摘要
针对多用户OFDM系统的下行链路提出了一种基于QoS的跨层资源分配策略。建立了基于有限长缓存的用户分级模型,推导了有限长缓存引起的用户速率限制条件。根据等待时延将用户分为"高级用户"和"普通用户",在保证所有用户QoS的前提下为"高级用户"优先分配子载波和功率,同时系统的吞吐量达到最大。仿真结果表明,在报文到达率较高的情况下该策略有效降低了系统丢包率,保证了吞吐量。
A new QoS-aware cross layer resource allocation scheme is proposed for the downlink of multi-user OFDM system A user-dividing model based on finite-length user buffer is build up while the user rate constraint coursed by finite-length buffer is formulated. Users are dynamical divided into "super users" and "common users" by time delay. After all the users' QoS is guaranteed, sub-carriers and power is preferentially allocated to the "super users" while maximizing the system throughput. Simulation results show that the scheme can decrease the packet drop rate and maintain high system throughput when the packet arrival rate is high.
出处
《电路与系统学报》
CSCD
北大核心
2010年第3期24-29,23,共7页
Journal of Circuits and Systems