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Optical pulse repetition rate division using an optoelectronic oscillator

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Chinese Optics Letters 2024年第4期22卷 125-129页

作者：李平邵琨麟张亚梅潘时龙 National Key laboratory of microwave photonics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

An approach for frequency division of an optical pulse train(OPT) based on an optoelectronic oscillator(OEO) is proposed and experimentally demonstrated. When the OPT is injected into the OEO, a microwave signal with a frequency equaling fractional multiples of the repetition rate of the OPT is generated. This signal is then fed back to the OEO, maintaining its oscillation, while simultaneously serving as the control signal of a Mach–Zehnder modulator(MZM) in the OEO. The MZM acts as an optical switch, permitting specific pulses to pass through while blocking others. As a result, the repetition rate of the OPT is manipulated. A proof-of-concept experiment is carried out. Frequency division factors of 2 and 3 are successfully achieved. The phase noises of the OPT before and after the frequency division are investigated. Compared to previously reported systems, no external microwave source and sophisticated synchronization structure are needed.

关键词： frequency division optoelectronic oscillator mode-locked laser microwave photonics

Simultaneous microwave characterization of wafer-level optoelectronic transceiver chips based on photonic sampling and mapping

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Science China(Information Sciences) 2024年第2期67卷 337-338页

作者： Yutong HE Xinhai ZOU Ying XU Zhihui LI Naidi CUI Junbo FENG Yali ZHANG Zhiyao ZHANG Shangjian ZHANG Yong LIU Ninghua ZHU Research Center for microwave photonics State Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China Chongqing United Microelectronics Center (CUMEC) Xiongan Institute of Innovation Chinese Academy of Sciences

Photonic integrated circuits(PICs) promise future parallelism growths of high-performance communication, computation, and offer unprecedented bandwidth scalability with reduced power consumption as a viable replacement for an electrical wire with an optoelectronic transceiver consisting of a transmitter and a receiver integrated on the same wafer.

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Multi-focus non-periodic scanning method for femtosecond lasers based on DMD and galvanometer scanners[Invited]

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Chinese Optics Letters 2024年第5期22卷 89-94页

作者：李华明王雨胡庆磊张卓宇吕晓华曾绍群 Britton Chance Center for Biomedical photonics Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China MOE Key laboratory for Biomedical photonics Collaborative Innovation Center for Biomedical EngineeringSchool of Engineering SciencesHuazhong University of Science and TechnologyWuhan 430074China

Multi-focus parallel scanning can effectively increase laser fabrication ***,the conventional approach of using a spatial light modulator(SLM)to generate multi-foci and scan this fixed number of foci with galvanometer scanners can only achieve a periodic scanning trajectory due to the low switching speed of the *** we demonstrate a multifocus non-periodic scanning method for femtosecond lasers by using,instead,a fast-switching digital micromirror device(DMD)to generate a dynamic number of *** number of effective foci is quickly switched by introducing aberration to the undesired *** this way,the intensity allocated to each focus will not be affected by the number of foci,and a uniformity of 98%with different numbers of foci is achieved without adjusting the total laser ***,we validate the effectiveness of this scanning method by demonstrating corneal flap fabrication of porcine cornea in vitro.

关键词： multi-focus non-periodic trajectory digital micromirror device aberration control corneal cutting

Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic

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Nuclear Science and Techniques 2024年第7期35卷 101-114页

作者： Hou-Zhi Cai Qiu-Yan Luo Kai-Xuan Lin Xuan Deng Jun-Kai Liu Kai-Zhi Yang Dong Wang Jia-Jie Chen Jia-Heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu Key laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province Shenzhen Key Laboratory of Photonics and BiophotonicsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were *** camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic *** spatial resolution characteristics of the camera were studied both theoretically and *** results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the ***,the camera was used to detect the X-rays produced by the laser-targeting *** diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.

关键词： Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation

Optical multipath self-interference cancellation for a wideband in-band full-duplex system using a silicon photonic modulator chip

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Chinese Optics Letters 2024年第7期 131-136页

作者：余骁叶佳闫连山周涛朱越李鹏邹喜华潘炜 Center for Information photonics and Communications School of Information Science and Technology Southwest Jiaotong University Key laboratory of Electronic Information Control Southwest China Research Institute of Electronic Equipment microwave photonics Research laboratory School of Electrical Engineering and Computer Science University of Ottawa

We propose and experimentally demonstrate a photonic method for wideband multipath self-interference cancellation using a silicon photonic modulator chip. The chip generates phase-inverted reference signals by leveraging the opposite phase between optical sidebands. Effectively managing amplitude and phase imbalances between self-interference and reference signals, the approach rectifies discrepancies through consistent chip manufacturing and packaging *** photonic multi-dimensional multiplexing, including wavelength and polarization, enables the acquisition of multiple reference signals. Experimental results show multipath cancellation depths of 25.53 dB and 23.81 dB for bandwidths of500 MHz and 1 GHz, achieved by superimposing 2-path reference signals.

