摘要
针对时差法超声波流量计时间测量的高精度要求,设计了一种结合可编程逻辑器件(FPGA)、数字信号处理器(DSP)和单片机的系统,提高了系统的稳定性和可靠性;利用改进的时差法避免了由于环境温度变化带来的影响;采用FPGA实现时序控制,并通过插值相关法提高了时间测量的精度,时间分辨率达到了1.25ns。试验证明,本系统抗干扰能力强,工作性能稳定,测量精度高。
Aiming at the high precision requirement of time measurement of time difference ultrasonic flowmeter, a system based on FPGA, DSP and MCU is designed in order to improve the stability and reliability. An improved time difference method is presented to avoid the effect of environment temperature fluctuation. By using interpolating correlation method, the time measurement precision is improved and the time resolution is 1.25ns. It is proved by experiment that the system runs stably and has enough high precision and strong anti-disturbance capability.
出处
《仪表技术》
2008年第9期8-10,25,共4页
Instrumentation Technology
基金
深圳市科技局项目资助(05KJfb043)
关键词
时差法超声波流量
高精度
延迟窗口
相关法
travel time ultrasonic flowmeter
high precision
delay window
correlation
