摘要
提出一种改进的用时间放大技术来实现高精度时间测量的方法.即使用一个与对撞时刻严格同步的外时钟来标记输入信号的时刻,生成一个宽度介于一个到两个时钟周期的时间间隔;将标记后的时间间隔进行预设倍数的放大;再用一个具有多次击中能力的时间—数字转换(time-to-digital converter,TDC)芯片测量放大后的时间间隔,并结合物理的方法反推出输入信号到达的时刻.该方法由硬件实现,经验证明其能够获得好于25 ps的时间测量精度,可以满足北京谱仪三期(BESⅢ)改造工程的飞行时间(time of flight,TOF)测量电子学部分25ps的时间测量精度要求,也可应用到其他类似的高精度时间测量系统中.
An improved solution using a time interval expanding technique is presented. The input signal timing is tagged by a reference clock which is strictly synchronized with a beam collision time, making a time interval between one and two clock cycles. The tagged time interval is expanded predicted time and read out by a multihit TDC （time-to-digital converter） chip, then the original arrival time of signal can be calculated by the data together with other physical methods. It has been implemented in hardware and has proved able to achieve a precision better than 25 ps. It can meet the demand of a precision of 25 ps in the design of time-of-flight（TOF） front-end-electronics for Beijing spectrometer （BES Ⅲ）, and can also be used on other occasions needing high time measurement precision.
基金
中国科学技术大学校青年基金
