检索结果-内蒙古大学图书馆

zero-forcing precoding and generalized inverses

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2008年第9期56卷 4409-4418页

作者： Wiesel, Ami Eldar, Yonina C. Shamai (Shitz), Shlomo Technion Israel Inst Technol IL-32000 Haifa Israel Univ Michigan Coll Engn Dept Elect Engn & Comp Sci Ann Arbor MI 48109 USA

We consider the problem of linear zero-forcing precoding design and discuss its relation to the theory of generalized inverses in linear algebra. Special attention is given to a specific generalized inverse known as the pseudo-inverse. We begin with the standard design under the assumption of a total power constraint and prove that precoders based on the pseudo-inverse are optimal among the generalized inverses in this setting. Then, we proceed to examine individual per-antenna power constraints. In this case, the pseudo-inverse is not necessarily the optimal inverse. In fact, finding the optimal matrix is nontrivial and depends on the specific performance measure. We address two common criteria, fairness and throughput, and show that the optimal generalized inverses may be found using standard convex optimization methods. We demonstrate the improved performance offered by our approach using computer simulations.

关键词： beamforming generalized inverses per-antenna constraints semidefinite relaxation zero-forcing precoding

来源：评论

学校读者我要写书评

暂无评论

Fast Computation of zero-forcing precoding for Massive MIMO-OFDM Systems

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2024年 72卷 912-927页

作者： Liu, Junkai Zhang, Wei Jiang, Yi Fudan Univ Sch Informat Sci & Technol Key Lab Informat Sci Electromagnet Waves MoE Shanghai 200433 Peoples R China Fudan Univ Engn Sch Informat Sci & Technol Dept Commun Sci Shanghai 200438 Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai 200050 Peoples R China

As a simple and popular transmission scheme, zero-forcing (ZF) precoding can effectively reap the great benefits of a multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) wireless system. But as the wireless technology evolves to massive MIMO-OFDM, even the ZF precoding may incur too cumbersome computational complexity. In this paper, we first derive the ZF precoder in the time domain. By exploiting the block-Toeplitzness of the time-domain channel matrix, we propose a novel approximate solution to the original time-domain ZF precoding problem for fast computation. We then provide an approximation analysis to show the convergence to the exact solution. To compute the approximate scheme efficiently, we propose two novel low-complexity algorithms: a fast Fourier transform (FFT) based conjugate gradient algorithm, which can obtain the MIMO-OFDM ZF precoder as a time-domain MIMO finite impulse response (FIR) filter, and a flexible block Toeplitz QR decomposition algorithm exploiting the special structure of the time-domain channel matrix. We also extend the proposed approximate scheme and two low-complexity algorithms to the regularized ZF precoding scenario. Simulation results and complexity analysis show that our methods can achieve favorable performance but with significantly lower computational complexity compared with the state-of-the-art methods.

关键词： Massive MIMO-OFDM zero-forcing precoding low computational complexity time domain precoding conjugate gradient QR decomposition

来源：评论

学校读者我要写书评

暂无评论

Performance analysis of zero-forcing precoding with signal space diversity under antenna correlation

引用

PHYSICAL COMMUNICATION 2018年 30卷 115-121页

作者： Ozyurt, Serdar Ankara Yildirim Beyazit Univ Fac Engn & Nat Sci Ankara Turkey

We consider a multiantenna transmission system where the transmitter and receiver respectively have M and two antennas. Specifically, zero-forcing precoding is employed at the transmitter based on a possibly imperfect channel state information (CSI). The channel estimation is carried out at the transmitter using pilot signals sent from the receiver. Adopting a dual-stream transmission structure, the error performance of the system is enhanced by resorting to signal space diversity (SSD). The performance of the proposed system with binary phase shift keying modulation is studied under a slow flat Rayleigh fading scenario with uncorrelated transmit antennas and correlated receive antennas. We separately examine two cases: the perfect CSI and imperfect CSI at the transmitter. In the former scenario, we provide an exact closed-form expression on the bit error probability (BEP) of the proposed approach. A tight approximation on the BEP of the proposed scheme is presented for the latter scenario. The case with distinct channel estimation qualities for the two subchannels is also considered in the second scenario. The proper rotation angles for the BPSK signal constellation are analytically obtained such that the derived expressions on the BEP are minimized under both cases. We show that the inclusion of SSD into the original scheme yields a noteworthy improvement on the BEP performance with only an insignificant increase in complexity and no additional use of bandwidth/time slots. It is also shown that the proposed technique is more immune against the channel estimation errors as compared to the original method. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Multiple-input multiple-output zero-forcing precoding Signal space diversity Rayleigh fading Channel state information Antenna correlation Channel estimation errors

