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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

维普期刊数据库

Non-blocking message total ordering protocol

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Science in China(Series F) 2008年第12期51卷 1919-1934页

作者： WANG Yun & WANG JunLing School of Computer Science & Engineering, Southeast University Key lab of Computer network & Information Integration, moe, Nanjing 210096, China School of Computer Science & Engineering Southeast University Key lab of Computer network & Information Integration MOE Nanjing China

Message total ordering is a critical part in active replication in order to maintain consistency among members in a fault tolerant group. The paper proposes a non-blocking message total ordering protocol （NBTOP） for distributed systems. Non-blocking property refers to that the members in a fault tolerant group keep on running independently without waiting for installing the same group view when a fault tolerant group evolves even when decision messages collide. NBTOP takes advantage of token ring as its logical control way. Members adopt re-requesting mechanism （RR） to obtain their lost decisions. Forward acknowledgement mechanism （FA） is put forth to solve decision collisions. The paper further proves that NBTOP satisfies the properties of total order, agreement, and termination. NBTOP is implemented, and its performance test is done. Comparing with the performance of Totem, the results show that NBTOP has a better total ordering delay. It manifests that non-blocking property helps to improve protocol efficiency.

关键词： total ordering protocol non-blocking active replication fault tolerance token ring

维普期刊数据库

AOD estimation in WSN localization system with synthetic aperture technique

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Science China(Information Sciences) 2012年第10期55卷 2216-2225页

作者： WANG WenJie,YAO BoBin & YIN QinYe moe Key lab for Intelligent networks and network Security,School of Electronic and Information Engineering,Xi’an Jiaotong University,Xi’an 710049,China moe Key lab for Intelligent networks and network Security School of Electronic and Information Engineering Xi’an Jiaotong University Xi’an China

Angel of departure(AOD) based distributed localization scheme in wireless sensor networks allows the single antenna sensor node to estimate its own AOD information by an equivalent antenna array for further position ***,the condition that the number of antennas at the multi-antenna agent/anchor node should be larger than the number of multipath signal components(MPCs) constrains its actual *** this paper,we provide a more practical approach to achieve AOD information estimation under multipath *** that the sensor node can not identify the line of sight(LOS) signal component due to the insufficient degree of freedom,which is determined by the above limiting condition,we introduce a synthetic aperture technique with the aid of a fast moving multi-antenna agent/anchor *** operation greatly enlarges the degree of freedom of the equivalent antenna array constructed at sensor node end but without requiring other extra physical antennas equipped at agent/anchor node or sensor node end,which means that it relaxes the limiting ***,the AOD information of LOS signal component can be estimated and extracted successfully in complex multipath *** analysis proves the effectiveness of our proposed synthetic aperture technique and numerical simulations show great performance improvement.

关键词： angle of departure degree of freedom synthetic aperture wireless sensor networks

THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE SUPPRESSION IN MB-OFDM COGNITIVE RADIOS

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THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE ...

Output Feedback Robust MPC Based-on Direct Input-Output Model

2009 IEEE International Conference on Communication Technology and Applications（ICCTA2009）

作者： Zhigang Xu Cheng Yang Weixia Zou Zheng Zhou Key lab of Universal wireless Communications moe.wireless network lab Beijing University of Posts and Telecommunications Beijing 100876 China

＜正＞From the mathematic expression,we can see that sidelobe power of multi-band orthogonal frequency-division multiplexing（MB-OFDM） signal is a function of the data symbols loaded on the *** the derivation of the minimum of the function,relationships among data symbols, which help to suppress sidelobes,are *** types of methods,referred as Sub-carrier Adding（SA） method and Sub-carrier Multiplying（SM） method, are proposed,which realize the relationships at the cost of small degradation in information transmission *** a result,with the proposed methods,the sidelobe power can be *** results also prove this.

关键词： OFDM sidelobe suppression data symbols relationships

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Output Feedback Robust MPC Based-on Direct Input-Output Mode...

