基于谐波雷达的新型裂缝传感器设计  

Design of a Novel Crack Sensor Based on Harmonic Radar

作　　者：郑俊飞 王健[1] 夏银水[1] 夏桦康 ZHENG Junfei;WANG Jian;XIA Yinshui;XIA Huakang(Faculty of Electrical Engineering and Computer Science,Ningbo University,Ningbo Zhejiang 315211,China)

机构地区：[1]宁波大学信息科学与工程学院

出　　处：《传感技术学报》2019年第9期1297-1302,共6页Chinese Journal of Sensors and Actuators

基　　金：国家自然科学基金项目(61671257)

摘　　要：基于谐波雷达原理,设计了一种工作在基频为f 0=2.45 GHz的无源无线裂缝传感器。该传感器介质基板采用0.254 mm厚的超薄型双面覆铜板,整体结构包括基频接收天线、谐波发射天线、整流倍频器、二次谐波带阻滤波器和发光报警电路。当传感器处于“断裂”状态时,二次谐波带阻滤波器枝节与传感器电路断开,此时传感器将二次谐波信号发送到阅读器实现远距离报警,同时传感器整流电路产生的直流信号将给后端发光报警电路供电以实现位置报警。当传感器处于“完整”状态时,由于二次谐波带阻滤波器短路枝节的存在,使传感器产生的直流信号无法给后端电路供电,且二次谐波信号无法到达阅读器进行报警。实验结果表明,在“断裂”状态下,当发射功率为20 dBm时,阅读器与传感器之间的工作距离可以达到5.5 m,传感器发光报警电路正常工作范围可达0.8 m。Based on the principle of harmonic radar,a passive wireless crack sensor based on the fundamental frequency f 0=2.45 GHz has been proposed.The sensor is fabricated on the ultra-thin double-sided copper substrate with thickness of 0.254 mm and consists of a fundamental frequency receiving antenna,a harmonic transmitting antenna,a rectifier frequency multiplier,a second harmonic band-stop filter and a light-emitting alarm circuit.When the sensor is in a‘broken’state,the second harmonic band-stop filter branch will be disconnected from sensor circuit.Then,the sensor will transmit the second harmonic signal to the reader to realize the long-distance alarm.At the same time,the DC part of the signal generated by the sensor circuit supplies power for the back-end light-emitting alarm circuit to realize position information.When the sensor is in a‘complete’state,due to the existence of short circuit branches of the second harmonic band-stop filter,the DC voltage generated by the sensor cannot supply power to the back-end circuit and the second harmonic signal cannot reach the reader for alarm.Experimental results show that in a‘broken’state,when the transmitting power is 20 dBm,the working distance between the reader and the sensor can reach 5.5 m and normal working range of sensor light-emitting alarm circuit can reach 0.8 m.

关 键 词：裂缝传感器 谐波雷达 整流倍频器 二次谐波带阻滤波器 

分 类 号：TN455[电子电信—微电子学与固体电子学]