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Cooperative HARQ protocol and diversity analysis of systems with multiple incremental relays

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The Journal of china Universities of Posts and Telecommunications 2009年第5期16卷 8-13页

作者： FAN Bin , WANG Wen-bo, LIN Yi-cheng, ZHENG Kan wireless Signal Processing and network lab, key laboratory of Universal wireless communication, ministry of education, Beijing University of Posts and Telecommunications, Beijing 100876, china wireless Signal Processing and network lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

wireless networks contain an inherent distributed spatial diversity that can be exploited by relays. Relay networks can take advantage of the broadcast-oriented nature of wireless transmission, but require more radio resource to transmit data for their multi-hop traits. Fortunately, incremental relaying technique, which can choose direct or multi-hop transmission adaptively, can efficiently utilize resource. In this article, the incremental transmission with amplify-and-forward （AF） relays is focused on. A practical hybrid-automatic retransmission request （HARQ） protocol is designed, and the related optimal relay selection strategy is proposed. To analyze the cooperative diversity of system with the proposed protocol, the capacity lower bound is deduced. Simulation and analytical results indicate that by adopting the optimal relay selection strategy, the system with the proposed HARQ protocol can achieve an order of cooperative diversity that equals the aggregated number of the relay and source nodes.

关键词： cooperative HARQ AF incremental relay diversity gain

A NEW AD HOC ROUTING ALGORITHM BASED ON MINIMIZING THE CHANNEL HANDOFF

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Journal of Electronics(china) 2010年第6期27卷 749-755页

作者： Xie Jin Zhu Qi Li Zongshou Jiangsu key laboratory of wireless communications Nanjing University of Posts and Telecommunications Nanjing 210003 China） key lab on Wideband wireless communications and sensor network technology of ministry of education Nanjing University of Posts and Telecommunications Nanjing 210003 China National Mobile communications Research laboratory Southeast University Nanjing 210003 China

How to improve the performance of the wireless Ad Hoc network by utilizing the spectrum resources efficiently has become a hot research topic in recent years. In this paper we propose a reactive routing algorithm that supports multiple channels to improve the performance of the Ad Hoc network based on the minimizing of the channel handoff. Our approach allocates the communication channel during the route discovery, and notifies the allocated channel information to the corresponding node in the route reply packets. Each node in the route tries its best to choose the same channel with the upstream node without interference. The simulation results show that our algorithm performs better than the K-hop distinct protocols in both average delays and network throughputs

关键词： Ad Hoc Multi-channel Channel handoff network throughputs Routing

AN IMPROVED EPON UPSTREAM TRANSMISSION SCHEME WITH ZERO INTER-PERIOD IDLE LOSS

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Journal of Electronics(china) 2011年第Z1期 664-669页

作者： Shen Jianhua Guo Hongmei Mi Zhengkun(key lab of Broadband wireless communication and sensor network technology(NUPT),ministry of education,nanjing University of Posts and Telecommunications,nanjing 210003,china)

Existing Ethernet Passive Optical network(EPON) Dynamic Bandwidth Allocation(DBA) algorithms suffer from the disadvantage of idle time loss,which lower the upstream bandwidth *** letter proposes an improved upstream transmission scheme with idle-time eliminating *** analysis and numerical calculation prove that the improved scheme can ef-fectively eliminate the idle time and enhance the efficiency of upstream link *** results have shown that the bandwidth utilization can be raised up to 15% in heavy-load scenarios while the time delay performance of Assured Forwarding(AF) and Best Effort(BE) services are improved simultaneously.

关键词： Ethernet Passive Optical network(EPON) Dynamic Bandwidth Allocation(DBA) algorithm Channel transmission scheme Idle time eliminating

COMPRESSED SPEECH SIGNAL SENSING BASED ON THE STRUCTURED BLOCK SPARSITY WITH PARTIAL KNOWLEDGE OF SUPPORT

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Journal of Electronics(china) 2012年第Z1期 62-71页

作者： Ji Yunyun* ** Yang Zhen** Xu Qian* *(College of communication and Information Engineering, nanjing University of Posts and Telecommunications, nanjing 210003, china) **(key lab of Broadband wireless communication and sensor network technology, ministry of education, nanjing University of Posts & Telecommunications, nanjing 210003, china)

Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper. The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed program and Basis Pursuit (BP). The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals. It is proved by the simulation results of the mixed program which is an improved version of the mixed program. The second one is the well known large DCT coefficients of voiced speech focus on low frequency. In line with this feature, a special Gaussian and Partial Identity Joint (GPIJ) matrix is constructed as the sensing matrix for voiced speech signals. Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults.

关键词： Compressed Sensing (CS) Speech signals Sensing matrix Block sparsity

An efficient ranging method based on Chinese remainder theorem for RIPS measurement

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Science china(Information Sciences) 2010年第6期53卷 1233-1241页

作者： WANG Chen , YIN QinYe & WANG WenJie ministry of education key lab for Intelligent networks and network Security, Xi’an Jiaotong University, Xi’an 710049, china ministry of education key lab for Intelligent networks and network Security Xi"an Jiaotong University

The radio interferometric positioning system(RIPS) measures the phase difference of the interference signal to provide high accuracy and at the same time maintain simple hardware configuration for wireless sensor ***, it suffers from phase ambiguity problem because of the periodicity of phase, which makes it hard to determine the actual distance difference only from a single phase *** solve the problem, RIPS makes multiple measurements at different frequencies so as to determine the distance difference from multiple ***, this is a computationally intensive searching process and not suitable for energyconstrained wireless sensor *** this paper, we introduce the Chinese remainder theorem(CRT) to RIPS to solve the phase ambiguity ***, we utilize some properties of the coefficients in the CRT algorithm to avoid the over-sensitivity of the traditional CRT, which increases the robustness of the *** apply this robust CRT algorithm to the ranging process which calculates the distance difference directly from a closed-form equation and therefore reduces the response time and the energy consumption of the ranging procedure.

