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Joint Cooperation Clustering and Downlink Power Control for Cell-Free Massive MIMO with Deep Reinforcement Learning

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Joint Cooperation Clustering and Downlink Power Control for ...

International Conference on communication technology (ICCT)

作者： Mingjun Du Xinghua Sun Yue Zhang Junyuan Wang Pei Liu School of Electronics and Communication Engineering Sun Yat-sen University Shenzhen China Department of Electronic Information Engineering Shantou University Shantou China College of Electronic and Information Engineering Tongji University Shanghai China School of Information Engineering Wuhan University of Technology Wuhan China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China

Recently, numerous clustering and power control approaches have been developed to optimize network performance for cell-free massive multiple-input multiple-output (MIMO) systems. Notably, deep reinforcement learning (DRL) has emerged as a promising solution for network optimization. This paper investigates the joint cooperation clustering and downlink power control problem in cell-free massive MIMO, utilizing the deep deterministic policy gradient (DDPG) algorithm to maximize the long-term global average proportional fairness (PF). Our results demonstrate that the proposed DDPG method effectively outperforms the baselines in both clustering and power control. Furthermore, the proposed scheme exhibits robustness as it maintains superior performance even as the number of clusters varies.

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Outage Probability and Power Allocation Analysis of AmBC-Enabled NOMA for Future IoT

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Outage Probability and Power Allocation Analysis of AmBC-Ena...

International Conference on communication technology (ICCT)

作者： Chongye Wang Yang Liu Cheng-Xiang Wang School of Internet of Things Engineering Jiangnan University Wuxi China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing China National Mobile Communications Research Laboratory School of Information Science and Engineering Southeast University Nanjing China Purple Mountain Laboratories Nanjing China

Ambient backscatter communication (AmBC) combined with non-orthogonal multiple access (NOMA) presents superior energy reusability and higher sum rate. However, existing studies failed to utilize the information of backscatter links. Therefore, to explore the impact of backscatter link, this paper employs three-user NOMA to improve the spectral efficiency. We propose a simple distance power allocation method to accomplish successive interference cancellation. Based on the Monte Carlo method, the outage probability of the proposal is analyzed. Our work provides a scheme for coexistence between AmBC and NOMA systems in the future Internet of Things.

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A general deep reinforcement learning framework for grant-free NOMA optimization in mURLLC

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arXiv 2021年

作者： Liu, Yan Deng, Yansha Zhou, Hui Elkashlan, Maged Nallanathan, Arumugam Key Laboratory of Ministry of Education in Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China School of Electronic Engineering and Computer Science Queen Mary University of London London United Kingdom Department of Engineering King's College London London United Kingdom

Grant-free non-orthogonal multiple access (GF-NOMA) is a potential technique to support massive Ultra-Reliable and Low-Latency communication (mURLLC) service. However, the dynamic resource configuration in GF-NOMA systems is challenging due to random traffics and collisions, that are unknown at the base station (BS). Meanwhile, joint consideration of the latency and reliability requirements makes the resource configuration of GF-NOMA for mURLLC more complex. To address this problem, we develop a general learning framework for signature-based GF-NOMA in mURLLC service taking into account the multiple access signature collision, the UE detection, as well as the data decoding procedures for the K-repetition GF and the Proactive GF schemes. The goal of our learning framework is to maximize the long-term average number of successfully served users (UEs) under the latency constraint. We first perform a real-time repetition value configuration based on a double deep Q-network (DDQN) and then propose a Cooperative Multi-Agent learning technique based on the DQN (CMA-DQN) to optimize the configuration of both the repetition values and the contention-transmission unit (CTU) numbers. Our results show that the number of successfully served UEs under the same latency constraint in our proposed learning framework is up to ten times for the K-repetition scheme, and two times for the Proactive scheme, more than that with fixed repetition values and CTU numbers. In addition, the superior performance of CMA-DQN over the conventional load estimation-based approach (LE-URC) demonstrates its capability in dynamically configuring in long term. Importantly, our general learning framework can be used to optimize the resource configuration problems in all the signature-based GF-NOMA schemes. Copyright © 2021, The Authors. All rights reserved.

