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Hybrid CSI-RS Transmission Mechanism-Based 3D Beamforming Scheme for FDD Massive MIMO System 被引量:1
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作者 Fangchao Zhang Shaohui Sun +1 位作者 Qiubin Gao Hui Li 《China Communications》 SCIE CSCD 2016年第S2期109-119,共11页
Massive multiple-input multipleoutput(MIMO) refers to the idea that equipping base station(BS) with a large number of antenna elements,and features the ability of three dimensional(3D) beamforming technique to enable ... Massive multiple-input multipleoutput(MIMO) refers to the idea that equipping base station(BS) with a large number of antenna elements,and features the ability of three dimensional(3D) beamforming technique to enable improvement in system performance.The prior works on massive MIMO generally rely on a common assumption of the whole channel characteristics are perfectly known at both user equipment(UE) and BS,however,this is quite difficult to realize in practical frequency division duplexing(FDD) system since the channel state information reference signal(CSIRS) overhead and CSI feedback overhead are proportional to the number of antenna elements.In this paper,two hybrid CSI-RS transmission mechanism-based 3D beamforming schemes are proposed in FDD massive MIMO system,in which non-beamformed CSI-RS configuration is utilized in conjunction with beamformed CSIRS configuration.In the proposed schemes,an angle quantization-based vertical codebook and a DFT-based horizontal codebook are designed,respectively,and an eigenvalue decompositionbased precoding matrix indicator(PMI)selection algorithm is also proposed for CSI acquisition.Simulation results show that the proposed 3D beamforming schemes achieve significant improvement in system capacity without incurring excessive CSI-RS overhead. 展开更多
关键词 massive MIMO 3d beamforming csi-rs COdEBOOK FEEdBACK PMI
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Self-Interference Elimination by Physical Feedback Channel in CCFD for 3-D Beamforming Communication
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作者 Naveed Ali Kaimkhani Zhe Chen Fuliang Yin 《China Communications》 SCIE CSCD 2017年第9期62-71,共10页
The 3-D beamforming scheme has elite as evolving interest because of its efficiency to empower assorted techniques such as vertical and horizontal domains and emanation beamforming according to subscriber's provis... The 3-D beamforming scheme has elite as evolving interest because of its efficiency to empower assorted techniques such as vertical and horizontal domains and emanation beamforming according to subscriber's provisions. Usually, 3-D beamforming communication is set up on FDD/TDD approach those effects on the performance of spectrum and energy efficiency. Co-frequency and CoTime Full Duplex(CCFD) is an effective solution to improve the spectrum and energy efficiency by transmitting and receiving simultaneously in frequency and time domain. While, CCFD communication often face the self-interference issue when communication occurs, simultaneously. Consequently, in this paper a self-interference elimination by physical feedback channel in CCFD for 3-D Beamforming communication scheme is proposed to improve the over-all system performance in terms of energy and spectrum efficiency. The simulation and analytical outcomes demonstrated that the proposed system is superior than the traditional one. 展开更多
关键词 spectrum efficiency energy effi-ciency co-frequency and co-time full dUPLEX SELF-INTERFERENCE suppression 3-d beamform-ing
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Digital Beamforming by Multiple Chirp Zeta Transforms for 3-D Sonar Imaging Systems
