论文标题
大规模无线传感器网络中的分布式估计通过两个步骤组的方法
Distributed Estimation in Large Scale Wireless Sensor Networks via a Two Step Group-based Approach
论文作者
论文摘要
我们考虑具有统计依赖性传感器观察的大型传感器网络中协作分布式估计的问题。在协作设置中,目的是通过对基本统计依赖性建模并有效地利用已部署的传感器来最大化整体估计性能。为了实现更大的传感器传输和估计效率,我们提出了一个基于两步组的协作分布式估计方案,在第一步中,传感器形成依赖驱动的组,以使同一组中的传感器高度依赖,而来自不同组的传感器则是独立的,并且可以通过内部协作执行基于Copula的最大值posteriori Probority(MAP)估计。在第二步中,第一步中产生的估计值通过组间协作共享,以达成平均共识。提出了基于合并的K-密尔类依赖性驱动分组算法。此外,我们在估计之前使用共同信息进一步提出了一种基于组的传感器选择方案。目的是在某些预先指定的能量约束下选择有关感兴趣的参数具有最大相关性和最小冗余性的传感器。同样,提出的基于组的传感器选择方案被证明与具有高概率的全球/非组选择方案相当,但在计算上更有效。进行数值实验以证明我们方法的有效性。
We consider the problem of collaborative distributed estimation in a large scale sensor network with statistically dependent sensor observations. In collaborative setup, the aim is to maximize the overall estimation performance by modeling the underlying statistical dependence and efficiently utilizing the deployed sensors. To achieve greater sensor transmission and estimation efficiency, we propose a two step group-based collaborative distributed estimation scheme, where in the first step, sensors form dependence driven groups such that sensors in the same group are highly dependent, while sensors from different groups are independent, and perform a copula-based maximum a posteriori probability (MAP) estimation via intragroup collaboration. In the second step, the estimates generated in the first step are shared via inter-group collaboration to reach an average consensus. A merge based K-medoid dependence driven grouping algorithm is proposed. Moreover, we further propose a group-based sensor selection scheme using mutual information prior to the estimation. The aim is to select sensors with maximum relevance and minimum redundancy regarding the parameter of interest under certain pre-specified energy constraint. Also, the proposed group-based sensor selection scheme is shown to be equivalent to the global/non-group based selection scheme with high probability, but computationally more efficient. Numerical experiments are conducted to demonstrate the effectiveness of our approach.