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Mode-dependent dynamic gain of all-fiber FM-EDFA under various pump manipulation

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Chinese Optics Letters 2024年第2期22卷 128-134页

作者：方翼鸿张心怡黄锡恒曾研许鸥李建平付松年秦玉文 Institute of Advanced photonics Technology School of Information EngineeringGuangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key laboratory of Information photonics Technology Guangdong University of TechnologyGuangzhou 510006China Key laboratory of Photonic Technology for Integrated Sensing and Communication Ministry of EducationGuangdong University of TechnologyGuangzhou 510006China

The dynamic gain of a few-mode erbium-doped fiber amplifier(FM-EDFA)is vital for the long-haul mode division multiplexing(MDM)***,we investigate the mode-dependent dynamic gain of an FM-EDFA under various manipulations of the pump ***,we numerically calculate the gain variation with respect to the input signal power,where a modedependent saturation input power occurs under different pump *** under the fixed intensity profile of the pump laser,the saturation input power of each spatial mode is ***,high-order mode pumping leads to a compression of the linear amplification region,even though it is beneficial for the mitigation of the differential modal gain(DMG)arising in all guided ***,we develop an all-fiber 3-mode EDFA,where the fundamental mode of the pump laser can be efficiently converted to the LP_(11)mode using the all-fiber mode-selective coupler(MSC).In comparison with the traditional LP_(01)pumping scheme,the DMG at 1550 nm can be mitigated from 1.61 dB to 0.97 dB under the LP_(11)mode pumping,while both an average gain of 19.93 dB and a DMG of less than 1 dB can be achieved from 1530 nm to 1560 ***,the corresponding signal input saturation powers are reduced by 0.3 dB for the LP_(01)mode and 1.6 dB for the LP_(11)mode,*** theoretical and experimental results indicate that a trade-off occurs between the DMG mitigation and the extension of the linear amplification range when the intensity profile of pump laser is manipulated.

关键词： few-mode erbium-doped fiber amplifier differential modal gain saturation input power

Analog spatiotemporal feature extraction for cognitive radio-frequency sensing with integrated photonics

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Light(Science & Applications) 2024年第3期13卷 478-487页

作者： Shaofu Xu Binshuo Liu Sicheng Yi Jing Wang Weiwen Zou State Key laboratory of Advanced Optical Communication Systems and Networks Intelligent Microwave Lightwave Integration Innovation Center(imLic)Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghaiChina

Analog feature extraction(AFE)is an appealing strategy for low-latency and efficient cognitive sensing systems since key features are much sparser than the Nyquist-sampled ***,applying AFE to broadband radio-frequency(RF)scenarios is challenging due to the bandwidth and programmability bottlenecks of analog electronic ***,we introduce a photonics-based scheme that extracts spatiotemporal features from broadband RF signals in the analog *** feature extractor structure inspired by convolutional neural networks is implemented on integrated photonic circuits to process RF signals from multiple antennas,extracting valid features from both temporal and spatial *** of the tunability of the photonic devices,the photonic spatiotemporal feature extractor is trainable,which enhances the validity of the extracted ***,a digital-analog-hybrid transfer learning method is proposed for the effective and low-cost training of the photonic feature *** validate our scheme,we demonstrate a radar target recognition task with a 4-GHz instantaneous *** results indicate that the photonic analog feature extractor tackles broadband RF signals and reduces the sampling rate of analog-to-digital converters to 1/4 of the Nyquist sampling while maintaining a high target recognition accuracy of 97.5%.Our scheme offers a promising path for exploiting the AFE strategy in the realm of cognitive RF sensing,with the potential to contribute to the efficient signal processing involved in applications such as autonomous driving,robotics,and smart factories.

关键词： scheme driving smart

Review of bio-inspired image sensors for efficient machine vision

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Advanced photonics 2024年第2期6卷 7-19页

作者： Wenhao Tang Qing Yang Hang Xu Yiyu Guo Jiqiang Zhang Chunfang Ouyang Leixin Meng Xu Liu Zhejiang laboratory Research Center for Frontier Fundamental StudiesHangzhouChina Zhejiang University College of Optical Science and EngineeringState Key Laboratory of Extreme Photonics and InstrumentationHangzhouChina ZJU-Hangzhou Global Scientific and Technological Innovation Center HangzhouChina Shanghai Jiao Tong University Chip Hub for Integrated Photonics Xplore(CHIPX)WuxiChina

With the rapid development of sensor networks,machine vision faces the problem of storing and computing massive *** human visual system has a very efficient information sense and computation ability,which has enlightening significance for solving the above problems in machine *** review aims to comprehensively summarize the latest advances in bio-inspired image sensors that can be used to improve machine-vision processing *** briefly introducing the research background,the relevant mechanisms of visual information processing in human visual systems are briefly discussed,including layerby-layer processing,sparse coding,and neural ***,the cases and performance of image sensors corresponding to various bio-inspired mechanisms are ***,the challenges and perspectives of implementing bio-inspired image sensors for efficient machine vision are discussed.

关键词： bio-inspired image sensor machine vision layer-by-layer processing sparse coding neural adaptation

Ship recognition based on HRRP via multi-scale sparse preserving method

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Journal of Systems engineering and Electronics 2024年第3期35卷 599-608页

作者： YANG Xueling ZHANG Gong SONG Hu College of Electronic and Information engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Lab of Radar Imaging and microwave photonics Ministry of EducationNanjing 210016China Nanjing Marine Radar Institute Nanjing 210016China

In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance.

关键词： ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction