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research Framework of B3G mobile communications Systems

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ZTE communications 2006年第2期4卷 29-34页

作者： Chen Ming, You Xiaohu (national mobile communications research laboratory, southeast university, nanjing 210096, china)

Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transmission rate, enlarged range of transmission rates, more spatial and temporal distribution differences, and more service transmission requests occurring in fast moving vehicles. In order to meet the requirements of B3G services, the B3G systems must have great improvement in network architecture, air interface scheme, radio resource allocation strategy, frequency bands, and Radio Frequency (RF) technology etc. Therefore, the research of the B3G systems should focus on the theory of generalized cellular communications networks, theory of the Multiple Input Multiple Output (MIMO) wireless transmission system, matching of radio resources to new-type air interfaces, new iterative detection and adaptive link methods, and new-type antenna and RF technologies.

关键词： MIMO IEEE USA research Framework of B3G mobile communications Systems

Mechanical behavior of a shelter system based on cable-strut structures

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2012年第12期13卷 895-903页

作者： Jian-guo CAI1,2,Ya ZHOU1,Jian FENG1,2,Yi-xiang XU3 (1Key laboratory of C&PC Structures of Ministry of Education,southeast university,nanjing 210096,china) (2national Prestress Engineering research Center,southeast university,nanjing 210096,china) (3Department of Civil Engineering,Strathclyde university,Glasgow,UK) 1. Key laboratory of C&PC Structures of Ministry of Education Southeast University Nanjing 210096 China 2. national Prestress Engineering research Center Southeast University Nanjing 210096 China 3. Department of Civil Engineering Strathclyde University Glasgow UK

A shelter system based on cable-strut structures,consisting of compressive struts and high-tensile elements,is described in this *** deployment of the shelter is achieved by tightening inclined *** cables are used to terminate the *** state of self-stress of the cable-strut structures in the fully deployed configuration is given,and the minimum strut length and the maximum load design of the shelter are *** mechanical behavior of the system was studied under symmetrical and asymmetrical load *** results show that the shelter in the deployed configuration satisfies the ultimate limit and the serviceability limit state ***,the stability of the cable-strut system is investigated,considering the effect of imperfections on the buckling of the *** conclude that the influence of imperfections based on the consistent imperfection mode method is not significant.

关键词： Foldable structures Cable-strut structures Mechanical behavior Self-stress Stability

Asymptotic bound on binary self-orthogonal codes

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Science china Mathematics 2009年第4期52卷 631-638页

作者： DING Yang Department of Mathematics, southeast university, nanjing 210096, china 1. Department of Mathematics Southeast University Nanjing 210096 China

We present two constructions for binary self-orthogonal codes. It turns out that our constructions yield a constructive bound on binary self-orthogonal codes. In particular, when the in-formation rate R = 1/2, by our constructive lower bound, the relative minimum distance δ≈ 0.0595 (for GV bound, δ≈ 0.110). Moreover, we have proved that the binary self-orthogonal codes asymptotically achieve the Gilbert-Varshamov bound.

关键词： algebraic geometry codes concatenated codes Gilbert-Varshamov bound Reed-Muller codes self-dual basis self-orthogonal codes 11T71

Study on QoS and communications Capacity in Heterogeneous Network Convergence

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ZTE communications 2008年第3期6卷 6-9页

作者： Xia Weiwei,Shen Lianfeng(national mobile communications research laboratory,southeast university,nanjing 210096,china)

To provide any subscriber from anywhere at anytime with services that have both secured Quality of Service(QoS) and simultaneous expansion of network coverage and communications capacity is a key problem that has to be considered and solved in heterogeneous network *** technologies for a secured QoS and communications capacity analysis under heterogeneous environment are important subjects for *** technologies for a secured QoS are mainly on radio resource management algorithms covering Call Admission Control(CAC) algorithm,vertical handover algorithm,heterogeneous resource allocation algorithm and network selection *** applications of a novel multi-hop in heterogeneous convergence system serve the purposes of network coverage expansion,transmission power reduction,system communication capacity and throughput increase.

