摘要
针对多速率长码直扩码分多址(LC-DS-CDMA)信号的扩频码估计问题,提出一种利用三阶相关特征信息的匹配估计法。利用m序列三阶相关函数峰值点具有唯一性的特点,构建周期与非周期多速率LC-DS-CDMA信号的三阶相关特征信息矩阵。根据接收信号的长度判断信号的周期性,估计相应接收信号的延迟三阶相关列向量。与相应的特征信息矩阵作匹配运算并对匹配结果进行归一化,完成接收信号中各用户的扩频码估计。仿真结果表明,该方法能够有效估计多速率LC-DS-CDMA信号的扩频码,相比盲源分离法具有更高的正确估计率。
Aiming at the problem of spreading code estimation of multi-rate Long Code Direct Sequence Code Division Multiple Access( LC-DS-CDM A) signal,a matching estimation method based on triple correlation feature information is proposed. Considering the uniqueness of the peak value of the triple correlation function of m-sequence,the triple correlation characteristic information matrix of periodic and aperiodic multi-rate LC-DS-CDM A signals is constructed.According to the length of the received signal,the periodicity of the received signal is judged,and the triple correlation column vector of the corresponding received signal is estimated. By matching with the corresponding characteristic information matrix and normalizing the matching results,the spreading code estimation of each user in the received signal is completed. Simulation results show that the proposed method can effectively estimate the spreading code of multi-rate LC-DS-CDM A signal,and the correct estimation rate is higher than using the blind source separation method.
引文
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