窄带干扰下基于子空间跟踪的扩频序列估计

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

针对窄带干扰条件下低信噪比直扩信号扩频序列(Direct Sequence Spread Spectrum,DSSS)的盲估计问题,提出了一种基于子空间跟踪的扩频波形估计算法。该方法避开了直接的特征分解求解,利用滑动窗技术取得码同步,根据求解结果可以估计出信号所夹杂的窄带干扰特征波形,并进一步消除窄带干扰估计出信号的扩频码序列。结果表明,该算法在低信噪比条件下能完成对PN码序列的精确估计,降低了数据的存储量,易于硬件实现。

To solve the problem of blind estimation of DSSS signal in narrow-band interference under low SNR,a spreading sequence estimation algorithm based on the subspace tracking is proposed.This method avoids the direct eigen decomposition,and uses the sliding window technique to obtain the code synchronization.The estimated results can be used to estimate the mixed narrowband interference,and further eliminate the narrowband interference and estimate PN code.The results show that the algorithm can complete the accurate estimation of PN code sequence in low SNR conditions,reducing the amount of data storage,easy hardware implementation.