摘要
在LTE系统中,基站根据移动终端反馈上传的信道质量指示(CQI)进行自适应调制编码和调度无线资源,由于CQI的生成和上传时延,调度器实际上使用的是延迟的CQI。文中通过系统建模和自行开发的仿真平台详尽分析了CQI延迟特性及其对下行调度产生的影响,结果表明随着CQI时延的增加和终端运动速度的上升,调度效率会有明显的下降,但是在终端低速移动的情况下使用延迟较短的CQI进行调度仍然是一个比较好的选择。
In LTE systems, the base stations use terminal fed channel quality indicator （CQI） to schedule radio resources and select the proper modulation and coding scheme. In fact, the CQI used by the schedu- ler is outdated due to the delay incurred by its generation and uplink transmission. Employing the ap- proach of system modeling and self-developed simulation platform, we give an in-depth analysis of the characteristics of outdated CQI and its impact on LTE downlink scheduling. Simulation results show that, with the increase of CQI delay and terminal moving speed, the scheduling efficiency will be degraded sub- stantially. However,using the outdated CQI with low delay is still a good choice to do scheduling for the terminals moving with low speed.
出处
《南京邮电大学学报（自然科学版）》
北大核心
2012年第6期12-16,共5页
Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition
基金
国家自然科学基金(60872018)
国家科技重大专项(2011ZX03005-004-03)资助项目