关键词： QoS Study on QoS and communications Capacity in Heterogeneous Network Convergence WLAN IEEE

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 university of Posts and Telecommunications, nanjing 210003, china 2. national mobile communications research Lab, southeast university, nanjing 210096, china [a]Jiangsu Key laboratory of Wireless communications and Institute of Signal Processing and Transmission nanjing university of Posts and Telecommunications nanjing 210003 china [b]national mobile communications research Lab southeast university nanjing 210096 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

A research into the large-scaled spatial forms of cities based on urban design

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Science china(Technological Sciences) 2009年第9期52卷 2486-2496页

作者： WANG JianGuo School of Architecture, Key laboratory of Urban and Architectural Heritage Conservation of Ministry of Education, southeast university, nanjing 210096, china 1. School of Architecture Key laboratory of Urban and Architectural Heritage Conservation of Ministry of Education Southeast University Nanjing 210096 China

In the process of unprecedented urbanization in contemporary china, a great many of Chinese cities have witnessed a rapid expansion of urban scale to different degrees. With the continuous compilation, amendment and enforcement of urban planning, the functional structure, spatial environment, street patterns and textures and even the social aspect of cities have changed conspicuously, all of which have directly happened to the spatial forms of the dimension, or even the multi-dimension of a certain city. By describing and analyzing the structure, evolution and explicit tokens of the spatial forms of cities, this thesis attempts to set up a model of factors that affect urban forms, as well as discuss the attributes, protection, adjustment and development-potential of urban land closely associated with forms. In addition, on the basis of the professional features for urban design to participate in the modeling and construction-management of desirable spatial forms of cities, the author has put forward technical measures for quantitatively appraising and analyzing the large-scaled spatial forms of cities, thus offering technical support to municipal governments and management departments of planned construction.

关键词： large-scaled spatial forms of cities urban design digital technology

Integrated intelligent control analysis on semi-active structures by using magnetorheological dampers

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Science china(Technological Sciences) 2008年第12期51卷 2270-2284页

作者： XU ZhaoDong1 & GUO YingQing2 1Civil Engineering College, southeast university, nanjing 210096, china 2 Automation College, southeast university, nanjing 210096, china Civil Engineering College Southeast University Nanjing 210096 China Automation College Southeast University Nanjing 210096 China

The control strategy is very important for semiactive control or active control systems. An integrated intelligent control strategy for building structures incorpo rated with magnetorheological (MR) dampers subjected to earthquake excitation is proposed. In this strategy, the time-delay problem is solved by a neural network and the control currents of the MR dampers are determined quickly by a fuzzy controller. Through a numerical example of a three-storey structure with one MR damper installed in the first floor, the seismic responses of the uncontrolled, the intelligently controlled, the passiveon controlled, and the passive-off controlled structures under different earthquake excitations are analyzed. Based on the numerical results, it can be found that the time domain and the frequency domain responses are reduced effectively when the MR damper is added in the structure, and the integrated intelligent control strategy has a better earthquake mitigation effect.

关键词： magnetorheological damper semi-active control intelligent

LOW-COMPLEXITY BLIND MULTIUSER DETECTION OF DS-CDMA SIGNAL IN DISPERSIVE CHANNELS

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Journal of Electronics(china) 2001年第4期18卷 330-336页

作者： Lin Zhiqiang You Xiaohu Wang Yong(national mobile communications research laboratory, southeast university, nanjing 210096) national mobile communications research laboratory Southeast University Nanjing 210096

The problem of blind multiuser detection in dispersive channels of Code-Division Multiple-Access (CDMA) in the presence of both Multiple-Access Interference (MAI) and InterSymbol Interference (ISI) is considered. In practice, it is showed that by incorporating the desired user's signature waveform and the auxiliary vector, the information of the user can be identified using the suboptimal subspace method. The major contribution of this paper is to propose a minimum-mean-square-error detector with the suboptimal subspace-based blind technique for joint suppression of MAI and ISI in the dispersive CDMA channels.

关键词： Code-division multiple-access Multiuser detection Multiple-access interference Intersymbol interference

PRERAKE JOINT WITH STTCM FOR TDD DS-CDMA SYSTEM

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Journal of Electronics(china) 2001年第4期18卷 337-345页

作者： Cheng Jian Wu Gang Cheng Shixin (national mobile communications research laboratory, southeast university, nanjing 210096) national mobile communications research laboratory Southeast University Nanjing 210096

A novel synthetical transmit diversity, namely Prerake joint with Space-Time Trellis Coded Modulation (STTCM), for TDD DS-CDMA system is proposed in this paper. Space-Time Code (STC) is applied under the multipath fading circumstance. Prerake is used in stead of Rake to overcome multipath fading for the simplicity of the receiver configuration. Through computer simulation, the performance of our proposed scheme in multipath fading can be better than that of just STC is used, the taps of the Prerake should be chosen to be equal to the multipath number in the matter of minimum mean square error. A new constellation (8APK) is presented to construct a kind of STC that achieves better performance than that of 8PSK.

关键词： Prerake Space-Time Code (STC) Transmit diversity Multipath fading CDMA