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Hybrid event-and time-triggered control for double-integrator heterogeneous networks

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Science China(Information Sciences) 2019年第2期62卷 73-84页

作者： Gaopeng DUAN Feng XIAO Long WANG Center for Systems and Control College of Engineering Peking University Research Institute of Intelligent Control and Systems Harbin Institute of Technology

This paper investigates the state consensus for double-integrator networks under heterogeneous interaction topologies. For double-integrator networks, the setting of heterogeneous topologies means that position and velocity information flows are modeled by two different graphs. The corresponding protocol proposed in this paper is based on edge-event-triggered control. The events based on position information are irrelevant to velocity information and independent of the events based on velocity information. And for different edges, the corresponding events are activated independently of each other. Once an event occurs,the agents connected by the associated edge will sample their corresponding relative state information and update their corresponding controllers. Furthermore, under the presented event-triggering rules, the state consensus of double-integrator networks can be achieved by designing appropriate parameters. In addition,the proposed protocol with the event-triggering rules can effectively improve the system performance and avoid the occurrence of Zeno behaviors. Finally, a simulation example is worked out to verify the theoretical analysis.

关键词： consensus sampled-data control multi-agent systems edge-event-triggered control heterogeneous networks

Energy-efficient power allocation for NOMA heterogeneous networks with imperfect CSI

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The Journal of China Universities of Posts and Telecommunications 2022年第1期29卷 102-112页

作者： Song Xin Huang Xue Gao Yiming Qian Haijun School of Computer and Communication Engineering Northeastern University at QinhuangdaoQinhuangdao 066000China

In this paper,an optimal user power allocation scheme is proposed to maximize the energy efficiency for downlink non-orthogonal multiple access(NOMA)heterogeneous networks(HetNets).Considering channel estimation errors and inter-user interference under imperfect channel state information(CSI),the energy efficiency optimization problem is formulated,which is non-deterministic polynomial(NP)-hard and *** cope with this intractable problem,the optimization problem is converted into a convex problem and address it by the Lagrangian dual ***,it is difficult to obtain closed-form solutions since the variables are coupled with each ***,a Lagrangian and sub-gradient based algorithm is *** the inner layer loop,optimal powers are derived by the sub-gradient *** the outer layer loop,optimal Lagrangian dual variables are *** results show that the proposed algorithm can significantly improve energy efficiency compared with traditional power allocation algorithms.

关键词： heterogeneous networks non-orthogonal multiple access imperfect channel state information power allocation

Dynamic spreading behavior of homogeneous and heterogeneous networks

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Progress in Natural Science:Materials International 2007年第3期17卷 358-365页

作者： XIA Chengyi, LIU Zhongxin, CHEN Zengqiang and YUAN Zhuzhi ( Department of Automation, Nankai University, Tianjin 300071, China Department of Computer Science and Engineering, Tian-jin University of Technology, Tianjin 300191, China) Department of Automation Nankai University Tianjin 300071 China Department of Computer Science and Engineering Tianjin University of Technology Tianjin 300191 China

The detailed investigation of the dynamic epidemic spreading on homogeneous and heterogeneous networks was carried out. After the analysis of the basic epidemic models, the susceptible-infected-susceptible (SIS) model on homogenous and heterogeneous networks is established, and the dynamical evolution of the density of the infected individuals in these two different kinds of networks is analyzed theoretically. It indicates that heterogeneous networks are easier to propagate for the epidemics and the leading spreading behavior is dictated by the exponential increasing in the initial outbreaks. Large-scale simulations display that the infection is much faster on heterogeneous networks than that on homogeneous ones. It means that the network topology can have a significant effect on the epidemics taking place on complex networks. Some containment strategies of epidemic outbreaks are presented according to the theoretical analyses and numerical simulations.

关键词： complex networks dynamic epidemic spreading SIS model homogeneous networks heterogeneous networks containment strategies.

