一种简单高精度超声液位计系统的设计与实现

介绍了超声时延法测距的基本原理,设计并实现了一种基于DSP的超声液位计系统,改进国内同类产品精度和稳定度偏低的问题。利用选用的AD、DSP芯片特点,给出了一种简单高效率的超声换能器驱动电路和回波采集放大电路的实现方案;使用通用16位定点DSP芯片TMS320VC5502,实现测距算法,增强了后端数字信号处理能力;使用收发一体窄带超声换能器发射和接收超声信号,其中心频率20kHz,3dB带宽1kHz。实验结果表明,本系统测量范围为0.5～18m,测量精度可达到测量距离的0.5%。

Design and implementation of a high precision simple ultrasonic liquid level meter

The paper presents the design and implementation of an ultrasonic level measurement system based on DSP which has high precision and stability.Ultrasonic time-delay method for range measurement is utilized.According to the characteristics of AD and DSP we use,a high efficient driving circuit for transducer and echo collecting and amplifying circuit are explained in detail.A 16-bit fixed-point DSP TMS320VC5502 is used for digital signal processing with special algorithm.A narrowband ultrasonic transducer is used to transmit and receive signals,with the central frequency at 20 kHz and bandwidth of 1 kHz. The measure’s results show that the system can obtain measure precision up to 0.5%relative to the real distance with a measure range from 0.5 to 18 meters.