设计了一种新的时钟插入技术以实现高分辨率的时间间隔测量仪。该时钟插入技术利用信号在传输时会有稳定的,规律的延迟特点,用一段传输线对时钟信号延迟,在传输线上根据设计分辨率的大小设置一些离散的检测点,用D触发器完成对延迟后的时钟信号与被测时间间隔开始或者结束信号的重合检测,根据重合点出现的位置推算出时钟信号与被测时间间隔开始或者结束信号的时差大小。采用FPGA芯片EP2C5Q204和上述时钟插入技术实现了一个高精度时间间隔测量仪。实验结果表明基于传输延迟的时钟插入技术具有分辨率高,温度稳定性高,抗干扰能力强,容易制造的特点。实现的时间间隔测量仪具有实现简单,稳定性好等优点。
A novel clock interpolation technology is proposed by utilizing the characteristics such as stabilization and regularity of the transmission delay to improve the measurement precision of a Time Interval Measurement Module (TIMM). A length of transmission line is used to delay the clock signal of the TIMM. Many detection points are set along the transmission line. The D triggers are used to detect the phase coincidence between the delayed clock signal and the beginning or ending signal of the time interval. Finally, the time difference can be deduced based on the position of the phase coincidence. A high precision TIMM is designed by using the FPGA chi PEP2C5Q204 and the clock interpolation technology. A high speed counter used to measure the time interval by the traditional counting method is realized using EP2C5Q204. The measurement range is expended and the number of the delay units are reduced when the clock interpolation technology is used to eliminate the positive and negative sub-error. By analyzing the experiment results, it is found that the novel clock interpolation technology has many advantages such as high precision, good temperature stability, and easy fabrication than other technologies. And the corresponding TIMM has the advantages of simple realization, good stability, and so on.