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Resource Optimization for LEO Constellation networks: A Multi-satellite Cooperative Coverage Design

IEEE Transactions on Communications 2025年

作者： Ma, Xu Zhang, Haijun Song, Wei Lu, Yang Wu, Yuan Leung, Victor C.M University of Science and Technology Beijing Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services Beijing100083 China China Electric Power Research Institute Co. Ltd Beijing102209 China University of Macau State Key Laboratory of Internet of Things for Smart City Macau China University of Macau Department of Computer and Information Science Macau China Shenzhen University Department of Computer Science and Software Engineering Shenzhen518061 China

With its low latency, high throughput, good deployment flexibility, and cost-effectiveness, the low earth orbit (LEO) constellation is regarded as a promising technology for seamless coverage. Unlike geosynchronous orbiting (GSO) satellites, the highly dynamic evolution of LEO constellation topology poses a significant challenge to the traditional scheme of allocating wireless resources. This paper proposes a multisatellite cooperative coverage resource allocation for the LEO constellation. A multi-objective optimization problem focusing on throughput and coverage time is proposed for the overall service quality of the LEO constellation. To solve the complex coupling between multi-domain resources, the optimization problem is decomposed into three key subproblems, which are the beam placement problem, the joint beam association with power allocation problem, and the beam hopping time slot allocation problem. For each subproblem, an adaptive algorithm is proposed that effectively exploits the payload of LEO satellites to ensure the coverage performance of the constellation network. Simulation results demonstrate that the proposed coverage scheme enables fast convergence, enhances network throughput utility, and guarantees the stability and fairness of the communication services. © 1972-2012 IEEE.

关键词： Multiobjective optimization

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Modeling and Performance Analysis of IoT-Over-LEO Satellite Systems Under Realistic Operational Constraints: A Stochastic Geometry Approach

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IEEE Internet of Things Journal 2025年

作者： Dong, Wen-Yu Yang, Shaoshi Zhang, Ping Chen, Sheng Beijing University of Posts and Telecommunications School of Information and Communication Engineering Beijing 100876 China Ministry of Education Key Laboratory of Universal Wireless Communications Beijing 100876 China Ministry of Education Key Laboratory of Mathematics and Information Networks Beijing 100876 China State Key Laboratory of Networking and Switching Technology Beijing 100876 China University of Southampton School of Electronics and Computer Science Southampton SO17 1BJ United Kingdom

The growing demand for reliable and extensive connectivity has made low Earth orbit (LEO) satellites aided Internet of Things (IoT) systems a critical area of research. However, current theoretical studies on IoT-over-LEO satellite systems often rely on unrealistic assumptions, such as infinite terrestrial areas and omnidirectional satellite coverage, leaving significant gaps in theoretical analysis for more realistic operational constraints. These constraints involve finite terrestrial area, limited satellite coverage, Earth curvature effect, integral uplink and downlink analysis, and link-dependent interference. To address these gaps, this paper proposes a novel stochastic geometry based model to rigorously analyze the performance of IoT-over-LEO satellite systems. By adopting a binomial point process (BPP) instead of the conventional Poisson point process (PPP), our model accurately characterizes the geographical distribution of a fixed number of IoT devices in a finite terrestrial region. This modeling framework enables the derivation of distance distribution functions for both the links from the terrestrial IoT devices to the satellites (T-S) and from the satellites to the Earth station (S-ES), while also accounting for limited satellite coverage and Earth curvature effects. To realistically represent channel conditions, the Nakagami fading model is employed for the T-S links to characterize diverse small-scale fading environments, while the shadowed-Rician fading model is used for the S-ES links to capture the combined effects of shadowing and dominant line-of-sight paths. Furthermore, the analysis incorporates uplink and downlink interference, ensuring a comprehensive evaluation of system performance. The accuracy and effectiveness of our theoretical framework are validated through extensive Monte Carlo simulations. These results provide insights into key performance metrics, such as coverage probability and average ergodic rate, for both individual links and

关键词： coverage probability IoT-over-LEO satellites Nakagami fading shadowed-Rician fading stochastic geometry

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A coupled gradient network approach for static and temporal mixed-integer optimization

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IEEE TRANSACTIONS ON NEURAL networks 1996年第3期7卷 578-593页

作者： Watta, PB Hassoun, MH Computation and Neural Networks Laboratory Department of Electrical and Computer Engineering Wayne State University Detroit MI USA

The purpose of this work is to utilize the ideas of artificial neural networks to propose new solution methods for a class of constrained mixed-integer optimization problems, These new solution methods are more suitable to parallel implementation than the usual sequential methods of mathematical programming, Another attractive feature of the proposed approach is that some mechanisms of global search may be easily incorporated into the computation, producing results which are more globally optimal, To formulate the method of solution proposed in this work, a penalty function approach is used to define a coupled gradient-type network with an appropriate architecture. energy function, and dynamics such that high quality solutions may be obtained upon convergence of the dynamics, Finally, it is shown how the coupled gradient net mag be extended to handle temporal mixed-integer optimization problems, and simulations are presented which demonstrate the effectiveness of the approach.

