无线多跳网络(wirelessmultiple—hopnetworks,WMN)是近年来快速发展的网络技术,具有可靠性高、网络扩展性好等优势,但其通信环境多跳以及动态自组织的特点,给多媒体业务的应用带来了巨大的挑战。在本文中,提出了基于网络效用最大化(networkutilitymaximization,NUM)的跨层联合优化算法,此算法是一种联合传输层、MAC层、物理层,利用凸优化方法,以网络效用最大化为目标的TCP速率控制和MAC接入竞争跨层联合优化算法,在保证多媒体业务端到端的QoS(qualityofservice)服务质量前提下,最大限度地提高网络的整体吞吐量。仿真结果表明,此算法可以根据本地网络信息,对系统进行全局优化,大大降低了系统的时延,提升了系统的吞吐量,同时能够满足应用的Qos要求。
The wireless mutiple-hop network has a rapid development as a promising network technology in recent years. It has the merits of high reliability and good scalability, but its multi-hop and dynamic self-organizing feature have brought enormous challenges to the application of multimedia services. A systematic network utility maximization (NUM) based cross-layer design approach is proposed by using convex optimization methods for the joint optimization of physical, transport and MAC layers in order to maximize the network's overall throughput while providing end-to-end QoS (Quality of Service) for multimedia traffic. Simulation results show that our cross-layer optimization can be itera- tively performed based on local link information and the optimum TCP rate control and contention control parameters, which reduce the delay and maximize the system throughput while satisfying application' s QoS requirements.