基于窄带宽超声传感器的传播时间测量方法

摘要

为了精确地测量声波传播时间，提出了一种基于窄带宽超声传感器的传播时间测量方法。该方法无需知道初始时刻的采样数据，只利用稳定后的声波信号经过过零比较器的时间，通过直线拟合获得准确的传播时间。为了验证该方法的正确性，建立了一套超声波测量系统，其核心是现场可编程门阵列( FPGA)的设计。试验结果表明，该系统可以准确地测量声波的传播时间，通过校准，可以保证该测量系统在实际应用中的可靠性及准确性。%In order to accurately measure the propagation time of the sound wave, the method based on narrowband ultrasonic transducer is proposed. With this method, it is not necessary to know the sampling data at initial period, only the time crossing zero comparator of sound wave signal is used to obtain accurate propagation time through linear fitting. To verify the correctness of this method, a set of ultrasonic measuring system is built with the design of FPGA as the core. The experiment results show that the system can precisely measure the propagation time of sound wave, after calibrating, the reliability and correctness of the system can be ensured in practical applications.