摘要
针对无线电监测和认知无线电系统中正交频分复用(OFDM)信号参数估计这一重要问题,提出了用频域累积法算OFDM信号的循环自相关函数的数值计算方法.首先从理论上证明了加循环前缀的OFDM信号具有循环平稳性,并推导了OFDM信号的循环自相关函数表达式,对循环自相关函数的3维结构进行了分析.通过对OFDM信号进行数值仿真,验证了算法在低信噪比条件下,对OFDM信号的符号周期和有用符号时间参数的估计有较好的性能,实现了OFDM信号多个参数的盲估计.
To explore the parameter estimation of OFDM signals in radio monitoring and cognitive radio systems,a numerical calculation method is propose based on frequency domain accumulation for the cyclic autocorrelation function（CAF） of OFDM signals.Firstly,we have demonstrated the cyclostationarity of the OFDM signals with cyclic prefix.The CAF expressions of OFDM signals are derivated and the three-dimensional structure of the CAF is analyzed.The high performance of the method to estimate the symbol time and symbol useful time of OFDM signals with low SNR is proved by simulations.It can effectively estimate mutiple parameters of OFDM signals blindly.
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第2期118-121,共4页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(10776040)
重庆邮电大学移动通信技术重点实验室开放研究基金资助项目
关键词
认知无线电
盲信号处理
循环自相关函数
正交频分复用
参数估计
cognitive radio blind signal processing cyclic autocorrelation function orthogonal frequency division multiplexing（OFDM） parameter estimation
