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A Multi-Token Sector Antenna Neighbor Discovery Protocol for Directional Ad Hoc Networks

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China Communications 2024年第7期21卷 149-168页

作者： Zhang Hang Li Bo Yan Zhongjiang Yang Mao Li Xinru School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China The 54th research institute of cetc Shijiazhuang 050081China

In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc *** central concept of our work involves maintaining multiple tokens across the *** prevent mutual interference among multi-token holders,we introduce the time and space non-interference ***,we propose a master-slave strategy between *** the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(stHs).Using this approach,the MTH and multiple stHs can simultaneously discover their neighbors without causing interference with each *** on this foundation,we provide a comprehensive procedure for the M-SAND *** also conduct theoretical analyses on the maximum number of stHs and the lower bound of multi-token generation ***,simulation results demonstrate the time efficiency of the M-SAND *** compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed.

关键词： multi-token neighbor discovery SAND protocol sector antenna ad hoc network

A Practical Regular LDPC Coded Scheme for Physical-Layer Information Security

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China Communications 2024年第5期21卷 190-201页

作者： Du Junyi cetc Key Laboratory of Avionic Information System Southwest China Institute of Electronic TechnologyChengdu 610036China

In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from *** this end,we first propose a punctured LDPC coded scheme,where the information bits in a codeword are punctured and only the parity check bits are transmitted to the *** further propose a notion of check node type distribution and derive multi-edge type extrinsic information transfer functions to estimate the security performance,instead of the well-known weak metric bit error *** optimize the check node type distribution in terms of the signal-to-noise ratio(SNR)gap and modify the progressive edge growth algorithm to design finite-length *** results show that our proposed scheme can achieve a lower computational complexity and a smaller security gap,compared to the existing scrambling and puncturing schemes.

关键词： extrinsic information transfer function physical layer scheme secure open channel security gap

Detection of UAV Target Based on Continuous Radon Transform and Matched Filtering Process for Passive Bistatic Radar

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Journal of Beijing institute of Technology 2024年第1期33卷 9-18页

作者： Luo Zuo Yuefei Yan Jun Wang Xin Sang Yan Wang Dongming Ge Lihao Ping Zhihai Wang Congsi Wang Guangzhou institute of Technology Xidian UniversityGuangzhou 510555China National Laboratory of Radar Signal Processing Xidian UniversityXi’an710071China School of Information and Control Engineering Xi’an University of Architecture and TechnologyXi’anShaanxi 710055China cetc Wuhu Diamond Aircraft Manufacturing Co. LtdWuhuAnhui 241000China Beijing Space Vehicle General Design Department Beijing 100094China cetc No.38 research institute Hefei 230088China

Long-time integration technique is an effective way of improving target detection performance for unmanned aerial vehicle(UAV)in the passive bistatic radar(PBR),while range migration(RM)and Doppler frequency migration(DFM)may have a major effect due to the target *** paper proposed an innovative long-time coherent integration approach,regarded as Continuous Radon-matched filtering process(CRMFP),for low-observable UAV target in passive bistatic *** not only mitigates the RM by collaborative research in range and velocity dimensions but also compensates the DFM and ensures the coherent integration through the matched filtering process(MFP).Numerical and real-life data following detailed analysis verify that the proposed method can overcome the Doppler mismatch influence and acquire comparable detection performance.

关键词： passive bistatic radar unmanned aerial vehicle long-time coherent integration Radon-matched filtering process

Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate

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Defence Technology（防务技术） 2024年第2期32卷 222-231页

作者： Haotian Jian Guoqiang Zheng Lejian Chen Zheng Ning Guofu Yin Peng Zhu Ruiqi Shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing University of Science and TechnologyNanjing 210094China Anhui Province Key Laboratory of Microsystem the 43rd Research Institute of CETCHefei 230088China Science and Technology on Applied Physical and Chemistry Laboratory Shanxi Applied Physics and Chemistry Research Institute Xi'an 710061China

Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting *** solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting *** oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma *** results of the electric characteristics and the impact pressure were inconsistent with ignition *** only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating ***,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this *** HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric *** longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.

关键词： Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate

Review on the Usage of Synchronous and Asynchronous FIFOs in Digital Systems Design

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Engineering（科研） 2024年第3期16卷 61-82页

作者： Dongwei Hu Yuejun Lei Linan Wang The 54th research institute of cetc Shijiazhuang China MUC School of Information Engineering Beijing China

First-Input-First-Output (FIFO) buffers are extensively used in contemporary digital processors and System-on-Chips (SoC). There are synchronous FIFOs and asycnrhonous FIFOs. And different sized FIFOs should be implemented in different ways. FIFOs are used not only for the pipeline design within a processor, for the inter-processor communication networks, for example Network-on-Chips (NoCs), but also for the peripherals and the clock domain crossing at the whole SoC level. In this paper, we review the interface, the circuit implementation, and the various usages of FIFOs in various levels of the digital design. We can find that the usage of FIFOs could greatly facilitate the signal storage, signal decoupling, signal transfer, power domain separation and power domain crossing in digital systems. We hope that more attentions are paid to the usages of synchronous and asynchronous FIFOs and more sophististicated usages are discovered by the digital design communities.

