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Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSRWTC)

作者： Yu-Lu Lei Ji-Tao Yang Chao-Hai Du Center for Carbon-based Electronics School of Electronics Peking University State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University

ISBN: (数字)9798331507794

ISBN: (纸本)9798331507800

The challenge of engineering and manipulating the electromagnetic (EM) properties of materials has long been a central focus in materials science and engineering. Among various strategies, materials with near-zero refractive indices have garnered significant interest due to their diverse applications in controlling EM waves. However, few studies have examined the effects of periodic arrangements on these materials. This study investigates the integration of photonic doping within a periodic epsilon-near-zero (ENZ) waveguide to elucidate the unique properties of Smith-Purcell radiation (SPR) at 5.8 GHz. By employing a structure with a relative permittivity of 37, we achieve uniform input signal phases across the ENZ medium and realize cloaking. Our findings reveal a coherent phase relationship between incident and output waves, paving the way for potential cloaking applications that prioritize fabrication simplicity and cost-effectiveness, even in hard-to-reach regimes. This research not only enhances our understanding of periodic ENZ structures but also opens new avenues for innovative applications in electromagnetic wave manipulation.

关键词： Wireless communication Fabrication Electric potential Electromagnetic scattering Electromagnetic waveguides Doping Permittivity Electromagnetics Photonics Periodic structures

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Multi-target Detection for Reconfigurable Holographic Surfaces Enabled Radar

arXiv

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arXiv 2024年

作者： Zhang, Xiaoyu Zhang, Haobo Deng, Ruoqi Liu, Liang Di, Boya State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University Beijing China The Hong Kong Polytechnic University Hong Kong

Multi-target detection is one of the primary tasks in radar-based localization and sensing, typically built on phased array antennas. However, the bulky hardware in the phased array restricts its potential for enhancing detection accuracy, since the cost and power of the phased array can become unaffordable as its physical aperture scales up to pursue higher beam shaping capabilities. To resolve this issue, we propose a radar system enabled by reconfigurable holographic surfaces (RHSs), a novel meta-surface antenna composed of meta-material elements with cost-effective and power-efficient hardware, which performs multi-target detection in an adaptive manner. Different from the phase-control structure in the phased array, the RHS is able to apply beamforming by controlling the radiation amplitudes of its elements. Consequently, traditional beamforming schemes designed for phased arrays cannot be directly applied to RHSs due to this structural difference. To tackle this challenge, a waveform and amplitude optimization algorithm (WAOA) is designed to jointly optimize the radar waveform and RHS amplitudes in order to improve the detection accuracy. Simulation results reveal that the proposed RHS-enabled radar increases the probability of detection by 0.13 compared to phased array radars when six iterations of adaptive detection are performed given the same hardware cost. Copyright © 2024, The Authors. All rights reserved.

关键词： Beamforming

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Radius Error Effect Studies of Bipolar Spherical Resonator Cavity on SLED

Radius Error Effect Studies of Bipolar Spherical Resonator C...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Zi-Li Jiang Zi-Wen Zhang Chao-Hai Du Center for Carbon-based Electronics State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University

The bipolar spherical cavity SLED has been widely used in accelerator and high power microwave fields as it has high quality factor and is much tighter in volume than the traditional structure. However, due to its high compactness, small radius changes will lead to significant changes in the system's performance. Therefore, we study the radius error effects of the bipolar spherical resonator on SLED through theoretical analysis and numerical simulation. We conclude that if the radius of the sphere is symmetrically larger or smaller only on the axis of mode rotation, the resonant frequency of the spherical cavity will be correspondingly smaller or larger, and the change of the radius will not cause reflection. However, when the radius of the sphere changes asymmetrically perpendicular to the axis of mode rotation, the two degenerate modes will resonate at different frequencies. Due to the characteristics of the dual polarized coupler in this case, obvious reflection will appear and this could reduce the working performance of SLED seriously.

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A self-attention armed lightweight optronic convolutional neural network for SAR target recognition

A self-attention armed lightweight optronic convolutional ne...

