超声波多普勒频移信号提取及其硬件电路研究

Research on Ultrasonic Doppler Shift Signal Extraction and Its Hardware Circuit

超声波多普勒回波信号频率具有复杂性,回波信号频差的获取方法直接影响着测量精度。为此研究了一种多普勒频移信号的提取及其硬件电路的设计。基于多普勒流速测量原理,对回波信号进行放大、混频、滤波,从回波信号中提取有用的超声波频移信号,并对其硬件电路进行设计。该方法经过仿真验证满足要求,对下一步超声波频移回波信号的数字处理做出了铺垫,是确保多普勒超声波流量计精度的基础。

Ultrasonic Doppler echo signal frequency is complex. The method of obtaining the echo signal frequency difference directly affects the measuring accuracy. This paper studies the extraction of a Doppler shift signal and its hardware circuit design. Based on the principle of Doppler velocity measurement. The echo signal is amplified, mixed, filtered. A useful ultrasonic frequency shift signal is extracted from the echo signal and its hardware circuit design. The hardware circuit design of this method has been verified by simulation to meet the requirements. It is a good warm - up for next the frequency shift of the ultrasonic signals to make a digital processing bedding and to en- sure the accuracy of Doppler ultrasonic flowmeter.