基于码片延迟的多径信道扩频序列盲估计

针对多径信道下低信噪比直扩信号扩频序列的盲估计问题,提出一种通过码片延迟与相关矩阵分析相结合的方法实现扩频波形估计。该方法首先将接收信号延迟一段时间与原信号相乘,然后代入自相关矩阵中,通过特征值分解求得最大特征值及其对应的特征向量,通过该特征向量中的零点确定同步位置并恢复扩频序列。理论分析和仿真结果表明,本算法在低信噪比条件下能完成对PN码序列的精确估计。

The spreading spectrum estimation based on subspace tracking with narrow-band interference

In order to solve the problem of blind estimation of spreading spectrum sequence for DSSS under low SNR in multipath channel, a method which combines chip delay and correlation matrix analysis is proposed. In this method, a delay in the received signals is multiplie with the original signal, then structure autocorrelation matrix and do eigenvalue decomposition to obtain the eigenvector. At last, obtain the synchronization by the zero position and restore the spreading spectrum sequence. Theoretical analysis and simulation results show that the algorithm under low SNR can complete the PN code sequence precise estimates.