四川大学学报：工程科学版2012，Vol.44Issue(6)：143-147,5.
时变CDD-OFDM系统中的改进EM信道估计
Improved Channel Estimation for CDD-OFDM Systems in Time-Varying Channels
摘要
Abstract
For reducing the pilot overhead used in time-varying channel estimation of orthogonal frequency division multiplexing system with cyclic delay diversity (CDD-OFDM), an improved expectation-maximization (EM) based channel estimation scheme with recur- sive fashion was proposed. In this scheme, the mathematical relationship between the basis expansion model (BEM) of time-varying channels and the symbol time-averaged channel impulse response was firstly established and then used to predict the initial value of the EM based channel estimator, therefore the parsimonious parameterization properties of the BEM and the slow variations of the BEM pa- rameters could be exploited to improve the channel prediction accuracy and make the algorithm real-time, respectively. Simulation re- sults showed that when the signal to noise ratio is above 15 dB, the proposed scheme effectively reduces the error propagation of deci- sion directed channel tracking scheme, and has nearly the same bit error rate performance as that with perfect channel state informa- tion.关键词
正交频分复用/信道估计/期望最大化Key words
orthogonal frequency division multiplexing/channel estimation/expectation maximization分类
信息技术与安全科学引用本文复制引用
陈东华,仇洪冰..时变CDD-OFDM系统中的改进EM信道估计[J].四川大学学报：工程科学版,2012,44(6):143-147,5.基金项目
福建省自然科学基金资助项目 （）
侨办科研基金资助项目 （）
中央高校基本科研业务费专项资金资助项目 （）
国家自然科学基金资助项目 （）
广西无线宽带通信与信号处理重点实验室2011年度主任基金资助项目 （）
