基于FPGA的纳秒量级脉冲宽度精确测量研究

A nanosecond level measurement method of pulse width based on FPGA

为使测量光电开关发出的数字脉冲宽度的精度达到1 ns和掌握光电开关的实时工作状态。该文通过基于FPGA精确测量法的直接计数法和移相计数法进行测量,得出移相计数法的测量误差在1 ns左右,并验证其设计的正确性和有效性。设计通信系统和上位机软件进行实时监控,通信系统采用成熟的串口RS232通信方式,用PFGA设计串口通信模块,实现将数据传输到工控机;再用LabVIEW编写上位机软件,便于工作人员直观观察数据并存储数据到Excel,实验结果证明测量系统可靠、有效。

In order to make the width of digital pulse generated by photoelectric switch reach the precision of 1ns approximately grasp the real -time working state of the photoelectric switch. This paper proposed two FPGA -based accurate measurement methods to measure the precision, directing counting method and phase shift counting method were included. The experiments show that the error of the phase shift counting method is about 1 ns, which verifies its correctness and effectiveness. The communication system and software of IPC were also designed in this paper. The communication system used a RS232 serial interface and the serial communication module transfers data to the IPC was designed by FPGA; IPC software was written by LabVIEW, which enables the data to be observed intuitively and stored to Excel easily. The experimental results show that the design of the system is correct and effective.