基于多组播无线网络编码子图优化问题的研究

Research on Subgraph Optimization Based on Multiple Multicast with Network Coding in Wireless Network

文中主要针对存在链路耗损的无线多组播网络模型,考虑存在链路时延且中间节点缓存受限情况下的基于网络编码技术的最小费用优化问题。为解决该优化问题,首先构造它的连续时间模型,然后进一步得到它的离散时间模型,为了方便问题解决,引入时间扩展网络模型将问题转化为无时延问题,最后提出该优化问题的分布式求解算法,并通过仿真研究了节点缓存大小分配,以及链路耗损情况对系统总费用的影响。仿真结果显示,链路耗损会大大增加系统的总能耗,同时缓存器的大小也直接影响系统的能耗,可通过增大缓冲器的大小来减少系统能耗。

In this paper,in view of the wireless multiple multicast model with link lossy, the minimum cost optiminization problem is con- sidered based on network coding under the condition of being link delay and limited buffer-size of intermediate nodes. To solve the prob- lem,introduce the time-expanded network model to turn the problem into the continuous-time problem. Finally, a distributed solving al- gorithm for this optimization is proposed, and study the node memory by simulation and the influence of link lossy on total cost of sys- tem. Simulation results show that the lossy can increase the overall energy consumption of the system,and the size of cache also directly influences the system energy consumption which can be reduced by adding the cache size.