一种支持多用户QoS的跨层资源分配策略

Multi-user QoS-Supported Cross Layer Resource Allocation Scheme

提出了一种多用户OFDM系统中支持QoS的跨层资源分配策略。在MAC层采用有限长用户缓存模型,推导了丢包率要求引起的用户速率限制条件,将其作为跨层信息指导物理层资源分配过程。根据等待时延对用户进行分级,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。仿真表明,在报文到达率较高的情况下该策略既保证了吞吐量,又降低了系统丢包率。

A QoS-supported cross layer resource allocation scheme was proposed for the multi-user OFDM system. The model based on finite-length user buffer was used in MAC layer while the user rate constraints induced by packet drop rate requirement was formulated. As cross layer information, the user rate constraints helped to allocate the resource in physical layer. Users were divided into different kinds by time delay. After all the users＂ QoS was guaranteed, sub-carriers and power was preferentially allocated to the ＂＇super users ＂. Simulation results show that the packet drop rate can be decreased and system throughput maintains high when the packet arrival rate is high.