An enhanced framework for providing multimedia broadcast/multicast service over heterogeneous networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第1期15卷 63-80页

作者： Yi-han XU Chee-Onn CHOW Mau-Luen THAM Hiroshi ISHII Department of Electrical Engineering University of Malaya Professional Graduate School of Embedded Technology Tokai University

Multimedia broadcast multicast service(MBMS)with inherently low requirement for network resources has been proposed as a candidate solution for using such resources in a more efficient *** the other hand,the Next Generation Mobile Network(NGMN)combines multiple radio access technologies(RATs)to optimize overall network *** performance is becoming a vital indicator of the quality experience of mobile user equipment(UE).In contrast to the conventional vertical handover issue,the problem we are facing is how to seamlessly transmit broadcast/multicast sessions among heterogeneous *** this paper,we propose a new network entity,media independent broadcast multicast service center(MIBM-SC),to provide seamless handover for broadcast/multicast sessions over heterogeneous networks,by extensions and enhancements of MBMS and media independent information service(MIIS)***,a network selection scheme and a cell transmission mode selection scheme are proposed for selecting the best target network and best transmission *** schemes are based on a load-aware network capacity estimation *** results show that the proposed approach has the capability to provide MBMS over heterogeneous networks,with improved handover performance in terms of packet loss rate,throughput,handover delay,cell load,bandwidth usage,and the peak signal-to-noise ratio(PSNR).

关键词： IEEE 802.21 MIBM-SC MBMS MILS heterogeneous networks Network resource management

Energy efficiency enhancement in heterogeneous networks:a joint resource allocation approach

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The Journal of China Universities of Posts and Telecommunications 2015年第4期22卷 74-80页

作者： Sun Yujing Wang Yongbin Li Yi Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications

To support the drastic growth of wireless multimedia services and the requirements of ubiquitous access, numerous wireless infrastructures which consume enormous energy, such as macrocell, small cell, distributed antenna systems and wireless sensor networks, have been deployed. Under the background of environmental protection, improving the energy efficiency（EE） in wireless networks is becoming more and more important. In this paper, an EE enhancement scheme in heterogeneous networks（Het Nets） by using a joint resource allocation approach is proposed. The Het Nets consists of a mix of macrocell and small cells. Firstly, we model this strategic coexistence as a multi-agent system in which decentralized resource management inspired from Reinforcement Learning are devised. Secondly, a Q-learning based joint resource allocation algorithm is designed. Meanwhile, with the consideration of the time-varying channel characteristics, we take the long-term learning reward into account. At last, simulation results show that the proposed decentralized algorithm can approximate to centralized algorithm with low-complexity and obtain high spectral efficiency（SE） in the meantime.

关键词： heterogeneous networks energy efficiency reinforcement learning decentralized resource allocation joint resource allocation appr

Interference management via access control and mobility prediction in two-tier heterogeneous networks

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Journal of Central South University 2014年第8期21卷 3169-3177页

作者：肖竹陈杰王东李仁发易克初 College of Information Science and Engineering Hunan University State Key Laboratory of Integrated Service networks (Xidian University)

Abstract： Two-tier heterogeneous networks （HetNets）, where the current cellular networks, i.e., macrocells, are overlapped with a large number of randomly distributed femtocells, can potentially bring significant benefits to spectral utilization and system capacity. The interference management and access control for open and closed femtocells in two-tier HetNets were focused. The contributions consist of two parts. Firstly, in order to reduce the uplink interference caused by MUEs （macrocell user equipments） at closed femtocells, an incentive mechanism to implement interference mitigation was proposed. It encourages femtoeells that work with closed-subscriber-group （CSG） to allow the interfering MUEs access in but only via uplink, which can reduce the interference significantly and also benefit the marco-tier. The interference issue was then studied in open-subscriber-group （OSG） femtocells from the perspective of handover and mobility prediction. Inbound handover provides an alternative solution for open femtocells when interference turns up, while this accompanies with PCI （physical cell identity） confusion during inbound handover. To reduce the PCI confusion, a dynamic PCI allocation scheme was proposed, by which the high handin femtocells have the dedicated PCI while the others share the reuse PCIs. A Markov chain based mobility prediction algorithm was designed to decide whether the femtoeell status is with high handover requests. Numerical analysis reveals that the UL interference is managed well for the CSG femtocell and the PCI confusion issue is mitigated greatly in OSG femtocell compared to the conventional approaches.

