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Performance analysis of variable-power adaptive modulation in space-time block coded MIMO diversity systems

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Science china(Information Sciences) 2010年第10期53卷 2106-2115页

作者： YU XiangBin 1,2.& SHI HuiBin 1 1 College of Information Science and Technology, nanjing university of Aeronautics and Astronautics, nanjing 2.0016, china 2.national mobile communications research Laboratory, southeast university, nanjing 2.0096, china 1. College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In this paper, the performance analysis of multi-antenna MIMO systems with variable-power (VP) adaptive modulation and space-time coding is presented. The fading gain value is partitioned into a number of regions by which we decide the transmission power according to the region the fading gain falls in. The optimum fading gain region boundaries (switching thresholds) for maximizing spectrum efficiency (SE) under a target BER and average power constraint are derived. It is shown that the Lagrange multiplier in the constrained SE optimization will be unique if the existence condition for multi-antenna systems is satisfied, and is unique for single antenna systems. A practical iterative calculation method based on Steepest Descent Algorithm for finding the Lagrange multiplier is proposed. With the switching thresholds, the closed-form expressions of the SE and average BER, respectively for VP system and constant-power (CP) system are achieved. Simulation results for SE and average BER are in good agreement with the theory analysis. The results show that VP adaptive modulation with space-time coding provides better SE than the counterpart with CP under a target BER and average power constraint.

关键词： adaptive modulation variable power space-time block code constant power multiple input multiple output (MIMO)

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

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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,{2. 2.0007,china 2.national mobile communications research Laboratory,southeast university,nanjing 2.0096,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

Blind estimation of multipath delays in OFDM systems

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Science china(Information Sciences) 2012年第6期55卷 1397-1401页

作者： SHENG Bin & YOU XiaoHu national mobile {2. research Laboratory,southeast university,nanjing 2.0096,china 1. national mobile {2. research Laboratory Southeast University Nanjing 210096 China

In order to coherently detect the transmitted data symbols,an orthogonal frequency division multi-plexing (OFDM) receiver requires reliable identification and equalization of the experienced wireless multipath fading *** information of path delays plays an important role in the procedure of identification and *** need for high data rates motivated the search for blind identification and equalization methods because they save bandwidth by avoiding the use of training *** OFDM systems,multipath fading channels introduce interference between adjacent symbols which can be prevented by inserting a cyclic prefix (CP) before each *** this paper,we find that the power of the interference in the CP interval can be estimated by using the circular convolution and based on the variations of the interference power,the time delay of each path can be estimated blindly.

关键词： multipath delay cyclic prefix OFDM

Multi-user MIMO downlink eigen-mode transmission over jointly correlated MIMO channels

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Science china(Information Sciences) 2011年第10期54卷 2124-2137页

作者： LI Xiao ,JIN Shi & GAO XiQi national mobile {2. research Laboratory,southeast university,nanjing 2.0096,china 1. national mobile {2. research Laboratory Southeast University Nanjing 210096 China

The study of multi-user multiple-input multiple-output (MU-MIMO) systems has emerged recently as an important research topic because such systems have the potential to combine the high capacity that can be achieved through MIMO processing with the benefits of spatial-division ***,receiver and transmitter channel state information (CSI) is generally required,especially for the downlink *** this paper,MU-MIMO downlink transmission systems with statistical CSI at the transmitter are studied for jointly correlated MIMO ***-mode space division multiple access transmission is derived based on the maximization of the ergodic sum rate,and two eigen-mode power allocation algorithms are proposed using matrix permanent and convex optimization *** new algorithms can overcome the limitations of the existing multi-user downlink transmission algorithm in practical applications.

关键词： MIMO eigen-mode multi-user downlink

中国政治经济学年度发展报告（2.2.）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,research Institute for 2.st-Century Marxism,Nankai university·university of Chinese Academy of Social Science Center for Teaching and research on Capital,Renmin university of china national Institute of Socialist Political Economy with Chinese Characteristics,Renmin university of china 南开大学·中国社会科学院大学2.世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2.2.年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2.2.）》。自2.10年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2.2.年报告聚焦12.专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12.报告（下）篇刊登。2.2.年报告（下）选题如下：

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Linear beamformer schemes with simple relay selection in MIMO relay networks

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The Journal of china Universities of Posts and Telecommunications 2008年第4期15卷 24-29+39页