Enhancement and Evolution of TD-SCDMA Systems

第24届中国控制与决策会议

作者： Baocang Ding the Ministry of Education Key lab For Intelligent networks and network Security (moe KLINNS lab)

This paper proposes a synthesis approach to output feedback robust model predictive control （RMPC） for systems with both polytopic description and bounded noise. Unlike previous works, we do not utilize the state space model. Hence, there is no requirement for estimating the bounds on the true state. We directly utilize the input-output model. The feedback control law is based on the current output, past outputs and past inputs. By on-line implementation of the controller, the output and input of the closed-loop system will converge to a neighborhood of the equilibrium point. A numerical example is given to illustrate the effectiveness of the controller.

关键词： Model predictive control Output feedback Input-output model Uncertain systems

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ZTE Communications 2007年第3期5卷 36-43页

作者： Peng Mugen Li Yong Wang Wenbo (wireless Signal Processing and network lab,Beijing University of Posts and Telecommunications,Beijing 100876,China)

Time Division-Synchronous Code Division Multiple Access (TD-SCDMA),a home-grown standard for the third generation mobile communications,is already mature and ready for commercial deployment. The enhancement and evolution of the TD-SCDMA system is a hot topic recently. Many strategies for TD-SCDMA enhancements and evolutions have been proposed,but there are no integrated solutions that can jointly consider the development both in the short term and in the long term. This paper discusses four evolution phases,which are proposed according to the key technologies. Phase 1 is about the current TD-SCDMA system. Phase 2 is the short term evolution of TD-SCDMA,i.e.,the period of HSxPA,including the evolution of High Speed Downlink Packet Access (HSDPA),High Speed Uplink Packet Access (HSUPA) and High Speed Packet Access plus (HSPA+). Phase 3 is the Long Term Evolution (LTE). Phase 4 is the Beyond 3G (B3G)/Fourth Generation (4G) mobile communication Time Division Duplex (TDD) system,which is based on TD-SCDMA. Key characters for every evolution phase are discussed,as well as the advanced technologies adopted in the evolution process such as Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM).

关键词： SCDMA Access TD Enhancement and Evolution of TD-SCDMA Systems

维普期刊数据库

Beamforming based decode-and-forward cooperation via backward synchronization

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Science China(Information Sciences) 2012年第4期55卷 805-814页

作者： LI YuBo,YIN QinYe & WANG Chen 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 Xi’an China

In this paper,a beamforming (BF) based cooperation scheme with decode-and-forward (DF) protocol is proposed and its performance analysis is ***,to solve the issue of carrier synchronization in distributed networks,a backward synchronization (B-Sync) method is introduced,where participating relays synchronize to the reference carrier broadcast by the destination and make signals superimposed coherently at the destination without any phase ***,based on B-sync,a cooperation scheme with DF protocol is proposed to carry out BF forwarding among *** outage probability of this scheme is derived and analyzed,which shows that the full diversity order can be achieved by the proposed ***,symbol error probability (SEP) analysis is presented to evaluate the practical *** results validate the analysis,and show that the proposed scheme outperforms other existing ones in terms of outage probability and SEP.

关键词： cooperative diversity distributed beamforming outage probability symbol error probability decode-and-forward

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 Xi’an China

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

Outage-optimal relaying through opportunistic hybrid forward cooperation

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Science China(Information Sciences) 2011年第6期54卷 1264-1273页

作者： LI YuBo , YIN QinYe & WANG JunSong 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 Xi’an China

In this paper, a new scheme based on relay selection and data forwarding in multi-relay cooperative networks is introduced. Unlike most existing solutions focused on amplify-and-forward (AF) or decode-and-forward (DF) protocol separately, the proposed hybrid forward (HF) scheme takes advantage of both AF and DF protocols in relay forwarding. Based on theoretical analysis, a closed-form expression for the tight lower bound of its outage probability is derived, and further performance analysis is also presented. Then, in total power restricted networks, an optimal power allocation strategy between the source and the selected relay is developed to minimize the outage probability. Simulations are carried out finally, which validate the analysis and show that the HF scheme outperforms other existing ones in terms of outage probability.

关键词： cooperative diversity opportunistic cooperation outage probability power allocation diversity-multiplexing-tradeoff