DS⁃CDMA下行链路多用户与扩频波形估计  

Waveform estimation of multi⁃user and spread spectrum in DS⁃CDMA downlink

作　　者：解辉 赵忠臣 刘利民 韩壮志 尹园威 XIE Hui;ZHAO Zhongchen;LIU Limin;HAN Zhuangzhi;YIN Yuanwei(Department of Electronic and Optics Engineering,Shijiazhuang Campus of Army Engineering University of PLA,Shijiazhuang 050003,China)

机构地区：[1]陆军工程大学石家庄校区电子与光学工程系,河北石家庄050003

出　　处：《现代电子技术》2022年第21期1-6,共6页Modern Electronics Technique

基　　金：河北省自然科学基金(F2019506037)。

摘　　要：针对现有基于信号子空间估计方法计算量较大的问题,提出一种基于信号子空间旋转的扩频波形估计方法。首先对观测数据的协方差矩阵进行特征分解,根据特征值分布情况估计用户数,同时获得信号子空间。进而利用信号子空间估计各用户的扩频波形,针对目前基于子空间高维搜索方法计算量大、实际应用性不强的问题,首次将Givens旋转思想应用于多用户扩频波形的估计,利用Givens旋转将多用户波形估计的高维搜索问题转化为多次一维搜索,并给出了相应Givens旋转的优化判据,实现了各用户扩频波形的快速估计。仿真实验结果表明,算法有效地降低了高维搜索方法求解的计算量,且能够在较低信噪比环境下同时估计多个用户的扩频波形。A spread spectrum waveform estimation method based on signal subspace rotation is proposed to reduce the calculated amount of existing methods based on signal subspace estimation.Eigen decomposition is performed on the covariance matrix of the observed data,the number of users is estimated according to the distribution of eigenvalues,and the signal subspace is obtained.Then the signal subspace is utilized to estimate the spread spectrum waveform of each user.In view of the large calculated amount of present high dimensional search method based on subspace,and weak practical applicability,the Givens rotation thought is applied to multi⁃user spread spectrum waveform estimation for the first time.Givens rotation is adopted to translate the high dimensional search into the repeated one⁃dimensional search in the multi⁃user waveform estimation.The optimization criterion corresponding to Givens rotation is given,and the fast estimation of spread spectrum waveform of each user is realized.The results of simulation experiment show that the algorithm can effectively reduce the calculated amount of the high⁃dimensional search method,and can simultaneously estimate the spread spectrum waveform of multiple users in a low SNR environment.

关 键 词：DS⁃CDMA 下行链路 多用户 信号子空间 扩频波形估计 Givens旋转 

分 类 号：TN911.23-34[电子电信—通信与信息系统]