TD-LTE系统下行链路多流波束赋形技术的研究

发布时间：2018-01-22 01:33

本文关键词： 长期演进物理下行共享信道波束赋形信道估计　出处：《武汉邮电科学研究院》2014年硕士论文　论文类型：学位论文

【摘要】：本文对于TD-LTE系统中波束赋形的相关技术进行了分析及研究，并给出了相应的仿真结果。本文首先针对TD-LTE物理层特性，例如无线帧结构，物理层各个信道与参考信号以及OFDM技术进行了概述。因为本文的波束赋形相关内容是在下行共享信道上加以实现的，因此对下行共享信道的关键技术进行了相关介绍，重点介绍了MIMO的三种方案，分别是发射分集，空分复用以及波束赋形。本文在第四章分别从单用户波束赋形以及多用户波束赋形的角度着重分析了波束赋形过程中的相关技术，，包括基站侧计算波束赋形权向量的算法以及在UE侧的相关检测算法。关于基站侧波束赋形权向量的获取方法，重点分析了单用户波束赋形中现有的获取波束赋形权向量的方案，并针对现有方案的缺点提出了一种新的获取波束赋形权向量的方法。关于UE侧的相关检测算法，重点分析了信道估计算法，即在波束赋形方案下用DM-RS作为导频信号传输的情况下，如何获取导频点处的信道系数，以及通过各种插值算法获取整个频域方向的信道系数。在频域插值算法的推导中，针对下行DM-RS的分布在连续PRB上来看并不是等间隔分布的特点，对频域插值算法中的DFT变换域插值算法进行改进，并在第五章仿真结果分析中对改进的算法进行了验证。
[Abstract]:In this paper, the related techniques of beamforming in TD-LTE system are analyzed and studied, and the corresponding simulation results are given. This paper first focuses on the physical layer characteristics of TD-LTE, such as wireless frame structure. The physical layer of each channel and reference signal and OFDM technology are summarized, because the beamforming related content in this paper is implemented on the downlink shared channel. Therefore, the key technologies of the downlink shared channel are introduced, and the three schemes of MIMO, namely transmit diversity, space-division multiplexing and beamforming, are emphatically introduced. In chapter 4th, we analyze the technology of beamforming from the angle of single user beamforming and multiuser beamforming. The algorithm of calculating beamforming weight vector on base station side and correlation detection algorithm on UE side are included. Regarding the method of obtaining the weight vector of the side beam of the base station, the existing scheme of obtaining the weight vector of the beam shape in the single user beamforming is analyzed emphatically. A new method to obtain beamforming weight vector is proposed to overcome the shortcomings of the existing scheme. For the correlation detection algorithm of UE side, the channel estimation algorithm is mainly analyzed, that is, how to obtain the channel coefficient at pilot point when DM-RS is used as pilot signal transmission under beamforming scheme. In the derivation of frequency-domain interpolation algorithm, the distribution of downlink DM-RS on continuous PRB is not equal-interval distribution. The DFT transform domain interpolation algorithm in frequency domain interpolation algorithm is improved, and the improved algorithm is verified in the analysis of simulation results in Chapter 5th.
【学位授予单位】：武汉邮电科学研究院
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.5

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