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Super-resolution DOA estimation for correlated off-grid signals via deep estimator

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Journal of Systems Engineering and Electronics 2022年第6期33卷 1096-1107页

作者： WU Shuang yuan Ye ZHANG Weike yuan naichang Facility Design and Instrumentation Institute China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

This paper develops a deep estimator framework of deep convolution networks(DCNs)for super-resolution direction of arrival(DOA)*** addition to the scenario of correlated signals,the quantization errors of the DCN are the major *** our deep estimator framework,one DCN is used for spectrum estimation with quantization errors,and the remaining two DCNs are used to estimate quantization *** propose training our estimator using the spatial sampled covariance matrix directly as our deep estimator’s input without any feature extraction ***,we reconstruct the original spatial spectrum from the spectrum estimate and quantization errors ***,the feasibility of the proposed deep estimator is analyzed in detail in this *** the deep estimator is appropriately trained,it can recover the correlated signals’spatial spectrum fast and *** results show that our estimator performs well in both resolution and estimation error compared with the state-of-the-art algorithms.

关键词： off-grid direction of arrival(DOA)estimation deep convolution network(DCN) correlated signal quantization error super-resolution

A method of improving SFDRs of 1-bit signals for a monobit receiver

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Journal of Systems Engineering and Electronics 2022年第2期33卷 330-339页

作者： JI Pengfei SHI Qingzhan LV Huan yuan naichang School of Electronic Sciences National University of Defense TechnologyChangsha 410073China

This paper proposes a method to improve the spu-rious-free dynamic ranges(SFDRs)of 1-bit sampled signals greatly,which is very beneficial to multi-tone signals ***,the relationship between the fundamental component and the third harmonic component of 1-bit sampled signals is analyzed for determining four contiguous special frequency bands,which do not contain any third harmonics inside and co-ver 77.8%of the whole Nyquist sampling frequency ***,we present a special 4-channel monobit receiver model,where appropriate filter banks are used to obtain four desired pass bands before 1-bit quantization and each channel can sample and process sampled data independently to achieve a good in-stantaneous dynamic range without sacrificing the real-time per-formance or computing *** simulation results show that the proposed method effectively eliminates the effect of the most harmonics on SFDRs and the mean SFDR is increased to to 20 ***,the multi-signals simulation results indicate that the maximum amplitude separation(dynamic range)of two signals in each channel is 12 dB while the proposed monobit re-ceiver can deal with up to eight simultaneous arrival *** general,the designing method proposed in this paper has a po-tential engineering value.

关键词： 1-bit signal monobit third harmonic component spurious-free dynamic range(SFDR)

宽带跳频TDMA辐射源网群的定位及网群划分方法

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系统工程与电子技术 2024年第6期46卷 1838-1846页

作者：张曦蒙马育红胡卫东王青平季鹏飞袁乃昌国防科技大学电子科学学院湖南长沙410073 中国电子科技集团公司第十研究所四川成都610036

为了解决现有方法难以对宽带跳频时分多址(frequency hopping-time division multiple access,FH-TDMA)辐射源网群定位的问题,提出一种仅利用波达方向(direction of arrival,DOA)信息的多站定位及网群划分方法。首先通过模拟滤波对各站... 详细信息

为了解决现有方法难以对宽带跳频时分多址(frequency hopping-time division multiple access,FH-TDMA)辐射源网群定位的问题,提出一种仅利用波达方向(direction of arrival,DOA)信息的多站定位及网群划分方法。首先通过模拟滤波对各站接收到的信号进行频段划分,通过基于多相滤波的数字信道化方法把信号输出到多个信道中;然后通过直接定位(direct position determination,DPD)算法计算得出各时隙辐射源的位置;最后先通过不同参数的基于密度的噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)算法选择出最佳的辐射源定位结果,再根据提出的基于先验信息的改进K-means聚类算法进行网群划分。所提方法实现了采样率和信号处理速率的降低,且无需站间严格的时间同步。结果表明,所提方法有效估计出了辐射源的数量、位置,以及网群划分情况。

关键词：辐射源定位网群划分群目标跳频时分多址

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Performance analysis of multi-group three-tuple cross-eye jamming

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Journal of Systems Engineering and Electronics 2022年第1期33卷 80-90页

作者： CHEN Jiabei SHI Qingzhan HUANG Zhaoyu WANG Qingping yuan naichang State Key Laboratory of Complex Electromagnetic Environmental Effects of Electronics and Information System National University of Defense TechnologyChangsha 410000China

Monopulse radar is widely used in *** monopulse radar has always been a research hotspot in electronic warfare(EW).Cross-eye jamming has always been considered as the most effective measures to jam with monopulse *** this paper, we propose a multi-group three-tuple crosseye jamming structure where each group contains three antenna elements with a definite phase and an amplitude ***, based on the principle of monopulse angle measurement, the error angle is deduced *** show that such a multi-group three-tuple cross-eye jamming structure performs better than the multi-element cross-eye jamming structure previously proposed, and the analysis of the centroid shows that the centroid of the structure proposed in this paper is more widely distributed in space.

