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Radar Cross-Section Measurement Using the Near-Field Single-Frequency Angular-Diversity Technique

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Journal of Systems Engineering and Electronics 2000年第1期11卷 1-7页

作者： Ye, Xiaodong Fang, Dagang sheng, weixing Nanjing Univ of Science and Technology Nanjing China

Radar cross-section (RCS) measurement with the near-field electromagnetic wave illumination of a target has been proved to be practical. The existing methods employ the multiplefrequency angular-diversity (MFAD) technique, whereas this paper considers the single-frequency angular-diversity (SFAD) technique. The paper takes into account the scattering center modeling and the limitation of higher sidelobes in reconstructing images in the SFAD technique compared to the MFAD technique. A method of combining the SFAD technique with the RELAX approach is presented for the high-resolution extraction of scattering centers on a target. The proposed method offers an excellent RCS recovery, which is validated by numerical results.

关键词： Electromagnetic wave scattering Image reconstruction Radar imaging Radar target recognition Relaxation processes

Phase-only pattern synthesis based on gradient-descent optimization

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Journal of Systems Engineering and Electronics 2016年第2期27卷 297-307页

作者： Chengjun Lu weixing sheng Yubing Han Xiaofeng Ma School of Electronic and Optical Engineering Nanjing University of Science and Technology

By applying phase-only technique in array antenna pattern synthesis, antenna arrays can form desired patterns with the use of phase shifters only. A novel phase-only pattern synthesis algorithm is proposed for the passive phased array seeker. This algorithm synthesizes the main beam of the antenna pattern through least-squares approximation, thus minimizing the errors between the actual and the desired main beams. The synthesis problem can be solved by applying gradient-descent optimization. The item for suppressing side lobes is added to the above synthesis problem. To obtain a side lobe level as low as possible, the algorithm assigns different weights to different directions in the side lobe region. The algorithm is run repeatedly and the weights are adjusted adaptively according to the normalized power in the side lobe directions. Detailed examples are presented to demonstrate the accuracy and effectiveness of the proposed approach.

关键词： pattern synthesis phase-only gradient-descent adaptively

Shaped-Beam Pattern Synthesis Through the Construction of Weighted Generalized Rayleigh Quotient

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Chinese Journal of Electronics 2019年第1期28卷 207-214页

作者： YANG Yin WAN Chuan sheng weixing HAN Yubing MA Xiaofeng School of Electronic and Optical Engineering Nanjing University of Science and Technology

A novel shaped-beam pattern synthesis method of generating an arbitrary footprint pattern under an arbitrary array structure is proposed. The embedded element pattern information is included in the pattern model, and a new cost function composed of three optimization items which are sidelobe levels,mainlobe ripples and mainlobe gains is constructed through the model. During the optimization process,to further enhance the performance of the synthesized pattern, a weight matrix is designed and added to the optimization items, then the generalized Rayleigh quotient approximation method is used to obtain the final array element excitations. To illustrate the good performance of the provided method, several synthesis examples with different arrays and footprints are presented. Compared with other algorithms such as Weighted alternating reverse projection(WARP) method, the proposed method can achieve better results with lower sidelobe levels, smaller mainlobe ripples and less computational load.

关键词： Pattern synthesis Embedded element pattern Mutual coupling Generalized Rayleigh quotient approximation Arbitrary footprint

Adaptive monopulse beamforming with partial parallel structure

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Journal of Systems Engineering and Electronics 2012年第6期23卷 802-814页

作者： Liang Chen weixing sheng Xiaofeng Ma Fei Huang and Yubing Han School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing 210094 P. R. China

A new recursive algorithm with the partial parallel structure based on the linearly constrained minimum variance （LCMV） criterion for adaptive monopulse systems is proposed. The weight vector associated with the original whole antenna array is decomposed into several adaptive weight sub-vectors firstly. An adaptive algorithm based on the conventional LCMV principle is then deduced to update the weight sub-vectors for sum and difference beam, respectively. The optimal weight vector can be obtained after convergence. The required computational complexity is evaluated for the proposed technique, which is on the order of O（N） and less than that of the conventional LCMV method. The flow chart scheme with the partial parallel structure of the proposed algorithm is introduced. This scheme is easy to be implemented on a distributed computer/digital signal processor （DSP） system to solve the problems of the heavy computational burden and vast data transmission of the large-scale adaptive monopulse array. Then, the monopulse ratio and convergence rate of the proposed algorithm are evaluated by numerical simulations. Compared with some recent adaptive monopulse estimation methods, a better performance on computational complexity and monopulse ratio can be achieved with the proposed adaptive method.

关键词： digital beamforming monopulse estimation linearlyconstrainted minimum variance (LCMV) parallel distributed com-putation.

Signal recovery method based on co-prime array

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Journal of Systems Engineering and Electronics 2017年第2期28卷 224-234页

作者： Shuang Qiu weixing sheng Xiaofeng Ma Yubing Han Renli Zhang School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A signal waveform recovery method based on the co-prime array is investigated to extract the waveform of the desired signal from spatial interferences in narrowband scenarios. The direction of arrivals (DOAs) of the desired signal and interference signals are estimated with the compressive sensing approach based on angle grids, and the signal power together with the noise power are estimated. Thereafter, a modified steepest descent (SD) method is derived to recover the waveform of the desired signal and interferences utilizing the estimated power and directions. The recovered waveform of the desired signal is the output of the proposed method. The situation in which the signals are not on the predefined angle grids is also considered. The DOAs estimated via the predefined angle grids are corrected based on the maximum likelihood (ML) angle estimation. Compared to the existing beamforming methods on co-prime array, the proposed method can obtain the waveform of the desired signal. Simulation results demonstrate that the proposed method can achieve good performance in signal waveform recovery and output signal to noise ratio. © 2017 Beijing Institute of Aerospace Information.

关键词： Compressed sensing Maximum likelihood Maximum likelihood estimation Recovery Signal reconstruction Signal to noise ratio

Hybrid interference alignment and power allocation for multi-user interference MIMO channels

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Science China(Information Sciences) 2013年第4期56卷 19-27页

作者： SHU Feng YOU XiaoHu WANG Mao HAN YuBing LI Yang sheng weixing Institute of Wireless Communication and Sensor Network EEOTNanjing University of Science and Technology National Mobile Communications Research Laboratory Southeast University Department of Electrical Engineering University of Texas at DallasTX 75080-3021TexasUSA

This paper proposes a hybrid interference alignment scheme which combines maximizing signal-toleakage-noise ratio(Max-SLNR) at transmitter and maximizing signal-to-interference-noise ratio(Max-SINR) at *** proposed scheme gives the same sum rate as the existing method using Max-SINR at both transmitter and receiver by avoiding the operation of reversing channel,thus it provides a simpler ***,two power allocation procedures are devised based on game theory and water *** gain of these schemes over equal power allocation increases to 2 bit/s/Hz in correlated fading channels as large-scale fading becomes ***,user fairness is solved by introducing weighting factors.

关键词： interference alignment power allocation sum rate Max-SLNR Max-SINR

High linearity U-band power amplifier design:a novel intermodulation point analysis method

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Frontiers of Information Technology & Electronic Engineering 2023年第1期24卷 176-186页

作者： Jie CUI Peipei LI weixing sheng School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A power amplifier’s linearity determines the emission signal’s quality and the efficiency of the *** distortion can result in system bit error,out-of-band radiation,and interference with other channels,which severely influence communication system’s quality and *** from the third-order intermodulation point of the milimeter wave(mm-Wave)power amplifiers,the circuit’s nonlinearity is compensated *** analysis,design,and implementation of linear class AB mm-Wave power amplifiers based on GlobalFoundries 45 nm CMOS silicon-on-insulator(SOI)technology are *** single-ended and differential stacked power amplifiers have been implemented based on cascode cells and triple cascode cells operating in U-band *** to nonlinear analysis and on-wafer measurements,designs based on triple cascode cells outperform those based on cascode *** single-ended measurements,the differential power amplifier achieves a measured peak power-added efficiency(PAE)of 47.2%and a saturated output power(P_(sat))of 25.2 dBm at 44 *** amplifier achieves a P_(sat)higher than 23 dBm and a maximum PAE higher than 25%in the measured bandwidth from 44 GHz to 50 GHz.

关键词： CMOS silicon-on-insulator(SOI) Linearity analysis Milimeter wave(mm-Wave) Power amplifier

High-sum-rate beamformers for multi-pair two-way relay networks with amplify-and-forward relaying strategy

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Science China(Information Sciences) 2014年第2期57卷 122-132页

作者： SHU Feng LU YaZhe CHEN Yu YOU XiaoHu WANG JianXin WANG Mao sheng weixing CHEN Qian School of Electronic and Optical Engineering Nanjing University of Science and Technology National Mobile Communications Research Laboratory Southeast University

In multi-pair two-way relay networks,the control over inter-pair-interference is a challenging *** mobile stations(MSs)cooperate fully,to achieve the sum capacity of networks and at the same time completely remove the inter-pair-interference,a singular value decomposition(SVD)based beamforming scheme at relay station(RS)is established where SVD beamformers are applied over both uplink and downlink channels,*** avoid any cooperation among users,an efcient beamforming scheme is *** scheme uses the Max-SINR based receive beamformer at RS in uplink channel and the Max-SLNR based transmit precoder at RS in downlink *** omits interference(uplink)and leakage(donwlink)inside each pair of users due to their abilities of self-interference *** beamforming scheme provides an analytical solution like some well-known linear beamformers such as zero-forcing,block diagonalization,*** simulation,we find:the proposed SVD shows an excellent sum-rate performance at the expense of a large cooperation overhead at MSs and can be used as a tighter upper bound of sum-rate;the proposed scheme of Max-SINR beamformer plus Max-SLNR precoder performs much better on sum-rate than the ZF-based and the BD-based schemes by using almost the same computational amount.

关键词： multipair two-way relay beamforming SVD Max-SLNR Max-SINR average sum rate upper bound MAC

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多层自适应交叉近似加速的旋转对称体矩量法

电波科学学报 2014年第1期29卷 55-60,71页

作者：苏杨南华盛卫星南京理工大学电子工程与光电技术学院江苏南京210094 试验物理与计算数学国家重点实验室北京100076

为了更有效地分析旋转对称电大物体的电磁散射问题,提出了一种针对旋转对称矩量法的多层自适应交叉近似加速方法,并分别应用于基于三角形基函数和3阶Hermite基函数的旋转对称矩量法.使用所提方法加速混合场积分方程下旋转对称体矩量法... 详细信息

为了更有效地分析旋转对称电大物体的电磁散射问题,提出了一种针对旋转对称矩量法的多层自适应交叉近似加速方法,并分别应用于基于三角形基函数和3阶Hermite基函数的旋转对称矩量法.使用所提方法加速混合场积分方程下旋转对称体矩量法的单模式与多模式阻抗矩阵的构建过程时,计算得到的远场雷达散射截面积与传统旋转对称矩量法的结果吻合良好,且计算效率明显提高.

关键词：旋转对称矩量法多层自适应交叉近似三角形基函数 3阶Hermite基函数混合场积分方程