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Ultra-wideband Waveguide-coupled Photodiodes Heterogeneously Integrated on a Thin-film Lithium Niobate Platform

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Light(Advanced Manufacturing) 2023年第3期4卷 263-271页

作者： Chao Wei Youren Yu Ziyun Wang Lin Jiang Zhongming Zeng Jia Ye Xihua Zou Wei Pan Xiaojun Xie Lianshan Yan key laboratory of photonic-electric integration and communication-sensing convergence School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu611756China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei230026China

With the advantages of large electro-optical coefficient,wide transparency window,and strong optical confinement,thin-film lithium niobate(TFLN)technique has enabled the development of various high-performance optoelectronics devices,ranging from the ultra-wideband electro-optic modulators to the high-efficient quantum ***,the TFLN platform does not natively promise lasers and *** study presents an InP/InGaAs modified uni-traveling carrier(MUTC)photodiodes heterogeneously integrated on the TFLN platform with a record-high 3-dB bandwidth of 110 GHz and a responsivity of 0.4 A/W at a 1,550-nm *** is implemented in a wafer-level TFLN-InP heterogeneous integration platform and is suitable for the large-scale,multi-function,and high-performance TFLN photonic integrated circuits.

关键词： Photodiodes Thin-film lithium niobate Integrated photonics Ultra-wideband electro-optic modulators

A 3-D Polarization Quadrature Amplitude Modulation Method and Constellation Mapping

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China communications 2015年第10期12卷 16-26页

作者： SUN Xuehong ZHANG Haiying ZENG Zhimin GUO Caili Beijing key laboratory of Network System Architecture and convergence School of Information and Communication EngineeringBeijing University of Posts and Telecommunications key laboratory of Intelligent sensing for Desert Information School of Physics Electrical EngineeringNingxia University

As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) *** can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation *** to design a feasible constellation is the most concerned problem of PQAM *** paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation ***,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for ***,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.

关键词： polarization quadrature amplitude modulation minimum euclidean distance symbol error probability 3-D constellation

A Study on The Multi-Antenna Geometrical Depolarization Channel Modeling

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China communications 2016年第3期13卷 105-114页

作者： SUN Xuehong YANG Xiaoli ZENG Zhimin ZHANG Cheng BAI Bing Beijing key laboratory of Network System Architecture and convergence School of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China key laboratory of Intelligent sensing for Desert Information School of Physics Electrical EngineeringNingxia UniversityYinchuan750021China

The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path if known the antenna configuration, the polarization field radiation pattern and the spatial distribution of scatters. With the development of communication technology, information transmission spectrum is more and more scarce. The original model provides only a single channel polarization state, so the information will be limited that the polarization state carries in the polarization modulation. The research is so significance that how to carries polarization modulation information by using multi-antenna polarization state. However, the present study shows that have no depolarization effect model for multi-antenna systems. In this paper, we propose a multi-antenna geometrical depolarization model. On the basis of a single antenna to calculate the depolarization effect of the model, and through simulation to analysis the main factors that influence the depolarization effect. This article provides a multi-antenna geometrical depolarization channel modeling that can applied to large-scale array antenna, and to some extent increase the speed of information transmission.

关键词： large-scale array antenna multi-antenna channel modeling depolarization effect cross polarization discrimination

Towards an intelligent photonic system

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Science China(Information Sciences) 2020年第6期63卷 80-96页

作者： Weiwen ZOU Bowen MA Shaofu XU Xiuting ZOU Xingjun WANG State key laboratory of Advanced Optical communication Systems and Networks Intelligent Microwave Lightwave Integration Innovation Center (iMLic) Department of Electronic EngineeringShanghai Jiao Tong University State key laboratory of Advanced Optical communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

The emerging intelligence technologies represented by deep learning have broadened their applications to various fields. Beyond the conventional electronics-based processing systems, the convergence of photonics and artificial intelligence(AI) technology enhances the performance and learning ability of AI. In this review, we propose the concept of an intelligent photonic system(IPS), illustrating it as a developing architecture with three different versions. For each version of IPS, we review several representative *** we discuss the challenges towards an IPS and provide some prospects for the future development.

