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PERFORMANCE ANALYSIS OF USER FAIR-BASED RELAY ADAPTIVE POWER ALLOCATION IN PHYSICAL-LAYER NETWORK CODING COOPERATION

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Journal of Electronics(China) 2012年第5期29卷 383-391页

Network Coding (NC) is an effective technology to enhance the cooperative system spectral efficiency. However, since it is network-oriented, the existing performance metric of single-user outage can not comprehensively evaluate its gain and the impact to the entire network, which affect the user fairness. This paper proposes two novel user fair-based adaptive relay power allocation algorithms in single-relay NC cooperative multiple access channels. Firstly, common outage probability is employed as the performance metric, and to minimize it, a specific condition is deduced. On this basis, the instantaneous channel information-based adaptive relay power allocation scheme and the channel statistic information-based one with lower complexity are designed respectively, which make users' signals superimposed at accurately calculated proportion to maintain fairness. Simulation results show that compared with other existing schemes, the proposed schemes can best maintain user fairness, and effectively improve the common outage performance of the whole system, at the expense of small spectral efficiency.

关键词： Power allocation Cooperation Network Coding (NC) Common outage probability User fairness

JOINT LLR-CRC ERROR MITIGATION FOR TWO-WAY ADAPTIVE DENOISE-AND-FORWARD NETWORK CODING

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Journal of Electronics(China) 2013年第4期30卷 352-361页

作者： cheng yulun Yang Longxiang Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications

Network Coding (NC) brings correlation between the coded signals from different sources, which makes the system more vulnerable to the decode error at relay. Conventional Cyclic Redundancy Code (CRC) has been implemented for error bit detection. However, its error correction is simply ignored. To fully exploit this feature, this paper proposes a novel joint Log-Likelihood Ratio (LLR) CRC error mitigation for NC two way relay channel. Specific thresholds are designed to estimate the error number of data block and identify those which can be recovered if the number is within the error correction scope of CRC. We examine two modes of the thresholds, one based on the average Bit Error Rate (BER) of source-relay link, while the other based on that of instantaneous one. We provide the full analysis for the Pair-wise Error Probability (PEP) performance of the scheme. A variety of numerical results are presented to reveal the superiority of the proposed scheme to conventional CRC NC under independent Rayleigh fading channels. Moreover, the efficiencies of the proposed thresholds are also validated.

关键词： Network Coding (NC) Log-Likelihood Ratio (LLR) Cyclic Redundancy Code (CRC) Denoise-and-forward Pair-wise Error Probability (PEP)

Joint Caching and User Association for Energy Harvesting Aided Internet of Things with Full-Duplex Backhauls

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Journal of Communications and Information Networks 2021年第4期6卷 420-428页

作者： yulun cheng Wenchao Xia Haitao Zhao Longxiang Yang Hongbo Zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

Due to its wide coverage,stable link,and low latency,cellular network has become one of the main access networks for Internet of things(IoT).However,the expenses of backhauls and node charging grow fast with the number of *** this issue,this paper addresses the joint caching and user association for energy harvesting aided IoT with full-duplex *** formulate the node charging,full-duplex base station association,and cache allocation by using Stackelberg *** the structural characteristics are utilized to decompose the model into a two-layer knapsack *** the basis of that,an alternative direction iteration is proposed,which firstly compresses the solution space by the constraints,and then obtains the optimization results by alternative *** results verify the effectiveness of the proposed algorithm in utility improvement and cost reduction.

关键词： Internet of things full-duplex energy harvesting network caching Stackelberg game

Excitonic devices based on two-dimensional transition metal dichalcogenides van der Waals heterostructures

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 41-67页

作者： yulun Liu Yaojie Zhu Zuowei Yan Ruixue Bai Xilin Zhang Yanbo Ren Xiaoyu cheng Hui Ma Chongyun Jiang College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China School of Physical Science and Technology Tiangong UniversityTianjin 300387China

Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices.

关键词： excitonic devices van der Waals heterostructures transition metal dichalcogenides interlayer excitons valley-Hall effect optoelectronics

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联合部分干扰抵消的TD集群多小区联合检测

数据采集与处理 2012年第5期27卷 541-546页

作者：成聿伦杨龙祥南京邮电大学江苏省无线通信重点实验室南京210003 南京邮电大学宽带无线通信与传感网技术教育部重点实验室南京210003

针对TD集群下行智能天线无法使用,链路小区间干扰严重的问题,提出了将判决反馈与单小区联合检测通过部分干扰抵消进行级联的方案消除干扰。通过重新排列总系统矩阵,消除了多反馈级数带来的错误积累,提高了反馈精度,其单小区JD部分避免... 详细信息