关键词： First-Input-First-Output System-on-Chip Network-on-Chip Advanced eXtensible Interface Asynchronous

The Caching and Pricing strategy for Information-Centric Networking with Advertisers’Participation

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China Communications 2024年第3期21卷 283-295页

作者： Zheng Quan Yan Wenliang Wu Rong Tan Xiaobin Yang Jian Yuan Liu Xu Zhenghuan Laboratory for Future Networks Department of AutomationUniversity of Science and Technology of ChinaHefei 230026China institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China Suzhou Nuclear Power research institute Suzhou 215004China National Engineering Laboratory for Public Safety Risk Perception and Control by Big Data(NEL-PSRPC) China Academy of Electronics and Information Technology of CETCBeijing 100041China

As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’***,the Information-Centric Networking(ICN)came into *** a technical point of view,ICN is a promising future network *** and customizing a reasonable pricing mechanism plays a positive role in promoting the deployment of *** current research on ICN pricing mechanism is focused on paid ***,we study an ICN pricing model for free content,which uses game theory based on Nash equilibrium to *** this work,advertisers are considered,and an advertiser model is established to describe the economic interaction between advertisers and ICN *** solution can formulate the best pricing strategy for all ICN entities and maximize the benefits of each *** extensive analysis and numerical results show that the proposed pricing framework is significantly better than existing solutions when it comes to free content.

关键词： advertisers cache free content Information-Centric Networking pricing strategy

Channel Correlation Based User Grouping Algorithm for Nonlinear Precoding Satellite Communication System

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China Communications 2024年第1期21卷 200-214页

作者： Ke Wang Baorui Feng Jingui Zhao Wenliang Lin Zhongliang Deng Dongdong Wang Yi Cen Genan Wu School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information Engineering Minzu University of ChinaBeijing 100081China institute of Spacecraft Application System Engineering China Academy of Space TechnologyBeijing 100094China Academy for Network and Communications of cetc Science and Technology on Communication Networks LaboratoryShijiazhuang 050081China

Low Earth Orbit(LEO)multibeam satellites will be widely used in the next generation of satellite communication systems,whose inter-beam interference will inevitably limit the performance of the whole *** precoding such as Tomlinson-Harashima precoding(THP)algorithm has been proved to be a promising technology to solve this problem,which has smaller noise amplification effect compared with linear ***,the similarity of different user channels(defined as channel correlation)will degrade the performance of THP *** this paper,we qualitatively analyze the inter-beam interference in the whole process of LEO satellite over a specific coverage area,and the impact of channel correlation on Signal-to-Noise Ratio(SNR)of receivers when THP is *** user grouping algorithm is proposed based on the analysis of channel correlation,which could decrease the number of users with high channel correlation in each precoding group,thus improve the performance of ***,our algorithm is designed under the premise of co-frequency deployment and orthogonal frequency division multiplexing(OFDM),which leads to more users under severe inter-beam interference compared to the existing research on geostationary orbit satellites broadcasting *** results show that the proposed user grouping algorithm possesses higher channel capacity and better bit error rate(BER)performance in high SNR conditions relative to existing works.

关键词： channel correlation inter-beam interference multibeam satellite Tomlinson-Harashima precoding user grouping

Scalability and Security in Identifier-to-Locator Mapping: Case study for Locator/ID Separated Networks

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China Communications 2011年第7期8卷 34-45页

作者：吴恒奎杨冬高德云张宏科 The Science and Technology on Electronic Test & Measurement Laboratory 41st Research Institute of CETC School of Electronics and Information Engineering Beijing Jiaotong University

The locator/ID separation paradigm has been widely discussed to resolve the serious scalability issue that today's Internet is facing. Many researches have been carried on with this issue to alleviate the routing burden of the Default Free Zone (DFZ), improve the traffic engineering capabilities and support efficient mobility and multi-homing. However, in the locator/ID split networks, a third party is needed to store the identifier-to-locator pairs. How to map identifiers onto locators in a scalable and secure way is a really critical challenge. In this paper, we propose SS-MAP, a scalable and secure locator/ID mapping scheme for future Internet. First, SS-MAP uses a near-optimal DHT to map identifiers onto locators, which is able to achieve the maximal performance of the system with reasonable maintenance overhead relatively. Second, SS-MAP uses a decentralized admission control system to protect the DHT-based identifier-to-locator mapping from Sybil attacks, where a malicious mapping server creates numerous fake identities (called Sybil identifiers) to control a large fraction of the mapping system. This is the first work to discuss the Sybil attack problem in identifier-to-locator mapping mechanisms with the best knowledge of the authors. We evaluate the performance of the proposed approach in terms of scalability and security. The analysis and simulation results show that the scheme is scalable for large size networks and can resistant to Sybil attacks.

关键词： Locator/ID separation identifier-to-locator mapping scalability security Sybil attack

Axial Micro-strain Sensor Based on Resonance Demodulation Technology Via Dual-Mode CMECF

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Photonic Sensors 2019年第1期9卷 78-88页

作者： Xiao LIANG Tigang NING Jingcong LI Yang LI Zhiming LIU College of Science Minzu University of ChinaBeijing 100081China institute of Lightwave Technology Beijing Jiaotong UniversityBeijing 100044China The 41st research institute of cetc Qingdao 266555China

This paper firstly and experimentally demonstrates an in-fiber axial micro-strain sensing head,combined with a Mach-Zehnder interferometer(MZI)based on the concentric multilayer elliptical-core fiber(CMECF).This MZI with a high extinction ratio(about 15dB)is successfully achieved with a CMECF-single mode fiber-CMECF(CSC)*** MZI sensor theory and the resonance demodulation technology are systematically described in this *** this CSC structure, two sections of the CMECF have a role as the mode generator and coupler,***01 and LPlleven,which have similar excitation coefficients,are two dominated propagating mode groups supported in the *** account of the distinct dual-mode property,a good stability of this sensor is *** detected resonance in the MZI shifts as the axial micro-strain variated due to the strong interaction between higher order *** sensitivity of^1.78pm/με is experimentally achieved within the range of 0με-1250με,meanwhile,the intensity fluctuation is below 0.38dB.

关键词： Few-mode fiber fiber sensor MZI axial micro-strain