应用线性调频信号的智能超声液位仪  

Intelligent ultrasonic measure apparatus for liquid level based on linear frequency modulation signal

作　　者：臧怀刚[1,2] 李刚[1] 王丹丹[1] 

机构地区：[1]燕山大学工业计算机控制工程河北省重点实验室,秦皇岛市066004 [2]北京理工大学信息科学技术学院电子工程系,北京市100081

出　　处：《微计算机信息》2010年第7期120-122,共3页Control & Automation

摘　　要：利用超声波从液罐外部观测封闭罐中的液位时,由于超声波传感器被安装在液罐的底部,而液罐往往处于复杂的工业环境下,存在各种工业噪声信号的干扰;同时罐内气体及气泡的存在,对超声信号造成了散射,影响了测量的准确性。为了解决问题,,本文采用了线性调频(linear frequency modulation,LFM)信号结合匹配滤波应用于液面检测。由于匹配滤波是对于高斯白噪声背景下LFM信号的最优检测器,使得系统具有很好的抗干扰性;同时这种方法的运用缩小了盲区的范围,并可提高量程。这一成果将为从外部观测封闭罐中液位的方法推广起着重要作用。When making use of ultrasonic observe a liquid level from outside of the tank,because ultrasonic sensor is fixed on the bottom of a liquid tank,the liquid tank always in complex industry surroundings,there exist many industry noise;there also exist gas and air bubble in the tank,it make ultrasonic scatter and get measure more error.For solving the contradiction,this paper adopt linear frequency modulation（LFM） signal and matched filter to realize the purpose.For matched filter is optimization check-up implement for LFM signal with gauss noise,it make the system has good anti-jamming.Utilizing this method also reduce the range of blind zone and increase the measure range.This result will bring into play an important effect for popularizing the method observing liquid level in the sealed tank from outside of the tank.

关 键 词：线性调频 超声波 智能 液位 

分 类 号：TB55[理学—物理]