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Adaptive subcarrier allocation for MIMO-OFDMA Wireless Systems Based on Beamforming

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Journal of Donghua University(English Edition) 2010年第3期27卷 425-429页

作者：管张均张唯炯周希朗郭强 Department of Electronic Engineering Shanghai Jiaotong University

Beamforming is a kind of signal processing technique which can improve system performance in the multiple-input multiple-output(MIMO)*** this paper,the problem of allocating subcarriers in MIMO-OFDMA wireless systems was analyzed,and a scheme to allocate subcarriers among all users based on beamforming was proposed to maximize the signal-to-noise ratio(SNR)at the *** properties of the channel matrix were studied,and some beneficial results were *** channel state information(CSI)was also taken into account to simulate more practical *** results show that the proposed allocating scheme is effective,and it is robust to the influence of delayed CSI.

关键词： MIMO-OFDMA subcarrier allocation beamforming

Optimal subcarrier allocation for cognitive radio with multi-user OFDM and distributed antenna

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Journal of Southeast University(English Edition) 2010年第4期26卷 513-517页

作者：葛文栋纪红司鹏搏李曦北京邮电大学泛网无线通信教育部重点实验室北京100876 北京工业大学电子信息与控制工程学院北京100022

The subcarrier allocation problem in cognitive radio（CR）networks with multi-user orthogonal frequency-division multiplexing（OFDM）and distributed antenna is analyzed and modeled for the flat fading channel and the frequency selective channel,where the constraint on the secondary user（SU）to protect the primary user（PU）is that the total throughput of each PU must be above the given threshold instead of the ＂interference temperature＂.According to the features of different types of channels,the optimal subcarrier allocation schemes are proposed to pursue efficiency（or maximal throughput）,using the branch and bound algorithm and the 0-1 implicit enumeration ***,considering the tradeoff between efficiency and fairness,the optimal subcarrier allocation schemes with fairness are proposed in different fading channels,using the pegging *** simulation results illustrate the significant performance improvement of the proposed subcarrier allocation schemes compared with the existing ones in different scenarios.

关键词： cognitive radio subcarrier allocation multi-user OFDM distributed antenna branch and bound algorithm implicit enumeration algorithm pegging algorithm

BLOCK ADAPTIVE subcarrier allocation FOR WIRELESS MULTIUSER OFDM SYSTEM

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Journal of Electronics(China) 2004年第6期21卷 454-460页

作者： LiangXiaowen ZhuJinkang PCN＆SSLab DeptofElectronicsEngineeringandInformationScienceUniversityofScienceandTechnologyofChinaHefei230027

In this paper, a blockwise adaptive subcarrier allocation algorithm for multiuser Orthogonal Frequency Division Multiplexing (OFDM) system is introduced. Assuming the knowledge of channel information for all users, the algorithm minimizes the total transmit power while satisfying the total power and users' rate constraints. The result of simulation shows that the proposed algorithm reduces the average bit Signal-to-Noise Ratio (SNR) by approximately 4 dB compared with OFDM-Frequency Division Multiple Access (OFDM-FDMA), and supports more users in a multiuser Rayleigh fading channel. As assigning subcarriers in block, the computational complexity of the algorithm is much lower than that of the derivation of "water-filling" algorithm.

关键词： Orthogonal Frequency Division Multiplexing(OFDM) Multiuser subcarrier allocation Rayleigh fading channel

A QoS-Aware subcarrier allocation Algorithm with Perfect Channel Information in OFDMA Based Systems

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A QoS-Aware Subcarrier Allocation Algorithm with Perfect Cha...

A Novel subcarrier allocation Scheme for Adaptive Multi-user MIMO-OFDM Systems to Maximize the System Capacity

第一届中国高校通信类院系学术研讨会

作者： jiang Haiping~(1,2) Deng Ping~2 Yang Yubo~1 Shi Jinglin~1 Dong Wenxia~(1,2) (1.Institute of Computing Technology,China Academy of Science,Beijing 100080,China 2.School of Information Science & Technology,Southwest Jiaotong University,Chengdu 610031,China)

＜正＞Orthogonal Frequency Division Multiple Access （OFDMA） is a emerging multiple access scheme to be used for future broadband wireless communication *** OFDMA based systems,the systems commonly allocate subcarriers dynamically to users in a pseudo-random way.A key issue at hand is how to find the effective subcarrier allocation algorithm to provide quality-of-service （QoS） for *** this paper,a novel subcarrier allocation algorithm is proposed and *** proposed algorithm tries to improve the system’s throughput and guarantee fairness between the users while not increasing its computational *** results show that compared with other algorithm,the proposed algorithm can guarantee users’ OoS requirements.

关键词： QoS OFDMA subcarrier allocation

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A Novel Subcarrier Allocation Scheme for Adaptive Multi-user...

Joint subcarrier and power allocation in uplink OFDMA systems based on stochastic game

第十二届全国青年通信学术会议

作者： Guoliang Shen Shouyin Liu Dept.of Electronic and Information Engineering,Huazhong Normal University Wuhan 430079,China

＜正＞In this paper,we investigate the subcarrier allocation schemes for downlink adaptive multi-user multiple input multiple output-orthogonal frequency division multiplexing（MIMO-OFDM）*** categories of subcarrier assignment criteria to maximize the system capacity are obtained in this paper,that is,Frobenius norm criterion（FNC）and Infinite norm criterion（INC）.Our proposed algorithm is able to:①optimize the system capacity;②avoid the conflict between users;③ensure fairness of all the users;④satisfy the QoS requirements of the user whose channel condition is always *** is assumed that the transmitter and receiver both have the perfect channel state information（CSI）.Simulation results show that the system capacity which is achieved by our proposed subcarrier allocation criteria is much higher than fixed subcarrier allocation scheme.

关键词： subcarrier allocation Adaptive Multi-User

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Science China(Information Sciences) 2010年第12期53卷 2557-2566页

作者： WU Dan 1,CAI YueMing 1,2 & SHENG YanMing 1 1 Institute of Communications Engineering,PLA University of Science and Technology,Nanjing 210007,China 2 National Mobile Communications Research Laboratory,Southeast University,Nanjing 210096,China 1. Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 China2. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In uplink orthogonal frequency division multiplexing access(OFDMA) systems,efficient resource allocation can greatly improve system ***,in this paper,we present a game-theoretical approach to achieve a joint subcarrier and power allocation in a distributed ***,the subcarrier allocation problem is modeled as a multi-player discrete,stochastic and finite strategy game,where each of the subcarriers is viewed as a player to choose the most satisfying *** subcarriers of each user are allocated with equal *** the proposed game model,on the one hand,we exploit the support and programming methods to obtain the Nash equilibriums,and analyze their theoretical *** the other hand,we propose a lowcomplexity algorithm based on the linear reward-inaction(L R-I) algorithm to search for the Nash *** the relationship between the convergence results of this algorithm and the Nash equilibriums is *** simulation results demonstrate the effectiveness of the resource allocation game model and algorithm.

关键词： stochastic game OFDMA subcarrier allocation power allocation learning automata linear reward-inaction