中文摘要：

针对超声波传输时间精密测量的要求，提出了一种精密测量超声波传输时间的方法．该方法以高分辨率高精度A／D和高速FPGA作为硬件核心，保证了超声波回波信号采样数据的高分辨率和实时性．精密测量超声波传输时间的软件算法综合了整个超声波回波信号采样数据，利用细分插补算法精确计算超声波传输时间的终点时刻，保证了超声波传输时间测量的高精度．实验表明，该方法能够在不增加生产成本的前提下，达到ns级．乃至ps级的超声波传输时间精密测量．

英文摘要：

In accordance to the requirements of precisely measuring ultrasonic transmission time, a measurement method with high precision was proposed. The high-resolution A/D and high- speed FPGA were adopted as the core of hardware system to guarantee the instantaneity of ultrasonic echo. The sample data of entire ultrasonic echo were synthesized in software algorithm, and the arithmetic of software interpolation subdivision was employed to accurately calculate the end point of ultrasonic transmission time, so that the precision measurement of ultrasonic transmission time was ensured. Experiments show that, without increasing production costs, the method achieves the accuracy of measuring ultrasonic transmission time in nanoseconds level, even in picoseconds level.