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作者 袁龙涛 田翔 +1 位作者 韩业强 陈耀武 《Journal of Donghua University(English Edition)》 EI CAS 2012年第5期373-379,共7页
The computational load is prohibitive for real-time image generation in 3-D sonar systems, particularly when the steering angle approximation is required. In this paper, a novel multiple Chirp Zeta Transforms (MCZT) b... The computational load is prohibitive for real-time image generation in 3-D sonar systems, particularly when the steering angle approximation is required. In this paper, a novel multiple Chirp Zeta Transforms (MCZT) beamforming method in frequency domain is being proposed. The single long-length Chirp Zeta Transform (CZT) in the original CZT beamforming is replaced by several CZTs with smaller lengths for different partitions along each dimension. The implementing routine of the algorithm is also optimized. Furthermore, an avenue to evaluate the estimating error for the angle approximation in 3-D imaging applications is presented, and an approach to attain valid partitions for the steering angles is also illustrated. This paper demonstrates a few advantages of the proposed frequency-domain beamforming method over existing methods in terms of the computational complexity. 展开更多
关键词 信号处理 数字信号处理 通信 通信理论
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Interference Coordination for FD-MIMO Cellular Network with D2D Communications Underlaying 被引量:1
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作者 Xiao Li Nana Qin Tingting Sun 《China Communications》 SCIE CSCD 2018年第12期75-88,共14页
In this paper, we investigate the interference coordination for downlink full-dimension multiple-input multiple-output(FD-MIMO) systems with device-to-device(D2 D) communications underlaying. With three-dimensional(3 ... In this paper, we investigate the interference coordination for downlink full-dimension multiple-input multiple-output(FD-MIMO) systems with device-to-device(D2 D) communications underlaying. With three-dimensional(3 D) beamforming transmission applied for cellular users(CUEs), an approximation of the interference to signal ratio for CUEs is derived, and a coordination strategy is proposed to mitigate the interference from D2 D pairs to CUEs. Based on the lower bound of the interference to signal ratio for D2 D pairs, we propose coordination strategies for D2 D pairs to mitigate the interference caused by base station(BS) and the interference between D2 D pairs. The proposed strategies require only some statistical channel state information(CSI) of each user and the reduced-dimensional effective CSI of a few CUEs and D2 D pairs. Simulation results show that the proposed coordination strategy performs well in terms of achieving good tradeoff between the achievable rate of CUEs and D2 D pairs. 展开更多
关键词 d2d Fd-MIMO 3d beamforming interference COORdINATION
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Non-Statistical Multi-Beamformer 被引量:1
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作者 Nuri Yilmazer Wonsuk Choi +1 位作者 Tapan Sarkar Sunmeel Bhumkar 《Journal of Signal and Information Processing》 2012年第1期26-29,共4页
In this paper, a multiple beamforming technique is presented by using a direct data domain least squares (D3LS) approach. Direct data domain approach is very suitable for real time applications since it utilizes only ... In this paper, a multiple beamforming technique is presented by using a direct data domain least squares (D3LS) approach. Direct data domain approach is very suitable for real time applications since it utilizes only a single snapshot of data as opposed to statistical approaches where multiple measurements have to be taken and the covariance matrix