摘要
对卫星测控中一类扩频码周期与信息码周期之比为非整数的直扩信号进行了研究,得出这类信号可建模成非周期调制直扩信号,提出并讨论了一种基于差分主元分析(D-PCA)的非周期调制直扩信号扩频码估计方法,该方法通过计算与差分序列协方差矩阵的最大特征值对应的特征向量完成信息码个数、子序列、信息码同步点等参数的估计,解决了传统矩阵分解方法在估计码序列时码序列相位模糊问题,理论分析和仿真结果表明该方法可以在低信噪比下进行有效估计。
A class of DS signal used in satellite TTC whose ratio of information code duration to PN period is not integer is investigated in this paper and it can be modeled as non-periodic modulated DS signal.Besides,an estimation method for spread spectrum code of generic non-periodic modulated DS signal based on differential PCA is proposed.This method estimates sub-sequence,count and synchronous point of information code by calculating eigenvector corresponding to the largest eigenvalue of the covariance matrix of the differential sequence,thus solving the ambiguity problem of PN code in the traditional matrix decomposition method.Theoretical analysis and simulation results show that the method is effective with the low SNR.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2013年第4期546-551,共6页
Journal of Astronautics
基金
国家自然科学基金(61032004)
关键词
非周期调制
直扩信号
扩频码估计
矩阵分解
主元分析
Non-periodic modulation
DS signal
Spread spectrum code estimation
Matrix decomposition
Principal component analysis（PCA）
