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Joint modulation format identification and OSNR monitoring based on Stokes vector distribution features for digital coherent optical receivers

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Chinese Optics Letters 2024年第5期22卷 22-28页

作者：蒲正宇蒋林闫连山易安林何海军潘炜罗斌 Center for information Photonics&communications School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 611756China

For joint modulation format identification(MFI)and optical signal-to-noise ratio(OSNR)monitoring,a simple and intelligent optical communication performance monitoring method is proposed,and the feasibility is demonstrated by digital coherent optical communication *** experiment results show that for all modulation formats,including 28 GBaud polarization division multiplexing(PDM)QPSK/8-QAM/16-QAM/64-QAM,100%MFI accuracies are achieved even at OSNR values lower than the corresponding theoretical 20%forward error correction limit,as well as the high accuracies for OSNR ***,the proposed scheme has a reasonable monitoring level when chromatic dispersion and fiber nonlinear effects are varied.

关键词： coherent communication optical performance monitoring deep neural network

Carbon efficiency modeling and optimization of solar-powered cellular networks

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Science China(information Sciences) 2024年第5期67卷 228-243页

作者： Yuxi ZHAO Xiaohu GE Wen YAN Tao HAN Yi ZHONG school of Electronic information and communications Huazhong University of Science and Technology Huawei technology Co. Ltd.

As wireless communication traffic experiences rapid growth, the carbon emissions caused by the communication industry are also on the rise. To achieve “carbon neutrality”, researchers are considering the use of renewable energy sources to power cellular networks, thereby reducing carbon emissions. However, a challenge arises when using renewable energy, specifically owing to the unpredictable nature of both the energy consumption of the cellular network and the power generation from renewable sources. This inconsistency results in low renewable energy utilization and reduced carbon efficiency. Herein, we construct a carbon efficiency model of solar-powered cellular networks using practical data from solar radiation. We propose a mechanism that alternately optimizes the performance of the renewable energy network and the cellular network. This approach is based on convex optimization theory and the Dinkelback algorithm, and it leads to the design of a carbon efficiency optimization algorithm. This algorithm aims to improve the carbon efficiency of cellular networks and reduce their carbon emissions. Simulation results demonstrate that our optimization scheme yields a maximum improvement of 2.56 × 108bps/g in the carbon efficiency of the cellular network as compared to conventional power allocation schemes such as the traditional water filling method and heuristic energy sharing and charge/discharge algorithms.

关键词： cellular networks renewable energy carbon efficiency convex optimization theory dinkelbach

Channel modeling for MI-based wireless underground sensor networks with conductive objects

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Science China(information Sciences) 2024年第7期67卷 333-334页

作者： Shuhan DENG Guanghua LIU Ziwei CHEN Huaijin ZHANG Tao JIANG Research Center of 6G Mobile communications School of Cyber Science and EngineeringHuazhong University of Science and Technology school of Electronic information and communications Huazhong University of Science and Technology

Wireless underground sensor networks (WUSNs) are an emerging research field with promising applications. However, WUSNs links suffer from significant attenuation as the propagation of the signal needs to pass through soil, rock,and water. Magnetic induction (MI)-based transmission is proposed to overcome these issues as MI signal can penetrate most substances similarly without experiencing high path loss, which ensures the robustness of WUSNs links [1].

关键词： Wireless sensor networks

A new centrality measure based on neighbor loop structure for network dismantling

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Digital communications and Networks 2024年第2期10卷 472-480页

作者： Qingxia Liu Bang Wang Jiming Qi Xianjun Deng school of Electronic information and communications Huazhong University of Science and TechnologyWuhan430074China school of Cyber Science and Engineering Huazhong University of Science and TechnologyWuhan430074China

Nearly all real-world networks are complex networks and usually are in danger of ***,it is crucial to exploit and understand the mechanisms of network attacks and provide better protection for network *** dismantling aims to find the smallest set of nodes such that after their removal the network is broken into connected components of sub-extensive *** overcome the limitations and drawbacks of existing network dismantling methods,this paper focuses on network dismantling problem and proposes a neighbor-loop structure based centrality metric,NL,which achieves a balance between computational efficiency and evaluation *** addition,we design a novel method combining NL-based nodes-removing,greedy tree-breaking and ***,we compare five baseline methods with our algorithm on ten widely used real-world networks and three types of model networks including Erd€os-Renyi random networks,Watts-Strogatz smallworld networks and Barabasi-Albert scale-free networks with different network generation *** results demonstrate that our proposed method outperforms most peer methods by obtaining a minimal set of targeted attack ***,the insights gained from this study may be of assistance to future practical research into real-world networks.

关键词： Complex networks Network dismantling Centrality measure

Design and Implementation of a Time Synchronization Method for UOWC Networks

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Journal of communications and information Networks 2024年第1期9卷 56-63页

作者： Weijie Liu Jingyi Zhang Nuo Huang Zhengyuan Xu CAS Key Laboratory of Wireless-Optical communications School of Information Science and TechnologyUniversity of Science and Technology of ChinaHefei 230027China

Underwater optical wireless communication (UOWC) technology facilitates high-speed data transmission among multiple nodes in underwater networks. Nevertheless, the absence of a common clock poses a challenge to achieving systematic and reliable access for multiple nodes within these networks. This paper presents a time synchronization method for UOWC networks to ensure the successful execution of the media access control (MAC) protocol. In this method, the node obtains timestamps by exchanging messages with the optical access point (OAP). Subsequently, the node calculates the clock drift relative to the OAP and the propagation time,ensuring that transmitted data packets can arrive approximately at the time specified by the OAP. To validate the effect of the proposed method, an experimental UOWC prototype, including the OAP and nodes, is implemented using field programmable gate array (FPGA). The experimental results demonstrate that the maximum difference between the actual arrival times of two data packets that are expected to reach the OAP simultaneously according to the MAC protocol meets the requirements of the quasi-synchronous code division multiple access (QS-CDMA) system, thereby substantiating the effectiveness of this synchronization method.