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IET International Radar Conference (IRC 2023)

作者： Zicheng Huang Mengyang Shi Yanru Chen Yesheng Gao State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University People's Republic of China

ISBN: (数字)9781837240982

Deep learning has made significant progress in remote sensing and target recognition in recent decades. However, as a data-driven method, its development has encountered great challenges in computing speed and power consumption. Here, we propose a self-attention armed optronic neural network (SA-OPCNN) and realize the network in the optical platform for SAR target recognition. Based on the advantage of SA-OPCNN, all computation operations are executed in optics with ultra-fast speed, low computation cost, and low space complexity. Experiments on the Moving and Stationary Target Acquisition and Recognition (MSTAR) dataset demonstrate the feasibility and scalability of the proposed lightweight SAR target recognition method.

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Scatterer Recognition for Multi-Modal Intelligent Vehicular Channel Modeling via Synesthesia of Machines

arXiv

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arXiv 2024年

作者： Huang, Ziwei Bai, Lu Han, Zengrui Cheng, Xiang The State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University Beijing100871 China Shandong University Jinan250101 China

In this paper, a novel multi-modal intelligent vehicular channel model is proposed by scatterer recognition from light detection and ranging (LiDAR) point clouds via Synesthesia of Machines (SoM). The proposed model can support the design of intelligent transportation systems (ITSs). To provide a robust data foundation, a new intelligent sensing-communication integration dataset in vehicular urban scenarios is constructed. Based on the constructed dataset, the complex SoM mechanism, i.e., mapping relationship between scatterers in electromagnetic space and LiDAR point clouds in physical environment, is explored via multilayer perceptron (MLP) in consideration of electromagnetic propagation mechanism. By using LiDAR point clouds to implement scatterer recognition, channel non-stationarity and consistency are captured closely coupled with the environment. Using ray-tracing (RT)-based results as the ground truth, the scatterer recognition accuracy exceeds 90%. The accuracy of the proposed model is further verified by the close fit between simulation results and RT results. Copyright © 2024, The Authors. All rights reserved.

关键词： optical radar

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An overview of ML-based applications for next generation optical networks

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Science China(Information Sciences) 2020年第6期63卷 31-46页

作者： Ruoxuan GAO Lei LIU Xiaomin LIU Huazhi LUN Lilin YI Weisheng HU Qunbi ZHUGE Shanghai Institute for Advanced Communication and Data Science State Key Laboratory of Advanced Optical Communication Systems and NetworksDepartment of Electronic Engineering Shanghai Jiao Tong University

Over the past few decades, the demand for the capacity and reliability of optical networks has continued to grow. In the meantime, optical networks with larger knowledge scales have become sources of numerous heterogeneous data. In order to handle these new challenges, many issues need to be resolved,among which the low-margin optical networks design, power optimization, routing and wavelength assignment(RWA), failure management are quite important. However, the use of traditional algorithms in the above four applications shows some shortcomings. Fortunately, artificial intelligence(AI), especially machine learning(ML), is regarded as one of the most promising methods to overcome these shortcomings. In this study, we review the applications of ML methods in solving these four issues. Although many ML-based researches have emerged, the applications of ML techniques in optical networks still face challenges. Therefore, we also discuss some possible future directions of investigating ML-based approaches in optical networks.

关键词： optical networks artificial intelligence machine learning system margin power optimization routing and wavelength assignment failure management

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Terahertz Edge Detection Based on All-Dielectric Metasurfaces

Terahertz Edge Detection Based on All-Dielectric Metasurface...

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Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSRWTC)

作者： Yue-Yi Zhang Yi-Bing Xiao Feng-Yuan Han Chao-Hai Du Center for Carbon-based Electronics School of Electronics Peking University State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University

ISBN: (数字)9798331507794

ISBN: (纸本)9798331507800

Signal processing is an important technique in various science and technology fields. In recent years, metasurfaces, as a kind of two-dimensional artificial materials, have been widely used in multiple fields. With its excellent capability of controlling electromagnetic wave amplitude, phase, and polarization, metasurfaces can provide an effective solution to perform large-scale and real-time data processing. In this paper, according to the properties of the Fourier transform, an all-dielectric terahertz metasurface is designed and demonstrated by simulation, which can achieve edge detection. The design method in this paper can be extended for analog data processing and other fields.

