中文摘要：

时差法超声波流量计通过检测换能器发射和接收的超声波信号的传播时间信号，实现流量的计量。超声波换能器的谐振频率及超声波信号传播过程中相位和幅值的变化等因素，会影响对超声波信号到达时间的准确计量，从而影响流量测量的精度。准确计量超声波信号的到达时刻是提升时差法超生波流量计的计量精度的关键之一。针对换能器发射和接收超声波信号的处理和获取电路进行了设计和分析，得出了实验结果和实验数据，对实验结果给出了实验分析和结论，并通过软件算法给出了进一步提高测量精度的方法。

英文摘要：

The ultrasonic flowmeter with transit-time difference method can realize the flow measurement by detecting the propagation time of ultrasonic signals between the transmit and receive from the transducer. The resonant frequency of ultrasonic transducer and the phase and amplitude changes in the process of ultrasonic signal propagation will affect the measurement precision of the arrival time of ultrasonic signal, and the measurement accuracy of ultrasonic flowmeter is affected finally. The precise measurement for arrival time of ultrasonic is one of the effective way to improve the measurement accuracy of ultrasonic flowmeter. The processing and acquisition circuit of the ultrasonic signal transmitted and received are designed and researched by the paper. The experimental results and experimental data are obtained and the experimental analysis and conclusionare given. The way to improve the measurement accuracy is given by software algorithm.