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Novel error resilient tag estimation for RFID system in interference scenarios

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 116-121页

作者： WANG Shuai HONG Wei-jun PENG Biao LI Shu-fang school of information and communication engineering Beijing University of Posts and Telecommunications

In a radio frequency identification （RFID） system, the backscattered signal is small and prone to interference. The performance of RFID tag identification in interference scenarios is degraded compared to that in error-free scenarios. In this paper, a novel Mahalanobis distance estimate （MDE） method is proposed to jointly estimate the number of tags and packet error rate （PER）. The MDE method is error resilient owing to its ability to achieve a stable estimation when interference is impairing the observed information. The proposed method achieves significantly enhanced accuracy over existing methods by taking all the information and correlations among the observed results into account. The MDE method improves the estimate performance based on efficient decorrelation and classification of the observed information. Moreover, the performance of the PER estimate is analyzed both in theory and through simulations. It can be concluded from the analysis that the estimated PER is unbiased and variance-bounded. Simulations show that the proposed estimate outperforms the previous proposals in terms of accuracy and stability, which makes it suitable for application in interference scenarios.

关键词： RFID tag estimate PER estimate

Reputation-based secure spectrum situation fusion in distributed cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 110-117页

作者： Li Fangwei Liu Fan Zhu Jiang Nie Yifang school of communication and information engineering Chongqing University of Posts and Telecommunications

In distributed cognitive radio （CR） network, the cooperative spectrum situation sensing based on consensus scheme may be disrupted by spectrum sensing data falsification （SSDF） attacks. In this paper, a secure spectrum situation fusion scheme based on reputation is proposed to counter attacks. The neighboring nodes of secondary users （SUs） get the corresponding dynamic trust value according to their behavior, which restrict the impact of the malicious behavior on the premise to ensure information interaction of normal nodes. Theoretical analysis and simulation results show that the consensus fusion scheme based on reputation has better performance than the existing algorithm which eliminates the neighboring node with the biggest deviation value from mean value. It demonstrates that the proposed scheme not only achieves better convergence properties but also has higher detection probability than the existing scheme in the process of spectrum situation fusion.

关键词： cognitive radio spectrum situation fusion secure consensus spectrum sensing data falsification (SSDF) attack

Classification-based self-adaptive differential evolution and its application in multi-lateral multi-issue negotiation

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Frontiers of Computer Science 2012年第4期6卷 442-461页

作者： Xiaojun BI Jing XIAO school of information and communication engineering Harbin Engineering UniversityHarbin 150001China school of information engineering Liaoning Provincial College of CommunicationsShenyang 110122China

Multi-lateral multi-issue negotiations are the most complex realistic negotiation problems. Automated ap- proaches have proven particularly promising for complex ne- gotiations and previous research indicates evolutionary com- putation could be useful for such complex systems. To im- prove the efficiency of realistic multi-lateral multi-issue ne- gotiations and avoid the requirement of complete informa- tion about negotiators, a novel negotiation model based on art improved evolutionary algorithm p-ADE is proposed. The new model includes a new multi-agent negotiation protocol and strategy which utilize p-ADE to improve the negotia- tion efficiency by generating more acceptable solutions with stronger suitability for all the participants. Where p-ADE is improved based on the well-known differential evolution （DE）, in which a new classification-based mutation strategy DE/rand-to-best/pbest as well as a dynamic self-adaptive pa- rameter setting strategy are proposed. Experimental results confirm the superiority of p-ADE over several state-of-the-art evolutionary optimizers. In addition, the p-ADE based multi- agent negotiation model shows good performance in solving realistic multi-lateral multi-issue negotiations.

