摘要
以系统总速率最大化为目标,基于迫零污纸编码(ZF-DPC)机制提出了 MIMO 多用户下行系统的一种保障用户 QoS 的自适应调制方案。根据这一方案,基站应用空分多址接入(SDMA)同时支持多个用户;针对污纸编码(DPC)的极高复杂度,利用次优的 ZF-DPC 消除用户间的干扰;在理想信道信息情形下实现可变速率可变功率自适应调制。考虑到最优算法的高复杂度,提出了两种可应用到实际系统的低复杂度次优算法。仿真结果表明,次优算法在极大降低系统复杂度的同时,总速率比较接近最优算法的性能。
Based on the zero-forcing dirty-paper coding （ZF-DPC） mechanism, this study presented an adaptive modulation scheme for downlink multi-user MIMO systems to maximize systems＇ sum-rate and achieve a guaranteed QoS for users. Specifically, according to the scheme, the basestation exploits spatial division multiple access （SDMA） to support several users＇ simultaneous transmission, and the suboptimal ZF-DPC to reduce inferences among users because of the high complexities of dirty-paper coding （DPC）. Then an adaptive modulation scheme with variable rate and variable power was achieved under perfect channel state information at the basestation. Because the brute-force search is eomputationally prohibitive, two low-complexity suboptimal algorithms which could be used in practical systems were proposed. Simulation results showed that the suboptimal algorithms achieved almost the same performance as the optimal one at the same time the system complexity was greatly reduced.
出处
《高技术通讯》
CAS
CSCD
北大核心
2008年第4期336-340,共5页
Chinese High Technology Letters
基金
863计划(2006AA01Z277)
国家自然科学基金(60496315)资助项目
