大规模MIMO信道估计与预编码技术研究
发布时间：2018-09-01 19:47
【摘要】：随着无线移动设备和服务的迅猛发展,电信运营商面临着对更高数据速率、更大网络容量、更高频谱效率、更高能量效率以及新无线应用所需的更高移动性的持续增长的需求。4G网络已经接近了数据速率的理论极限,难以满足上述挑战,未来第五代(5G)网络技术应运而生。大规模MIMO技术已经受到广泛的关注和深入的研究,成为5G的关键技术之一。在采用频率复用的多蜂窝小区环境下,由于导频污染而产生的上行信道状态信息(CSI)的误差将影响预编码器的性能,这明显地限制了大规模MIMO系统的总速率。此外通过增长天线数量来减小干扰的方法,在导频污染引起的小区间干扰和小区内干扰失效。因此,导频污染是大规模MIMO系统的基本挑战。本文主要对信道估计与预编码技术进行研究。首先概述了5G通信技术,分别介绍了5G特性、关键技术及挑战,并且对大规模MIMO技术的信道估计、预编码和导频污染等方面文献进行了回顾。其次,针对MIMO-OFDM传输方案,研究了一种改进的、通过训练序列中插入零导频符号的信道估计导频图案。对该方的研究表明,所研究的导频图案既有利于减轻导频污染的影响,又便于实现导频复用。最后,我们对一种大规模MIMO下的匹配滤波器(MF)预编码进行了仿真研究。通过对含有多个干扰小区(即含有导频污染)的上行通信链路进行最小二乘法(LS)信道估计,从而得到上行信道的信道矩阵;下行利用已知的信道矩阵进行线性预编码。这里评估了下行的误比特率(BER)。分析和仿真结果表明,在下行发射天线与接收天线比大于10以上时,在基站(BS)端采用简单的线性预编码也可满足一定的误码性能。
[Abstract]:With the rapid development of wireless mobile devices and services, telecom operators are facing higher data rate, larger network capacity and higher spectrum efficiency. The growing demand for higher energy efficiency and higher mobility for new wireless applications. 4G networks have come close to the theoretical limits of data rates and are difficult to meet the above challenges. The fifth generation (5G) network technology emerges as the times require in the future. Large-scale MIMO technology has received extensive attention and in-depth research, and has become one of the key technologies of 5 G. The error of uplink channel state information (CSI) caused by pilot pollution will affect the performance of the precoder in the multi-cell environment with frequency multiplexing, which obviously limits the total rate of large-scale MIMO system. In addition, by increasing the number of antennas to reduce the interference, the inter-cell interference caused by pilot pollution and intra-cell interference failure. Therefore, pilot pollution is a basic challenge for large scale MIMO systems. In this paper, channel estimation and precoding techniques are studied. Firstly, the 5G communication technology is summarized, and the 5G characteristics, key technologies and challenges are introduced, and the literatures on channel estimation, precoding and pilot pollution of large-scale MIMO are reviewed. Secondly, for the MIMO-OFDM transmission scheme, an improved channel estimation pilot pattern based on the insertion of zero pilot symbols in the training sequence is studied. The results show that the pilot pattern can not only reduce the influence of pilot pollution, but also facilitate the realization of pilot multiplexing. Finally, we simulate the (MF) precoding of a large scale MIMO filter. The channel matrix of uplink channel is obtained by least square (LS) channel estimation for uplink communication links with multiple interference cells (that is, with pilot pollution), and linear precoding is performed by using known channel matrix in downlink. BER (BER). For downlink is evaluated here The analysis and simulation results show that when the ratio of the downlink transmit antenna to the receiving antenna is more than 10, the simple linear precoding at the (BS) end of the base station can also satisfy the performance of error code.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN919.3
本文编号：2218167
[Abstract]:With the rapid development of wireless mobile devices and services, telecom operators are facing higher data rate, larger network capacity and higher spectrum efficiency. The growing demand for higher energy efficiency and higher mobility for new wireless applications. 4G networks have come close to the theoretical limits of data rates and are difficult to meet the above challenges. The fifth generation (5G) network technology emerges as the times require in the future. Large-scale MIMO technology has received extensive attention and in-depth research, and has become one of the key technologies of 5 G. The error of uplink channel state information (CSI) caused by pilot pollution will affect the performance of the precoder in the multi-cell environment with frequency multiplexing, which obviously limits the total rate of large-scale MIMO system. In addition, by increasing the number of antennas to reduce the interference, the inter-cell interference caused by pilot pollution and intra-cell interference failure. Therefore, pilot pollution is a basic challenge for large scale MIMO systems. In this paper, channel estimation and precoding techniques are studied. Firstly, the 5G communication technology is summarized, and the 5G characteristics, key technologies and challenges are introduced, and the literatures on channel estimation, precoding and pilot pollution of large-scale MIMO are reviewed. Secondly, for the MIMO-OFDM transmission scheme, an improved channel estimation pilot pattern based on the insertion of zero pilot symbols in the training sequence is studied. The results show that the pilot pattern can not only reduce the influence of pilot pollution, but also facilitate the realization of pilot multiplexing. Finally, we simulate the (MF) precoding of a large scale MIMO filter. The channel matrix of uplink channel is obtained by least square (LS) channel estimation for uplink communication links with multiple interference cells (that is, with pilot pollution), and linear precoding is performed by using known channel matrix in downlink. BER (BER). For downlink is evaluated here The analysis and simulation results show that when the ratio of the downlink transmit antenna to the receiving antenna is more than 10, the simple linear precoding at the (BS) end of the base station can also satisfy the performance of error code.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN919.3
【参考文献】
相关硕士学位论文 前1条
1 方娜燕;面向5G的下行多天线传输关键技术研究[D];电子科技大学;2014年
，本文编号：2218167
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