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China communications 2024年第2期21卷 227-244页

作者： Meng Meng Bo Hu Shanzhi Chen Jianyin Zhang State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Wireless mobile communication China Academy of Telecommunication TechnologyBeijing 100191China Research Institute of China mobile Beijing 100053China

Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system *** optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method ***, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput.

关键词： convex optimization intelligent reflecting surface LEO satellite communication OFDM

A Parallel Discrete Event Simulation Engine for the Low-Earth-Orbit satellite Constellation Networks

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China communications 2024年第8期21卷 264-275页

作者： Su Hailong Liu Yaoqi Zhou Yiqing Shi Jinglin Li Hongguang Qian Manli Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Lab of Processors Institute of Computing TechnologyCASBeijing 100190China Zhongke Nanjing mobile communication&Computing Innovation Institute Nanjing 211135China Beijing Sylincom Technology Co. Beijing 100190China

Low-Earth-Orbit satellite constellation networks(LEO-SCN)can provide low-cost,largescale,flexible coverage wireless communication *** dynamics and large topological sizes characterize *** development and application testing of LEO-SCN are challenging to carry out in a natural *** platforms are a more effective means of technology *** available simulators have a single function and limited simulation *** needs to be a simulator for full-featured *** this paper,we apply the parallel discrete-event simulation technique to the simulation of LEO-SCN to support large-scale complex system simulation at the packet *** solve the problem that single-process programs cannot cope with complex simulations containing numerous entities,we propose a parallel mechanism and algorithms LP-NM and LP-YAWNS for *** the experiment,we use ns-3 to verify the acceleration ratio and efficiency of the above *** results show that our proposed mechanism can provide parallel simulation engine support for the LEO-SCN.

关键词： constellation low earth orbit satellite ns-3 null-message parallel discrete-event simulation

A Self-Attention Based Dynamic Resource Management for satellite-Terrestrial Networks

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China communications 2024年第4期21卷 136-150页

作者： Lin Tianhao Luo Zhiyong School of Electronics and communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Peng Cheng Laboratory Shenzhen 518107China

The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power support,which is an important development direction of future *** this paper,we take into account a multi-scenario network model under the coverage of low earth orbit(LEO)satellite,which can provide computing resources to users in faraway areas to improve task processing ***,LEO satellites experience limitations in computing and communication resources and the channels are time-varying and complex,which makes the extraction of state information a daunting ***,we explore the dynamic resource management issue pertaining to joint computing,communication resource allocation and power control for multi-access edge computing(MEC).In order to tackle this formidable issue,we undertake the task of transforming the issue into a Markov decision process(MDP)problem and propose the self-attention based dynamic resource management(SABDRM)algorithm,which effectively extracts state information features to enhance the training *** results show that the proposed algorithm is capable of effectively reducing the long-term average delay and energy consumption of the tasks.

关键词： mobile edge computing resource management satellite-terrestrial networks self-attention

Semantic-aware coordinated transmission in cohesive clustered satellites: utility of information perspective

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Science China(Information Sciences) 2024年第09期67卷 338-339页

作者： Liang XU Jian JIAO Shiyao JIANG Ye WANG Qinyu ZHANG Guangdong Provincial Key Laboratory of Aerospace communication and Networking Technology Harbin Institute of Technology (Shenzhen) Pengcheng Laboratory

The cohesive clustered satellite(CCS) concept integrates diverse satellite payloads from different orbits, such as communication, remote sensing, and navigation satellites, into mobile, geometrically stable clusters for efficient collaborative networking [1]. By aggregating, reconstructing, and orchestrating heterogeneous satellite resources, such as computation, communication, and storage [2], the CCS enables resource ultra-sharing and provides information-centric and goal-oriented intelligent on-demand services [3] for a range of emerging Earth observation and deep space exploration missions [4].

