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Synchronization for the Environment of OFDM Cooperative Communications Based on Preamble Design and Phase Rotation

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China Communications 2015年第9期12卷 122-132页

作者： Wang Xue qian zhihong Fu Yu College of Communication Engineering Jilin University

Timing and carrier frequency offset estimation are critical issue for OFDM cooperative communications. In view of the complexity and high accuracy requirement, 1/2 and 1/4 pilot symbol cycle CAZAC sequence structures are defined as the pilot frequency sequence. Estimation within one symbol cycle is carried out through averaging samples of two neighboring symbol cycles, after which the operation is expanded to all the symbol cycles in one band group. Taking multipath effect into account, the concept of phase rotation is proposed for a further step. Adjust the phase difference of estimated symbols by phase rotation, and cross estimation could be done. Meanwhile, timing scheme works within one cycle training sequence. Theoretical and simulation analysis indicate that CRLB does not only relate to estimation symbol length, but also be influenced by phase difference of estimation symbols seriously. In the condition that the length of estimation is fixed, the bigger the phase rotation angle is, the smaller the CRLB is. The complexity of proposed algorithm is less than full cycle average estimation method for almost 50%. Meanwhile, the estimation accuracy is approximate with the full cycle average estimation method as well. Timing scheme with the defined preamble structure is also proposed. Simulation proves its efficiency.

关键词： OFDM frequency offset estimation preamble phase rotation

Identifying the Unknown Tags in a Large RFID System

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China Communications 2017年第1期14卷 135-145页

作者： Yu Fu zhihong qian Xue Wang Guiqi Liu College of Communication Engineering Jilin University Changchun 130012 China

Radio frequency identification(RFID) technology has been extensively used in various practical applications, such as inventory management and logistics control, with its outstanding features(e.g. non-line-ofsight reading and fast identification). And in a large RFID system, unknown tag identification uses total execution time as the performance criterion. However, the performance of existing protocols in terms of execution time is not ideal. To get better time efficiency, a novel unknown tag identification protocol(NUTIP) is proposed. The novelty of NUTIP is demonstrated mainly in two aspects: i) NUTIP deactivates some known tags and identifies or labels some unknown tags during its first phase to prevent these tags from interfering unknown tag identification. ii) We optimize the parameter settings to minimize the total execution time. Simulation experiments show that the proposed protocol is far superior to other relevant protocols and suitable for both sparse unknown tags environment and dense unknown tags environment.

关键词： radio frequency identification unknown tag identification time-efficient identification accuracy

An Overview of Anti-Collision Protocols for Radio Frequency Identification Devices

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China Communications 2014年第11期11卷 44-59页

作者： qian zhihong WANG Xue College of Communication Engineering Jilin University Changchun Jilin China 130012

Radio frequency identification(RFID) is a new type of non-contact automatic identification *** to its low energy consumption,low cost,and its adaptability to harsh environments,it has been applied to many *** the RFID systems,data collision is inevitable when the reader sends a communication request and multiple tags respond with simultaneous data *** collision is prone to causing problems such as:identification delay,spectrum resource waste,a decreased system throughput rate,***,an efficient,stable anti-collision protocol is crucial for RFID *** research analysed the current research into RFID anticollision protocols and summarised means for its improvement through the mechanism of implementation of different types anticollision ***,a new direction is proposed for the future development of RFID anti-collision protocol systems.

关键词： radio frequency identification automatic identification data collision anticollision protocol.

An Adaptive Tag Anti-Collision Protocol in RFID Wireless Systems

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China Communications 2014年第7期11卷 117-127页

作者： LIU Xiaohui qian zhihong ZHAO Yanhang GUO Yuqi College of Communication Engineering Jilin University Changchun 130012China

A novel anti-collision algorithm in RFID wireless network is *** it is put forward on the basis of collision tree(CT)and improved collision tree(lCT) anti-collision protocols,we call it adaptive collision tree protocol(ACT).The main novelty of this paper is that the AD strategy is introduced and used in ACT to decrease collisions and improve the tag system *** strategy means that query strings will divide into two or four branches adaptively according to the label *** scheme can decrease both depth of query and collision timeslots,and avoid producing too much idle timeslots at the same *** theoretical analysis and simulation results indicate that the novel proposed anticollision protocol ACT outperforms the previous CT and ICT protocols in term of time complexity,system throughput,and communication complexity.

关键词： RFID anti-collision collisiontree(CT) improved collision tree(ICT) ADstrategy.

Diffuse midline glioma treated with epigenetic agent-based immunotherapy

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Signal Transduction and Targeted Therapy 2023年第2期8卷 365-368页

作者： Linkai Jing zhihong qian qiang Gao Rui Sun Zili Zhen Guihuai Wang Xuejun Yang Haitao Li Tiannan Guo Wei Zhang Department of Neurosurgery Beijing Tsinghua Changgung HospitalTsinghua UniversityBeijingPeople’s Republic of China Department of Basic Medical Sciences School of MedicineTsinghua UniversityBeijingPeople’s Republic of China School of Clinical Medicine Tsinghua UniversityBeijingPeople’s Republic of China Key Laboratory of Structural Biology of Zhejiang Province School of Life SciencesWestlake UniversityZhejiangPeople’s Republic of China Institute of Basic Medical Sciences Westlake Institute for Advanced StudyZhejiangPeople’s Republic of China Ministry of Education Key Laboratory of Protein Sciences Beijing Advanced Innovation Center for Structural BiologyBeijing Frontier Research Center for Biological StructureDepartment of Basic Medical SciencesSchool of MedicineTsinghua UniversityBeijingPeople’s Republic of China Tsinghua-Peking Center for Life Sciences Tsinghua UniversityBeijingPeople’s Republic of China IDG/McGovern Institute for Brain Research School of Life SciencesTsinghua UniversityBeijingPeople’s Republic of China

Dear Editor,Diffuse midline glioma,H3K27-altered(DMG),is a pediatric-type high-grade diffuse glioma that preferentially localizes to the brainstem or pons,thalamus,and spinal *** resection is challenging and biopsy is often performed in most *** date,no conventional,targeted or immune therapy has been convincingly shown to improve patients’overall survival(OS).

