摘要
针对低信噪比(SNR)下存在多径效应的传统单通道异步长码直接序列码分多址(DS-CDMA)信号伪码序列(PN)及信息序列难估计问题,该文提出一种基于平行因子的多通道盲估计方法。该方法先将接收到的多径信号建模为多通道模型,然后将长码DS-CDMA信号建模成短码DS-CDMA信号的缺失数据模型,形成观测缺失数据矩阵,并将其等效为缺失平行因子模型,最后利用正则交替最小二乘法(ALS)对缺失平行因子进行低秩分解,实现多径环境下长码DS-CDMA信号各用户伪码序列及信息序列的盲估计。仿真结果表明,序列的估计性能与多径环境密切相关,且在莱斯因子为10,多径路数为3,通道数为4,用户数为6,信噪比大于–10 dB的条件下,伪码序列及信息序列的估计错误率均低于1%。
For the problem of long code Direct Sequence-Code Division Multiple Access(DS-CDMA)signal in traditional asynchronous single-channel with multipath effect under low Signal-to-Noise Ratio(SNR),including blind estimation of the Pseudo-Noise(PN)sequence and information sequence,a method using multi-channel synchronous and asynchronous based on parallel factor is proposed.Firstly,the received signal in multipath environment is modeled as a multi-channel receiving model.And then the long code DS-CDMA signal is modeled as the short code DS-CDMA signal with missing data to form the observation missing-data matrix,which is equivalent to a parallel factor model with missing data.Finally,the regularized Alternating Least Squares(ALS)algorithm is applied to decompose the parallel factor,and the PN sequence and information sequence of long code DS-CDMA signals in multipath environment can be further estimated.Simulation results show that the performance of sequences estimation closely relates with the multipath environment,and the estimation error rate of 6 user PN sequences and information sequence is less than 1%under the condition that the Rician factor is equal to 10 and the number of path and channel are 3 and 4 respectively when the SNR is higher than-10 dB.
作者
周杨
张天骐
ZHOU Yang;ZHANG Tianqi(Chongqing Key Laboratory of Signal and Information Processing,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)
出处
《电子与信息学报》
EI
CSCD
北大核心
2021年第4期1137-1144,共8页
Journal of Electronics & Information Technology
基金
国家自然科学基金(61671095,61371164)
信号与信息处理重庆市市级重点实验室建设项目(CSTC2009CA2003)
重庆市杰出青年基金(CSTC2011jjjq40002)。
关键词
长码直接序列码分多址信号
缺失数据模型
多径环境
伪码序列
信息序列
Long code Direct Sequence-Code Division Multiple Access(DS-CDMA)signal
Missing-data model
Multipath environment
Pseudo Noise(PN)sequence
Information sequence
作者简介
通信作者:周杨:男,1989年生,博士,主要研究方向为通信信号的盲处理.zhouyang@cqupt.edu.cn;张天骐:男,1971年生,博士后,教授,主要研究方向为通信信号的调制解调、盲处理、语音信号处理、神经网络实现以及FPGA实现.
