基于移动信标的无线传感器网络混合节点定位算法

A Hybrid Localization Algorithm Based on Mobile Beacons for Wireless Sensor Networks

节点定位是无线传感器网络中的关键技术之一。本文在采用装备有GPS装置的移动信标的基础上,提出了加权质心定位方法和Unscented-KF滤波组合定位算法。算法首先利用加权质心定位方法,获得无线传感器网络未知节点的初步位置,再用Unscented-Kalman filter进一步提高定位精度。算法可以实现传感节点的低成本定位,容易达到很高的定位精度、可实现分布式定位计算。仿真结果显示,与算法较常用的极大似然估计相比,未知节点的定位精度有较大的提高。本算法定位过程中节点间无通信开销,计算量小,节省了宝贵的节点能量。在本文中算法是基于RSSI测距方式,它还可应用于TDOA,TOA等基于测距的定位算法中,具有较普遍的应用意义。

Localization of nodes is a key technology for application of wireless sensor network. We propose a hybrid localization algorithm based on mobile beacons, such as mobile robots and UVA, which are equipped with GPS for wireless sensor networks. The hybrid algorithm combines weighted centroid localization method with Unscented- Kalman filter. Firstly, the algorithm gets an inaccurate position coordination of a node by weighted centroid localization method. Then the algorithm achieves an accurate localization of the node by using Unscented-Kalman filter. This algorithm is low-cost, distributed and can achieve higher accurate than maximum likelihood estimation in：our simulation. No communication is needed between nodes while positioning, so we say it is energy efficient, In this paper, the algorithm is based on RSSI. In fact, the algorithm can be applied to other localization algorithm which is based on range-based method, such as TDOA, TOA. So it can be applied to many applications.