College of Computer Science, Zhejiang University, Hangzhou, 310027, China; E-Mails:
Sensors (Basel). 2009;9(8):6150-70. doi: 10.3390/s90806150. Epub 2009 Aug 4.
Localization is one of the most important subjects in Wireless Sensor Networks (WSNs). To reduce the number of beacons and adopt probabilistic methods, some particle filter-based mobile beacon-assisted localization approaches have been proposed, such as Mobile Beacon-assisted Localization (MBL), Adapting MBL (A-MBL), and the method proposed by Hang et al. Some new significant problems arise in these approaches, however. The first question is which probability distribution should be selected as the dynamic model in the prediction stage. The second is whether the unknown node adopts neighbors' observation in the update stage. The third is how to find a self-adapting mechanism to achieve more flexibility in the adapting stage. In this paper, we give the theoretical analysis and experimental evaluations to suggest which probability distribution in the dynamic model should be adopted to improve the efficiency in the prediction stage. We also give the condition for whether the unknown node should use the observations from its neighbors to improve the accuracy. Finally, we propose a Self-Adapting Mobile Beacon-assisted Localization (SA-MBL) approach to achieve more flexibility and achieve almost the same performance with A-MBL.
定位是无线传感器网络(WSNs)中最重要的课题之一。为了减少信标数量并采用概率方法,已经提出了一些基于粒子滤波器的移动信标辅助定位方法,例如移动信标辅助定位(MBL)、自适应 MBL(A-MBL)和 Hang 等人提出的方法。然而,这些方法出现了一些新的重要问题。第一个问题是在预测阶段应该选择哪个概率分布作为动态模型。第二个问题是未知节点在更新阶段是否采用邻居的观测值。第三个问题是如何找到自适应机制,在自适应阶段实现更高的灵活性。在本文中,我们给出了理论分析和实验评估,以建议在预测阶段应该采用哪种概率分布来提高效率。我们还给出了未知节点是否应该使用其邻居的观测值来提高准确性的条件。最后,我们提出了一种自适应移动信标辅助定位(SA-MBL)方法,以实现更高的灵活性,并获得与 A-MBL 几乎相同的性能。