基于SOPC的高精度时间间隔测量仪设计

Design and realization of a nanosecond time interval measurement instrument based on SOPC

针对靶场测试中时间间隔测量仪测量精度低、体积庞大的缺点,在SOPC技术的基础上,采用计数法和内插法设计了一种纳秒级的高分辨率大范围时间间隔测量仪.设计的仪器由触发信号隔离模块、纳秒计时模块、标准计数模块以及相应外围电路组成.在接收到起始触发信号后,由FPGA内部基于SOPC的主单片机和时序电路构成的标准计数模块开始计数.同时,TDC GP2芯片和基于SOPC的从单片机构成的纳秒计时模块测量起始触发脉冲和标准计时脉冲的时间间隔;截止触发信号到来后,标准计数模块停止计数,纳秒计时模块测量截止触发脉冲和标准计时脉冲间的时间间隔,测量结束后,主单片机计算并显示最终时间间隔值.设计的时间间隔测量仪测量范围可以达到1～4＆#215;105μs,测量精度优于3 ns.

（Objective）Because the low measurement accuracy and huge in size of time interval measurement instrument in modern weapon test, this paper designs a wide range of high-resolution nanosecond interval measuring instrument using the counting and interpolation which based on the SOPC technology. The designed instrument consists of trigger signal isolation module, nanosecond timing module, standard counting module and corresponding peripheral circuit. Alter re ceiving the starting trigger signal, the standard counting module which consist master MCU based on S（）PC and timing module start counting, which designed in FPGA. Meanwhile, Nanosecond timing module which include TDC-GP2 and slave MCU based on SOPC measure the time interval between the starting trigger signal and standard timing pulse; After receive the cut off trigger signal, the standard counting module stop to count, the nanosecond timing module measure the time interval between the cut off trigger signal and standard timing pulse. After the test finish, the master MCU count and display the time interval. The designed instrument can measure the time interval in 1-4×10^5 μs, the measure aecu racy is less than 3 ns.