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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 communications research laboratory,southeast university,nanjing 2.0096,china 1. national mobile communications 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（2023）（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 21st-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21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2023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2023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（2023）》。自2010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。2023年报告聚焦12个专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12由报告（下）篇刊登。2023年报告（下）选题如下：

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Spectral Estimation based on Filter Bank and Cepstrum Thresholding for Cognitive Radios

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china communications 2009年第1期6卷 92-98页

作者： Cao Zhiping, Bi Guangguo, Zhang Zaichen national mobile Communication research laboratory, School of Information Science and Engineering, southeast university, nanjing 2.0096, china national mobile Communication research laboratory School of Information Science and Engineering Southeast University Nanjing 210096 China

Spectrum sensing plays an important role in cognitive radio (CR). Nonparametric spectrum estimation is considered as a feasible candidate for CR. Some filter bank based periodogram algorithms, such as Thomson’s multitaper spectral estimator, can achieve fine spectral dynamic range1 but have large estimation variance. On the other hand, recently, Cepstrum Thresholding is proposed to reduce the variance of periodogram estimation. In this paper, we combine these two methods to achieve spectral dynamic range and variance request at the same time.

关键词： spectrum analysisfifilter bank cepstrum thresholding.

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 210016, 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,nanjing 210007,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

Negacyclic codes over Galois rings of characteristic 2a

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Science china Mathematics 2012年第4期55卷 869-879页

作者： ZHU ShiXin 1,2,& KAI XiaoShan 1,2 1 School of Mathematics,Hefei university of Technology,Hefei 230009,china 2 national mobile communications research laboratory,southeast university,nanjing 2.0096,china 1. School of Mathematics Hefei University of Technology Hefei 230009 China2. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

Abstract We investigate negacyclic codes over the Galois ring GR（2a,m） of length N = 2kn, where n is odd and k≥0. We first determine the structure of u-constacyclic codes of length n over the finite chain ring GR（2a, m）[u]/〈u2k ＋ 1〉. Then using a ring isomorphism we obtain the structure of negacyclic codes over GR（2a, m） of length N = 2kn （n odd） and explore the existence of self-dual negacyclic codes over GR（2a, m）. A bound for the homogeneous distance of such negacvclic codes is also given.

关键词： negacyclic codes constacyclic codes Galois rings self-dual codes homogeneous distance

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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 246011, china national mobile communications research, Southest university, nanjing 2.0096, china 1. Department of Mathematics Anqing Teachers College Anqing 246011 China 2. national mobile communications 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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A　Homotopy-Controlled　Mean　Field　Annealing　Partially-Connected　Neural　Equalizer　for　Pan-European　GSM　System

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通信学报 1997年第3期 36-44页

作者： Xue Jianjun You Xiaohu (national communications research laboratory southeast university, nanjing 210018)

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ＡＨｏｍｏｔｏｐｙ┐ＣｏｎｔｒｏｌｅｄＭｅａｎＦｉｅｌｄＡｎｎｅａｌｉｎｇＰａｒｔｉａｌｙ┐ＣｏｎｎｅｃｔｅｄＮｅｕｒａｌＥｑｕａｌｉｚｅｒｆｏｒＰａｎ┐ＥｕｒｏｐｅａｎＧＳＭＳｙｓｔｅｍ＊Ｔｈｉｓｗｏｒｋｗａｓｓｕｐｐｏｒｔｅｄｉｎｐａｒｔｂｙｔｈ...

关键词： neural equalizer GSM system

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, china 2State Key laboratory of Information Security, Beijing 100039, china 3national mobile communications research laboratory, southeast university, nanjing 2.0096, china 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 6925047156550478825225250374129764511077684773805520800 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