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Color Context Binary Pattern Using Progressive Bit Correction for Image Classification

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Chinese Journal of Electronics 2021年第3期30卷 471-481页

作者： song tiecheng FENG Jie LI Shuang ZHANG Tianqi School of Communication and Information Engineering Chongqing University of Posts and Telecommunications

Local binary pattern(LBP) is sensitive to noise. Noise-resistant LBP(NRLBP) addresses this problem by thresholding local neighboring pixels into three-valued states(i.e., 0, 1 and uncertain bits)and recovering uncertain bits via an error-correction mechanism. In this paper, we extend NRLBP to deal with color images and propose a robust color image descriptor called Color context binary pattern(CCBP). In CCBP, we employ scale context and neighbor context to progressively correct the encoded bits. First, we encode intra-channel local neighboring pixels into three-valued states in scale space and use majority voting to correct all states across scales. Then, we compute inter-channel color feature distances and correct the uncertain bits via neighboring bit propagation. Finally, we construct the image descriptor by concatenating all histograms based on the corrected binary codes. Experiments on four benchmark databases demonstrate the robustness of CCBP for color image classification under very low signal-to-noise ratio levels.

关键词： scale context intra-channel local neighboring pixels image classification color images corrected binary codes color image classification feature extraction local binary pattern bit propagation NRLBP three-valued states CCBP image coding binary codes progressive bit correction error correction codes uncertain bits Color context binary pattern neighbor context inter-channel color feature distances robust color image descriptor image texture error-correction mechanism noise-resistant LBP image colour analysis encoded bits

Non-reconstruction compressive detector for wideband spectrum sensing based on GLRT

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The Journal of China Universities of Posts and Telecommunications 2018年第4期25卷 19-27页

作者： song Xiaoqin Jin Hui Tan Yazhu Hu Jing song tiecheng College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNaujing 210016China School of Information Science and Engineering Southeast UniversityNanjing 210096China

Spectrum sensing is an essential ability to detect spectral holes in cognitive radio( CR) networks. The critical challenge to spectrum sensing in the wideband frequency range is how to sense quickly and accurately. Compressive sensing( CS) theory can be employed to detect signals from a small set of non-adaptive,linear measurements without fully recovering the signal. However,the existing compressive detectors can only detect some known deterministic signals and it is not suitable for the time-varying amplitude signal,such as spectrum sensing signals in CR networks. First,a model of signal detect is proposed by utilizing compressive sampling without signal recovery,and then the generalized likelihood ratio test( GLRT) detection algorithm of the time-varying amplitude signal is derived in detail. Finally, the theoretical detection performance bound and the computation complexity are analyzed. The comparison between the theory and simulation results of signal detection performance over Rayleigh and Rician channel demonstrates the validity of the performance bound. Compared with the reconstructed spectrum sensing detection algorithm,the proposed algorithm greatly reduces the data volume and algorithm complexity for the signal with random amplitudes.

关键词： CR wideband spectrum sensing CS GLRT time-varying amplitude

Traffic-Adaptive Proactive Spectrum Handoff Strategy for Graded Secondary Users in Cognitive Radio Networks

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Chinese Journal of Electronics 2015年第4期24卷 844-851页

作者： ZHANG Lei song tiecheng WU Ming BAO Xu GUO Jie HU Jing National Mobile Communications Research Laboratory Southeast University School of Computer Science and Communication Engineering Jiangsu University

In order to meet different delay requirements of various communication services in Cognitive radio(CR) networks, Secondary users(SUs) are divided into two classes according to the priority of accessing to spectrum in this paper. Based on the proactive spectrum handoff scheme, the Preemptive resume priority(PRP) M/G/1queueing is used to characterize multiple spectrum handoffs under two different spectrum handoff strategies. The traffic-adaptive spectrum handoff strategy is proposed for graded SUs so as to minimize the average cumulative handoff delay. Simulation results not only verify that our theoretical analysis is valid, but also show that the strategy we proposed can reduce the average cumulative handoff delay evidently. The effect of service rate on the proposed spectrum switching point and the admissible access region are provided.

关键词： Cognitive radio network Cumulative handoff delay Graded secondary users Admissible access region

Study and simulation of video communications under wireless environment based on blind source separation

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Frontiers of Electrical and Electronic Engineering in China 2008年第4期3卷 418-424页

作者： Jie GUO Lianfeng SHEN tiecheng song Zhihui YE Department of Electric Engineering Hohai UniversityNanjing 210098China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

A new scheme is proposed to separate several compressed video signals transferred in multiple wireless channels using the blind source separation *** scheme selects IEEE 802.11b and XVID compression as the wireless communications channel and MPEG-4 video compression,respectively.A simulation model is then made for the video communications under a wireless *** model can separate several video sig-nals using blind source *** show that the normalized whiten plus cyclic whiten based on cyclo-stationary(NWCW-CS)algorithm based upon the cyclo-stationary characteristics of signals has the best separation performance and fast ***,the algorithm can solve the mixing of video *** image of the transferred video signals decompressed by XVID is nearly consistent with the source *** new method meets the requirement of real-time video communications.