关键词： Deep learning

Multigrating design for integrated single-atom trapping, manipulation, and readout

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Physical Review A 2022年第5期105卷 053520-053520页

作者： Aiping Liu Jiawei Liu Wei Peng Xin-Biao Xu Guang-Jie Chen Xifeng Ren Qin Wang Chang-Ling Zou Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China State Key Laboratory of Quantum Optics and Quantum Optics Devices and Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

An on-chip multigrating device is proposed to interface single atoms and integrated photonic circuits, by guiding and focusing lasers to the area ∼10 μm above the chip for trapping, state manipulation, and readout of single rubidium atoms. For the optical dipole trap, two 850-nm laser beams are diffracted and overlapped to form the lattice of a single-atom dipole trap, with the diameter of the optical dipole trap being around 2.7 μm. Similar gratings are designed for guiding a 780-nm probe laser to excite and also collect the fluorescence of Rb87 atoms. Such a device provides a compact solution for future applications of single atoms, including the single-photon source, single-atom quantum register, and single-atom quantum sensor.

关键词： Atom optics Photonics

Asymmetric sending or not-sending twin-field quantum key distribution in practice

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arXiv 2019年

作者： Zhou, Xing-Yu Zhang, Chun-Hui Zhang, Chun-Mei Wang, Qin Institute of quantum information and technology Nanjing University of Posts and Telecommunications Nanjing210003 China "Broadband Wireless Communication and Senser Network Technology" Key Lab of Ministry of Education NUPT Nanjing210003 China "Telecommunication and Networks" National Engineering Research Center NUPT Nanjing210003 China

Quantum key distribution (QKD) offers a secret way to share keys between legitimate users which is guaranteed by the law of quantum mechanics. Most recently, the limitation of transmission distance without quantum repeaters was broken through by twin-field QKD [Nature (London) 557, 400 (2018)]. Based on its main idea, sending or not-sending (SNS) QKD protocol was proposed [Phys. Rev. A 98, 062323 (2018)], which filled the remaining security loopholes and can tolerate large misalignment errors. In this paper, we give a more general model for SNS QKD, where the two legitimate users, Alice and Bob, can possess asymmetric quantum channels. By applying the method present in the work, the legitimate users can achieve dramatically increased key generation rate and transmission distance compared with utilizing the original symmetric protocol. Therefore, our present work represents a further step along the progress of practical QKD. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum cryptography

Efficient passive measurement-device-independent quantum key distribution

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arXiv 2019年

作者： Zhang, Chun-Hui Zhang, Chun-Mei Wang, Qin Institute of quantum information and technology Nanjing University of Posts and Telecommunications Nanjing210003 China "Broadband Wireless Communication and Senser Network Technology" Key Lab of Ministry of Education NUPT Nanjing210003 China "Telecommunication and Networks"National Engineering Research Center NUPT Nanjing210003 China

The measurement-device-independent quantum key distribution (MDI-QKD) possesses the highest security among all practical quantum key distribution protocols. However, existing multiintensity decoy-state methods may cause loopholes when modulating light intensities with practical devices. In this paper, we propose a passive decoy-state MDI-QKD protocol based on a novel structure of heralded single-photon sources. It does not need to modulate the light source into different intensities and thus can avoid leaking modulation information of decoy states to eavesdroppers, enhancing the security of practical MDI-QKD. Furthermore, by combining the passive decoy states and biased basis choices, our protocol can exhibit distinct advantages compared with state-of-the art MDI-QKD schemes even when the finite key-size effect is taken into account. Therefore, our present passive decoy-state MDI-QKD seems a promising candidate for practical implementation of quantum key distributions in the near future. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum cryptography

