无线网络中网络编码子图优化问题的研究

文中主要针对存在链路时延且节点缓存受限的无线网络来考虑网络编码子图优化问题。提出所研究问题的连续时间模型，进而又推导出离散时间模型。为简化所研究问题，引入时间扩展网络拓扑模型，基于该模型提出网络编码子图分布式优化算法，并通过仿真评估节点缓存大小对系统性能的影响。仿真结果表明，节点缓存越长，最优子图的总能耗越少。最后，对比网络编码技术和路由技术对系统性能的影响，仿真结果表明有网络编码的系统性能优于传统的无网络编码系统。

Research on Optimal Sub-graph Selection with Network Coding in Wireless Networks

Consider the problem of finding a minimum cost multicast sub-graph over wireless networks based on network coding,where delay values associated with each link,limited buffer-size of the nodes are taken into account. For such networks,the continuous-time model is formulated,and the discrete-time model is derived. To simplify the problem,introduce the time-expanded network topology model. Then,a distributed optimized algorithm of network coding sub-graph based on this model is proposed. As shown by the simulation results,larger buffer-size of the nodes may lead to cost reduction,and the performance of the system with network coding outperforms the traditional system.