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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 21.096,china 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

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)

A sub-block orthogonal single carrier frequency domain equalization system in fast Rayleigh fading channel

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Science china(Information Sciences) 2010年第9期53卷 1833-1847页

作者： LIU Rui*,GAO XiQi* & WANG WenJin national Communication research laboratory,southeast university,nanjing 21.096,china 1. national Communication research laboratory Southeast University Nanjing 210096 China

In this paper,we analyze the frequency domain linear equalization(FDLE) of single carrier block transmission(SCBT) systems under fast fading ***,we propose a new approximating model in which the channel is assumed to be static in sub-blocks vary each *** on this model,we derive a new 2-orthogonal-sub-blocked frequency domain equalization ***,we derive the conditions of the channel under which the equalization method can be applied to the 2-orthogonal-sub-blocked *** demonstrates that the proposed method can improve the anti-Doppler ability of SC-FDLE and at the same time keep its high efficiency and low complexity.

关键词： SCBT SC-FDE LMMSE

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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Science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2, BI GuangGuo3 & XU WeiYe4 1 College of Information Science and Technology, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 2 Department of Electronic Engineering, City university of Hong Kong, Hong Kong, china 3 national mobile communications research laboratory, southeast university, nanjing 21.096, china 4 Department of Communication Engineering, nanjing Institute of Technology, nanjing 211167, china College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Electronic Engineering City University of Hong Kong Hong Kong China national mobile communications research laboratory Southeast University Nanjing 210096 China Department of Communication Engineering Nanjing Institute of Technology Nanjing 211167 China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

The renascence of industrial historic buildings——Taking the protective remolding and reusing of Chenguang Mechanical Factory in nanjing as an example

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Science china(Technological Sciences) 2009年第9期52卷 2502-2509页

作者： WANG YanHui research Institute of Architecture,southeast university,nanjing 21.096,china 1. research Institute of Architecture Southeast University Nanjing 210096 China

The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.

关键词： industrial historic buildings and sites protective remolding and reusing renascence strategy

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 21.096, 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

Analyzing architecture articles

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中国科学：技术科学英文版 2010年第7期53卷 1739-1742页

作者： QI Kang research Institute of Architecture, southeast university, nanjing 21.096, china 1. research Institute of Architecture Southeast University Nanjing 210096 China

In the present study, we express the quality, function, and characteristics of architecture to help people comprehensively understand what architecture is. We also reveal the problems and conflict found in population, land, water resources, pollution, energy, and the organization systems in construction. china’s economy is transforming. We should focus on the cities, architectural environment, energy conservation, emission-reduction, and low-carbon output that will result in successful green development. We should macroscopically and microscopically analyze the development, from the natural environment to the artificial environment; from the relationship between human beings and nature to the combination of social ecology in cities, and farmlands. We must learn to develop and control them harmoniously and scientifically to provide a foundation for the methods used in architecture research.

关键词： architecture science sustainable development

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 21.096, 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 21.096 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

Dispersion of ventricular mRNA of RyR2 and SERCA2 associated with arrhythmogenesis in rats

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Acta Pharmacologica Sinica 2004年第6期25卷 36-41页

作者： Hong-lan WANG, De-zai DAI2, Feng GAO3, Yan-pin ZHANG3, Feng LU research Division of Pharmacology, china Pharmaceutical university, nanjing 210009, china 3Laboratorial Center ofMedicine, southeast university, nanjing 210009, china research Division of Pharmacology China Pharmaceutical University Nanjing 210009 China

AIM: To investigate the effect of CPU86017 on the changes of mRNA abundance of different calcium handling system in infarcted heart. METHODS: Rats were subjected to left coronary ligation to induce myocardial infarc- tion (MI). The treatment with either propranolol (Pro) 5 mg/kg ip or CPU86017 1, 2, and 4 mg/kg ip was initiated on the next day of operation and continued for 20 d. Medication with isoproterenol (Isop) 3 mg/kg sc started on the d 17-21. Ventricular mRNA abundance of ryanodine receptor 2 (RyR2), sarcoplasmic reticulum Ca2+-ATPase (SERCA2), L-type Ca2+ channel, and Na+/Ca2+exchanger (NCX1) were measured. RESULTS: Arrhythmic scores (AS) in the Isop group was raised up to 5.27±1.75 (P3. The AS was depressed by Pro (1.63±1.53, P3.00±1.24, and 1.70±1.85, P<0.01 vs Isop). The significant dispersion of depressed mRNA abundance of RyR2 and SERCA2 was associated with an increase in AS in Isop group, and it was much depressed in the left than the right ventricle. The dispersion and depression of mRNA were restored significantly by Pro and CPU86017, asso- ciated with suppression on AS. In Isop group, the mRNA abundance of L-type Ca2+ channel was not changed; and a moderate increase in the mRNA of NCX1 was seen, the changes were regressed by Pro and CPU86017. CONCLUSION: Isop-induced arrhythmogenesis in MI heart was correlated mainly with a dispersion of depressed mRNA abundance in ventricle likely due to the consequence of PKA over-phosphorylation. A suppression of arrhythmia by Pro and CPU86017 resulted from a regression of the dispersion and depression of RyR2 and SERCA2.

关键词： myocardial infarction isoproterenol arrhythmia calcium 4-chlorobenzyltetrahydroberberine

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 21.096,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