小波去噪的低信噪比直扩信号扩频码盲估计算法

o aim at the problem of blind estimation of low-SNR DS/SS signals spreading sequence, this paper proposes to preprocess DS/SS signals applying to wavelet denoise approach, then eigenvalue decomposition algorithm、neural network algorithm and projection approximation subspace tracking algorithm are used to blind-estimation of DS/SS signals PN spreading sequence. A comparision of the performance of estimating spreading sequence before and after denoise in the algorithms is included in this paper. Computer simulation results show that the algorithms of estimating spreading sequence after wavelet denoise can work well for signals with lower SNR, and application of the algorithms will be more extensive.