关键词： Constraint optimization Biological neural networks Artificial neural networks Distributed computing Biology computing computer networks Lagrangian functions Mathematical programming computer architecture Computational modeling

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Quorum-based channel hopping scheme for cognitive radio networks

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Science China(Information Sciences) 2013年第4期56卷 219-224页

作者： LI XiaoYan ZHANG HaiLin HU Fei SHI Chao State Key Laboratory of Integrated Services Networks Xidian University Department of Electrical and Computer Engineering University of Alabama

In cognitive radio networks,secondary users(SUs) tune themselves to the available spectrum to meet each other and establish communication links to transmit *** is the rendezvous *** hopping(CH) schemes have been proposed to establish pairwise *** this paper,we present a distributed CH scheme based on the quorum system to make SUs rendezvous on their common available channels within a bounded *** scheme can guarantee rendezvous even when SUs sense different sets of available *** results show that the proposed CH scheme outperforms existing schemes in terms of average time-to-rendezvous and success rate.

关键词： cognitive radio channel hopping scheme rendezvous quorum system MAC

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Byzantine-Resilient Over-the-Air Federated Learning under Zero-Trust Architecture

arXiv

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arXiv 2025年

作者： Yao, Jiacheng Shi, Wei Xu, Wei Yang, Zhaohui Swindlehurst, A. Lee Niyato, Dusit The National Mobile Communications Research Laboratory Southeast University Nanjing210096 China The Purple Mountain Laboratories Nanjing211111 China The Research Institute of Intelligent Networks Zhejiang Lab Hangzhou311121 China The College of Information Science and Electronic Engineering Zhejiang University Zhejiang Hangzhou310027 China The Center for Pervasive Communications and Computing Henry Samueli School of Engineering University of California at Irvine IrvineCA92697 United States The School of Computer Science and Engineering Nanyang Technological University Singapore308232 Singapore

Over-the-air computation (AirComp) has emerged as an essential approach for enabling communication-efficient federated learning (FL) over wireless networks. Nonetheless, the inherent analog transmission mechanism in AirComp-based FL (AirFL) intensifies challenges posed by potential Byzantine attacks. In this paper, we propose a novel Byzantine-robust FL paradigm for over-the-air transmissions, referred to as federated learning with secure adaptive clustering (FedSAC). FedSAC aims to protect a portion of the devices from attacks through zero trust architecture (ZTA) based Byzantine identification and adaptive device clustering. By conducting a one-step convergence analysis, we theoretically characterize the convergence behavior with different device clustering mechanisms and uneven aggregation weighting factors for each device. Building upon our analytical results, we formulate a joint optimization problem for the clustering and weighting factors in each communication round. To facilitate the targeted optimization, we propose a dynamic Byzantine identification method using historical reputation based on ZTA. Furthermore, we introduce a sequential clustering method, transforming the joint optimization into a weighting optimization problem without sacrificing the optimality. To optimize the weighting, we capitalize on the penalty convex-concave procedure (P-CCP) to obtain a stationary solution. Numerical results substantiate the superiority of the proposed FedSAC over existing methods in terms of both test accuracy and convergence rate. Copyright © 2025, The Authors. All rights reserved.

关键词： Federated learning

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An EFSM-based multimedia synchronization model and the authoring system

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1996年第1期14卷 138-152页

作者： Huang, CM Lo, CM Laboratory of Computer Networks and Multimedia Systems Institute of Information Engineering National Cheng Kung University Tainan Taiwan

Multimedia synchronization is one of the key issues to be resolved in order to have smooth multimedia presentations. The demand of bringing multimedia information systems into distributed environments makes multimedia synchronization more difficult. In this paper, we apply extended finite state machines (EFSM) to formally specify multimedia synchronization among multiple media streams. Using the EFSM model, the intra-medium synchronization is handled by an actor, which is formally represented as an EFSM, The inter-media synchronization is handled by a synchronizer, which is also represented as an EFSM, Both centralized and distributed synchronization cases can be specified. Synchronizer and Actors achieve the corresponding multimedia presentations cooperatively. We also propose some policies to rectify the random delays caused by networks in the distributed presentation case. These policies, which can be formally specified in the corresponding EFSMs, are classified as intra-stream and inter-stream synchronization policies. Using the EFSM-based model, an authoring system and an associated experimental execution environment has been developed on SUN SPARC workstations.

