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Fast measurement and prediction method for electromagnetic susceptibility of receiver

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Journal of systems Engineering and electronics 2024年第2期35卷 275-285页

作者： CHEN Yan LU Zhonghao LIU Yunxia state key laboratory of complex electromagnetic environment effects on electronics and information system College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China state key laboratory of Astronautic Dynamics Xi’an 710043China

Aiming at evaluating and predicting rapidly and accurately a high sensitivity receiver’s adaptability in complex electromagnetic environments,a novel testing and prediction method based on dual-channel multi-frequency is proposed to improve the traditional two-tone test.Firstly,two signal generators are used to generate signals at the radio frequency(RF)by frequency scanning,and then a rapid measurement at the intermediate frequency(IF)output port is carried out to obtain a huge amount of sample data for the subsequent analysis.Secondly,the IF output response data are modeled and analyzed to construct the linear and nonlinear response constraint equations in the frequency domain and prediction models in the power domain,which provide the theoretical criteria for interpreting and predicting electromagnetic susceptibility(EMS)of the receiver.An experiment performed on a radar receiver confirms the reliability of the method proposed in this paper.It shows that the interference of each harmonic frequency and each order to the receiver can be identified and predicted with the sensitivity model.Based on this,fast and comprehensive evaluation and prediction of the receiver’s EMS in complex environment can be efficiently realized.

关键词： electromagnetic susceptibility(EMS) receiver dualchannel multi-frequency nonlinear response frequency domain power domain

Outage Analysis of Optimal UAV Cooperation with IRS via Energy Harvesting Enhancement Assisted Computational Offloading

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1885-1905页

作者： Baofeng Ji Ying Wang Weixing Wang Shahid Mumtaz Charalampos Tsimenidis School of information Engineering Henan University of Science and TechnologyLuoyang471000China Research and Innovation Center of Intelligent system Longmen LaboratoryLuoyang471000China state key laboratory of complex electromagnetic environment effects on electronics and information system(cemeE) Luoyang471000China Sustainable Digital Communications and Energy systems(DIGCOM)Group Nottingham Trent UniversityNottinghamUK

The utilization of mobile edge computing(MEC)for unmanned aerial vehicle(UAV)communication presents a viable solution for achieving high reliability and low latency communication.This study explores the potential of employing intelligent reflective surfaces(IRS)andUAVs as relay nodes to efficiently offload user computing tasks to theMEC server system model.Specifically,the user node accesses the primary user spectrum,while adhering to the constraint of satisfying the primary user peak interference power.Furthermore,the UAV acquires energy without interrupting the primary user’s regular communication by employing two energy harvesting schemes,namely time switching(TS)and power splitting(PS).The selection of the optimal UAV is based on the maximization of the instantaneous signal-to-noise ratio.Subsequently,the analytical expression for the outage probability of the system in Rayleigh channels is derived and analyzed.The study investigates the impact of various system parameters,including the number of UAVs,peak interference power,TS,and PS factors,on the system’s outage performance through simulation.The proposed system is also compared to two conventional benchmark schemes:the optimal UAV link transmission and the IRS link transmission.The simulation results validate the theoretical derivation and demonstrate the superiority of the proposed scheme over the benchmark schemes.

关键词： Unmanned aerial vehicle(UAV) intelligent reflective surface(IRS) energy harvesting computational offloading outage probability

Time-resolved characteristics of a nanosecond pulsed multi-hollow needle plate packed bed dielectric barrier discharge

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Plasma Science and Technology 2024年第7期26卷 48-57页

作者：秦亮李瑶郭浩姜楠宋颖贾锐周雄峰袁皓杨德正 key laboratory of Materials Modification by Laser Ionand Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024People’s Republic of China School of Electrical Engineering Dalian University of TechnologyDalian 116024People’s Republic of China state key laboratory of complex electromagnetic environment effects on electronics and information system Luoyang 471003People’s Republic of China School of Physics and Materials Engineering Dalian Minzu UniversityDalian 116600People’s Republic of China

In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and achieve large-volume stable discharge.The dynamic characteristics of the plasma,the generated active species,and the energy transfer mechanisms in both positive discharge(PD)and negative discharge(ND)are investigated by using fast-exposure intensified charge coupled device(ICCD)images and time-resolved optical emission spectra.The experimental results show that the discharge intensity,number of discharge channels,and discharge volume are obviously enhanced when the multi-needle electrode is replaced by a multihollow needle electrode.During a single voltage pulse period,PD mainly develops in a streamer mode,which results in a stronger discharge current,luminous intensity,and E/N compared with the diffuse mode observed in ND.In PD,as the gap between dielectric beads changes from 0 to250μm,the discharge between the dielectric bead gap changes from a partial discharge to a standing filamentary micro-discharge,which allows the plasma to leave the local area and is conducive to the propagation of surface streamers.In ND,the discharge only appears as a diffusionlike mode between the gap of dielectric beads,regardless of whether there is a discharge gap.Moreover,the generation of excited states N_(2)^(+)(B^(2)∑_(u)^(+))and N2(C^(3)Π_(u))is mainly observed in PD,which is attributed to the higher E/N in PD than that in ND.However,the generation of the OH(A^(2)∑^(+))radical in ND is higher than in PD.It is not directly dominated by E/N,but mainly by the resonant energy transfer process between metastable N_(2)(A^(3)∑_(u)^(+))and OH(X^(2)Π).Furthermore,both PD and ND demonstrate obvious energy relaxation processes of electron-to-vibration and vibration-to-vibration,and no vibration-to-rotation energy relaxation process is observed.

