论文标题:用于色散CDMA系统盲信号检测和盲信道估计的子空间新方法的研究
Research of new Subspace-based method of blind multiuser detection and channel estimation in Dispersive CDMA Channels
论文作者 吴涛
论文导师 戴宪华,论文学位 硕士,论文专业 信号与信息处理
论文单位 汕头大学,点击次数 86,论文页数 55页File Size1737k
2001-07-01论文网 http://www.lw23.com/lunwen_10028407/ 多输入多输出,多用户检测,色散信道,盲源分离,码分多址,符号间干扰,多址干扰,签名波形
MIMO, Multiuser detection, dispersive, BSS, CDMA, ISI, MAT, signature waveform
子空间的高分辨率的方法在盲多用户检测，传感器阵列信号处理，谱分析和普通的参数估计中扮演一个重要的角色。随着码分多址系统的码速率的提高，符号间干扰将和多址干扰一起成为高速码分多址系统的固有问题，成为影响整个系统性能的主要妨碍。 本文首先针对短ISI的情况，提出了用改进的子空间算法对签名波形进行盲估计，这其中包括一个信号子空间的方法和一个噪声子空间的方法。并重点讨论了用户的扩频码之间的正交性对多径信道估计的影响。其次针对有色噪声的码分多址色散信道，提出了一种使用短训练序列的波形估计的子空间算法。最后，我们在考虑长符号间干扰的信道情况下，把色散码分多址系统归入一个多输入多输出系统的框架，通过应用盲多输入多输出理论，提出了使用期望用户的签名波形的子空间信号检测算法。可以看到通过上面提出的算法可以实现各种情况下的码分多址系统的盲检测。
Subspace梑ased high梤esolution methods play an important role in sensor array processing, spectrum analysis, and general parameter estimation. With the improve of chip梥peed in high? rate CDMA system, the 151 together MAT become the inherent problem and constituted the major impediment to the overall system performance. In this paper, firstly, to the case of short 151, It is discussed that modified algorithms are used to estimate the response of channel or signature blindly, which includes a signal subspace method or a noise subspace method, the affection of the nonorthogonality of signature in the estimation of response of multi梡ath channel. Secondly ,an algorithm of subspace training method to signature waveform estimation in multipath CDMA channel with colored noise is proposed. Finally, to do with the case of long JSI ,we cast the dispersive CDMA channel into a MJMO signal model framework. By applying the theory of blind MIMO channel identification and the desired user抯 signature waveform, we propose a subspace? based method of estimation of response of channel or signal detection. It is seen that we can perform signal detection blindly at any case of CDMA system.
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