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同方期刊数据库

Stochastic Dynamic Modeling of Rain Attenuation: A Survey

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China communications 2018年第3期15卷 220-235页

作者： Zhicheng Qu Gengxin Zhang Haotong Cao Jidong Xie College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications satellite & mobile communication section Nanjing University of Posts and Telecommunications National Local Joint Engineering Research Center for communication and network technology Nanjing University of Posts and Telecommunications Key Laboratory of Broadband Wireless communication and Sensor Network Technique of Ministry of Education Nanjing University of Posts and Telecommunications

satellite communication systems(SCS) operating on frequency bands above 10 GHz are sensitive to atmosphere physical phenomena, especially rain attenuation. To evaluate impairments in satellite performance, stochastic dynamic modeling(SDM) is considered as an effective way to predict real-time satellite channel fading caused by rain. This article carries out a survey of SDM using stochastic differential equations(SDEs) currently in the literature. Special attention is given to the different input characteristics of each model to satisfy specific local conditions. Future research directions in SDM are also suggested in this paper.

关键词： stochastic dynamic modeling rainattenuation time-series synthesizer satellitecommunication satellite link stochastic dif-ferential equations

Energy-Efficient Traffic Offloading for RSMA-Based Hybrid satellite Terrestrial Networks with Deep Reinforcement Learning

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China communications 2024年第2期21卷 49-58页

作者： Qingmiao Zhang Lidong Zhu Yanyan Chen Shan Jiang National Key Laboratory of Science and Technology on communications University of Electronic Science and Technology of ChinaChengdu 611731China The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province Xiamen Institute of TechnologyXiamen 361021China China mobile(Jiangxi)communications Group Co. LtdYichun 336000China

As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can provide higher efficiency with limited spectrum resources. In this paper, combining spectrum splitting with rate splitting, we propose to allocate resources with traffic offloading in hybrid satellite terrestrial networks. A novel deep reinforcement learning method is adopted to solve this challenging non-convex problem. However, the neverending learning process could prohibit its practical implementation. Therefore, we introduce the switch mechanism to avoid unnecessary learning. Additionally, the QoS constraint in the scheme can rule out unsuccessful transmission. The simulation results validates the energy efficiency performance and the convergence speed of the proposed algorithm.

关键词： deep reinforcement learning energy efficiency hybrid satellite terrestrial networks rate splitting multiple access traffic offloading

satellite Constellation Design with Multi-Objective Genetic Algorithm for Regional Terrestrial satellite Network

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China communications 2018年第8期15卷 1-10页

作者： Cuiqin Dai Guimin Zheng Qianbin Chen Chongqing Key Lab of mobile communication Technology Chongqing University of Posts and Telecommunications

Constellations design for regional terrestrial-satellite network can strengthen the coverage for incomplete terrestrial cellular network. In this paper, a regional satellite constellation design scheme with multiple feature points and multiple optimization indicators is proposed by comprehensively considering multi-objective optimization and genetic algorithm, and "the Belt and Road" model is presented in the way of dividing over 70 nations into three regular target areas. Following this, we formulate the optimization model and devise a multi-objective genetic algorithm suited for the regional area with the coverage rate under simulating, computing and determining. Meanwhile, the total number of satellites in the constellation is reduced by calculating the ratio of actual coverage of a single-orbit constellation and the area of targets. Moreover, the constellations' performances of the proposed scheme are investigated with the connection of C++ and satellite Tool Kit(STK). Simulation results show that the designed satellite constellations can achieve a good coverage of the target areas.

关键词： regional terrestrial-satellite net-work constellation design multi-objective optimization genetic algorithm coverage performance

Reputation-Based Cooperative Spectrum Sensing Algorithm for mobile Cognitive Radio Networks

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China communications 2017年第1期14卷 124-134页

作者： Xinyu Wang Min Jia Qing Guo Xuemai Gu Guangyu Zhang communication Research Center Harbin Institute of Technology Harbin 150080 China Research Center of satellite Harbin Institute of Technology Harbin 150080 China

Identifying malicious users accurately in cognitive radio networks(CRNs) is the guarantee for excellent detection performance. However, existing algorithms fail to take the mobility of secondary users into consideration. If applied directly in mobile CRNs, those conventional algorithms would overly punish reliable users at extremely bad or good locations, leading to an obvious decrease in detection performance. To overcome this problem, we divide the whole area of interest into several cells to consider the location diversity of the network. Each user's reputation score is updated after each sensing slot and is used for identifying whether it is malicious or not. If so, it would be removed away. And then our algorithm assigns users in cells with better channel conditions, i.e. larger signal-to-noise ratios(SNRs), with larger weighting coefficients, without requiring the prior information of SNR. Detailed analysis about the validity of our algorithm is presented. The simulation results show that in a CRN with 60 mobile secondary users, among which, 18 are malicious, our solution has an improvement of detection probability by 0.97-d B and 3.57-d B when false alarm probability is 0.1, compared with a conventional trust-value-based algorithm and a trusted collaborative spectrum sensing for mobile CRNs, respectively.