关键词： packed bed reactor multi-hollow needle electrodes positive and negative discharges optical emission spectra time-resolved images

Anti-Jamming Null Space Projection Beamforming Based on Symbiotic Radio

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工程与科学中的计算机建模(英文) 2024年第1期138卷 679-689页

作者： Baofeng Ji Yifan Liu Tingpeng Li Ling Xing Weixing Wang Shahid Mumtaz Xiaolong Shang Wanying Liu Congzheng Han state key laboratory of complex electromagnetic environment effects on electronics and information system(cemeE) Luoyang471000China Research and Innovation Center of Intelligent system Longmen LaboratoryLuoyang471000China College of information Engineering Henan University of Science and TechnologyLuoyang471000China Institute of Atmospheric Physics Chinese Academy of Sciences(LAGEO)Beijing100000China Instituto de Telecomunicaes Aveiro3800-005Portugal Chinese Academy of Agricultural Mechanization Sciences Beijing100000China

With the development of information technology,more and more devices are connected to the Internet through wireless communication to complete data interconnection.Due to the broadcast characteristics ofwireless channels,wireless networks have suffered more and more malicious attacks.Physical layer security has received extensive attention from industry and academia.MIMO is considered to be one of the most important technologies related to physical layer security.Through beamforming technology,messages can be transmitted to legitimate users in an offset direction that is as orthogonal as possible to the interference channel to ensure the reception SINR by legitimate users.Combining the symbiotic radio(SR)technology,this paper considers a symbiotic radio antijamming MIMO system equipped with a multi-antenna system at the main base station.In order to avoid the interference signal and improve the SINR of the signal received by the user.The base station is equipped with a uniform rectangular antenna array,and using Null Space Projection(NSP)Beamforming,Intelligent Reflecting Surface(IRS)can assist in changing the beam’s angle.The simulation results show that NSP Beamforming could make a better use of the null space of interference,which can effectively improve the received SINR of users under directional interference,and improve the utilization efficiency of signal energy.

关键词： Symbiotic radio anti-jamming MIMO NSP Beamforming physical layer security

Performance Study of MIMO-OSTBC Parallel Relay FSO system Based on GFDM

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Chinese Journal of electronics 2024年第2期33卷 564-572页

作者： Rui ZHOU Yong WANG Yi WANG key laboratory of electromagnetic Wave information Technology and Metrology of Zhejiang Province College of Information Engineering China Jiliang University state key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

This paper investigates the performance of a new generalized frequency division multiplexing(GFDM)parallel relay free space optical(FSO) communication system using multi-input multi-output(MIMO) orthogonal space-time block codes(OSTBC) scheme. Under the M distribution atmospheric turbulence, taking into account the triple effects of irradiance, pointing errors and path loss, the mathematical expression of system symbol error rate is derived with the help of Meijer G-function. The symbol error performance of GFDM is compared with on-off keying,Gaussian minimum shift keying, polarization shift keying and orthogonal frequency division multiplexing(OFDM)modulation methods. The effects of the MIMO-OSTBC parallel relay scheme on the GFDM system including filter roll down coefficient, the number of transmitting and receiving antennas, the number of relays, normalized beamwidth and jitter variance are analyzed, and the numerical results are verified by Monte Carlo simulation. This work provides a good foundation for engineering applications.

关键词： Free-space optical Generalized frequency division multiplexing Multi-input multi-output Orthogonal space-time block codes Parallel relay

Source enumeration method by combining diagonal loading and constructing second-order statistics

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中国邮电高校学报：英文版 2023年第1期30卷 47-55页

作者： Wang Chuanchuan Zeng Yonghu Wang Liandong Li Zhipeng state key laboratory of complex electromagnetic environment effects on electronics and information system Luoyang 471003China

A source enumeration method based on diagonal loading of eigenvalues and constructing second-order statistics is proposed,for the case that the antenna array observed signals are overlapped with spatial colored noise,and the number of antennas compared with the number of snapshots meet the requirement of general asymptotic regime.Firstly,the sample covariance matrix of the observed signals is obtained,the eigenvalues of the sample covariance matrix can be acquired by eigenvalue decomposition,and the eigenvalues are diagonally loaded,and a new formula for calculating the diagonal loading is presented.Based on the diagonal loaded eigenvalues,the difference values are calculated for the adjacent eigenvalues after diagonal loading,and the statistical variance of the difference values is calculated.On this basis,the second-order statistics of the difference values are constructed,and when the second-order statistics are minimized,the corresponding number of sources is estimated.The proposed method has wide applicability,which is suitable for both general asymptotic regime and classical asymptotic system,and is suitable for both white Gaussian noise environment and colored noise environment.The method makes up for the lack of source enumeration methods in the case of general asymptotic system and colored noise.

