窄带干扰条件下含有未知载频的直扩信号的伪码序列估计  

Estimation of PN Sequence in DSSS Signals with Unknown Carrier Frequency under Narrow Band Interferences

作　　者：沈斌[1] 王建新[1] 

机构地区：[1]南京理工大学电子工程与光电技术学院,南京210094

出　　处：《电子与信息学报》2015年第7期1556-1561,共6页Journal of Electronics & Information Technology

摘　　要：为了解决窄带干扰条件下含有未知载频的直扩信号的伪码序列的估计问题,该文在已知码片速率和伪码周期的前提下,提出一种结合矩阵特征分解和线性调频Z变换的伪码序列盲估计算法。该方法对接收信号分段获得观察向量,并对观察向量的相关矩阵进行特征分解,最后应用改进的最小描述长度(MDL)准则和线性调频Z变换(CZT)对特征向量进行处理,可以估计出窄带干扰信号,同时还可以估计出信号的载频和伪码序列。仿真实验给出了不同干扰信号和不同伪码序列长度时算法的性能曲线,理论分析和仿真结果都表明了该方法能有效地工作在较低的信噪比下。In this paper an approach of eigen-decomposition and Chirp Z Transform （CZT） for DSSS signals with unknown carrier frequency under narrow band interferences is proposed to estimate the PN sequence. The period and chip rate of PN sequence need to be known. Firstly, the received signal is divided into vectors. Then, the eigenvalue decomposition is applied to the correlation matrix of the vectors. Finally, the narrow band interference, the carrier frequency and the PN sequence can be estimated by applying the improved Minimum Description Length （MDL） criteria and the Chirp-Z Transform （CZT） method on the eigenvectors. Simulation experiments show the performance curves at different SNRs with different periods of PN sequence under different narrow band interferences. Theory analysis and simulation results show that the approach can work effectively under low SNR.

关 键 词：扩频通信 直接序列扩频信号 伪码序列盲估计 窄带干扰 未知载频 特征分解 

分 类 号：TN914.42[电子电信—通信与信息系统]