智能天线在未来移动通信系统中的发展动态

智能天线是近年来移动通信领域中的一个研究热点，是解决频率资源匮乏的有效途径，同时还可以提高系统容量和通信质量，智能天线利用数字信号处理技术。产生空间定向波束，使天线主波束对准用户信号到达方向，旁瓣对准干扰信号到达方向，以达到充分高效利用移动用户信号并消除或抑制干扰信号的目的。智能天线是一个具有良好应用前景且尚未得到充分开发的新技术，是3G移动通信系统中不可或缺的关键技术之一。     

TD-SCDMA中的关键技术——智能天线

由我国提交的第三代移动通信标准TD-SCDMA系统的关键技术之一就是智能天线技术,本文介绍了智能天线的提出及其分类,并且根据其优点深入分析了该技术在TD-SCDMA中的运用。     

基于智能天线的层次化CDMA移动通信网络设计

本文通过使用智能天线,给出高性能的层次化CDMA移动通信网络的设计策略。重点是对大区到小区所需的功率分析,大区智能天线模式分析以及小区天线倾斜角度对系统性能提高的影响。结论表明系统性能取决与小区位置和天线倾斜角度。通过定义干扰平衡因子得到最优的小区天线倾斜角度。     

WCDMA系统智能天线通道不一致性在线校正方法

研究智能天线通道不一致性的注入校正方法。基于WCDMA移动通信系统智能天线通道的物理层协议标准,提出一种新的注入校正方法。该方法首先采用搜索器估计通道的复增益,然后利用复增益的估计值实现通道不一致性的校正。理论分析和Matlab仿真表明,该注入校正方法能使智能天线的性能得以改善。     

浅谈移动通信中的智能天线技术及应用实例

本文浅述了移动通信中传统天线的局限性、多波束智能天线的基本情况、自适应天线阵、智能天线的发展概况及智能天线的应用实例,并筒述了它们在日常维护和网络优化中的作用。     

手持式天线姿态检测仪表在通信网络优化的实现和应用

在移动通信系统中,天线的位置和姿态直接影响覆盖区域、网络质量和用户感知.本文提出一种基于智能磁方位传感器实现天线姿态的自动采集系统,并创新性的设计成手持式仪表,使该系统同时具备精确测量与便携灵活的特点,实现了天线姿态信息从人工机械测量向自动精确测量的飞跃.     

浅析智能天线在移动通信中的应用与发展前景

智能天线被公认为是未来移动通信的一种发展趋势.文章对天线的基本概念、关键技术、系统性能的改善及国外研究状况等进行了阐述,指出了研究过程中存在的问题及发展方向.     

4G概念移动通信关键技术浅析

本文对3G和4G移动通信做了简要的比较,并对4G移动通信系统中将会用到的关键技术做了分析。包括OFDM技术、智能天线技术、软件无线电技术、多用户检测技术、IPv6技术等。     

智能天线技术与第三代移动通信系统

首先对移动通信的发展、第三代移动通信系统的主要目标以及IMT－2000的无线传输技术方案做了简要叙述,然后讨论了第三代移动通信中的关键之一智能天线技术的基本概念。着重描述了时空信道模型和时空信道估计,最后简要介绍了多用户下行选择性发送的实现方法。     

浅议智能天线在移动通信网中的应用

智能天线是一个天线阵列.它由多个天线单元组成,可以形成多个不同方向的波束,其基本思想是通过天线阵列及时空信号处理技术,提取各移动用户的空间方位信息,利用用户位置的不同,减少干扰提高移动通信的传输质量及系统容量,在CDMA网中的应用具有特别重要的意义.     

双极化天线MIMO中SAST编码性能分析

为解决单极化天线中多输入多输出（MIMO）技术与移动终端有限体积之间的矛盾,将半正交代数空时（SAST）编码应用到配置双极化天线的MIMO系统中,并对SAST编码性能进行理论分析。将置换矩阵和交叉极化鉴别度（XPD）转换为等效信道的一部分,并使SAST编码在双极化天线中的传输模型等效转变为该编码在单极化天线中的传输模型,根据秩准则和乘积准则分析置换矩阵不同时,XPD对分集增益和编码增益的影响,并给出相应的译码方法。仿真结果验证了该理论分析的正确性。     

Compact wideband MIMO mobile‐antenna system design using mode‐based decoupling techniques

This work focuses on designing small mobile antennas and their multiple‐input multiple‐output (MIMO) applications. In this study, it was investigated that small mobile antennas can obtain high radiation performance only when a tight coupling with the ground plane is generated through ground‐mode tuning (GMT) of the ground plane. Furthermore, a novel mode‐based decoupling concept is presented for their MIMO applications, based on a four‐port network and by considering the ground‐mode effect. Consequently, the proposed mode‐based decouplers can effectively sustain high radiation performance and improve the isolation while providing low correlation by generating diagonally directed radiation patterns. In the proposed MIMO system, both GMT structures and mode‐based decouplers are implemented utilizing the metal rims around the ground plane, thereby occupying very compact clearance, and the measured MIMO antennas fully covered 0.69 to 1 GHz band with high isolation up to 20 dB and low envelope correlation coefficient (ECC) value below 0.5, sufficiently applicable in mobile devices.     

