Ad Hoc网络中改善拓扑控制性能的移动控制算法

Movement Control Algorithms for Improving Topology Control Performance in Ad Hoc Networks

在无线Ad Hoc网络中,拓扑控制算法能够使节点的传输功率小于最大传输功率,从而可以节省网络能量,提高网络容量.由于节点分布的随机性,在节点较为稀疏的区域,拓扑控制算法存在着局限性,因而提出了移动控制算法来改善拓扑控制算法的性能.在保证网络连通性的前提下,算法首先根据收集到的信息,通过构造网络最小生成树确定较长的通信链路,并移动网络中的部分节点使这些链路缩短,从而显著减小网络中较大的通信半径,提高了拓扑控制的性能.仿真实现了PMST-P,PMST-UV和LMST-LUV这3种移动控制算法,并对它们的性能进行了讨论和相互比较.

In Ad Hoc networks, topology control is designed to save energy and increase network capacity by enabling nodes to use proper transmission power, which is usually much smaller than the maximal transmission power. However, the randomicity of network deployment and node movement results in a non-uniform distribution of nodes. In a region where nodes are sparse, the distance between two nodes may be much longer than that in a dense region, so the transmission power is not able decrease and does not depend on which topology control algorithm is adopted. For the first time, this paper proposes movement control algorithms to improve performance of topology control by moving a subset of nodes to desiring positions. Based on the minimum spanning tree of the network topology graph, addition links are determined. Moreover, addition links are shortened and large communication range may be reduced by moving some nodes. Three movement algorithms, PMST-P, PMST-UV and LMST-LUV, are realized, and their performance is compared with each other with respect to maximum communication range, total moving distance and etc. using simulations.