关键词： blind source separation cyclostationary video MPEG-4 wireless local area network

THE POINCAR BIFURCATION OF CUBIC HAMILTONIAN SYSTEMS WITH DOUBLE CENTERS

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Annals of Differential Equations 2005年第3期21卷 349-352页

作者： Liu tiecheng song Yan Dept. of Math. Bohai University Jinzhou 121000

In this paper, we discuss the Poincaré bifurcation of cubic Hamiltonian systems with double centers and prove that the systems may at least generate two limit cycles and at most generate three limit cycles outside th... 详细信息

关键词： cubic Hamiltonian system Poincaré bifurcation limit cycle

Physical-layer security enhancement method for wireless HetNets via transmission pair scheduling

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Journal of Southeast University(English Edition) 2019年第3期35卷 318-324页

作者： Ding Xiaojin song tiecheng Zhang Gengxin Jiangsu Engineering Research Center of Communication and Network Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096

In order to enhance the physical-layer security of wireless transmission in a wireless heterogeneous network (HetNet), a two-stage-based cooperative framework is advocated. To be specific, a source-destination (SD) pair is opportunistically chosen at the beginning of the transmission slot, which can be used to assist the transmissions of other SD pairs. Under this framework, a transmit antenna selection assisted opportunistic SD pair scheduling (TAS-OSDS) scheme is proposed, and the intercept probability (IP) of the proposed TAS-OSDS, the conventional round-robin source-destination pair scheduling (RSDS) and the conventional non-cooperation (non-coop) schemes is also analyzed, where the RSDS and non-coop schemes are used for comparison with the proposed TAS-OSDS. Numerical results show that increasing the number of the SD pairs can effectively reduce the IP of the TAS-OSDS scheme, whereas the IP of the RSDS and the non-coop remain unchanged with an increasing number of the SD pairs. Furthermore, the TAS-OSDS scheme achieves a lower IP than that of the RSDS and the non-coop schemes, showing the superiority of the proposed TAS-OSDS.

关键词： wireless heterogeneous network physical-layer security source-destination pair scheduling

A game-theory approach against Byzantine attack in cooperative spectrum sensing

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Journal of Southeast University(English Edition) 2018年第4期34卷 423-429页

作者： Wu Jun song tiecheng Yu Yue Hu Jing School of Information Science and Engineering Southeast UniversityNanjing 211189China

In order to solve the Byzantine attack problem in cooperative spectrum sensing,a non-cooperative game-theory approach is proposed to realize an effective Byzantine ***,under the framework of the proposed non-cooperative game theory,the pure Byzantine attack strategy and defense strategy in cooperative spectrum sensing are analyzed from the perspective of the Byzantine attacker and network *** cost and benefit of the pure strategy on both sides are defined. Secondly,the mixed attack and defense strategy are also derived. The closed form Nash equilibrium is obtained by the Lemke-Howson algorithm. Furthermore,the impact of the benefit ratio and penalty rate on the dynamic process of the noncooperative game is analyzed. Numerical simulation results show that the proposed game-theory approach can effectively defend against the Byzantine attack and save the defensive cost.

关键词： cooperative spectrum sensing Byzantine attack game theory non-cooperative game Nash equilibrium

Resource allocation for NOMA-based vehicular communications

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Journal of Southeast University(English Edition) 2020年第1期36卷 8-13页

作者： Jiang Wei song tiecheng Wang Cong Hu Jing National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

To solve fast channel variations induced by the mobility of the vehicles and achieve effective and reliable vehicular communications,the non-orthogonal multiple access is applied to the vehicle to vehicle(V2V)pairs underlaid vehicle to infrastructure(V2I)users to solve the downlink resource allocation.A geographic position-based clustering algorithm for V2V users is *** base station preassigns the channel resources and the Kuhn-Munkres algorithm is used to complete the channel ***,the verified particle swarm optimization(PSO)is adopted to achieve the optimal power *** simulation results show that the proposed scheme outperforms the existing device to device(D2D)mechanism by improving the network connectivity,spectrum efficiency and data transmission rate.

关键词： non-orthogonal multiple access vehicle to vehicle vehicle to infrastructure subchannel assignment power control

A cooperative spectrum sensing results transmission scheme with LT code based on energy efficiency priority

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Journal of Southeast University(English Edition) 2018年第4期34卷 444-450页

作者： song Xiaoqin Jin Hui Tan Yazhu Hu Jing song tiecheng College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Information Science and Engineering Southeast UniversityNanjing 210096China

To deal with a sharp increase in transmission energy consumption due to the presence of a large number of secondary users( SUs),an energy-efficient cooperative spectrum sensing results transmission scheme is proposed for cognitive radio systems. First,a cluster-based structure is introduced into the sensing results transmission scheme to reduce the transmission power. Then,the centralized sensing results transmission model is employed,and the non-fixed code rate Luby transform( LT)code is selected as the channel coding since its code rate can dynamically adapt to channel conditions and therefore avoid unnecessary redundancy in the transmission ***,an improved optimal degree distribution( ODD)is designed for the LT code. The simulation results show that the choice of the appropriate parameters in degree distribution is very helpful for the LT code to achieve a promising performance. The ODD with optimized parameters can achieve more than 2 d B performance gain than other typical degree distributions when the bit error rate( BER) is 10-3. The energy consumption of the proposed scheme is not only at least71. 4% lower than that of the non-coding system,but also lower than that of the convolutional coding system with different code rates. Meanwhile, the energy consumption can be further reduced in the case that a suitable clustering method is selected.

关键词： cooperative spectrum sensing energy-efficient cluster-based Luby transform (LT) code degree distribution