摘要
在正交频分复用(OFDM)系统发射端设计特殊的预编码形成了零前缀单载波(ZP-SC),其具有常规单载波和多载波的优势。文中建立了零前缀线性调制单载波(ZP-SCLD)的连续时间基带信号模型,并从信号模型出发,利用时变累积量与循环累积量的关系以及成型滤波器的频域性质推导了循环自相关函数的表达式,分析了ZP-SCLD信号循环自相关的性质,最后通过建立多径衰落信道下的信号模型分析了多径衰落信道对循环自相关性质的影响,证明了多径衰落信道虽然改变了信号循环自相关的幅度和相位,但未改变信号的循环频率,为调制识别和参数估计等信号处理环节提供鲁棒性非常强的特征。理想信道和多径衰落信道Proakis’C信道下的仿真实验证明了理论分析的正确性。
Zero-padding single carrier（ZP-SC） is such one kind of signals that is formed by designing special precoding before transmitting the orthogonal frequency division multiplexing（OFDM） signal. There- fore, it has the advantages of the conventional single carrier and the OFDM. The continuous-time baseband equivalent of zero-padding signal carrier linear digital（ZP-SCLD） signal has been given. Based on the equiva- lent, the analytical closed-form expression for the cyclic autocorrelation function（CAF） of ZP-SCLD is de- rived according to the relationship of time-varying cumulants and cyclic cumulants and the frequency domain properties of the pulse shape. Meanwhile, the properties of CAF for ZP-SCLD is also investigated. At last, it is shown in this paper that, although the multipath fading channels change the magnitude and phase of the CAF, but don＇t change the cycle frequency. Simulation results in the ideal and Proakis＇C channels sustain the theoretical analysis.
出处
《雷达科学与技术》
2012年第6期624-628,共5页
Radar Science and Technology
基金
国家科技重大专项(No.2011ZX03003-003-02)
关键词
零前缀单载波
循环平稳
循环自相关
多径衰落
zero-padding single carrier
cyclostationary
cyclic autocorrelation function
multipath fading
