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INTELLIGENT information NETWORK SECURITY AND MANAGEMENT

China communications 2016年第7期13卷 3-6页

作者： Yixian Yang Zhongshan Zhang Wenjing Li Information Security Center(ISC) Beijing University of Posts and Telecommunications(BUPT) National Engineering Laboratory for Disaster Backup and Recovery the School of Computer and Communication Engineering in the University of Science and Technology Beijing(USTB) State Key Lab of Networking and Switching Technologies Network Management Research Center at BUPT National Innovation Research Group of China

Intelligent information Network Security and Management(IINSM)is an emerging direction in future Internet architecture research,which has gained significant tractions among academia and *** the rapid development of modern society,intelligent information network with the computer as the core technology is widely used in every aspect of social ***

关键词： DCT INTELLIGENT information NETWORK SECURITY AND MANAGEMENT Simulation DWT DCNN

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Realization of a new random access scheme for resource efficiency in M2M communications

Realization of a new random access scheme for resource effic...

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International Symposium on Wireless Personal Multimedia communications (WPMC)

作者： Xia Zhu Ningbo Zhang Guixia Kang Yifan Zhang Shuang Zhang Science and Technology on Information Transmission and Dissemination in Communication Networks Lab China Key Laboratory of Universal Wireless Communications (BUPT) Ministry of Education China

ISBN: (纸本)9781509053773

To raise the resource efficiency in Machine-to-Machine (M2M) communication, we realize a new random access (RA) procedure. In the improved RA scheme, we use Code Division Multiple Access (CDMA) to transmit User Equipment Identity (UE ID) and Cyclic Redundancy Check(CRC) information in the first step of RA procedure, and then distinguish each UE and detect preamble collisions in the second step. We then analyse RB allocation between Physical Uplink Shared Channel (PUSCH) and Physical Random Access Channel (PRACH) accordingly. Results show that the new scheme has a good performance and can save resource up to 40%.

关键词： Machine-to-machine communications Schedules Signal to noise ratio Wireless communication Multiaccess communication Multimedia communication Resource management

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Matched Filter Based Spectrum Sensing When Primary User Has Multiple Power Levels

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China communications 2015年第2期12卷 21-31页

作者： ZHANG Xinzhi GAO Feifei CHAI Rong JIANG Tao Key Lab of Mobile Communication Technology Chongqing University of Posts and Telecommunications Department of Automation Tsinghua UniversityState Key Lab of Intelligent Technologies and SystemsTsinghua National Laboratory for Information Science and Technology(TNList) Beijing Wuhan National Laboratory for Optoelectronics Department of Electronic and InformationHuazhong University of Science and Technology

In this paper,we investigate the matched filter based spectrum sensing in a more reasonable cognitive radio(CR) scenario when the primary user(PU) has more than one transmit power levels,as regulated in most standards,i.e.,IEEE 802.11 Series,GSM,LTE,LTE-A,*** new multiple primary transmit power(MPTP) scenario is specialized by two different targets:detecting the presence of PU and identifying the power *** to the traditional binary sensing where only the presence of PU is checked,SU may attain more information about the primary network(making CR more "intelligent") and design the subsequent optimization *** key technology is the multiple hypothesis testing as opposed to the traditional binary hypothesis *** discuss two situations under whether the channel phase is known or not,and we derive the closed form solutions for decision regions and several performance metrics,from which some interesting phenomenons are observed and the related discussions are *** examples are provided to corroborate the proposed studies.

关键词： spectrum sensing power recognition matched filter multiple primary transmit power multiple hypothesis testing power mask

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An allocation scheme between random access and DAMA channels for satellite networks

An allocation scheme between random access and DAMA channels...

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International Conference on communication Systems

作者： Ruijun Chang Yizhou He Gaofeng Cui Weidong Wang Information & Electronics Technology Lab School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing Science and Technology on Information Transmission and Dissemination in Communication Network Laboratory Shijiazhuang Ministry of Education Key Laboratory of Universal Wireless Communications Beijing China Academy of Information and Communications Technology Beijing

ISBN: (纸本)9781509034246

Although great progress on satellite multiple access has been made both in Random Access (RA) algorithms and Demand Assigned Multiple Access (DAMA), packets collision in RA strategy and large latency in DAMA still present an obstacle to the applying for complex dynamic network respectively. This paper proposes a combination scheme of the two strategies. By taking advantages of both, the scheme assigns all the channels of the system with the two access approaches. An allocation algorithm between RA and DA channels is presented and the simulation results show that a significant improvement on system throughput has been achieved and the average delay is controlled within a considerable level efficiently.

