高速移动环境中提供QoS保证的跨层调度算法

摘要

To help the scheduler make a decision in high-speed mobile communications, with a comprehensive understanding of the traffic profile and the time varying property of the mobile channel. Mobile utility was defined, which described the relationships among traffic profile, moving speed, outage capacity and mobile utility. Based on mobile utility, three scheduling algorithms in the fading channel were proposed to improve the system's average utility. The greedy method was proven to be optimal, which required high computation complexity. Then, by considering the property of the utility variation, the maximum utility gradient algorithm (MG) was proposed, which gave a better tradeoff between complexity and performance. The simulations show that the MG method with much reduced complexity approaches the optimal capacity, while significantly improving the user experience in high-speed mobile communications.%在高速移动环境中,为了使调度器充分利用信道的时变特性和业务的服务质量(QoS)特性,通过分析业务超时的概率定义了移动效用,给出了业务时延特性、移动速度、中断容量和移动效用的关系.基于移动效用,提出三种调度算法,证明了贪婪算法的最优性,但复杂度较高.为了降低复杂度,基于移动效用的时变特性进一步提出了最大化效用梯度(MG)的调度算法,仿真结果表明,该低复杂度算法在保证系统获得较高吞吐量的同时,显著地提高了高速移动环境下的用户体验.