利用张量分解的多天线长码直扩CDMA信号扩频码盲估计  

Blind estimation of spreading codes for multi-antenna LC-DS-CDMA signals based on tensor decomposition

作　　者：赵知劲[1] 尹辉 强芳芳[1] 尚俊娜[1] ZHAO Zhijin;YIN Hui;QIANG Fangfang;SHANG Junna(Telecommunication School,Hangzhou Dianzi University,Hangzhou 310018,China)

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018

出　　处：《通信学报》2018年第10期52-58,共7页Journal on Communications

基　　金：国家自然科学基金资助项目(No.61571172)~~

摘　　要：针对插补法效果不佳的多天线长码直扩CDMA信号扩频码盲估计问题,采用分段思想,将接收信号构建成的三阶张量按照扩频增益分块成等价于Tucker分解模型的子张量。然后对子张量利用变步长梯度下降算法进行Tucker分解得到扩频码片段和接收增益矩阵。根据子张量的接收增益矩阵相同的特点,利用各个子张量接收增益矩阵的互相关矩阵估计置换矩阵,去除扩频码片段排序模糊。最后利用扩频码的自相关性,去除扩频码片段的幅度模糊,得到每个用户扩频码。仿真结果验证了算法的有效性。Aiming at the problem of the poor performance of the imputation method for the spreading codes blind estimation of the multi-antenna long-code direct sequence code division multiple access(CDMA)signals.Firstly,using the segmentation idea,the received signals were constructed into a three-dimensional tensor model,and the tensor was divided into sub-tensors according to the spreading gain.The sub-tensors were constructed into the Tucker decomposition model.Secondly,the spreading code fragments and the receiver gain matrixes were obtained from the sub-tensors by Tucker decomposition which was using the variable step gradient descending algorithm.Then,because of the same characteristic of the receiver gain matrixes in each sub-tensor,the permutation matrixes were estimated by using the cross correlation matrixes of the receiver gain matrixes and the order of the spreading code fragments was corrected.Finally,the amplitude of the spreading codes was determined by using the autocorrelation of the spreading codes,and each user’s spreading code was obtained.The simulation results verify the effectiveness of the proposed algorithm.

关 键 词：长码扩频码分多址 扩频码估计 张量 Tucker分解 

分 类 号：TN911[电子电信—通信与信息系统]