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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 210096,china School of Mathematics Hefei University of Technology Hefei China national mobile communications research laboratory Southeast University Nanjing 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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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 210096,china Institute of communications Engineering PLA University of Science and Technology Nanjing China national mobile communications research laboratory Southeast University Nanjing 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

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 national mobile communications research laboratory,southeast university,nanjing 210096,china State Key laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China national mobile communications research laboratory Southeast University Nanjing 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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research and Simulation on Non-Blind Adaptive Beamforming Algorithm for TD-SCDMA System

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Research and Simulation on Non-Blind Adaptive Beamforming Al...

A Cumulant-Based Beamforming Algorithm for CDMA Frequency-nonselective Fading Channel

中国通信学会第六届学术年会

作者： Mengjuan Yu~1,Lianfeng Shen~1,Bo Xu~2 (1 national mobile communications research laboratory,southeast university,nanjing 210096,china 2 Institute of communications Engineering,PLA university of Science and Technology,nanjing 210018,china)

Adaptive beamforming algorithms continue to be a research hotspot of smart *** adaptive beamforming algorithms, non-blind adaptive algorithms attract most researchers'''' interests because they have better feasibility,stability performance and they are not affected by the accuracy of DOA *** performance of non-blind adaptive algorithms used in TD-SCDMA communication system has not been studied and simulated in-depth *** paper tries to simulate and compare three typical nonblind adaptive algorithms including Least Mean Square algorithm(LMS),Recursive Least Squares algorithm(RLS),the Sample Covariance Matrix Inversion algorithm(SMI) for TD-SCDMA *** simulation results show that all three algorithms can mitigate interferences,save power and improve the quality of *** simulation also indicates that better performances and applicability are obtained when the weights are estimated using the RLS algorithm than the LMS and SMI algorithms.

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Wuhan university Journal of Natural Sciences 2002年第3期7卷 327-332页

作者： Yang Wei 1 , Cheng Shi\|xin 2 1. School of Electronics and Information Engineering, Northern Jiaotong university, Beijing 100044, china 2. national mobile communications research laboratory, southeast university, nanjing 210096, Jiangsu, china School of Electronics and Information Engineering Northern Jiaotong University Beijing 100044 China national mobile communications research laboratory Southeast University Nanjing 210096 Jiangsu China

A cumulant-based beamforing technique for synchronous CDMA system with decorrelator is presented. With decorrelating detector the proposed algorithm has the advantages that the steering vector of desired user’s can be estimated independently by eliminating all the other resolved signal interferences. Furthermore employing cumulant-based signal processing technique the steering vector of the decoupled signals can be estimated blindly. Simulation results show that the cumulant-based beamformer demonstrates excellent performance.

关键词： antenna array CDMA beamforming cumulant

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Signal Design for Ultra-Wide-Band Wireless communications in Indoor Environment with Presence of Narrow-band Interference

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Signal Design for Ultra-Wide-Band Wireless Communications in...

A Dynamic Algorithm of Video Super-resolution Enhancement Based on Adaptive Filter

教育部中南地区高等学校电子电气基础课教学研究会第二十届学术年会

作者： Xie Ning~(1,2) Wang Hui~1 (1.College of Information Engineering,Shenzhen university,Shenzhen,Guangdong 518060,china.2. national mobile communications research laboratory,southeast university,nanjing,Jiangsu 210096, china.

A signal design method for UWB wireless systems is *** method optimizes the time delay parameter of signals in UWB wireless systems which meet the Federal communications Commission spectrum requirement in realistic communications *** on the system performance with the proposed signal design is *** issues of the radio channel responses,the antenna characteristics,the narrow-band interference and *** *** numerical results illustrate the effectiveness of the proposed design method.

关键词： Ultra-wide-band communications signal design narrow-band interference indoor environments.

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A Dynamic Algorithm of Video Super-resolution Enhancement Ba...

Blind estimation of multipath delays in OFDM systems

第二届和谐人机环境联合学术会议(HHME2006)——第15届中国多媒体学术会议(NCMT'06)

作者： HAN Yu-Bing1+, SHU Feng1, 2, RUI Yi-Bin1, LI Peng1 1(School of Electronic Engineering & Optoelectronic Techniques, nanjing university of Science & Technology, nanjing 210094, china) 2(national mobile communications research laboratory, southeast university, nanjing 210096, china)

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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 communications research laboratory,southeast university,nanjing 210096,china national mobile communications research laboratory Southeast University Nanjing 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 communications research laboratory,southeast university,nanjing 210096,china national mobile communications research laboratory Southeast University Nanjing 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