无线传感器网络中一种精细距离控制定位算法

Fine-grained Distance Controlled Localization Algorithm in Wireless Sensor Networks

在Hop-terrain定位算法的基础上,提出了一个新的改进定位算法。新算法先利用由距离向量交换获得的普通节点与信标节点间的跳数距离进行传感器节点的初始位置估计;然后利用节点初始估计位置和节点直接邻居信息进行节点位置的迭代更新。在更新阶段,为了降低误差,引入了一种精细距离控制机制。该距离控制机制参考到高可信度权值邻居节点的距离约束关系,选择可能的最好节点位置作为最新迭代定位结果。仿真结果表明,与原算法相比,该算法能提高定位节点的比例,降低节点定位误差。

An improved location discovery algorithm upon previous Hop-terrain localization algorithm was proposed in this paper. At first, the algorithm used distance vector exchange to get hop counts from sensors to anchors and estimate the initial positions of sensor nodes. Then it iteratively updated the sensor nodes＇ positions by utilizing the initial position estimates and information of immediate neighbors of sensors. A fine-grained distance control mechanism was introduced in the position iteration update phase to decrease the position error. The distance control mechanism chose the possible position with great accuracy as iteration result based on the constraints of the distance to those neighbors with high weight value calculated by our algorithm. Simulation results show that the fraction of located nodes is increased and the position error is decreased compared with Hop-terrain algorithm.