针对TD集群下行智能天线无法使用,链路小区间干扰严重的问题,提出了将判决反馈与单小区联合检测通过部分干扰抵消进行级联的方案消除干扰。通过重新排列总系统矩阵,消除了多反馈级数带来的错误积累,提高了反馈精度,其单小区JD部分避免了扩展矩阵维数,从而减弱了算法对背景噪声的放大效应。比较了其与传统算法的抗小区间干扰能力以及算法复杂度,仿真结果验证了该方案的有效性及在各种信道下的鲁棒性。

关键词：集群系统小区间干扰联合检测干扰抵消

基于预失真的异步物理层网络编码相位纠正算法

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高技术通讯 2015年第8期25卷 766-774页

作者：成聿伦杨龙祥南京邮电大学江苏省无线通信重点实验室南京210003 南京邮电大学教育部宽带无线通信与传感网技术重点实验室南京210003

研究了异步物理层网络编码(PLNC)系统中的载波相位偏移问题,提出一种基于预编码的相位纠正算法。该算法首先在用户符号中引入预先设定的相位失真矢量,然后在中继侧利用该参数对接收的PLNC信号进行相位均衡,同时修改迭代译码过程中的置... 详细信息

研究了异步物理层网络编码(PLNC)系统中的载波相位偏移问题,提出一种基于预编码的相位纠正算法。该算法首先在用户符号中引入预先设定的相位失真矢量,然后在中继侧利用该参数对接收的PLNC信号进行相位均衡,同时修改迭代译码过程中的置信传播(BP)公式,以达到缩小相位偏移的目的。建立了相位均衡收益模型,利用该模型证明了上述算法相位纠正性能的上界,并且对相位失真矢量以及算法的健壮性进行了优化。对该算法进行了验证试验,试验结果表明,该算法能有效减小相位偏移对BP译码过程的影响,改善系统的误比特性能。进行的建模与优化,为星座图不规则下的BP译码提供了一种简单有效的性能分析方法。

关键词：物理层网络编码(PLNC) 异步相位偏移置信传播(BP) 预失真

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利用似然比门限转换的自适应机会协作策略

计算机应用 2013年第10期33卷 2715-2718,2738页

作者：成聿伦杨龙祥无线通信江苏省重点实验室(南京邮电大学) 南京210003 宽带无线通信与传感网技术教育部重点实验室(南京邮电大学) 南京210003

基于解码前传的错误传播严重影响机会协作系统的选择分集增益。针对此问题,提出一种基于似然比门限转换的自适应机会协作策略:最优中继采用似然比对接收信号质量进行指示,通过与基于链路误比特率的门限值比较,动态地选择中继方式,以保... 详细信息

基于解码前传的错误传播严重影响机会协作系统的选择分集增益。针对此问题,提出一种基于似然比门限转换的自适应机会协作策略:最优中继采用似然比对接收信号质量进行指示,通过与基于链路误比特率的门限值比较,动态地选择中继方式,以保证中继链路得到充分利用。推导了平均误比特率的近似解析表达式,在此基础上对门限进行了优化。采用蒙特卡罗仿真验证了理论公式的有效性,仿真结果表明,当误比特率为0.001时,相比传统方案,该算法能节省1.2 dB的功率。

关键词：机会协作自适应似然比选择分集误比特率

Triple reverse order law for the Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Analysis of multi-objective optimisation method for main insulation structure configuration scheme of valve-side winding of ultra-high voltage converter transformer considering multi-field coupling

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High Voltage 2024年第2期9卷 296-308页

作者： Lijun Yang Zhidong cheng Li cheng Ruijin Liao State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqingChina

Because DC conductivities of oil-paper materials can be easily affected by electric field and temperature,the electrical properties under electro-thermal coupling of oil-paper materials should be considered when optimising the insulation structure of valve-side winding of the converter *** on the finite element multi-physical field coupling simulation,the multi-objective optimisation of main insulation structure of valve-side winding is carried *** view of the high time consuming of multi-physical field calculation and the actual needs of an insulation structure optimisation,the Kriging method and technique for order preference by similarity to the ideal solution(TOPSIS)method are introduced,and combines them with NSGA-II to obtain a joint algorithm that can be used for the optimisation of insulation structure of the converter *** using the joint algorithm of multi-objective optimisation,the insulation structure configuration scheme of valve-side winding is *** can be seen from the experiment result that,on the one hand,the joint algorithm adopted can obtain the insulation structure configuration scheme that meets the design *** the other hand,when facing the configuration scheme optimisation under multi-field coupling,the computational time required by this method is only 0.15%of that required by original genetic algorithm.

关键词： converter insulation coupling