关键词： differential evolution global optimum e-commerce agent multi-lateral multi-issue negotiation

Convergence analysis and performance optimization of parallel concatenated systematic polar code

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维普期刊数据库

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The Journal of China Universities of Posts and Telecommunications 2018年第2期25卷 1-9页

作者： Liu Zhenzhen Niu Kai Dong Chao Lin Jiaru school of information and communication engineering Beijing University of Posts and Telecommunications

Similar to the analysis of Turbo codes, the parallel concatenated systematic polar code （PCSPC） can also be analyzed by the extrinsic information transfer （EXIT） chart. The convergence of the iterative decoding based on soft cancellation （SCAN） and belief propagation （BP） of PCSPC are analyzed by the EXIT chart. Analysis shows that SCAN decoder is more appropriate than BP decoder for this iterative decoding structure in terms of complexity. In addition, the weight coefficients of the iterative decoding structure are optimized by the simulated-EXIT （S- EXIT） chart, which improves the performance of PCSPC.

关键词： PCSPC EXIT chart SCAN decoder BP decoder weight coefficient

Energy-efficiency based downlink multi-user hybrid beamforming for millimeter wave massive MIMO system

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The Journal of China Universities of Posts and Telecommunications 2016年第4期23卷 53-62页

作者： Jiang Jing Cheng Xiaoxue Xie Yongbin school of communication and information engineering Xi'an University of Posts and Telecommunications

The fifth generation mobile communication（5G） systems can provide Gbit/s data rates from massive multiple-input multiple-output（MIMO） combined with the emerging use of millimeter wavelengths in small heterogeneous cells. This paper develops an energy-efficiency based multi-user hybrid beamforming for downlink millimeter wave（mm Wave） massive MIMO systems. To make better use of directivity gains of the analog beamforming and flexible baseband processing of the digital beamforming, this paper proposes the analog beamforming to select the optimal beam which can maximize the power of the objective user and minimize the interference to all other users. In addition, the digital beamforming maximizes the energy efficiency of the objective user with zero-gradient-based approach. Simulation results show the proposed algorithm provide better bit error rate（BER） performance compared with the traditional hybrid beamforming and obviously improved the sum rate with the increase in the number of users. It is proved that multi-user MIMO（MU-MIMO） can be a perfect candidate for mm Wave massive MIMO communication system. Furthermore, the analog beamforming can mitigate the inter-user interference more effectively with the selection of the optimal beam and the digital beamforming can greatly improve the system performance through flexible baseband processing.

关键词： 5G systems mm Wave massive MIMO MU-MIMO analog beamforming digital beamforming hybrid beamforming

Cooperative Spectrum Sensing over Generalized Fading Channels Based on Energy Detection

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China communications 2018年第5期15卷 128-137页

作者： He Huang Chaowei Yuan school of information and communication engineering Beijing University of Posts and Telecommunications

This paper analyzes the unified performance of energy detection(ED) of spectrum sensing(SS) over generalized fading channels in cognitive radios(CRs). The detective performance of SS will be obviously affected by fading channels among communication nodes, and ED has the advantages of fast implementation, no requirement of priori received information and low complexity, so it is meaningful to investigate ED over various fading channels. The probability density function(p.d.f.) of α-κ-μ distribution is derived to evaluate energy efficiency for sensing *** detection probability with Marcum-Q function has been derived and the close-form expressions with moment generating function(MGF) method are deduced to achieve ***, exact closed-form analytic expressions for average area under the receiver operating characteristics curve( AUC) also have been deduced to analyze the performance characteristics of ED over α-κ-μ fading ***, cooperative spectrum sensing(CSS) with diversity reception has been applied to improve the detection accuracy and mitigate the shadowed fading features with OR-rule. At last, the results show that the detection capacity of ED will be evidently affected by α-κ-μ fading channels, but appropriate channel parameters can improve sensing performance. In addition, the establishedED-fading pattern is approved by simulations,and it can significantly enhance the detection performance of proposed algorithms.