关键词： femtocell macrocell interference management heterogeneous networks access control handover mobility prediction

Joint User Association and Fair Scheduling for Dual Connectivity heterogeneous networks

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China Communications 2023年第1期20卷 171-183页

作者： Haixia Cui Yongliang Du School of Electronics and Information Engineering South China Normal UniversityFoshan 528225China School of Physics and Telecommunication Engineering South China Normal UniversityGuangzhou 510006China

heterogeneous small cell network is one of the most effective solutions to overcome spectrum scarcity for the next generation of mobile *** connectivity(DC)can improve the throughput for each individual user by allowing concurrent access to two heterogeneous radio *** this paper,we propose a joint user association and fair scheduling algorithm(JUAFS)to deal with the resource allocation and load balancing issues for DC heterogeneous small cell *** different coverage sizes,numbers of users,and quality of experience characteristics of heterogeneous cells,we present a proportional fair scheduling for user association among cells and utilize interference graph to minimize the transmission conflict *** results show the performance improvement of the proposed algorithm in spectrum efficiency and fairness comparing to the existing schemes.

关键词： fair scheduling heterogeneous networks dual connectivity interference management

A noninteracting control strategy for the robust output synchronization of linear heterogeneous networks

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Control Theory and Technology 2014年第3期12卷 234-249页

作者： Saman KHODAVERDIAN Jürgen ADAMY Institute of Automatic Control and Mechatronics Control Methods and Robotics Lab Technische Universitt DarmstadtLandgraf-Georg-Str.464283 Darmstadt Germany

This paper deals with the problem of robust output synchronization for heterogeneous multi-agent systems. First, a new synchronization approach is presented to synchronize the outputs of heterogeneous agents. Based on noninteracting control techniques, a method is derived for homogenizing the input-output behavior of every agent. Hence, applying the same reference input signal to every agent leads to synchronization. Furthermore, a strategy for increasing the robustness of the synchronization process against exogenous disturbances is presented, which leads to a structurally constrained optimization problem. However, by a convenient reformulation of the problem, well established tools from robust control theory can be used. Moreover, it is shown that this procedure allows to separate the robustness issue from the synchronization task. The effectiveness of the approach is illustrated by a robust output synchronization example for a heterogeneous aircraft fleet.

关键词： heterogeneous networks Multi-agent systems Decentralized control Robust synchronization Disturbance rejection Controller constraints and structure

A Novel Vertical Handoff Algorithm with Dynamic Weights in Wireless heterogeneous networks

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China Communications 2010年第5期7卷 70-76页

作者： Liu Xia Zhao Fangming Jiang Lingge College of Merchant Marine Shanghai Maritime University Shanghai 200135 P. R. China School of Electronic and Electrical Engineering Shanghai Second Polytechnic University Shanghai 201209 P. R. China Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 P. R. China

In order to enhance the quality of vertical handoff in an overlay wireless network, multiple attributes are taken into account when optimizing the vertical handoff decision including user-based and network-based QoS factors. In this paper, we develop a novel vertical handoff algorithm in an integrated 3G cellular and Wireless LAN networks. The proposed algorithm can adjust the weight of each QoS attribute dynamically as the networks change, trace the network condition and choose the optimal access point at transient regions. Simulation results show that this algorithm is able to provide accurate handoff decision, resulting in small unnecessary handoff numbers, good performance of throughput and handoff delay in heterogeneous environments.

关键词： vertical handoff multiple attrbute dynamic weight heterogeneous networks