摘要
提出一种应用卷积码编码的VBLAST-MC-CDMA系统上行链路结构,并将自适应调制技术应用于上行链路结构中。自适应调制门限的设定采用试验法。先设定需要的误码率门限,并以此为依据通过仿真结果确定系统调制方式的转换门限。通过仿真,分别讨论了用户数固定和用户数变化时该自适应调制系统的误码率性能。仿真结果表明,两种情况下自适应调制都能在不牺牲期望误码率性能的情况下提高系统的频谱效率。
An uplink structure of convolution coded VBLAST-MC-CDMA system was proposed. The adaptive modulation techniques were applied to the system. The thresholds of adaptive modulation were set by simulation. The expected bit error rate （BER） thresholds were settled first, and then according to the BER simulation results, the conversion thresholds of modulation types of the system were determined. The BER performance of the adaptive modulation VBLAST-MC-CDMA system for a given number of users and various number of users was simulated. Simulation results show that adaptive modulation improves the spectrum efficiency of the system in both cases without sacrificing the expected BER performance.
出处
《系统仿真学报》
CAS
CSCD
北大核心
2010年第2期458-462,共5页
Journal of System Simulation
基金
国家自然科学基金(60572036
50534060)
国家"八六三"计划项目(2007AA01Z259)
东南大学移动通信国家重点实验室开放基金(W200816)
关键词
自适应调制
垂直空时分层
多载波CDMA
频谱效率
adaptive modulation
vertical Bell Laboratories layered space-time （V-BLAST）
multicarrier code division multiple access （MC-CDMA）
spectrum efficiency