关键词： energy detection cooperativesensing α-κ-μ distribution receiver diversity

Resource allocation for the cluster-based cooperative multicast in OFDM-based cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 1-7,33页

作者： ZHANG Shuang-lu XU Wen-jun LI Sheng-yu LIN Jia-ru school of information and communication engineering Beijing University of Posts and Telecommunications

This paper investigates the resource allocation problem for the cluster-based cooperative multicast in orthogonal frequency division multiplexing （OFDM）-based cognitive radio （CR） systems. Aiming at maximizing the system sum rate, an efficient clustering scheme is proposed. It begins with the clustering phase where secondary users （SUs） with good channel conditions are selected as cluster heads, while others decide to which cluster they belong. When the clusters are organized, it turns to a two-stage data transmission phase： in stage 1, the secondary＇ base station （BS） transmits data to the cluster heads; in stage 2, the cluster heads forward the received data to their cluster members. Based on this scheme, a joint subcarrier and power allocation algorithm is proposed. Simulation results show that the proposed scheme significantly outperforms the conventional multicast （CM） as well as the multiple description coding multicast 0VIDCM） in terms of the system sum rate.

关键词： cooperative multicast cognitive radio OFDM cluster

Design and evaluation of V2X communication system for vehicle and pedestrian safety

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The Journal of China Universities of Posts and Telecommunications 2015年第6期22卷 18-26页

作者： Liu Zhenyu Pu Lin Zhu Konglin Zhang Lin school of information and communication engineering Beijing University of Posts and Telecommunications

As the vehicles gain the extensive popularity and increasing demand, traffic accident is one of the most serious problems faced by modem transportation system. Hereinto, crashes between cars and pedestrians cause plenty of injuries and even death. Diverting attention from walking to smartphones is one of the main reasons for pedestrians getting injured by vehicles. However, the traditional measures protecting pedestrians from the vehicles heavily rely on the sound warning method, which do not capable for pedestrians focusing on the smartphones. As the smartphones become ubiquitous and intelligent, they have the capacity to provide alert for the pedestrians with the help of vehicle-to-pedestrian （V2P） communication. In this paper, an efficient vehicle-to-X （V2X） communication system is designed for the vehicle and pedestrian communication to guarantee the safety of people. It achieves the IEEE 802.11p and the WiFi protocols meanwhile on the on-board unit （OBU） designed for vehicles. Extensive evaluation shows that the OBU can provide the reliable communication for vehicle-to-vehicle （V2V） and V2P in terms of packet delivery rate and average delay. Furthermore, two safety applications have been developed to protect the safety of vehicles and pedestrians based on the data transferred from the OBU. The first application is designed to show the driving information and provide the collision forewaming alert on the tablet within the vehicle. The second application is developed for the smartphone to provide forewarning alert information to the smartphone-distracted vulnerable pedestrians. Smartphone states are appreciable to provide the adaptive alert modes. Experimental results show that these applications are capable of alerting the intersection accidents, and the pedestrians can get the adaptive alerts according to smartphone usage contexts.

关键词： V2X communication system pedestrian safety vehicle safety on board unit smartphone collision forewarning +

A New RFID Anti-collision Algorithm Based on the Q-Ary Search Scheme

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Chinese Journal of Electronics 2015年第4期24卷 679-683页

作者： SU Jian WEN Guangjun HONG Danfeng school of communication and information engineering University of Electronic Science and Technology of China College of information engineering Qingdao University

Deterministic tree-based algorithms are mostly used to guarantee that all the tags in the reader field are successfully identified, and to achieve the best performance. Through an analysis of the deficiencies of existing tree-based algorithms, a Q-ary search algorithm was proposed. The Q-ary search(QAS) algorithm introduced a bit encoding mechanism of tag ID by which the multibit collision arbitration was implemented. According to the encoding mechanism, the collision cycle was reduced. The theoretical analysis and simulation results showed that the proposed MS algorithm overcame the shortcoming of existing tree-based algorithms and exhibited good performance during identification.

关键词： Radio frequency identification(RFID) Anti-collision Encoding Energy efficiency