无线传感器网络中基于 DSSS 抗电力系统强电磁干扰技术研究

无线传感器网络因具备部署便利、组网灵活、运行可靠等特性得到了广泛应用。针对电力系统中强电磁环境对无线传感器网数据正常传输造成了严重干扰的问题，探讨了电力系统强电磁环境的特点，在此基础上对基于扩频技术的直接序列扩频（direct sequence spread spectrum，DSSS）进行了详细分析。首先节点检测是否受到了电磁信号的干扰，其次，中继转发节点估算信干比，根据信干比的大小采用自适应滤波器来抑制电磁干扰，从而有效地提高了传感器节点的抗电磁干扰能力。采用matlab仿真，结果表明与其他抗干扰算法相比，在强电磁环境下采用直接序列扩频技术可以有效地降低接收端的误码率并提高节点投递率，进而改善网络性能。

Research on strong resistance to electromagnetic interference technology of power system in wireless sensor network

Due to convenient deployment, flexible networking, reliable operation and other characteristics, the wireless sensor network has been widely used. However, strong electromagnetic environment of power system has interfered seriously with normal data transmission of wireless sensor network. As to this issue, this paper has explored the characteristics of strong electromagnetic occasion within the power system, from which spread spectrum technology based direct sequence spread spectrum technology is analyzed in detail. To begin with, detection is carried out to ensure whether the node is disturbed by the electromagnetic signal. What''s more, the relaying node estimates relay-to-interference ratio and the electromagnetic interference is restrained by adopting the adaptive filter in accordance with the signal-to-interference ratio. Hence,the ability of resistant to electric-magnetic interference is improved. Simulation results from Matlab show that in comparison with other anti-interference algorithms, under strong electromagnetic environment direct sequence spread spectrum technique based method is able to reduce the bit error rate (BER) at the receiver side and improve the node delivery rate. Eventually, the network performance will be promoted.