无线mesh网络中一种干扰优化与覆盖优先的组播路由机制

An Interference Optimized and Coverage First Scheme for Multicast Routing in Wireless Mesh Network

提出干扰优化与覆盖优先的组播路由机制IOCFMR.组播路由问题实质为组播树的构建问题,IOCFMR首先在构建组播树的过程中每一步选择干扰最小的最短路径加入树中,建立干扰优化的组播树;然后,针对接收端覆盖用户数量的不同,定义接收端信道分配优先级,提出了覆盖优先的信道分配算法,该算法根据组播树中节点优先级,选取对组播树干扰最小的信道作为节点发送信道,干扰度量考虑了隐节点问题以及干扰影响的用户数量.在形成信道分配的初始方案后,该算法对其进行再一次优化以消除在逐步分配信道过程中未能发现的干扰问题.仿真实验表明本文提出的组播路由机制在性能上好于M4和MCM算法.为评估覆盖优先的意义,定义了用户满意度指标用来描述接收端覆盖的用户数量与性能的关系,实验表明,与M4和MCM算法相比,用户满意度分别提高29.8%和42.7%,本文算法在用户覆盖优先方面达到了较好的效果.

In this paper, a scheme IOCFMR is proposed for interference optimized and coverage first multicast routing in wireless mesh networks. The multicast routing problem is to build a routing tree for packets transmission. First, in each step of multicast rou- ting tree constructing, a path to one of receivers with minimum interference is selected and joined into the routing tree, and an inter- ference optimized multicast routing tree would be build up finally. Then, considering the user number of each receiver, the priority metric for each receiver is defined and used for channel assignment in the routing tree. A channel assignment algorithm is proposed for interference optimized and coverage first multicast routing. The proposed algorithm assigns the channels to each node in the tree ac- cording to their priorities, and in each step, the channel with minimum interference to neighbors would be selected considering the hidden node problem and the involved user number. Moreover, for the remove of interference which can＇t be found in the iteration step, the further optimization is done to the initial channel assignment solution. At last, simulation is done, and the proposed scheme outperforms the other two algorithms. As far as the user number priority is concerned, compared with M4 and MCM, the proposed scheme has the performance increased by 29.8 % and 42.7 % respectively.