has to be formed. It is also very effective especially in the case of blinking jammers where the statistical approaches will fail or needs to perform additional tasks to overcome it. It has been previously shown that the D3LS can successfully handle only one or two Signal of Interests (SOI). Here, we have developed a new technique where multiple SOI can be handled simultaneously. Numerical simulations have shown that the new approach can maximize the signals from the direction of the SOI at the same time minimizing the jammers. The new approach can be successfully applied in the satellite communications, Over the Horizon Radars (OTHR) as well as wireless communications to detect or track multiple targets simultaneously. 展开更多
关键词 beamforming Multiple beamforming dIRECT data dOMAIN Approach d3LS Efficient beamforming Single SNAPSHOT
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基于信道状态信息参考信号的三维多用户多输入多输出有限反馈预编码算法
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作者 王华华 周远文 黄龙 《科学技术与工程》 北大核心 2018年第12期115-119,共5页
利用三维多输入多输出(3D MIMO)信道矩阵的克罗内克积结构,传输预编码可分成水平与垂直维预编码,有效挖掘空间自由度可以提高系统性能。针对现有算法未能更好利用空间自由度及单流传输的不足,提出了一种基于信道状态信息参考信号(CSI-RS... 利用三维多输入多输出(3D MIMO)信道矩阵的克罗内克积结构,传输预编码可分成水平与垂直维预编码,有效挖掘空间自由度可以提高系统性能。针对现有算法未能更好利用空间自由度及单流传输的不足,提出了一种基于信道状态信息参考信号(CSI-RS)的多用户MIMO(MU-MIMO)有限反馈预编码算法。该算法采用新码本,依据最大信干噪比准则选取最优的预编码矩阵索引(PMI)返回给基站(BS)供调度。验证结果显示该算法较已有算法,实现了多流传输,拥有更优的和速率(SR)及误码率(BER)。 展开更多
关键词 3d MIM0 csi-rs 多用户 多流传输 预编码
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基于分级波束形成的三维声纳系统设计 被引量:3
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作者 林贤洲 陈耀武 《传感器与微系统》 CSCD 北大核心 2014年第8期101-104,108,共5页
针对三维声纳波束形成海量运算造成硬件系统复杂难以实现的问题,设计了基于分级波束形成的三维声纳系统。系统基于大规模(48×48)换能器接收基阵,采用分布式现场可编程门阵列(FPGA)结构实现两级波束形成,所需计算量相比传统波束形... 针对三维声纳波束形成海量运算造成硬件系统复杂难以实现的问题,设计了基于分级波束形成的三维声纳系统。系统基于大规模(48×48)换能器接收基阵,采用分布式现场可编程门阵列(FPGA)结构实现两级波束形成,所需计算量相比传统波束形成减少九成。该算法经Matlab仿真验证了其合理性,系统样机经水下试验证明:在水平50°垂直50°覆盖角的观测范围内,实现角度分辨率达到0.39°,距离分辨率达到2cm的三维成像。 展开更多
关键词 三维声纳 换能器 分级波束形成 海量运算 现场可编程门阵列
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随机误差及串扰对三维成像声纳的影响
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作者 于涤非 张春华 张武 《网络新媒体技术》 2017年第6期27-34,共8页
为评估硬件系统引入的误差对三维声纳成像效果的影响,分析存在随机误差(包括幅相误差、阵元失效)时,主瓣宽度、旁瓣高度、阵增益、波束指向误差的均值并给出样本分布,推导存在串扰时的波束形成公式及分析其影响。通过仿真分析,其结果表... 为评估硬件系统引入的误差对三维声纳成像效果的影响,分析存在随机误差(包括幅相误差、阵元失效)时,主瓣宽度、旁瓣高度、阵增益、波束指向误差的均值并给出样本分布,推导存在串扰时的波束形成公式及分析其影响。通过仿真分析,其结果表明,随机误差对阵增益及成像信噪比影响较大,对主瓣宽度及波束指向精度影响较小。阵增益随随机误差的增大而显著降低,旁瓣高度均值随着随机误差的增大而显著增加,导致三维声纳成像信噪比降低。串扰对测向精度影响较小,对目标强度的测量精度产生较大影响,导致三维声纳成像的对比度会产生失真。 展开更多
关键词 水声学 三维成像声纳 波束形成 幅相误差 阵元失效 串扰
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阵元数对组合线阵近场目标定位性能的影响
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作者 李昆鹏 康春玉 +2 位作者 夏志军 张闻龙 张亿 《舰船电子工程》 2019年第11期51-55,69,共6页
针对近场水下目标被动定位问题,提出了组合线阵的设计构想,推导出了基阵数据接收模型和近场三维声聚焦波束形成方法,将三维空间切割为多个扫描球面,通过对切割球面上聚焦点的扫描,得到目标方位角和俯仰角,再通过对不同扫描球面上最大输... 针对近场水下目标被动定位问题,提出了组合线阵的设计构想,推导出了基阵数据接收模型和近场三维声聚焦波束形成方法,将三维空间切割为多个扫描球面,通过对切割球面上聚焦点的扫描,得到目标方位角和俯仰角,再通过对不同扫描球面上最大输出功率的比较实现目标距离估计。采用常规波束形成方法仿真分析了组合线阵阵元数对水下目标三维空间被动定位性能的影响,结果表明,阵元数越多,阵增益就越强,目标定位的性能就越好,因此,组合线阵设计时每条子阵上的阵元数应尽可能多。 展开更多
关键词 组合线阵 常规聚焦波束形成 三维空间被动定位
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基于自适应算法的三维波束赋形技术 被引量:1
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作者 赵季红 王伟华 曲桦 《北京邮电大学学报》 EI CAS CSCD 北大核心 2014年第4期88-92,共5页
针对每个移动终端进行动态的三维波束赋形,为了使三维波束主瓣对准期望用户并且在干扰用户方向形成零陷,构建了均匀平面阵的二维阵列信号模型,研究了基于最小均方误差算法的全局自适应算法,并在此基础上提出了基于降维的局部自适应算法.... 针对每个移动终端进行动态的三维波束赋形,为了使三维波束主瓣对准期望用户并且在干扰用户方向形成零陷,构建了均匀平面阵的二维阵列信号模型,研究了基于最小均方误差算法的全局自适应算法,并在此基础上提出了基于降维的局部自适应算法.2种自适应三维波束赋形算法可以动态地调整阵列单元的权值,自适应地改变天线阵列的方向图,为用户提供实时的跟踪服务.仿真结果表明,在一定数量的阵列天线单元的条件下,2种算法均可以实现针对期望用户的自适应三维波束赋形. 展开更多
关键词 均匀平面阵 自适应算法 三维波束赋形
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