关键词： Delays Throughput Resource management Satellites Protocols Channel allocation Downlink

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Carrier frequency offset estimation scheme for quasi-constant envelope OFDM satellite system under AWGN channel

Carrier frequency offset estimation scheme for quasi-constan...

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International Conference on Wireless communications and Signal Processing (WCSP)

作者： Cheng Wang Yizhou He Weiwei Xu Gaofeng Cui Weidong Wang Information & Electronics Technology Lab School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing The Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Shijiazhuang Ministry of Education Key Laboratory of Universal Wireless Communications Beijing China Academy of Information and Communications Technology Beijing

ISBN: (纸本)9781509028610

Quasi-Constant Envelope OFDM transmits dual-stream simultaneously to improve the spectral efficiency of Constant Envelope OFDM. It can provide high data rate links and maintain a low PAPR to reduce the distortion caused by the nonlinear power amplifier. Thus, the quasi-constant envelope OFDM is suitable for satellite communication system. However, the carrier frequency offset (CFO) in satellite communication must be estimated and compensated before the demodulation. In this paper a CFO estimation scheme is proposed for quasi-constant envelope OFDM satellite system under additive white Gaussian noise (AWGN) channel. Since the null subcarrier at the transmitter can be considered as the prior information at the receiver, this null subcarrier can be used to estimate the CFO through phase demodulator and inverse discrete Fourier transform (IDFT) module at the receiver. Mathematical analysis reveals that the ideal estimation range of normalized CFO is nearly half of the size of IDFT under AWGN channel. Simulation results show that the proposed scheme performs well at moderate and high signal-to-noise ratio (SNR) conditions.

关键词： Estimation Peak to average power ratio Satellite communication AWGN channels Satellites Demodulation

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Doppler rate estimation scheme for UFMC based LEO satellite communication system

Doppler rate estimation scheme for UFMC based LEO satellite ...

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International Conference on communication Systems

作者： Mingjun Xu Yizhou He Cheng Wang Gaofeng Cui Weidong Wang Information & Electronics Technology Lab School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing The Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Shijiazhuang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing China Academy of Information and Communications Technology Beijing

ISBN: (纸本)9781509034246

As communication quality and stability are seriously impacted by high Doppler rate in low earth orbit (LEO) satellite communication system, it is quite important and imperative to compensate high Doppler rate precisely. Due to the frequency shift insensitivity feature of Zadoff-Chu (ZC) sequence, this paper presents a Doppler rate estimation algorithm based on ZC sequence in LEO universal-filtered multi-carrier (UFMC) system. According to the principle of second order difference (SOD), Doppler rate can be estimated by calculating conjugate multiplication three times between received signal and native ZC sequence. This algorithm is first used in UFMC system and don't need the Doppler shift pre-estimation. In the scenario of LEO satellite, the simulation results show that the normalized Doppler rate estimation range of this algorithm is limited within (-0.5, 0.5). If the absolute value of normalized Doppler rate is less than 0.4, mean square error (MSE) performance of Doppler rate is good and acceptable. The proposed algorithm is suitable for LEO satellite communication system.

关键词： Estimation Low earth orbit satellites Doppler shift OFDM Time-domain analysis

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Deterministic realization of collective measurements via photonic quantum walks

arXiv

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arXiv 2017年

作者： Hou, Zhibo Tang, Jun-Feng Shang, Jiangwei Zhu, Huangjun Li, Jian Yuan, Yuan Wu, Kang-Da Xiang, Guo-Yong Li, Chuan-Feng Guo, Guang-Can Key Laboratory of Quantum Information University of Science and Technology of China CAS Hefei230026 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei230026 China Naturwissenschaftlich-Technische Fakultät Universität Siegen Siegen57068 Germany Beijing Key Laboratory of Nanophotonics Ultrafine Optoelectronic Systems School of Physics Beijing Institute of Technology Beijing100081 China Institute for Theoretical Physics University of Cologne Cologne50937 Germany Department of Physics Center for Field Theory and Particle Physics Fudan University Shanghai200433 China Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai200433 China State Key Laboratory of Surface Physics Fudan University Shanghai200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing210093 China Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China