作者： MENG Qing-min 1,2. PAN Su1, ZHENG Bao-yu1, ZHU Hong-bo1, YOU Xiao-hu2.1. Jiangsu Key Laboratory of Wireless communications and Institute of Signal Processing and Transmission, nanjing {2. of Posts and Telecommunications, nanjing 2.0003, china 2. national mobile communications research Lab, southeast university, nanjing 2.0096, china [a]Jiangsu Key Laboratory of Wireless communications and Institute of Signal Processing and Transmission nanjing university of Posts and Tele{2. nanjing 2.0003 china [b]national {2. communications research Lab southeast university nanjing 2.0096 china

This article considers a wireless multi-hop/mesh network where single multi-antenna source-destination pair communicates through a selected relay subset using simple relay selection under the constraint of fixed relay’s number. Compared with random selection, the simple relay selection can yield certain capacity advantages while linear zero-forcing (ZF) receiver and linear beamformer are considered at the relay. For match-filter (MF) beamformer and amplified-and-forward (AF) beamformer with a fixed number of relays, the capacities are given. Furthermore, we extend the simple selection methods to the relaying scheme with orthogonal-triangular (QR) beamformer and investigate these linear beamformer schemes over spatially correlated multi-input multi-output (MIMO) links for both the backward and forward channel over the two-hop MIMO relay networks.

关键词： wireless mesh networks multi-hop relaying capacity beamformer

Performance analysis of uplink MIMO MC-CDMA systems based on linear zero-forcing V-BLAST algorithm

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Science in china(Series F) 2008年第9期51卷 1305-1318页

作者： YANG Wei1,2.& YANG Wei1 1 State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong university,Beijing 100044,china {2. mobile communications research Laboratory,southeast university,nanjing 2.0096,china 1. State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China 2. national mobile {2. research Laboratory Southeast University Nanjing 210096 China

A structure was proposed for multiple-input-multiple-output multicarrier code divi- sion multiple access （MIMO MC-CDMA） uplink transmission system. Linear zero- forcing V-BLAST （ZF V-BLAST） algorithm and maximum ratio combining （MRC） scheme was applied to the receivers. The average bit error rate （BER） expression was derived on condition that the number of receive antennas was larger than that of transmit antennas and it was verified by simulations. Numerical results show that the number of transmit and receive antennas, as well as the number of sub- carriers, all exert significant effects on the BER performance. The space diversity and frequency diversity show different abilities to improve the BER performance. The MIMO MC-CDMA system based on linear ZF V-BLAST algorithm is capable of achieving better BER performance than that of the conventional MC-CDMA system by reducing the number of transmit antennas or increasing the number of receive antennas.

关键词： bit error rate(BER) multiple-input-multiple-output(MIMO) multicarrier code division multiple access(MC-CDMA) zero-forcing(ZF)

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Nonlinear codes with asymptotic parameters better than the Gilbert-Varshamov and the Xing Bounds

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Science china Mathematics 2006年第6期49卷 852-864页

作者： HU Wanbao Department of Mathematics, Anqing Teachers College, Anqing 2.6011, china national {2. communications research, Southest university, nanjing 2.0096, china 1. Department of Mathematics Anqing Teachers College Anqing 246011 China 2. national mobile {2. research Southest University Nanjing 210096 China

In this paper, we show that the Gilbert-Varshamov and the Xing bounds can be improved significantly around two points where these two bounds intersect by nonlinear codes from algebraic curves over finite fields.

关键词： nonlinear code, algebraic curve, Gilbert-Varshamov bound, Xing bound.

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On the number of rotation symmetric Boolean functions

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Science china(Information Sciences) 2010年第3期53卷 537-545页

作者： FU ShaoJing1, LI Chao1,2.& QU LongJiang1,3 1Science College of national university of Defense Technology, Changsha 410073, {2. 2.tate Key Laboratory of Information Security, Beijing 100039, {2. 3national mobile communications research Laboratory, southeast university, nanjing 2.0096, {2. 1. Science College of national university of Defense Technology Changsha 410073 China2. State Key Laboratory of Information Security Beijing 100039 China3. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

Rotation symmetric Boolean functions (RSBFs) have been used as components of different cryptosystems. This class of functions are invariant under circular translation of indices. In this paper, we investigated balanced RSBFs and 1st order correlation immune RSBFs. Based on constructive techniques, we give an accurate enumeration formula for n-variable balanced RSBFs when n is a power of a prime. Furthermore, an original and efficient method to enumerate all n-variable (n prime) 1st order correlationimmune functions is presented. The exact number of 1st order correlation immune RSBFs with 11 variables is 692.04715655047882.2.52.037412.76451107768477380552.800 and the number of 13 variables has 189 digits. Then for more variables, we also provide a significant lower bound on the number of 1st order correlation immune RSBFs.

关键词： cryptography rotation symmetry correlation immunity balancedness