一种多径信道直扩信号伪码序列盲估计方法

针对多径信道下直接序列扩频信号伪码序列盲估计的难题，拓展了基于加性高斯白噪声信道提出的子空间法，提出了一种基于子空间法和三阶相关函数法相结合的多径信道直扩信号伪码序列盲估计的新算法，进行了理论推导。该算法对接收到的多径直扩信号按照伪码周期的两倍进行分段形成数据向量，构造自相关矩阵并进行特征值分解得到不同增益伪码序列的延迟叠加，运用m序列的三阶相关特性估计生成多项式进而估计伪码序列。计算机仿真结果验证了该算法的有效性。

Approach to blind estimation of pseudo random code sequence for DSSS signal in multipath

In order to solve the problem of blind estimation of Pseudo random（PN） code sequence for Direct Sequence Spread Spectrum（DSSS） signal in multipath channel, this paper expands the application scope of subspace method which is proposed in additive gaussian white noise channel, proposes a new algorithm combining subspace method and Triple Correlation Function（TCF） method, and carries out theoretical analysis. The algorithm’s processes are as follows: section the received multipath DSSS signal according to two times the length of PN code sequence to get a group of data vector, then structure autocorrelation matrix and do Eigenvalue Decomposition（EVD） to obtain the overlapped PN code sequence of different gains and different paths, finally, estimate the generate polynomial and PN code sequence using the TCF of m sequence. The computer simulation shows that the algorithm is effective.