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arXiv 2020年

作者： Yu, Wenjuan Foh, Chuan Heng Ul Quddus, Atta Liu, Yuanwei Tafazolli, Rahim 5G Innovation Centre Institute for Communication Systems University of Surrey GuildfordGU2 7XH United Kingdom School of Electronic Engineering and Computer Science Queen Mary University of London London United Kingdom

Being able to accommodate multiple simultaneous transmissions on a single channel, non-orthogonal multiple access (NOMA) appears as an attractive solution to support massive machine type communication (mMTC) that faces a massive number of devices competing to access the limited number of shared radio resources. In this paper, we first analytically study the throughput performance of NOMA-based random access (RA), namely NOMA-RA. We show that while increasing the number of power levels in NOMA-RA leads to a further gain in maximum throughput, the growth of throughput gain is slower than linear. This is due to the higher-power dominance characteristic in power-domain NOMA known in the literature. We explicitly quantify the throughput gain for the very first time in this paper. With our analytical model, we verify the performance advantage of the proposed NOMA-RA scheme by comparing with the baseline multi-channel slotted ALOHA (MS-ALOHA), with and without capture effect. Despite the higher-power dominance effect, the maximum throughput of NOMA-RA with four power levels achieves over three times that of the MS-ALOHA. However, our analytical results also reveal the sensitivity of load on the throughput of NOMA-RA. To cope with the potential bursty traffic in mMTC scenarios, we propose adaptive load regulation through a practical user barring algorithm. By estimating the current load based on the observable channel feedback, the algorithm adaptively controls user access to maintain the optimal loading of channels to achieve maximum throughput. When the proposed user barring algorithm is applied, simulations demonstrate that the instantaneous throughput of NOMA-RA always remains close to the maximum throughput confirming the effectiveness of our load regulation. Copyright © 2020, The Authors. All rights reserved.

关键词： Radio transmission

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Multi-agent Reinforcement Learning for Resource Allocation in IoT networks with Edge Computing

arXiv

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arXiv 2020年

作者： Liu, Xiaolan Yu, Jiadong Gao, Yue Department of Electronic Engineering and Computer Science Queen Mary University of London LondonE1 4NS United Kingdom Institute for Communication Systems University of Surrey GU2 7XH United Kingdom

To support popular Internet of Things (IoT) applications such as virtual reality, mobile games and wearable devices, edge computing provides a front-end distributed computing archetype of centralized cloud computing with low latency. However, it’s challenging for end users to offload computation due to their massive requirements on spectrum and computation resources and frequent requests on Radio Access Technology (RAT). In this paper, we investigate computation offloading mechanism with resource allocation in IoT edge computing networks by formulating it as a stochastic game. Here, each end user is a learning agent observing its local environment to learn optimal decisions on either local computing or edge computing with the goal of minimizing long term system cost by choosing its transmit power level, RAT and sub-channel without knowing any information of the other end users. Therefore, a multiagent reinforcement learning framework is developed to solve the stochastic game with a proposed independent learners based multi-agent Q-learning (IL-based MA-Q) algorithm. Simulations demonstrate that the proposed IL-based MA-Q algorithm is feasible to solve the formulated problem and is more energy efficient without extra cost on channel estimation at the centralized gateway compared to the other two benchmark algorithms. Copyright © 2020, The Authors. All rights reserved.

关键词： Edge computing

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Herriott-cavity-assisted all-optical atomic vector magnetometer

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Physical Review A 2020年第5期101卷 053436-053436页

作者： B. Cai C.-P. Hao Z.-R. Qiu Q.-Q. Yu W. Xiao D. Sheng Hefei National Laboratory of Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China Department of Precision Machinery and Precision Instrumentation Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of China Hefei 230027 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science and Center for Quantum Information Technology Peking University Beijing 100871 China

We report an all-optical atomic vector magnetometer using dual Bell-Bloom optical pumping beams in a Rb vapor cell. This vector magnetometer consists of two orthogonal optical pumping beams, with amplitude modulations at Rb85 and Rb87 Larmor frequencies, respectively. We simultaneously detect atomic signals excited by these two pumping beams using a single probe beam in the third direction, and extract the field orientation information using the phase delays between the modulated atomic signals and the driving beams. By adding a Herriott cavity inside the vapor cell, we improve the magnetometer sensitivity. We study the performance of this vector magnetometer in a magnetic field ranging from 100 mG to 500 mG, and demonstrate a field angle sensitivity better than 10 μrad/Hz1/2 above 10 Hz.

