of RS422, 32 paths of TLL, 10 paths of RS485 and 4 paths of RS232 in one time, while the connection between up and bottom system was single optical fiber. In addition, the telescope ′ s working clock was supported by GPS, and the real-time spatial and time information was given by catching exposure signal ′s time and encoder data. The XILINX′ s Virtex-5 FPGA was designed in the heart place. The experiment results indicate that the system is valuable for large ground-based telescope.