关键词： electronic warfare(EW) angular deception jamming cross-eye jamming three-tuple antenna array near field

Intelligent optimization methods of phase-modulation waveform

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Journal of Systems Engineering and Electronics 2022年第4期33卷 916-923页

作者： SUN Jianwei WANG Chao SHI Qingzhan REN Wenbo YAO Zekun yuan naichang College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

With the continuous improvement of radar intelligence, it is difficult for traditional countermeasures to achieve ideal results. In order to deal with complex, changeable, and unknown threat signals in the complex electromagnetic environment, a waveform intelligent optimization model based on intelligent optimization algorithm is proposed. By virtue of the universality and fast running speed of the intelligent optimization algorithm, the model can optimize the parameters used to synthesize the countermeasure waveform according to different external signals, so as to improve the countermeasure *** algorithm(GA) and particle swarm optimization(PSO)are used to simulate the intelligent optimization of interruptedsampling and phase-modulation repeater waveform. The experimental results under different radar signal conditions show that the scheme is feasible. The performance comparison between the algorithms and some problems in the experimental results also provide a certain reference for the follow-up work.

关键词： waveform optimization intelligent optimization phase-modulation genetic algorithm(GA) particle swarm optimization(PSO)

Perfectly matched layer implementation for ADI-FDTD in dispersive media

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Journal of Systems Engineering and Electronics 2006年第1期17卷 80-84页

作者： Wang Yu yuan naichang School of Electronic Science and Engineering National Univ. of Defense Technology Changsha 410073 P. R. China

Alternating direction implicit finite difference time domain （ADI-FDTD） method is unconditionally stable and the maximum time step is not limited by the Courant stability condition, but rather by numerical error. Compared with the conventional FDTD method, the time step of ADI-FDTD can be enlarged arbitrarily and the CPU cost can be reduced. 2D perfectly matched layer （PML） absorbing boundary condition is proposed to truncate computation space for ADI-FDTD in dispersive media using recursive convolution（RC） method and the 2D PML formulations for dispersive media are derived. ADI-FDTD formulations for dispersive media can be obtained from the simplified PML formulations. The scattering of target in dispersive soil is simulated under sine wave and Gaussian pulse excitations and numerical results of ADI-FDTD with PML are compared with FDTD. Good agreement is observed. At the same time the CPU cost for ADI-FDTD is obviously reduced.

关键词： perfectly matched layer alternating direction implicit finite difference time domain dispersive media

Calculation of angular glint in near field utilizing graphical electromagnetic computing

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Journal of Systems Engineering and Electronics 2013年第6期24卷 906-911页

作者： Guangfu Zhang Chao Wang Liguo Liu Yunqi Fu naichang yuan School of Electronic Science and Engineering National University of Defense Technology

The angular glint in the near field plays an important role on radar tracking errors. To predict it more efficiently for electrically large targets, a new method based on graphical electromagnetic computing （GRECO） is proposed. With the benefit of the graphic card, the GRECO prediction method is faster and more accurate than other methods. The proposed method at the first time considers the special case that the targets cannot be completely covered by radar beams, which makes the prediction of radar tracking errors more self-contained in practical circumstances. On the other hand, the process of the scattering center extraction is omitted, resulting in possible angular glint prediction in real time. Comparisons between the simulation results and the theoretical ones validate its correctness and value to academic research and engineering applications.

关键词： angular glint near field tracking error graphical electromagnetic computing (GRECO)

A transceiver frequency conversion module based on 3D micropackaging technology

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Journal of Systems Engineering and Electronics 2020年第5期31卷 899-907页

作者： LIU Boyuan WANG Qingping WU Weiwei yuan naichang School of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China

The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-band is realized by combining with the local oscillator and the power control circuit to complete functions such as amplification, filtering and gain. In order to achieve the performance optimization and a high level of integration of the Ku-band monolithic microwave integrated circuits(MMIC) operating chip, the 3 D vertical interconnection micro-assembly technology is used. By stacking solder balls on the printed circuit board(PCB), the technology decreases the volume of the original transceiver to a miniaturized module. The module has a good electromagnetic compatibility through special structure designs. This module has the characteristics of miniaturization, low power consumption and high density, which is suitable for popularization in practical application.

关键词： Ku-band frequency conversion 3D packaging chip electromagnetic compatibility

Loaded-frequency selective surface

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Frontiers of Electrical and Electronic Engineering in China 2008年第1期3卷 96-98页

作者： Qiang GAO Dunbao YAN Yunqi FU naichang yuan Microwave Center School of Electronic Science and EngineeringNational University of Defense TechnologyChangsha 410073China

A new frequency-selective surface(FSS)with loadings is introduced in this paper and analyzed by way of period moment methods(PMMs).The simulated results show that FSS may operate in different bands and especially generate a large reduction in the resonant frequency for a fixed unit cell size through different *** provides a new orientation in the development for *** circuits are fabricated,and the measured results agree well with the simulated results.

关键词： loaded frequency selective surface(LFSS) lumped element distributed element period moment methods(PMMs)