关键词： source enumeration general asymptotic regime colored noise diagonal loading second-order statistics

Real-time ray-based channel generation and emulation for UAV communications

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Chinese Journal of Aeronautics 2022年第9期35卷 106-116页

作者： Yang YANG Tingpeng LI Xiaomin CHEN Manxi WANG Qiuming ZHU Ruirui FENG Fuqiao DUAN Taotao ZHANG state key laboratory of complex electromagnetic environment effects on electronics and information system(cemeE) Luoyang 471003China College of Electronic and information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

A real-time ray-based hardware emulator for Unmanned Aerial Vehicle(UAV) communication channels which suits for the Three-Dimensional(3D) dynamic scenarios and considers the movements of both terminals is developed in this paper. The time-variant channel parameters, i.e.,ray delay, ray gain, and ray Doppler frequency are precalculated in the host by using the Ray Tracing(RT) method. Meanwhile, RT simulation dramatically increases the number of valid rays. To address the problem of resource limitation and huge computational burden in the implementation,an efficient ray coefficients generation method based on iteration is proposed and implemented.With the advantages of low cost and high flexibility, a Software Defined Radio(SDR) hardware platform is used to emulate the ray-based UAV channels by utilizing the compact architecture including the Time-Division(TD) scheme and Tapped-Delay Line(TDL) for channel convolution.Finally, hardware measurement results demonstrate that the properties of emulated channel, i.e.,Power Delay Profile(PDP) and Doppler Power Spectrum Density(DPSD) consist with the simulated ones, which verifies the correctness of hardware implementation. The proposed channel emulator provides an efficient way for optimization, verification, and evaluation of UAV communication systems.

关键词： Unmanned aerial vehicle Channel model Ray-based channel emulation Ray tracing Software defined radio Ray coefficient

Sequential Experiment Design Method Based on Uniformity and Distortion of Responses

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 778-790页

作者： Qian-yi HUANG Liang-wei QI Jing-ke ZHANG Yu TANG state key laboratory of complex electromagnetic environment effects on electronics and information system(cemeE) Luoyang 471003China School of Mathematical Sciences Soochow UniversitySuzhou 215006China

With the development of modern electronic countermeasure technology,the fight between radar jamming and anti-jamming in aviation military has become increasingly fierce.There are some special requirements for radar countermeasure experiments.For example,such experiments are often divided into several stages,and responses of the previous stages will become factors of the next stages.Moreover,the experiment design can only consider some typical level values of the factors.However,the experiment factors are mostly continuous variables.Thus when there are some jumps in the response,and the value granularity of the factor level is large,the responses fail to reflect the distortion process,which makes it difficult to explore the radar performance boundary.Therefore,it is necessary to study the sequential experiment design method with the optimization goals of response uniformization and response distortion process characterization.In this paper,a sequential experiment design strategy based on Kriging model is established.Firstly,Kriging model is used to fit the initial experimental data to obtain the response surface.In order to enhance the uniformity of response distribution,Shannon entropy is applied to the objective function as the measure of uniformity.While for the situation of response distortion,we consider replacing the existing experiment points with those whose corresponding responses have a larger gradient norm.It means that the response value near these points will change rapidly,so they are more valuable for research.Then we use the peak surface in the three-dimensional space to intuitively verify the effect of the above algorithms on response uniformization and response distortion process characterization,and use the simulated annealing algorithm to solve them.The simulation results show that our sequential experiment strategy has a good effect.Finally,we apply the strategy to the practical problem of radar countermeasure experiment,and the obtained results also perform well.

关键词： radar countermeasure experiments response distortion sequential experiment uniform distribution

Stepped frequency chirp signal imaging radar jamming using two-dimensional nonperiodic phase modulation

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Frontiers of information Technology & Electronic Engineering 2023年第3期24卷 433-446页

作者： Qihua WU Feng ZHAO Tiehua ZHAO Xiaobin LIU Junjie WANG Shunping XIAO state key laboratory of complex electromagnetic environment effects on electronics and information system National University of Defense TechnologyChangsha 410073China

Stepped frequency chirp signal obtains high-resolution radar images by synthesizing multiple narrowband chirp pulses.It has been one of the most commonly used wideband radar waveforms due to its lower demand for radar instant bandwidth.In this paper,we propose a radar jamming method using two-dimensional nonperiodic phase modulation against stepped frequency chirp signal imaging radar.Using the unique property of nonperiodic phase modulation,the proposed method can generate high-level sidelobes that perform as a special blanket jamming along both the range and azimuth directions and make the target unrecognizable.Then,the influence of different modulation parameters,such as the code width and duty ratio,are further discussed.Based on this,the corresponding parameter design principles are presented.Finally,the validity of the proposed method is demonstrated by the Yake-42 plane data simulation and measured unmanned aerial vehicle data experiment.

关键词： Radar jamming Stepped frequency chirp signal Nonperiodic phase modulation Wideband radar