移动卫星天线的自适应鲁棒控制系统

为了改善移动卫星天线的控制性能和稳定性,本文进行移动卫星天线的自适应鲁棒控制系统的研究．首先针对移动卫星天线数学模型,设计自适应鲁棒控制器和控制系统,所提出的自适应鲁棒控制律和控制系统不仅保证了闭环系统的稳定性,而且实现了所期望的性能,最后通过试验结果证明该控制算法的有效性,尽管外界环境道路条件的变化不同,移动卫星天线控制系统表现了满意的控制性能．     

基于OFDM定时捕获的分布式天线位置设计

在线形小区中,基站的两分布式接收天线接收来自单天线移动台的发射信号.基于OFDM定时捕获,提出利用最小最大准则进行线形小区中两分布式天线的最优位置设计.根据最小最大准则,最优天线位置根据最坏捕获情况最小化得到.仿真结果表明,当移动台位置在线形小区中均匀分布时,两分布式接收天线应根据线形小区中心对称放置.     

Performance of Dual-Polarized DSTTD-IDMA system over correlated frequency selective channels

In this correspondence, we present the performance of Dual-Polarized double space–time transmit diversity (DSTTD) aided multiple-input multiple-output (MIMO) interleave division multiple access (IDMA) scheme over correlated frequency-selective channels for downlink communication. DSTTD system is realized by employing two space–time block code units at the base station (BS). We employ two Dual-Polarized antennas both at the BS and mobile stations. We consider maximum-likelihood ratio detection algorithm at the receiver to detect the signals and to mitigate the effects of multiple access interference and multi stream interference. We implement iterative type turbo decoding algorithm to enhance bit error rate (BER) performance. We evaluate the performance of Dual-Polarized DSTTD-IDMA system based on Stanford University Interim channel models and Long-Term Evaluation channel model. Our simulation results reveal that DSTTD-IDMA system with Dual-Polarized antenna requires higher SNR than uni-polarized antennas. However, it provides the advantage of replacing two uni-polarized antennas by a single Dual-Polarized antenna.     

Cost effective Android-Antenna Tool (AAT) for the parameter calculation of antenna in android platform

Mobile technology evolution and mobile based education are highly needed for academic system. Especially designing a physical antenna is a tough task so that Simulation solution has been used in the laboratory. Even though it is costlier and it could be used only in LAN based computers for an academic purpose but not used in outside. To be clear, the designing of an antenna with institution studies are needed. To overcome and achieve the objective of the paper which proposes to develop a mobile based designing antennas such as Dipole, Loop antennas. The performances of antenna have been carried out in mobile platform. This is an attempt to predict parameters of specified antenna in the android platform. Through this application the students could able to predetermine the characteristic of specified antenna easily. This application will be highly useful and recommended to the students. The proposed work has been designed by Eclipse software and Android studio software. Finally the performance of the antenna parameters has been carried with the help of Android-Antenna Tool (AAT).     

Small‐size four‐element antenna system for 2 × 2 LTE LB and 4 × 4 LTE M/HB MIMO operations in 5G mobile terminals

A small‐size four‐element antenna system for 2 × 2 LTE low band (LB, 698‐960 MHz) and 4 × 4 LTE middle/high band (M/HB, 1710‐2690 MHz) multiple‐input multiple‐output (MIMO) operations in 5G (fifth‐generation) mobile terminals is presented. The proposed antenna system is formed by two identical tunable loop antennas and two identical coupled‐fed IFA (Inverted‐F Antenna) antennas. By loading a RF switch with four output states as tunable component, the proposed loop antenna can not only operate in the M/HB, but also achieve improved bandwidth coverage in the LB. Each coupled‐fed IFA element operating in the M/HB with compact volume. The four antennas are placed on the both short side‐edge of the mobile terminal with small ground clearance of 4.2 mm. The simulated S‐parameters show that the proposed MIMO system can cover 698 to 960 MHz and 1710 to 2690 MHz with reflection coefficients less than ?6 dB and isolations are all more than 12 dB. Good MIMO performances such as radiation efficiencies, envelope correlation coefficient (less than 0.4 within the entire operation bands) and channel capacity are also obtained. The effects of user's hand(s) on performances for the proposed antenna system are also discussed. This four‐element antenna system prototype is fabricated and measured.     

发射分集MC-CDMA系统空时多用户检测

该文研究了在频率选择性瑞利衰落信道中的同步多载波码分多址(MC-CDMA)系统上行链路,在移动终端处使用两个发射天线,采用基于空时分组码的发射分集,基站采用分集天线接收。考虑对应于子载波的衰落系数是信道冲激响应的离散傅里叶变换,给出了采用发射分集和接收分集的MC-CDMA系统上行链路信号模型。研究了采用发射分集和接收分集的MC-CDMA系统的解相关多用户检测、最小均方误差(MMSE)多用户检测,进行联合的多用户检测和空时码解码。仿真结果验证了上述模型及算法的有效性。     

移动电视智能天线自适应算法综述

首先介绍了智能天线的基本概念和分类,随后着重介绍了三种自适应算法。继而描述了将智能天线用于车载高清晰数字电视的研究,最后提出了智能天线有待研究的课题。     

手机PCB天线的设计思考

天线是手机的重要装置,直接影响着手机通话质量。该文介绍手机PCB天线的基本结构特性,微带天线的优点及手机PCB天线在设计时应考虑的问题和设计思路：