关键词： ranging phase ambiguity Chinese remainder theorem robustness energy efficiency wireless sensor networks

TWO-WAY DENOISE-AND-FORWARD network CODING OPPORTUNISTIC RELAYING AIMING AT MINIMIZING EUCLIDEAN DISTANCE IN MULTI-ACCESS PHASE

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Journal of Electronics(china) 2011年第Z1期 433-443页

作者： Jia Xiangdong* ** *** Yang Longxiang* ** Shao Shixiang* ** *(wireless communications key lab of Jiangsu Province,nanjing University of Posts and Telecommunications,nanjing 210003,china) **(key lab of Broadband wireless communication and sensor network technology,ministry of education,nanjing University of Posts and Telecommunications,nanjing 210003,china) ***(College of Mathematics and Information Science,Northwest Normal University,Lanzhou 730070,china)

To exploit the effect of modulation schemes on the best relay selection,a novel Jointing Modulation schemes max-min criterion(JM-max-min) is proposed firstly for Two-Way De-Noise-and-Forward(DNF) Opportunistic Relaying systems(TW-DNF-OR) by aiming at minimizing the Pairwise Error Probability(PEP) of Multi-Access(MA) phase which dominates the error per-formance of TW-DNF-OR due to the presence of MA *** proposed JM-max-min criterion integrates perfectly the minimum distances of constellations and the relay links ***,with the proposed JM-max-min criterion,we analyze the Symbol Error Probabilities(SEPs) of MA phase and BroadCast(BC) phase by using the approximated mathematics analysis,and present the corresponding closed-form expressions to *** numerical analysis shows,for a given modulations combination at both sources,the TW-DNF-OR systems with the proposed JM-max-min criterion outperform the one with the conventional max-min criterion.

关键词： Cooperative communications Opportunistic relaying network coding Max-min crite-rion

Green networking Based Energy Efficient communications

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china communications 2012年第2期9卷 22-30页

作者： Wang Wennai Mi Zhengkun Wang Bin key lab of Broadband wireless communication and sensor network technology(nanjing University of Posts andTelecommunications) Nanjing 210003P.R.China

The mainstream approaches to green networking are discussed first from the view of engineering,including resource consolidation,server virtualization,selective connectedness,and proportional computing.A brief introduction to network virtualization techniques is given then and a virtual node embedding approach is ***,three kinds of enhanced green networking schemes by network virtualization are proposed,that is enhancement to sever virtualization,resource consolidation and Adaptive Link Rate(ALR).Examples are included to show the virtue of network virtualization to green networking in terms of energy efficient communications.

关键词： energy efficient communications greennetworking network virtualization green of Infor-mation and communications technology (ICT)

Image Hiding Algorithm in Discrete Cosine Transform Domain Based on Grey Prediction and Grey Relational Analysis

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china communications 2013年第7期10卷 57-70页

作者：黄海平黄世超陈九天王汝传 College of Computer Nanjing University of Posts and Telecommunications Jiangsu High technology Research key laboratory for wireless sensor networks key laboratory of Broadband wireless communication and sensor network technology of ministry of education Nanjing University of Posts and Telecommunications Jiangsu Provincial key laboratory for Computer Information Processing technology Soochow University

Traditional information hiding algorithms cannot maintain a good balance of capacity,invisibility and *** this paper,a novel blind colour image information hiding algorithm based on grey prediction and grey relational analysis in the Discrete Cosine Transform(DCT) domain is ***,this algorithm compresses the secret image losslessly based on the improved grey prediction GM(1,1)(IGM) *** then chooses the blocks of rich texture in the cover image as the embedding regions using Double-dimension Grey Relational Analysis(DGRA).Finally,it adaptively embeds the compressed secret bits stream into the DCT domain mid-frequency coefficients,which are decided by those blocks' Double-Dimension Grey Correlation Degree(DGCD) and Human Visual System(HVS).This method can ensure an adequate balance between invisibility,capacity and *** results show that the proposed algorithm is robust against JPEG compression(46.724 6 dB when the compression quality factor is 90%),Gaussian noise(45.531 3 dB when the parameter is(0,0.000 5)) etc.,and it is a blind information hiding algorithm that can be extracted without an original carrier.

关键词： image information hiding IGM DGRA blind information hiding DCT

Ether net Ring Protection for ITU-T G.8032

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china communications 2012年第11期9卷 87-97页

作者： Wang Bin Wang Wennai College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China key laboratory of Broadband wireless communication and sensor network technology (nanjing University of Posts and Telecommunications) Ministry of Education Nanjing 210003 P. R. China

Ethernet Ring Protection (ERP) introduced by ITU-T G.8032 Recommendation is a new type of packet-switched network protection technology, which can provide ring automatic protection switch. However, the Filtering Database (FDB) flush method adopted in the current ERP standard has the drawback of introducing a large amount of transient traffic overshoot caused by flooded Ethernet frames right after protection switching. In this article, we propose a G.8032 ERP scheme that uses FDB flush based on area to resolve this issue and investigate how the proposed scheme deals with the traffic flooding problem. The theoretical analysis and simulation show that the proposed scheme can effectively improve the performance of the Ethernet ring by decreasing the unnecessary FDB flush in comparison with the existing approaches.

关键词： carrier ethernet ERP FDB flush markov chain