关键词： intelligent photonic system deep learning artificial intelligence optical neural network neuromorphic photonics

Space-based information service in Internet Plus Era

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Science China(Information Sciences) 2017年第10期60卷 229-238页

作者： Deren LI Xin SHEN Nengcheng CHEN Zhifeng XIAO State key laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan University

"Internet Plus" represents a new form of society that provides a vast platform for reform, innovation,and development. Given the continued integration of the Internet in many fields, Internet Plus is profoundly transforming and influencing a variety of traditional industries. Internet Plus has created conditions favorable for the transformation of earth observation and satellite navigation into an intelligent and real-time geospatial information service. The authors propose that in order to implement continuous, all-weather, all-terrain services for the specific purposes of each individual, it will be necessary to overcome the flaws in existing space-based information systems, such as limited regional coverage, slow response, and weak interoperability. Furthermore, to meet the Big Data Era’s geospatial information service requirements, an "Internet Plus Space-Based Information Service" system, intrinsically linked to ground Internet networks, will have to be constructed. With reference to the developments of aerospace information technology, this paper discusses three levels of the proposed structure of the Internet Plus space-based information service system and ideas for its implementation. Finally,in recognition of the demands facing the Internet Plus space-based information service system, the prospects for geomatics and important supporting technologies are examined.

关键词： Internet Plus space-based information service space information network satellite remote sensing satellite navigation satellite communication

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

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian Guo Kunpeng Li Wei Yue Nam‑Young Kim Yang Li Guozhen Shen Jong‑Chul Lee Department of Electronic convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea Department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State key laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction

Link Maintenance Scheme for OFDM-Based Cognitive Radio Ad Hoc Networks

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China communications 2015年第10期12卷 42-51页

作者： LI Jingye LUO Tao LIU Xuelian YUE Guangxin Beijing key laboratory of Network System Architecture and convergence Beijing University of Posts and Telecommunications

Transmission among the cognitive users(CUs)' is always interrupted by the primary users(PUs)' reclaim of the spectrum and the fading effect of wireless *** maintain reliable continuous communication among CUs,an efficient scheme for link maintenance in OFDM-based cognitive radio Ad Hoc networks is proposed in this *** the scheme,redundant sub-channels(RSC) are employed by CUs to tackle the outage problem caused by the PUs' reclaim of the spectrum and wireless fading effect in the ***,backup sub-channels(BSC) are arranged to help select sub-channels with better channel ***,to lower the overhead and improve the accuracy of the spectrum sensing,a partial sensing module is designed to enable the CUs to inherit and update the original idle spectrum list until it *** results show that the proposed scheme can realize higher throughput and lower sensing overhead with slight reduction of the forced termination probability(FTP) performance compared to the existing approaches.

关键词： cognitive radio link maintenance sensing overhead

On-line learning algorithm for dynamic sensitivity control in IEEE 802. 11ax network

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The Journal of China Universities of Posts and Telecommunications 2018年第5期25卷 67-74页

作者： Li Qishan Hu Zhiqun Wen Xiangming Lu Zhaoming Qi Hang School of Information and communication Engineering Beijing University of Posts and Telecommunications Beijing key laboratory of Network System Architecture and convergence Beijing University of Posts and Telecommunications Beijing laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications

The popularity of IEEE 802. 11 based wireless local area network（ WLAN） increased significantly in recent years and resulted in the dense deployment of WLANs. While densification can contribute to increasing coverage,it could also lead to increasing interference and cannot insure high spatial reuse due to the current physical carrier sensing of IEEE 802. 11. To tackle these challenges,the dynamic sensitivity control（ DSC） is considered in IEEE802. 11 ax,which dynamically selects the appropriate carrier sensing threshold（ CST） to improve spectrum efficiency and enhance spatial reuse in densely deployed network. A dynamic Q-learning based CST selection method is proposed to enable a network to select the optimal CST according to the channel condition. Simulation results show that the proposed scheme provides 40% aggregate throughput gain of a dense network when compared with legacy IEEE 802. 11.

关键词： IEEE 802. llax reinforcement learning dynamic sensitivity control dense network