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Directional modulation with distributed receiver selection for secure wireless communications

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Science china(Information Sciences) 2021年第12期64卷 215-225页

作者： Hongyan ZHANG Yue XIAO Wanbin TANG Gang WU Hong NIU Xiaotian ZHOU National Key Laboratory of Science and technology on Communications University of Electronic Science and Technology of China Science and technology on Communication Networks Laboratory The 54th Research Institute of China Electronics Technology Group Corporation

In this paper, a novel directional modulation with distributed receiver selection(DM-DRS)scheme is proposed for secure wireless communications. In DM-DRS, a particular subset of receivers is activated and part of the information bits are modulated by the index of the activation pattern, in addition to traditional digital modulation. Especially, the scrambling matrix is introduced for the sake of preventing the eavesdropping. Moreover, the performances of bit error rate(BER) in terms of the union bound for both the legitimate user and eavesdropper are respectively derived in the context of an optimal joint maximum likelihood(ML) detector, and the theoretical BER upper bounds are demonstrated to be tight by the numerical results. In the context of the discrete-input and continuous-output system, the ergodic secrecy rates of the legitimate user and the eavesdropper are obtained, the secrecy rate is also quantified. Furthermore,our numerical results exhibit that DM-DRS can achieve an increased transmission rate compared to its traditional directional modulation with cooperative receivers(DM-CR) and spatial and direction modulation(SDM) counterparts, while guaranteeing an improved BER performance.

关键词： directional modulation distributed receiver selection bit error rate secrecy rate

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An Accurate Near-Field Distance Estimation Differential Algorithm

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Chinese Journal of electronics 2022年第5期31卷 851-859页

作者： ZHAO Yan TAO Haihong CHANG Xin National Key Laboratory of Radar Signal Processing Xidian Univercity the 54th research institute China Electronics Technology Group Corporation School of electronic Engineering Xidian University

the triangular geometry is the basis of near field array accurate distance estimation *** Fisher expression of traditional distance estimation is derived by utilizing the Taylor series. To improve convergence rate and estimation accuracy, a novel iterative distance estimation algorithm is proposed with differential equations based on the triangular geometry. Firstly, its convergence performance is analysed in detail. Secondly,the selection of the initial value and the number of iterations are respectively studied. thirdly, compared with the traditional estimation algorithms by utilizing the Fisher approximation, the proposed algorithm has a higher convergence rate and estimation accuracy. Moreover, its pseudocode is presented. Finally, the experiment results and performance analysis are provided to verify the effectiveness of the proposed algorithm.

关键词： iterative methods iterative distance estimation convergence performance triangular geometry Fisher expression approximation theory convergence near-field distance estimation Fisher approximation Taylor series differential equations estimation theory

Joint TDOA and AOA location algorithm

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Journal of Systems Engineering and electronics 2013年第2期24卷 183-188页

作者： Congfeng Liu Jie Yang Fengshuai Wang institute of electronic Countermeasure Xidian University School of Communication and Information Xi'an University of Posts and Telecommunications the 54th institute of china electronics technology group Corporation

For the joint time difference of arrival（TDOA） and angle of arrival（AOA） location scene,two methods are proposed based on the rectangular coordinates and the polar coordinates,*** problem is solved perfectly by calculating the target position with the joint TDOA and AOA *** the condition of rectangular coordinates,first of all,it figures out the radial range between target and reference stations,then calculates the location of the *** the case of polar coordinates,first of all,it figures out the azimuth between target and reference stations,then figures out the radial range between target and reference stations,finally obtains the location of the ***,simulation analyses show that the theoretical analysis is correct,and the proposed methods also provide the application of the joint TDOA and AOA location algorithm with the theoretical basis.

关键词： passive location joint time difference of arrival (TDOA)and angle of arrival (AOA) location direct solution method perfor-mance analysis.

Direction-of-Arrival Method Based on Randomize-then-Optimize Approach

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Journal of electronic Science and technology 2022年第4期20卷 416-424页

作者： Cai-Yi Tang Sheng Peng Zhi-Qin Zhao Bo Jiang Science and technology on electronic Information Control Laboratory Chengdu 610036 School of electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 54th research institute of china electronics technology group Shijiazhuang 050081

the direction-of-arrival(DOA)estimation problem can be solved by the methods based on sparse Bayesian learning(SBL).To assure the accuracy,SBL needs massive amounts of snapshots which may lead to a huge computational *** order to reduce the snapshot number and computational complexity,a randomize-then-optimize(RTO)algorithm based DOA estimation method is ***“learning”process for updating hyperparameters in SBL can be avoided by using the optimization and Metropolis-Hastings process in the RTO *** apply the RTO algorithm for a Laplace prior,a prior transformation technique is *** demonstrate the effectiveness of the proposed method,several simulations are proceeded,which verifies that the proposed method has better accuracy with 1 snapshot and shorter processing time than conventional compressive sensing(CS)based DOA methods.

关键词： Compressive sensing(CS) randomize-then-optimize(RTO) single snapshot sparse signal reconstruction

Demonstration of 60 GHz millimeter-wave short-range wireless communication system at 3.5 Gbps over 5 m range

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Science china(Information Sciences) 2017年第8期60卷 70-76页

作者： Guangrong YUE Zhiqiang WANG Lei CHEN Long CHENG Junlin TANG Xianbing ZOU Yuan ZENG Lianming LI National Key Laboratory of Science and technology on Communications University of Electronic Science and Technology of China Science and technology on Information Transmission and Dissemination in Communication Networks Laboratory 54th Research Institute of China Electronics Technology Group Corporation Shanghai institute of Aerospace System Engineering School of Information Science and Engineering Southeast University

Millimeter-wave communication has received considerable attention for use in new-generation broadband wireless communication because of the scarcity of microwave band spectrum resources. the unlicensed frequency band at 60 GHz is suitable for indoor short-range broadband communication. In this paper, we introduce a 60 GHz millimeter-wave short-range wireless communication demo system adhering to the IEEE 802.11 ad standard and targeting high-definition video streaming transmission. the system uses single-carrier transmission with frequency-domain equalization. the hardware prototype consists of a 65-nm CMOS radio-frequency front-end and a baseband transceiver for the physical layer functions. Important baseband technologies such as carrier synchronization, phase noise compensation, frequency-domain equalization, and low-density parity-check decoding based on probability calculation are also discussed. the system performance is demonstrated in an experiment on high-definition video transmission, where a data rate of 3.52 Gbps is achieved with a quadrature phase-shift keying signal over a distance of 5.109 m.

关键词： 60 GHz millimeter-wave IEEE 802 11ad SC-FDE 65-nm CMOS

Phased Array Feed Experiments and Galactic HI Observations

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research in Astronomy and Astrophysics 2023年第8期23卷 297-307页

作者： B.Liu H.W.Xi D.J.Ding Z.W.Wang S.H.Yu Y.Zhu L.Yu X.Zhang J.L.Li L.J.Liu Q.Su Y.Wu C.J.Jin B.Peng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Radio Astronomy and technology Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China the 54th research institute of china electronic technology group cooperation Shijiazhuang 050081China

the Phased Array Feed(PAF)is considered as one of the next generation receivers for radio telescopes,which can significantly enlarge the instantaneous Field-of-View of large aperture single dish radio telescopes and enable more flexible observing *** efforts on PAF development for radio telescopes have been made for more than two decades and have become more and more *** report the development of an ambient-temperature 19 element L-band PAF system and the experimental results including its far field beam pattern and system temperature measurement,which achieve the *** the aperture array beam-forming method,we demonstrate a wide-field Galactic HI observations in the radio camera *** results indicate that this system might be applicable for strong Galactic transient *** system could be directly equipped to large telescopes like the Five-hundred-meter Aperture Spherical radio Telescope(FAST)and FAST array in the future.

关键词： instrumentation detectors-techniques imaging spectroscopy-line profiles

Multimodality-based Wind Speed Forecasting Method for the Wind Resistance Control of Large Radio Telescope

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research in Astronomy and Astrophysics 2023年第9期23卷 20-28页

作者： Wen-Juan Wang Bao-Qing Han Long-Yang Wang Tian Luan Yue-Fei Yan Wu-Lin Zhao De-Qing Kong Yang Wu Cong-Si Wang Key Laboratory of electronic Equipment Structure Design Ministry of EducationXidian UniversityXi’an 710071China the 39th research institute of china electronics technology group Corporation Xi’an 710065China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China the 54th research institute of china electronics technology group Corporation Shijiazhuang 050081China Guangzhou institute of technology Xidian UniversityGuangzhou 510555China

A large,fully steerable radio telescope is susceptible to the wind load,leading to structure deformation andpointing deviation of the *** effectively suppress the influence of dynamic wind load,the wind resistancecontrol of the telescope is carried out based on wind speed *** study developed a wind speedforecasting model to efficiently forecast the wind speed at the telescope *** proposed model successfullyeliminates the random noise of the original wind speed,effectively extracts the wind speed features and solves theautomatic optimization of the hyperparameters of the forecasting *** model significantly improves theaccuracy and reliability of wind speed *** verify the forecasting performance of the proposed model,the wind data from the Qitai Radio Telescope site is examined as a case *** wind speed forecasting model’sMAE,RMSE and MAPE are 0.0361,0.0703 and 3.87%,*** performance of the proposed modelmeets the requirements of wind resistance control and can provide data support for the radio telescope.

关键词： telescopes-methods numerical-methods data analysis

Adaptive support vector machine decision feedback equalizer

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Journal of Systems Engineering and electronics 2011年第3期22卷 452-461页

作者： Sumin Zhang Shu Li Donglin Su School of electronic and Information Engineering Beihang UniversityBeijing 100191P.R.China the 54th institute of china electronics technology group Corporation Shijiazhuang 050081P.R.China nstitute of Land-air Defense Equipment Beijing 100085P.R.China

An adaptive support vector machine decision feedback equalizer（ASVM-DFE） based on the least square support vector machine（LS-SVM） is proposed,it solves linear system iteratively with less computational *** adaptive non-singleton fuzzy support vector machine decision feedback equalizer（ANSFSVMDFE） is also presented,it adopts the non-singleton fuzzy Gaussian kernel function with similar characteristic of pre-filter and is modified with a space transformation based *** under nonlinear time variant channels show that ASVM-DFE and ANSFSVM-DFE perform very well on nonlinear equalization and ANSFSVM-DFE acts especially well in resisting abrupt interference.

关键词： non-singleton fuzzy system support vector machine(SVM) equalizer decision feedback.

Wideband spectrum sensing using step-sampling based on the multipath nyquist folding receiver

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Defence technology（防务技术） 2024年第1期31卷 523-536页

作者： Kai-lun Tian Kai-li Jiang Sen Cao Jian Gao Ying Xiong Bin Tang Xu-ying Zhang Yan-fei Li University of electronic Science and technology of china Chengdu611731China china electronics technology group Corporation 29th research institute Chengdu610036China

Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical *** Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spectrum sensing,which is subject to the complexity of processing the modulated *** this case,a multipath NYFR architecture with a step-sampling rate for the different paths is *** different numbers of digital channels for each path are designed based on the Chinese remainder theorem(CRT).then,the detectable frequency range is divided into multiple frequency grids,and the Nyquist zone(NZ) of the input can be obtained by sensing these ***,high-precision parameter estimation is performed by utilizing the NYFR *** with the existing methods,the scheme proposed in this paper overcomes the challenge of NZ estimation,information damage,many computations,low accuracy,and high false alarm *** simulation experiments verify the effectiveness of the proposed architecture in this paper.

关键词： Wideband spectrum sensing Sub-Nyquist sampling Step-sampling Nyquist folding receiver(NYFR) Multisignal processing