关键词： cognitive radio cooperative spectrum sensing mobility malicious users reputation score

Research on User Terminals’ Acquisition Sensitivity Based On P2P Aiding

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Research on User Terminals’ Acquisition Sensitivity Based O...

Heuristic Computing Methods for Contact Plan Design in the Spatial-Node-Based Internet of Everything

第五届中国卫星导航学术年会

作者： Dai Weiheng Tian Shiwei Sun Lipeng Chang Jiang College of communication Engineering of PLA University of science and technology Taiyuan satellite Launch Center

ISBN: (纸本)9783642547362

With development of short range communication technology,P2P（Peer to Peer） networks are pervasive, and the nav-com user terminals become popular. The application of P2P networks provide the new method to improve positioning performances of user terminals. Compared to conventional A-GNSS augmentation,P2P aiding is completed by user terminals each other, which don’t depend on preinstalled communication infrastructures （ e.g., mobile communication base stations ） . In P2P networks ,aiding sources are closer to aided users than conventional base stations aiding. The advantage can provide more accurate and reliable augmentation information, so the user terminals can get better augmentation performances. Now there are some groups research P2P aiding,but their topic is the mean acquisition times. But the acquisition sensitivity is very important metric for both military users and civil *** paper researches performance of acquisition sensitivity in P2P networks. The aiding peer can receive both GNSS signals and the communication signals of aided peer,. According to the real-time measurements of carrier phase and frequency offset , the aided peer can get real-time local frequency offset values. Based on these values, the peer can extend coherent integration time and improve the acquisition sensitivity. Simulation show that the aided user can complete coherent integration of several seconds, and the non-aided user only do for hundreds of milliseconds. The aided terminal can reliably work in low signal-noise ration, 1 even in 10dB Hz condition. The requirement of communication rate is less than 1kps.

关键词： P2P aiding Acquisition sensitivity Coherent integration time

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China communications 2019年第3期16卷 53-68页

作者： Cuiqin Dai Qingyang Song School of Computer Science and Engineering Northeastern University Chongqing Key Lab of mobile communication Technology Chongqing University of Posts and Telecommunications School of communication and Information Engineering Chongqing University of Posts and Telecommunications

To satisfy the increasing demands of high-speed transmission, high-efficiency computing, and real-time communications in the high-dynamic and heterogeneous networks, the Contact Plan Design(CPD) has attracted continuous attention in recent years, especially for the spatial-node-based Internet of Everything(IoE). In this paper, we study the NP-hardness of contact scheduling and the attenuation of atmospheric precipitation in the spatial-node-based IoE. Two heuristic computing methods for contact plan design are proposed by comprehensively considering the time-varying topology, the intermittent connectivity, and the adaptive transmission in different weather conditions, which are named Contact Plan Design-Particle Swarm Optimization(CPD-PSO) and Contact Plan Design-Greedy algorithm with the Minimum Delivery Time(CPD-GMDT) separately. For the population-based algorithm, CPD-PSO not only solves the CPD problem with a limited-resource condition, but also dynamically adjusts the search scope to ensure the continuous searching capability of the algorithm. For the CPD-GMDT that makes CP decisions based on the current state, the algorithm uses the idea of greedy algorithm to schedule satellite-Platform Links(SPLs) and Inter satellite Links(ISLs) respectively using the strategies of optimal matching and load balancing. The simulation results show that the proposed CPD-PSO outperforms Contact Plan Design-Genetic Algorithm(CPD-GA) in terms of fitness and delivery time, and CPD-GMDT presents better overall delay than Fair Contact Plan(FCP).

关键词： Internet of Everything heuristic computing contact plan design particle swarm optimization greedy algorithms