关键词： multimedia synchronization extended finite state machine (EFSM) protocols

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Cooperative Secrecy to Resist Authentication Error in Two-Hop Wireless networks

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Chinese Journal of Electronics 2016年第4期25卷 746-752页

作者： SHEN Yulong PEI Qingqi MA Jianfeng School of Computer Science and Technology Xidian University The State Key Laboratory of Integrated Services Networks School of Telecommunications Engineering Xidian University

The authentication error in two-hop wireless networks is considered without knowledge of eavesdropper channels and *** wireless informationtheoretic security has attracted considerable attention recently.A prerequisite for available works is the precise distinction between legitimate nodes and *** it is unrealistic in the wireless *** is always existing in the node authentication *** of our knowledge,there are no works focus on solving this problem in the information-theoretic *** paper presents a eavesdropper model with authentication error and two eavesdropping ***,the number of eavesdroppers can be tolerated is analyzed while the desired secrecy is achieved with high probability in the limit of a large number of relay ***,we draw two conclusions for authentication error:1) The impersonate nodes are chosen as relay is the dominant factor of the transmitted message leakage,and the impersonation attack does seriously decrease the number of eavesdroppers can be tolerated.2) The error authentication to legitimate nodes is almost no effect on the number of eavesdroppers can be tolerated.

关键词： Wireless networks Information-theoretic security Cooperative secrecy Authentication error

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引用

Frontiers of Information Technology & Electronic engineering 2017年第6期18卷 796-807页

作者： Zhen-hua YUAN Chen CHEN Xiang CHENG Guo-cheng LV Liu-qing YANG Ye JIN State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Department of Electrical & Computer Engineering Colorado State University

This article is focused on secure relay beamformer design with a correlated channel model in the relay-eavesdropper network. In this network, a single-antenna source-destination pair transmits secure information with the help of an amplify-and-forward (AF) relay equipped with multiple antennas, and the legitimate and eavesdropping channels are correlated. The relay cannot obtain the instantaneous channel state information (CSI) of the eavesdropper, and has only the knowledge of correlation information between the legitimate and eavesdropping channels. Depending on this information, we derive the conditional distribution of the eavesdropping channel. Two beamformers at the relay are studied for the approximate ergodic secrecy rate:(1) the generalized match-andforward (GMF) beamformer to maximize the legitimate channel rate, and (2) the general-rank beamformer (GRBF).In addition, one lower-bound-maximizing (LBM) beamformer at the relay is discussed for maximizing the lower bound of the ergodic secrecy rate. We find that the GMF beamformer is the optimal rank-one beamformer, that the GRBF is the iteratively optimal beamformer, and that the performance of the LBM beamformer for the ergodic secrecy rate gets close to that of the GRBF for the approximate secrecy rate. It can also be observed that when the relay has lower power or the channel gain of the second hop is low, the performance of the GMF beamformer surpasses that of the GRBF. Numerical results are presented to illustrate the beamformers' performance.

关键词： Physical layer security Relay beamforming Correlated channels Ergodic secrecy rate

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Measuring Structural Quality of Object-Oriented Softwares via Bug Propagation Analysis on Weighted Software networks

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Journal of computer Science & Technology 2010年第6期25卷 1202-1213页

作者：潘伟丰李兵马于涛覃叶宜周晓燕 State Key Laboratory of Software Engineering Wuhan University School of Computer Wuhan University Complex Networks Research Center Wuhan University

The quality of a software system is partially determined by its structure（topological structure）,so the need to quantitatively analyze the quality of the structure has become *** this paper a novel metric called software quality of structure（SQoS） is presented for quantitatively measuring the structural quality of object-oriented（OO） softwares via bug propagation analysis on weighted software networks（WSNs）.First,the software systems are modeled as a WSN,weighted class dependency network（WCDN）,in which classes are nodes and the interaction between every pair of classes if any is a directed edge with a weight indicating the probability that a bug in one class will propagate to the *** we analyze the bug propagation process in the WCDN together with the bug proneness of each class,and based on this,a metric（SQoS） to measure the structural quality of OO softwares as a whole is *** approach is evaluated in two case studies on open source Java programs using different software structures（one employs design patterns and the other does not） for the same OO *** results of the case studies validate the effectiveness of the proposed *** approach is fully automated by a tool written in Java.

关键词： bug propagation design pattern object-oriented（OO） software software network structural quality

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A flow control scheme on ATM networks with max-min fairness

引用

computer COMMUNICATIONS 1999年第6期22卷 543-555页

作者： Lai, WK Tsai, JY High Speed Networks Laboratory Institute of Computer and Information Engineering National Sun Yat-Sen University Kaohsiung Taiwan

Asynchronous Transfer Mode does not guarantee Quality of Service for Available Bit Rate (ABR) service type during connection establishment. The remaining bandwidth for ABR traffics varies. Without adequate flow control, congestion can cause the degradation of network performance. In this article, we propose an Explicit Rate calculating Algorithm with Max-Min fairness (ERAMM) for rate-based flow control. From analysis and simulation results, we know the ERAMM has the advantages of fast convergence, low oscillations, little parameter sensitivity, and high link bandwidth utilization with less buffer requirements. (C) 1999 Elsevier Science B.V. All rights reserved.

关键词： asynchronous transfer mode available bit rate quality of service congestion rate-based flow control

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