来源：评论

学校读者我要写书评

暂无评论

Impact of Channel Aging on zero-forcing precoding in Cell-Free Massive MIMO Systems

引用

IEEE COMMUNICATIONS LETTERS 2021年第9期25卷 3114-3118页

作者： Jiang, Wei Schotten, Hans Dieter German Res Ctr Artificial Intelligence DFKI Intelligent Networking Res Grp D-67663 Kaiserslautern Germany Tech Univ TU Kaiserslautern Dept Elect & Comp Engn D-67663 Kaiserslautern Germany

In the context of cell-free massive multi-input multi-output (mMIMO), zero-forcing precoding (ZFP) requires the exchange of instantaneous channel state information and precoded data symbols via a fronthaul network. It causes considerable propagation and processing delays, which degrade performance. This letter analyzes the impact of channel aging on the performance of ZFP in cell-free mMIMO. The aging effects of not only user mobility but also phase noise are considered. Numerical results in terms of per-user spectral efficiency are illustrated.

关键词： Aging precoding Fading channels Phase noise Data communication Delays Downlink Cell-free massive MIMO backhaul delay channel aging outdated CSI phase noise zero-forcing precoding

来源：评论

学校读者我要写书评

暂无评论

Coordination/Cooperation Strategies and Optimal zero-forcing precoding Design for Multi-User Multi-Cell VLC Networks

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2019年第6期67卷 4240-4251页

作者： Pham, Thanh V. Pham, Anh T. Univ Aizu Comp Commun Lab Aizu Wakamatsu Fukushima 9658580 Japan

This paper studies multi-user multi-cell visible light communications networks in which each cell is composed of multiple light emitting diode (LED) arrays. The use of multiple LED transmitters enables each cell to support multiple users by means of precoding techniques. In such multi-user multi-cell networks, the signal for each user can be severely interfered not only by the signals that are intended to other users in the same cell, i.e., intra-cell interference, but also by the signals for users of the other cells, i.e., inter-cell interference. While intra-cell interference can be handled by the underlying precoding scheme, it is hard to deal with the inter-cell one. This paper focuses on cell coordination/cooperation strategies and their corresponding coordinated/cooperative precoder designs as the approaches to alleviate, or possibly, to cancel out the inter-cell interference. We first derive lower and upper bounds on the capacity of Gaussian interference channels with amplitude constraints on the input and the interference. Capitalizing on derived bounds and the zero-forcing scheme as the underlying precoding technique, optimal coordinated/cooperative precoding designs to maximize users' sum-rate are investigated under the non-negativity and amplitude-limited constraints on the channel inputs. The comprehensive numerical results are presented to compare the performance of the considered coordination/cooperation strategies.

关键词： VLC multi-user multi-cell VLC zero-forcing precoding cell coordination/cooperation coordinated/cooperative precoding

来源：评论

学校读者我要写书评

暂无评论

Limited feedback scheme based on zero-forcing precoding for Multiuser MIMO-OFDM Downlink Systems

Limited feedback scheme based on Zero-forcing Precoding for ...

引用

5th Annual ICST Wireless Internet Conference (WICON)

作者： Chen, Zhiyong Wang, Wenbo Peng, Mugen Caot, Fengming Beijing Univ Posts & Telecommun Minist Educ Key Lab Universal Wireless Commun Beijing Peoples R China Toshiba Res Europe Ltd Telecom Res Lab Bristol BS1 4ND Avon England

ISBN: (纸本)9789639799868

Conventional zero-forcing precoding was well investigated, but it hadn't considered the channel quality indicator (CQI) mismatch for practical system with limited feedback. This paper studies a novel zero-forcing precoding with channel quality indicator (CQI) estimation and adjusting, channel directional information(CDI) quantization, user scheduling and link adaptation and then proposes a CQI estimation algorithm for multiuser multiple input multiple output antenna (MU-MIMO) downlink systems with limited feedback. Simulation with 3GPP long term evolution system demonstrates that the scheme with proposed method can significantly improve system performance, compared with conventional zero-forcing precoding and single user MIMO systems.

关键词： zero-forcing precoding CQI CDI MMSE MU-MIMO

来源：评论

学校读者我要写书评

暂无评论

NONCAUSAL zero-forcing precoding SUBJECT TO INDIVIDUAL CHANNEL POWER CONSTRAINTS

NONCAUSAL ZERO-FORCING PRECODING SUBJECT TO INDIVIDUAL CHANN...

