无线传感器节点信号线的电磁防护实验研究

Experimental Study on Electromagnetic Protection of Signal Lines of Wireless Sensor Nodes

构建带有故障自检测功能的实验平台,使用强电磁脉冲发生器进行辐照实验;基于辐照实验结果,设计了一套软硬件相结合的防护方法,其中软件采用中值滤波,硬件采用TVS二极管;实验结果表明:无线传感器节点信号线接口自身有一定的抗强电磁脉冲能力,但随着脉冲峰值场强的增大,通过节点信号线耦合进入节点内部的大电流会导致节点出现通信错误、重启和死机等故障;添加该防护方案后,中值滤波能够有效排除瞬时性错误信号,TVS通过构建低阻通道泄放部分能量,将信号线对地电压钳位在一定范围,从而阻止大电流耦合进入节点内部,进而大幅度提高了节点的抗强电磁脉冲能力。

An experimental platform with fault self-detection function was constructed and a strong electromagnetic pulse irradiation experiment was performed using a strong electromagnetic generator.A set of protection methods combining software and hardware was designed according to the results of irradiation experiment and the characteristics of TVS,which include the median filtering and TVS diodes.The experimental results show that the signal line interface of the wireless sensor node has certain anti-strong electromagnetic pulse capability.However,as the pulse peak field strength increases,the large current flowing into the node through the node signal line will cause the communication error and restart of the node.After adding this protection scheme,the median filter can effectively eliminate the transient error signal.The TVS bleeds part of the energy by constructing the low-resistance channel,and clamps the signal line-to-ground voltage to a certain range,thereby preventing large current coupling from entering the node.The node’s ability to resist strong electromagnetic pulses has been greatly improved.