迅速推广T D-LT E-A为全球信息消费服务的战略思考

2014年全球TD-LTE与LTE FDD的进展都很迅速，二者比较起来，TD-LTE的增长更快，特别是用户以高7倍的速率猛涨。预期一两年内TD-LTE将迅速追上LTE FDD成为4G的主流。2015年TD-LTE的国内发展规划宏伟，基站100万个，用户2.5亿户，将向LTE-A演进，数据速率将提升至1Gbps。TD-LTE应乘“一带一路”东风首先开拓“丝绸之路经济带”逐步走向全球。4G的杀手锏应用是3D，4G+3D有10万亿元的市场规模，是振兴中华的最佳途径。我国应以国际视野取代民族视野，以宽阔胸襟树立国际化形象，这样才能迅速走向世界为全球的信息消费服务。     

LTE TDD与FDD共站建设方案分析

主要从LTE TDD与FDD的技术差异、建站模式、设备方案和供电方式几个方面来分析,探讨TDD与FDD共站建设方案。在快速建站、节约材料的基础上,分析TDD与FDD共站的可行性和优势,提出了TDD(时分双工)和FDD(频分双工)组网建设方案的建议,符合节能绿色通信的时代潮流。     

TD—SCDMA演进与国内TD产业发展形势分析

文章首先阐述了TD—SCDMA在国内的发展现状,然后论述了LTE和TD-LTE的特点,指出了从TD—SCDMA到TD-LTE的发展将面临较长的窗口期,以及中国TD产业面临机遇和挑战。     

UMTS MIMO技术标准演进研究

讨论了UMTS移动通信中的多天线——MIMO技术,介绍了空间分集、空间复用与MIMO的概念与分类、基于空间分集的空时码与基于空间复用的分层空时码,详细研究了3GPP UMTS标准演进中的FDD与TDD MIMO方案。     

Outage analysis of ANC in the FDD two-way fading channel with channel estimation error

This paper considers a frequency-division duplex (FDD) two-way channel with channel estimation error, where channel gains are independent of each other. It derives the exact closed-form outage probability expressions in the FDD system with analog network coding (ANC) by use of probability theory. To provide more insights, an approximated version for the exact outage probability is also developed in the medium-to-high signal-to-noise ratio (SNR) region. The simulation results show that the derived exact outage probabilities match the results of Monte Carlo simulations in all SNR regions, while the approximated outage probabilities also approach the simulation results when the channel condition is good. It is interesting that ANC in the FDD two-way channel is proved to outperform that of in the time-division duplex (TDD) channel by the computer simulation.     

TD-SCDMA技术优势与演进策略

介绍第三代移动通信中TDD系统的特点 ,比较了两种TDD技术的异同 ,分析了TD -SCDMA制式的技术与经济优势     

Effects and optimization of pilot sequence length on rate in multiuser massive MIMO FDD system

The effect of pilot sequence length on the asymptotic performance of the ergodic rate was investigated for the multiuser massive multiple-input multiple-output (MIMO) frequency division duplexing (FDD) downlink system.Firstly,the analytical expression of the ergodic rate was derived by using the principle of deterministic equivalence,based on which,it was discovered from the analytical results in two-fold that the normalized pilot sequence length (defined as the pilot sequence length divided by the number of BS antennas) tends to zero yet the rate was guaranteed to grow large without limit as long as the BS antenna number continues to increase,the rate saturates to a certain level if the BS antenna number becomes large with fixed pilot sequence length.Moreover,the pilot sequence length was optimized based on the sum-rate maximization within a finite channel coherence time,and a closed-form solution was deduced under a special correlated channel by means of Lambert W function.Simulation results validate the correctness of the theoretical analysis results and verify the effectiveness of the proposed closed-form solution of the optimal pilot sequence length.     

基片集成波导全向滤波天线多天线阵列

设计、制作并测量了工作在Ku波段的、可用于频分复用(FDD)无线通信系统的基片集成波导缝隙辐射全向滤波天线及其多输入多输出(MIMO)天线阵列。滤波天线是将射频滤波器和天线辐射部分进行一体化、联合设计,以减少射频前端滤波器与天线间的连接所引入的插入损耗。经过仿真、制作、测量和比较,得出结论:独立全向滤波天线保持了辐射部分的全向辐射特性,同时能很好地抑制带外杂散信号,使输入端反射系数的过渡带变得陡峭。工作在13.6GHz和14.4GHz、带宽为100MHz的相邻频率的全向滤波天线隔离性能良好,可用于频分复用系统的收、发信道。多输入多输出天线阵列中的单个全向滤波天线辐射特性基本保持不变。     

一种用于MlMO系统的双码本预编码方法

时分复用(TDD)模式的通信系统可以通过有效利用信道的互易性,即通过上行链路对下行信道信息进行估计,并利用估计得到的信息对MIMO通信系统进行预处理或者预编码,从而进一步提升MIMO系统的信道容量和性能。然而,对于频分复用(FDD)的通信系统,由于上下行频段的不对称使得信道互易性原则不再适用,此时欲对信道进行预处理,则必须通过终端对下行信道信息进行上行反馈。反馈方式可分为直接对下行信道信息进行量化反馈的显式反馈和将量化后的信道空间以码本形式进行反馈的隐式反馈。对信道空间量化的隐式反馈进行研究,并在此基础上提出了一种双码本预编码的方法,并进一步对所提方案进行了理论分析和仿真验证。     

LTE全球主流运营商及产业链发展动态

本文以全球化的发展眼光,从网络部署建设,网络发展运营和产业链的角度,对全球LTE商用情况,主流运营商发展现状与发展策略,终端发展情况进行跟踪与分析,全面阐述LTE的发展现状与未来发展前景.