电磁超声接收系统的设计与实现  

Design and Realization of Receiving System of Electromagnetic Acoustic

作　　者：李固[1] 陈鹏[1] 边雁[2] 王帅[1] 

机构地区：[1]军械工程学院电气工程系,河北石家庄050003 [2]西安电子科技大学生命科学技术学院,陕西西安710065

出　　处：《仪表技术与传感器》2011年第8期85-87,共3页Instrument Technique and Sensor

摘　　要：提出了一种由正交矢量锁相发大器为核心构成的电磁超声接收系统,该系统针对电磁超声换能器(EMAT)换能效率低,噪声干扰大的现状,以及锁相放大在提取噪声中微弱信号方面的优异性能,采用模拟与数字相结合的方式完成整个接收系统的设计。在该方案中,整个接收电路围绕由平衡调制解调器AD630构成的相敏检波器(PLD)展开,分别设计了信号通道、参考信道和相关器电路,并给出了相关的电路设计图。最后通过实验对比验证,证明该系统可以从噪声中提取出微弱的检测信号,且消噪效果明显,提高了信噪比。As a result of superior property of lock-in ampfilier（LIA）technique in weak signal testing and present problem that electromagnetic acoustic testing is high noise and low conversion efficiency,this paper presented an electromagnetic acoustic receiving system combined with analog and digital by the core of the lock-in amplifying technique based on cross-correlation theory.The receiving circuit was designed around PLD consisted of AD630,which contained signal channel,reference passage and correlator.The experimental results prove that the receiving system has high accuracy and it improves signal-to-noise ratio.

关 键 词：电磁超声 锁相放大 接收系统 互相关理论 相敏检波器 

分 类 号：TG115.28[金属学及工艺—物理冶金]