一种新的采用LFM波的超声液位测量技术研究

超声是液位测量的主要技术之一,但传统的超声液位测量技术在测量准确性等方面还存在不足.研究表明优化系统发射波形可以明显提高测量的准确性和距离分辨力.采用线性调频(linear frequency modulated,简称LFM)波形发射及回波信号能量压缩、优化测量系统、引入渡越时间修正量,形成一种新的超声液位测量技术,并进行实验验证.实验结果表明:液面静止状态下,线性调频波激励方式渡越时间修正前与修正后的测量绝对误差比单脉冲激励方式最少减小分别为0.595 mm和1.52 mm;液面波动状态下,线性调频波激励方式渡越时间修正前与修正后的测量均方误差比单脉冲激励方式最少减小分别为0.487 mm和1.39 mm.

Study of a new ultrasonic liquid level measurement technology by using linear frequency modulated wave

The ultrasonic is one of the liquid level measurement methods,however,the traditional one still has shortages in many aspects including the accuracy of measurement.The research results demonstrated that the system of transmitting wave which was optimized could improve the accuracy of measurement and distance resolution.A new ultrasonic liquid level measurement technology was formed in this paper which was verified through experiments by using LFM(linear frequency modulated) wave transmission,echo signal energy compression technology,measurement system optimization and revising the escape time by experiment.The experimental results showed that the measuring absolute error decreased at least 0.595 mm of the LFM wave driving method and decreased at least 1.52 mm after revising the escape time compared with the single impulse modulated wave driving method when the liquid was at rest.Meanwhile,the measuring mean-square error decreased at least 0.487 mm of the LFM wave driving method and decreased at least 1.39 mm after revising the escape time compared with the single impulse modulated wave driving method when the liquid fluctuated.