天线阵列用于无线传感器网络的节点定位算法

Study for the Localization Algorithms Based on the Antenna Array in Wireless Sensor Networks

在无线传感器网络节点定位中，可以给锚节点装备天线阵列，通过MUSIC算法得到信号波达方向，然后利用锚节点和信号波达方向可以准确估计出未知节点的位置．但由于MUSIC算法只能估计少于阵元数的信号方向，本文提出采用二阶共轭增强的MUSIC算法，对阵列输出进行二阶共轭扩展，扩展出更多的虚拟矩阵，锚节点能估计出多于阵元数的信号方向，并能提高精度．仿真结果说明：利用二阶共轭扩展的MUSIC算法对无线传感器网络进行节点定位精度比MUSIC算法提高了40％～60％．

In the Wireless Sensor Networks, the anchor nodes equipped with antenna arrays can get DOAs by MUSIC algorithm fwstly, and then estimate the unknown nodes＇ location with the anchor nodes and the DOAs accurately. However, the number of signal directions estimated by the MUSIC algorithm is less than the number of array elements. In this paper, the SO-CAM algolithm is pro- posed by making the second-order conjugate enhanced on the array output to solve this problem. The number of signal directions estimated by the SO-CAM algorithm is more than the number of array elements. Therefore, the accuracy of this method is improved. Simulation results show that SO-CAM algorithm has improved 40% to 60% localization accuracy more than the MUSIC algorithm.