引用

20th European Signal Processing Conference (EUSIPCO)

作者： Li, Shenpeng Zhang, Jingxin Chai, Li Monash Univ Dept Elect & Comp Syst Engn Clayton Vic 3800 Australia Wuhan Univ Sci & Technol Sch Info Sci & Engn Wuhan 430081 Peoples R China

ISBN: (纸本)9781467310680

This paper investigates zero forcing (ZF) precoding in MIMO FB channels subject to individual channel power constraints. It shows that the optimal ZF precoder is noncausal in general and presents a general formulation for the design of optimal noncausal ZF precoder subject to individual channel power constraints. A convex optimization based method is derived from the formulation to design optimal noncausal precoder. Numerical example demonstrates the effectiveness of the design method and the advantage of the designed optimal noncausal ZF precoder.

关键词： zero-forcing precoding oversampled filter banks noncausal systems convex optimization

来源：评论

学校读者我要写书评

暂无评论

Codebook Design for the Finite Rate MIMO Broadcast Channel with zero-forcing precoding

Codebook Design for the Finite Rate MIMO Broadcast Channel w...

引用

54th Annual IEEE Global Telecommunications Conference (GLOBECOM)

作者： Egan, Malcolm Sung, Chang Kyung Collings, Iain B. Univ Sydney Sch Elect & Informat Engn Sydney NSW 2006 Australia CSIRO ICT Ctr Sydney NSW Australia

ISBN: (纸本)9781424492688

We present a novel codebook design criterion for the limited feedback MIMO broadcast channel with zero-forcing precoding. To reduce system implementation complexity, each user has the same codebook. We derive a new sum-rate bound, show the bound maximization problem is invex and explicitly solve it using the Karush-Kuhn-Tucker (KKT) conditions. We show that the solution has the same structure as Grassmannian frames. We also derive a new lower bound on the outage probability. We show via simulations that our codebooks designed using Grassmannian frames outperform random vector quantization with different codebooks at each user for codebook sizes greater than 9 bits.

关键词： Grassmannian frames Heating IEEE Communications Society Karush-Kuhn-Tucker conditions MIMO MIMO communication Shape Signal to noise ratio Transmitting antennas Vectors bound maximization problem broadcast channels codebook design finite rate MIMO broadcast channel optimisation outage probability precoding probability sum-rate bound zero-forcing precoding

来源：评论

学校读者我要写书评

暂无评论

Decentralization Issues in Cell-free Massive MIMO Networks with zero-forcing precoding 57

Decentralization Issues in Cell-free Massive MIMO Networks w...

引用

57th Annual Allerton Conference on Communication, Control, and Computing (Allerton)

作者： Riera-Palou, Felip Femenias, Guillem Univ Balearic Isl Mobile Commun Grp Mallorca Iiles Balears Spain

ISBN: (纸本)9781728131511

Cell-free massive MIMO (CF-M-MIMO) systems represent an evolution of the classical cellular architecture that has dominated the mobile landscape for decades. In CF-M-MIMO, a central processing unit (CPU) controls a multitude of access points (APs) that are irregularly scattered throughout the coverage area effectively becoming a fully distributed implementation of the M-IMO technology. As such, it inherits many of the key properties that have made M-MIMO one of the physical layer pillars of 5G systems while opening the door to new features not available in M-MIMO. Among the latest is the possibility of performing the precoding at the CPU (centralized) or at the APs (distributed) with the former known to offer much better performance at the cost of having to collect all the relevant channel state information (CSI) at the CPU. Realistic deployments of cell-free systems are likely to require more than one CPU when the area to be covered is large, thus a critical issue that needs to be solved is how these multiple CPUs should be interconnected. This paper analyzes and proposes designs for different degrees of interconnectivity among the CPUs for the specific case of centralized zero-forcing precoding. Results show that a modest form of CPU interconnection can boost very significantly the max-min rate performance so prevalent in CF-M-MIMO architectures.

关键词： Cell-free Massive MIMO zero-forcing precoding Clustering max-min performance

来源：评论

学校读者我要写书评

暂无评论

Optimal zero-forcing precoding Design - Oversampled FB Frame Approach

Optimal Zero-Forcing Precoding Design - Oversampled FB Frame...

引用

2010 IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Li, Shenpeng Zhang, Jingxin Chai, Li Monash Univ Dept Elect & Comp Syst Engn Clayton Vic 3800 Australia Wuhan Univ Sci & Technol Sch Informat Sci & Engn Wuhan 430081 Peoples R China

ISBN: (纸本)9781424442966

This paper presents a frame analysis of zero forcing (ZF) precoding problem. It shows that from a frame point of view, the filter bank (FB) channel is a synthesis frame and its canonical dual analysis frame is the optimal ZF precoder under total power constraint. Based on this analysis, a new precoder design is presented. The new design removes the minimum phase assumption of polyphase FB channel in the existing methods and gives rise to optimal noncausal (stable) precoder. It provides a general framework for optimal zero-forcing precoding under total power constraint. The numerical results show that the new design outperforms existing causal stable design.

关键词： zero-forcing precoding oversampled filter banks dual frame state space approach

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：