基于超声波气体传感器的飞行时间测量系统  

Time-of-flight measurement system based on ultrasonic wave gas transducer

作　　者：崔园园[1] 王伯雄[1] 柳建楠[1] 李伟[1] 

机构地区：[1]清华大学精密仪器与机械学系精密测试技术及仪器国家重点实验室,北京100084

出　　处：《传感器与微系统》2013年第6期98-100,107,共4页Transducer and Microsystem Technologies

基　　金：国家"863"计划资助项目(2008AA042207);清华大学精密测试技术与仪器国家重点实验室自助研究课题

摘　　要：提出并搭建了一种基于双向回波法和数字相关法的超声波飞行时间测量系统。利用双向回波法标定传感器的电路延迟,获取测量时所用的参考信号。以参考信号和接收信号之间二重相关函数的最大值处作为粗糙定位点,在其附近对经希尔伯特变换后的函数进行线性插值,获取过零点作为最终的时间测量值。系统的标定精度能达到fs级,单次测量精度能够达到几纳秒至几十纳秒。该系统的优势是能够以低配模式获得高精度且可信赖的飞行时间测量结果,可应用于距离、流量和风速测量等领域。A time-of-flight measurement system based on bi-echo method and digital correlation method is proposed and built.Bi-echo method is used to calibrate circuit delay of sensor and obtain reference signal for measurement.Take the maximum location of two-layer correlation function between reference signal and receiving signal as coarse location point,by linear interpolating the Hilbert transform function around this coarse location point,the zero-crossing point is acquired to be the final measurement value of time-of-flight.The calibration precision of the system can reach fs level,and the single measurement precision can reach a few ns.The system can obtain reliable and precise ultrasonic time-of-flight,and can be applied to the fields of distance,flow and wind velocity measurement.

关 键 词：超声波 飞行时间 希尔伯特变换 数字相关 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]