关键词： UOWC time synchronization MAC FPGA QS-CDMA

Power-Domain Collision-Tolerant Random Access Method with Auxiliary Beam for Satellite Internet of Things:A New Solution

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China communications 2024年第8期21卷 236-248页

作者： Xu Yuanyuan Liu Ziwei Bian Dongming Zhang Gengxin school of communications and information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Institute of communications Engineering PLA University of Science and TechnologyNanjing 210007China

There are numerous terminals in the satellite Internet of Things(IoT).To save cost and reduce power consumption,the system needs terminals to catch the characteristics of low power consumption and light *** regular random access(RA)protocols may generate large amounts of collisions,which degrade the system throughout *** near-far effect and power control technologies are not applicable in capture effect to obtain power difference,resulting in the collisions that cannot be *** fact,the optimal design at the receiving end can also realize the condition of packet power domain separation,but there are few relevant *** this paper,an auxiliary beamforming scheme is proposed for power domain signal *** adds an auxiliary reception beam based on the conventional beam,utilizing the correlation of packets in time-frequency domain between the main and auxiliary beam to complete signal *** roll-off belt of auxiliary beam is used to create the carrier-to-noise ratio(CNR)*** paper uses the genetic algorithm to optimize the auxiliary beam *** results show that the proposed scheme outperforms slotted ALOHA(SA)in terms of system throughput per-formance and without bringing terminals additional control burden.

关键词： beamforming non-orthogonal multiple access random access satellite Internet of Things

Covert LEO Satellite Communication Aided by Generative Adversarial Network Based Cooperative UAV Jamming

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China communications 2024年第9期21卷 27-39页

作者： Shi Jia Li Xiaomeng Liao Xiaomin Tie Zhuangzhuang Hu Junfan school of Communication Engineering Xidian UniversityXi’an 710071China school of information and communications National University of Defense TechnologyWuhan 410073China

In this paper,we study the covert performance of the downlink low earth orbit(LEO)satellite communication,where the unmanned aerial vehicle(UAV)is employed as a cooperative *** maximize the covert rate of the LEO satellite transmission,a multi-objective problem is formulated to jointly optimize the UAV’s jamming power and *** practical consideration,we assume that the UAV can only have partial environmental information,and can’t know the detection threshold and exact location of the eavesdropper on the *** solve the multiobjective problem,we propose the data-driven generative adversarial network(DD-GAN)based method to optimize the power and trajectory of the UAV,in which the sample data is collected by using genetic algorithm(GA).Simulation results show that the jamming solution of UAV generated by DD-GAN can achieve an effective trade-off between covert rate and probability of detection errors when only limited prior information is obtained.

关键词： covert communication generative adversarial network LEO satellite UAV jammer

Actor-Critic-Based UAV-Assisted Data Collection in the Wireless Sensor Network

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China communications 2024年第4期21卷 163-177页

作者： Huang Xiaoge Wang Lingzhi He Yong Chen Qianbin school of communications and information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible ***,WSN data collection encounters challenges in scenarios lacking communication *** aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high *** this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the ***,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial *** ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the *** aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for ***,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of ***,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with ***,simulation results verify the effectiveness of the proposed algorithms.

关键词： actor critic data collection deep reinforcement learning unmanned aerial vehicle wireless sensor network

Channel Estimation for Reconfigurable Intelligent Surface Aided Multiuser Millimeter-Wave/THz Systems

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China communications 2024年第3期21卷 91-103页

作者： Chu Hongyun Pan Xue Li Baijiang school of communications and information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

It is assumed that reconfigurable intelligent surface(RIS)is a key technology to enable the potential of mmWave *** passivity of the RIS makes channel estimation difficult because the channel can only be measured at the transceiver and not at the *** this paper,we propose a novel separate channel estimator via exploiting the cascaded sparsity in the continuously valued angular domain of the cascaded channel for the RIS-enabled millimeter-wave/Tera-Hz systems,i.e.,the two-stage estimation method where the cascaded channel is separated into the base station(BS)-RIS and the RIS-user(UE)***,we first reveal the cascaded sparsity,i.e.,the sparsity exists in the hybrid angular domains of BS-RIS and the RIS-UEs separated channels,to construct the specific sparsity structure for RIS enabled multi-user ***,we formulate the channel estimation problem using atomic norm minimization(ANM)to enhance the proposed sparsity structure in the continuous angular domains,where a low-complexity channel estimator via Alternating Direction Method of Multipliers(ADMM)is *** findings demonstrate that the proposed channel estimator outperforms the current state-of-the-arts in terms of performance.

关键词： atomic norm minimization cascaded channel estimation convex optimization mmWave/THz reconfigurable intelligent surface(RIS) sparsity