Proposal for low-power atom trapping on a GaN-on-sapphire chip

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Physical Review A 2022年第3期106卷 033104-033104页

作者： Aiping Liu Lei Xu Xin-Biao Xu Guang-Jie Chen Pengfei Zhang Guo-Yong Xiang Guang-Can Guo Qin Wang Chang-Ling Zou Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China State Key Laboratory of Quantum Optics and Quantum Optics Devices and Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

Hybrid photon-atom integrated circuits, which include photonic microcavities and trapped single neutral atoms in their evanescent field, have great potential for quantum information processing. In this platform, the atoms provide single-photon nonlinearity and long-lived memory, which are complementary to the excellent passive photonic devices in conventional quantum photonic circuits. In this work, we propose a stable platform for realizing hybrid photon-atom circuits based on an unsuspended photonic chip. By introducing high-order modes in the microring, a feasible evanescent-field trap potential well ∼0.26mK could be obtained by only 10-mW-level power in the cavity, compared with the 100-mW-level power required in the scheme based on fundamental modes. Based on our scheme, stable single-atom trapping with relatively low laser power is feasible for future studies on high-fidelity quantum gates, single-photon sources, and many-body quantum physics based on a controllable atom array in a microcavity.

关键词： Cooling & trapping Photonics Relativistic & quantum electrodynamic effects in atoms, molecules,& ions

Satellite-Terrestrial Spectrum Sensing Scheme Based on Cascaded FNN and FIS

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Satellite-Terrestrial Spectrum Sensing Scheme Based on Casca...

IEEE Globecom Workshops

作者： Yueyue Zhang Yunchi Shi Fei Shen Yihuan Pang Feng Yan Lianfeng Shen Shanghai Aerospace Electronic Technology Institute Shanghai China School of Information Science and Engineering Southeast University Jiangsu P. R. China Key Lab for Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences China

ISBN: (数字)9781728109602

ISBN: (纸本)9781728109619

Due to the frequency reuse in 5G enhanced satellite communications, advanced spectrum management would be acquired to improve the spectrum efficiency, with the interference mitigation caused by the frequency conflict in the manner of spectral sharing. To this end, cognitive radio (CR) has brought into the widespread attention, which aims at detection of spectrum holes by using the information collected from the secondary users (SUs). Specifically, considering the characteristics of satellite channels, the detection of spectrum holes would be more difficult in high dynamic situation. In this paper, we propose an efficient spectrum sensing scheme by taking advantage of the cooperation of satellites and base stations. Firstly, each base station (BS) receives the sensing information collected by its associated SUs. Then, a channel estimation algorithm based on fuzzy neutral network (FNN) is designed with the real-time sampling and historical data stored at BS. After that, the optimal probability of detection can be determined using fuzzy inference system (FIS) with the available sensing set. Additionally, the cooperative spectrum sensing results would be uploaded to the satellites, providing information for the further frequency allocation at the satellites' side. Finally, simulation results reveal the performance gain of the proposed algorithm in terms of the detection probability of spectrum hole.

关键词： sensors Satellite broadcasting Satellites Fuzzy neural networks Channel estimation 5G mobile communication

Quantum-enhanced interferometry with asymmetric beam splitters

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arXiv 2020年

作者： Zhong, Wei Wang, Fan Zhou, Lan Xu, Peng Sheng, Yu-Bo Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing210003 China National Laboratory of Solid State Microstructures Nanjing University Nanjing210093 China School of Science Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China

In this paper, we investigate the phase sensitivities in two-path optical interferometry with asymmetric beam splitters. Here, we present the optimal conditions for the transmission ratio and the phase of the beam splitter to gain the highest sensitivities for a general class of non-classical states with parity symmetry. Additionally, we address the controversial question of whether the scheme with a combination of coherent state and photon-added or photon-subtracted squeezed vacuum state is better or worse than the most celebrated one using a combination of coherent state and squeezed vacuum state. Copyright © 2020, The Authors. All rights reserved.

关键词： Fisher information matrix