关键词： glioma immunotherapy brainstem

维普期刊数据库评论

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用噪声测量方法分析模拟电路故障的研究

仪器仪表学报 2005年第6期26卷 650-652,657页

作者：钱志鸿张琳吉林大学通信工程学院长春130025 佳木斯大学信息电子技术学院佳木斯154007

提出了一种用噪声测量及分析理论进行模拟电路诊断的方法,即一种因-果逆向推理方法。与传统的因-果推理方法比较,这种方法无需对故障的类型及是否存在作预先限定,且能对复合性故障进行分析诊断。鉴于模拟电路故障的诊断比器件缺陷的检... 详细信息

提出了一种用噪声测量及分析理论进行模拟电路诊断的方法,即一种因-果逆向推理方法。与传统的因-果推理方法比较,这种方法无需对故障的类型及是否存在作预先限定,且能对复合性故障进行分析诊断。鉴于模拟电路故障的诊断比器件缺陷的检测难度更大,这里论证了模拟电路输出噪声的计算方法,分析了电路故障情况与正常情况时的差别,讨论了电路故障诊断的方法。最后,利用这种方法对一种有源滤波器的电路故障进行了诊断和分析。

关键词：模拟电路故障诊断噪声测量

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面向未来移动网络密集连接的关键技术综述

通信学报 2021年第4期42卷 22-43页

作者：钱志鸿肖琳王雪吉林大学通信工程学院吉林长春130012

在总结密集连接相关研究的基础上,阐述了未来移动通信网络中密集终端接入的关键技术,分析了网络架构及相关技术、密集连接的传输技术和接入技术等几个重点方向的研究进展,提出了多种连接形式并存的灵活性网络结构。针对上下行覆盖不对... 详细信息

在总结密集连接相关研究的基础上,阐述了未来移动通信网络中密集终端接入的关键技术,分析了网络架构及相关技术、密集连接的传输技术和接入技术等几个重点方向的研究进展,提出了多种连接形式并存的灵活性网络结构。针对上下行覆盖不对称问题,结合用户的服务质量需求,提出了基于上下行分离网络架构的密集终端接入方案,阐述了为应对大规模组网和密集连接需求要实现的网络架构立体化和通信与计算一体化的必要性,并基于太赫兹和区块链等技术对频段向上延伸和频谱资源共享等未来重点研究方向进行了讨论与展望。

关键词：密集连接移动网络网络架构接入技术通信与计算一体化

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自适应高效无线传感器网络时间同步优化算法

电子与信息学报 2022年第8期44卷 2802-2813页

作者：王义君钱志鸿长春理工大学电子信息工程学院长春130022 吉林大学通信工程学院长春130012

针对无线传感器网络全网多跳自适应时间同步效率低的问题,在接收端与接收端同步模型基础上,该文提出一种自适应高效无线传感器网络时间同步优化算法(AEO)。首先,双节点同步时,从节点接收来自参考节点的同步消息并进行确认,在同步周期结... 详细信息

针对无线传感器网络全网多跳自适应时间同步效率低的问题,在接收端与接收端同步模型基础上,该文提出一种自适应高效无线传感器网络时间同步优化算法(AEO)。首先,双节点同步时,从节点接收来自参考节点的同步消息并进行确认,在同步周期结束后通过拟合估计和数据更新完成时间修正,构建交互参数同步包,并与主节点进行信息交换完成同步过程。其次,全网同步时,建立Voronoi多边形拓扑结构,认定拓扑结构中参考节点和邻域节点身份(ID),参考节点覆盖区域间通过邻域节点交换同步信息,实现自适应多区域节点联合时间同步。仿真结果表明该算法在双节点时间同步中能够保证同步误差较小,网络能耗较低;同时,Voronoi拓扑相较于其他典型拓扑,在连通效率和收敛时间方面均有所改进。

关键词：无线传感器网络时间同步接收端同步 Voronoi图

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室内环境中基于天牛须寻优的普适定位方法

电子与信息学报 2019年第7期41卷 1565-1571页

作者：刘影钱志鸿贾迪辽宁工程技术大学电子与信息工程学院葫芦岛125105 吉林大学通信工程学院长春130022

在复杂的室内环境中,测得的接收信号强度(RSS)值会出现不同程度的波动,导致无法准确地刻画出无线信号传播模型。为了解决这个问题,在基于Wi-Fi测距定位模型下,该文提出一种普适的粗粒度定位方法。该方法通过对测量到的RSS值进行拟合,以... 详细信息

在复杂的室内环境中,测得的接收信号强度(RSS)值会出现不同程度的波动,导致无法准确地刻画出无线信号传播模型。为了解决这个问题,在基于Wi-Fi测距定位模型下,该文提出一种普适的粗粒度定位方法。该方法通过对测量到的RSS值进行拟合,以此获取信号的传播模型;在此基础上计算出未知节点与接入点(AP)的距离,再利用天牛须算法实现未知节点定位,通过仿真验证此传播模型的性能以及该优化算法的有效性。

关键词：无线通信信道模型天牛须搜索普适定位