关键词： Atomic & molecular processes in external fields Optical pumping Zeeman effect

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Source-independent quantum random number generation with finite measurement range

Source-independent quantum random number generation with fin...

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Frontiers in Optics, FiO_2019

作者： Zheng, Ziyong Zhang, Yichen Zhao, Yijia Huang, Weinan Yu, Song Guo, Hong State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing100876 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Center for Quantum Information Technology Peking University Beijing100871 China

We present a source-independent quantum random number generator based on the measurement of quadrature of quantum optical field by applying a modified entropic uncertainty relation to circumvent the measurement range ... 详细信息

ISBN: (纸本)9781943580675

关键词： Random number generation

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Broadening flat-passband DWDM filter design based on ring-assisted silicon asymmetric Mach Zehnder Interferometer

Broadening flat-passband DWDM filter design based on ring-as...

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Asia communications and Photonics Conference

作者： Shuxian Li Haowen Shu Ming Jin Yuansheng Tao Xingjun Wang State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

A silicon based 32-channel DWDM device composed of a modified ring-assisted Mach-Zehnder filter is demonstrated. The 0.5-dB passband is over 78% within a 1.6 nm (200 GHz) channel spacing.

ISBN: (纸本)9781943580705

A silicon based 32-channel DWDM device composed of a modified ring-assisted Mach-Zehnder filter is demonstrated. The 0.5-dB passband is over 78% within a 1.6 nm (200 GHz) channel spacing.

关键词： Crosstalk Dense wavelength division multiplexing Optical directional couplers Ring resonators Silicon Wavelength division multiplexing

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Package-level passive equalization technology enabling DML-based 112 Gbps/λ PAM4 transmission

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Chinese Optics Letters 2019年第12期17卷 15-20页

作者： Zhike Zhang Jinye Li Zeping Zhao Jianguo Liu Xingjun Wang State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer SciencePeking UniversityBeijing 100871China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

We demonstrate a package-level passive equalization technology in which the wire-bonding-induced resonance effect is used to compensate for the limited gain strength within the Nyquist *** corresponding gain strength under various inductance and capacitance combinations could be quantitatively determined using a numerical *** the increase in the Nyquist frequency,the capacitance shows a greater effect on the gain strength than the ***,the parasitic capacitance should be decreased to realize the desired gain strength at a higher Nyquist *** this equalization technology,gain strength of 5.8 dB is obtained at 22 GHz,which can compensate for the limited bandwidth for the 112 Gbps pulse amplitude modulation(PAM4)*** experimental results show that 112 Gbps/λ PAM4 transmission based on a directly modulated laser(DML)module can be realized with a bit error rate of 1×10^-3 at a received optical power of 3d Bm.

关键词： passive Gbps capacitance

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Semantic communications:Theories,Technologies and Applications

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中国通信（英文版） 2024年第7期21卷前插1-前插5页

作者： Zhang Ping Shi Guangming Cui Shuguang Zhang Zhaoyang Niu Kai Xiao Yong Qin Zhijin Dai Jincheng Shao Shuo Deniz Gündüz Eleonora Grassucci School of Information and Communication Engineering at Beijing University of Posts and Telecommunications State Key Laboratory of Networking and Switching Technology IMT-2020(5G)Experts Panel Experts Panel for China's 6G development Peng Cheng Laboratory School of Artifi-cial Intelligence Xidian University electrical and computer engineering with the University of Arizona Texas A&M University UC Davis Chinese Univer-sity of Hong Kong(Shenzhen)(CUHK-Shenzhen) Zhejiang University School of Artificial Intelli-gence BUPT School of Electron-ic Information and Communications at the Huazhong University of Science and Technology(HUST) WuhanChina Peng Cheng Laboratory Guang-zhouChina and the Pazhou Laboratory(Huangpu)Guang-zhouChina Tsinghua University BeijingChina Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications School of Electronics Informa-tion and Electrical EngineeringShanghai Jiao Tong Univer-sityChina Information Processing in the Electrical and Electronic Engineering Department at Imperial College London UK Intelligent Systems and Networks Group Department at Imperial College London UK Department of Information Engineering Electronicsand Telecommunications of the Sapienza University of Rome

The last seventy years have witnessed the transi-tion of communication from Shannon's theoretical concept to current high-efficiency practical *** respect to Shannon information theory,to fulfill the high-bandwidth utilization,any further increase in the data rate requires a significant augmentation in the received signal power unless the bandwidth is extended in proportion to the incre-mental data rate.