关键词： Wireless communication Fourier transforms Image edge detection Design methodology Electromagnetic scattering Signal processing Metasurfaces Data processing Vectors Real-time systems

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Speckle-based optronic convolutional neural network for SAR target recognition in light scattering imaging

Speckle-based optronic convolutional neural network for SAR ...

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IET International Radar Conference (IRC 2023)

作者： Zicheng Huang Yanru Chen Mengyang Shi Ziyu Gu Yesheng Gao State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University People's Republic of China

ISBN: (数字)9781837240982

Light scattering has been a pervasive issue in past decades across many areas. The scattering medium not only destroys the imaging performance in remote sensing but also sets challenges in automatic target recognition (ATR). Recent deep learning (DL) approaches have made significant progress in ATR tasks based on the scattered speckle patterns. However, the DL methods encounter great challenges in computation speed and power consumption. Here, we develop a speckle-based optronic convolutional neural network (S-OPCNN) and realize the network in the optical platform for SAR ATR tasks. We specifically model the speckle patterns for Moving and Stationary Target Acquisition and Recognition (MSTAR) objects by random phase noise distortion. Then we train the S-OPCNN to execute the ATR tasks based on speckle patterns. In S-OPCNN, all computational operations are performed in optics with ultra-fast speed, low energy cost, and low space complexity. Experiments on MSTAR datasets demonstrate the S-OPCNN feasibility in SAR ATR under degraded imaging conditions.

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Formation of Transverse Customized Electron Beam for Vortex Smith-Purcell Radiation

Formation of Transverse Customized Electron Beam for Vortex ...

引用

International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yu-Lu Lei Zi-Wen Zhang Chao-Hai Du Center for Carbon-based Electronics State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University

The generation of coherent and high-mode purity vortex beams carrying orbital angular momentum can be achieved through Vortex Smith-Purcell radiation from chiral plasmons. However, to selectively excite the chiral plasmons, it is necessary to generate an electron beam with a specific rotational symmetry. In this study, we propose a scheme for an electron gun that can emit an electron beam with transverse rotational symmetry by customizing the emission region of the cathode. The trajectories of the electron beams from the numerical simulations illustrate the feasibility of the proposed scheme. By employing the customized beam, plasmons with a specific topological charge can be alternatively excited and diffracted into coherent vortex free-electron radiations, thereby enabling the development of multi-mode communications and chiral detections in the terahertz band.

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Simulation Analysis of a Frequency Transfer system Based on optical Frequency Combs

Simulation Analysis of a Frequency Transfer System Based on ...

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IEEE International Symposium on Applications of Ferroelectrics (ISAF)

作者： Xinbo Li Ziyang Chen Ganbin Lu Dongrui Yu Kai Wu Bin Luo Hong Guo State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics and Center for Quantum Information Technology Peking University Beijing China

ISBN: (数字)9798350371901

ISBN: (纸本)9798350371918

The simulation of frequency transfer systems can guide the selection of experimental parameters and analysis of device noises. In this paper, we constructed a simulation platform of frequency transfer systems based on electro-optic frequency combs and used the data of link noises generated from practical experiments to simulate the system’s performance. In this simulation, the optical frequency comb (OFC) is generated by a cascading-modulated laser, and a mixer is used as the phase discriminator. The phase fluctuation of the transmitted signal is compensated by a phase modulator. The results show that the simulated stability after compensation can be improved to 6.41×10 -15 @1 s and 8×10 -18 @1000 s over 500 km of fiber considering practical link noises.

关键词： Performance evaluation Phase modulation system performance Laser noise Laser stability Stability analysis optical harmonic generation optical fiber devices Frequency control Mixers

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