多用户下行OFDM系统中的时间公平机会调度研究  

Temporal fairness opportunistic scheduling in multiuser downlink OFDM system

作　　者：唐志华[1] 朱有团[1] 卫国[1] 朱近康[1] 

机构地区：[1]中国科学技术大学电子工程与信息科学系,安徽合肥230027

出　　处：《电路与系统学报》2009年第3期17-22,共6页Journal of Circuits and Systems

基　　金：中国高技术研究发展计划资助项目(2005AA123920)

摘　　要：本文基于单信道系统中时间公平机会调度的研究,提出了3种推广到多用户下行OFDM多载波系统中的方案。这3种方案均以子载波为单位进行调度,充分利用信道的时变和频率选择特性:方案1对每个子载波单独调度,控制参数以时隙为单位更新;方案2将时频二维的子载波串在一起调度,控制参数以子载波为单位更新;方案3同方案2,但控制参数以时隙为单位更新。仿真结果表明,这3种方案均能够在保证时间公平性的前提下,相对非机会调度较大程度地提高系统性能。并且,这3种方案对子载波数和用户数没有限制,简单高效地使用有限的无线资源。Three temporal fairness opportunistic scheduling schemes are proposed based on the research of single channel system, in order to manage the parallel subcarriers in the downlink OFDM system to utilize the time varying and frequency selectivity. The first scheme schedules each subcarrier separately, and updates control parameters per slot; the second one transfers the time-frequency two-dimensional channel resource to one-dimensional equivalent channel, and updates control parameters per subearrier per slot; the last scheme does the same as the second one, except that the control parameters are updated after scheduling all subcarriers in a slot. Simulation results demonstrate that all these schemes are able to improve the system performance greatly compared with non-opportunistic schemes, under the constraint of temporal fairness. Meanwhile, all these schemes have no extra limitations on the number of subcarrier or user, so they are efficient in terms of wireless resource utilization.

关 键 词：下行OFDM系统 时间公平性 机会调度 多用户分集 效用函数 随机逼近 

分 类 号：TN929.5[电子电信—通信与信息系统]