关键词： Special issues and sections Semantics communication systems Data processing Information theory Data augmentation

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Er silicate amplifers and lasers for silicon photonics

Er silicate amplifers and lasers for silicon photonics

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Asia communications and Photonics Conference

作者： Xingjun Wang Peiqi Zhou Yandong He State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Institute of Microelectronics School of Electronics Engineering and Computer Science School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

We proposed high performance Er silicate amplifiers and lasers, based on hybrid erbium silicate-silicon nitride strip-loaded waveguides. The results provide supports and guidances for the high performance erbium silic... 详细信息

ISBN: (纸本)9781943580705

关键词： Coupled mode theory Distributed feedback lasers High power lasers Laser amplifiers Optical amplifiers Optical feedback

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Recent progress of integrated circuits and optoelectronic chips

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science China(Information sciences) 2021年第10期64卷 103-135页

作者： Yue HAO Shuiying XIANG Genquan HAN Jincheng ZHANG Xiaohua MA Zhangming ZHU Xingxing GUO Yahui ZHANG Yanan HAN Ziwei SONG Yan LIU Ling YANG Hong ZHOU Jiangyi SHI Wei ZHANG Min XU Weisheng ZHAO Biao PAN Yangqi HUANG Qi LIU Yimao CAI Jian ZHU Xin OU Tiangui YOU Huaqiang WU Bin GAO Zhiyong ZHANG Guoping GUO Yonghua CHEN Yong LIU Xiangfei CHEN Chunlai XUE Xingjun WANG Lixia ZHAO Xihua ZOU Lianshan YAN Ming LI School of Microelectronics Xidian University State Key Laboratory of Integrated Service Networks Xidian University National Integrated Circuit Innovation Center School of Microelectronics Fudan University School of Integrated Circuit Science and Engineering Beihang University China Center for Information Industry Development Frontier Institute of Chip and System Fudan University Institute of Microelectronics Peking University Nanjing Electronic Devices Institute State Key Laboratory of Functional Material for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Institute of Microelectronics Tsinghua University Center for Carbon-based Electronics Department of Electronics Peking University CAS Key Laboratory of Quantum Information University of Science and Technology of China CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Origin Quantum Computing Company Limited Key Laboratory of Flexible Electronics & Institute of Advanced Materials Nanjing Tech University State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China National Laboratory of Solid State Microstructures & College of Engineering and Applied Sciences Nanjing University State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University School of Electrical and Electronic Engineering Tiangong University Center for Information Photonics and Communications School of Information Science and TechnologySouthwest Jiaotong University School of Electronic Electrical and Communication Engineering

Integrated circuits(ICs) and optoelectronic chips are the foundation stones of the modern information society. The IC industry has been driven by the so-called "Moore's law" in the past 60 years, and now has entered the post Moore's law era. In this paper, we review the recent progress of ICs and optoelectronic chips. The research status, technical challenges and development trend of devices, chips and integrated technologies of typical IC and optoelectronic chips are focused on. The main contents include the development law of IC and optoelectronic chip technology, the IC design and processing technology, emerging memory and chip architecture, brain-like chip structure and its mechanism, heterogeneous integration, quantum chip technology, silicon photonics chip technology, integrated microwave photonic chip, and optoelectronic hybrid integrated chip.

关键词： integrated circuit semiconductor science and technology optoelectronic device and chip photonic integrated circuit wide bandgap semiconductors silicon photonics hybrid integration quantum chip integrated microwave photonic photonic neural computing

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Optical saturation characteristics of dual-and single-injection Ge-on-Si photodetectors

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Chinese Optics Letters 2018年第7期16卷 78-81页

作者：崔积适白博文杨丰赫周治平 State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

The optical saturation characteristics in the germanium-on-silicon（Ge-on-Si） photodetector are studied for the first time, to the best of our knowledge. The relationship between the optical saturation characteristics and the optical field distribution in the Ge layer is illustrated by the simulation. This theory is verified by comparative experiments with single-injection and dual-injection structures. The dual-injection photodetector with a more balanced and uniform optical field distribution has a 13% higher responsivity at low optical power and 74.4%higher saturation current at 1550 nm. At higher optical power, the bandwidth of the dual-injection photodetector is five times larger than that of the single-injection photodetector.

关键词： Ge Optical saturation characteristics of dual-and single-injection Ge-on-Si photodetectors Si

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