Collective measurements on identically prepared quantum systems can extract more information than local measurements, thereby enhancing information-processing efficiency. Although this nonclassical phenomenon has been known for two decades, it has remained a challenging task to demonstrate the advantage of collective measurements in experiments. Here we introduce a general recipe for performing deterministic collective measurements on two identically prepared qubits based on quantum walks. Using photonic quantum walks, we realize experimentally an optimized collective measurement with fidelity 0.9946 without post selection. As an application, we achieve the highest tomographic efficiency in qubit state tomography to date. Our work offers an effective recipe for beating the precision limit of local measurements in quantum state tomography and metrology. In addition, our study opens an avenue for harvesting the power of collective measurements in quantum information processing and for exploring the intriguing physics behind this power. Copyright © 2017, The Authors. All rights reserved.

关键词： Quantum optics

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A simple frequency-domain equalizer over doubly-selective channel without feedback

A simple frequency-domain equalizer over doubly-selective ch...

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International Conference on Computer, information and Telecommunication Systems (CITS)

作者： Zhuo Ma WanWan Gao Shuanyi Du Bo Kang Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Xi'an China The State Key Lab. of ISN Xidian University TBEA Xi'an Electric Technology Co Ltd

ISBN: (纸本)9781509006915

Frequency-domain equalization (FDE) is prior than time-domain equalization in complexity. FDE is based on the cyclic signal property within a data block. This means that the channel must remain constant during this time interval. But in fast fading environments, the channel is time-variant. In order to deal with this problem, a variety of sub-block based FDE techniques have been proposed, but these kinds of algorithms have very high complexity because a tentative equalization and decoding are necessary before sub-block processed. In many practical applications requiring high real-time attribution, processing speed of algorithms is more important than processing capacity, so we must sacrifice performance of algorithm in exchange for speed at this time. In this paper, a simple FDE algorithm without tentative equalization and decoding is proposed for fast fading channel. The proposed method reduces the complexity of algorithm by preserving partial of the frequency equalization result instead of tentative equalizing and decoding. Numerical simulation results show that this lower complexity of algorithm can also effectively decrease the intersymbol interference(ISI) in fast fading environment.

关键词： Time-domain analysis Complexity theory Frequency-domain analysis Fading channels Decoding OFDM Channel estimation

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Delaunay triangulation and mesh grid combining algorithm for multiple targets localization using compressive sensing

Delaunay triangulation and mesh grid combining algorithm for...

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International Symposium on Wireless Personal Multimedia communications (WPMC)

作者： Xiaofei Lin Kangyong You Wenbin Guo Wireless Signal Processing and Network Lab Beijing University of Posts & Telecommunications Beijing China Science and Technology on Information Transmission Dissemination in Communication Networks Laboratory Shijiazhuang China

ISBN: (纸本)9781509053773

Introducing compressive sensing theory to solve multiple targets localization problem is a promising method by only considering received signal's power. In previous researches, the targets are assumed to be positioned into an regular mesh grid and restoration model according to compressive underdetermined equation is built to recover the positions of unknown targets. However, it is inconvenient to arrange sensors on grids in practice and the recovered locations were bound to grid points that may deviate the target positions comparing to the real ones. In this paper, we propose a Delaunay triangulation grid generation algorithm through randomly deployed sensors' positions. Moreover, a sparse position vector diversity combining algorithm, based on OMP, is also been proposed. It lowers the possibility of the emergence of the false locations and greatly improves the accuracy of targets' positions.

关键词： Sensors Diversity reception Topology Wireless sensor networks Position measurement Compressed sensing Wireless communication

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Optical Modulation: Few-Layer Phosphorene-Decorated Microfiber for All-Optical Thresholding and Optical Modulation (Advanced Optical Materials 9/2017)

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Advanced Optical Materials 2017年第9期5卷

作者： Jilin Zheng Xian Tang Zhenghua Yang Zhiming Liang Yunxiang Chen Ke Wang Yufeng Song Ying Zhang Jianhua Ji Yong Liu Dianyuan Fan Han Zhang Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University Shenzhen 518060 China Institute of Communication Engineering PLA University of Science and Technology Nanjing 210007 China College of Information Engineering and Shenzhen Key Lab of Communication and Information Processing Shenzhen University Shenzhen 518060 China State Key Laboratory on Electronic Thin Film and Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

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