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Swarm intelligence approaches to power allocation for downlink base station cooperative system in dense cellular networks

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Science China(Information Sciences) 2020年第6期63卷 244-246页

作者： Hailin XIAO zhongshan zhang School of Computer Science and Information Engineering Hubei University School of Information and Electronics Beijing Institute of Technology

Dear editor,5G will be ultra-dense networks and heavily sliced to support the substantial increase of mobile devices involving high-rate applications. However,the massive number of base stations (BSs) deployed will inevitably lead to inter-cell interference [1]. A promising approach for reducing intercell interference is multiple BSs cooperative transmission, also known as coordinated multi-point(CoMP) transmission [2].

关键词： Swarm intelligence approaches to power allocation for downlink base station cooperative system in dense cellular networks

A user-selected uplink power control algorithm in the two-tier femtocell network

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Science China(Information Sciences) 2015年第4期58卷 51-62页

作者： CHAI XiaoMeng XU Xu zhang zhongshan Institute of Advanced Network Technology and New Services University of Science and Technology Beijing

In two-tier femtocell networks, the frequency reuse among cells leads to cross-tier interference(CTI),the primary constraint to system performance improvement. In order to alleviate the impact of CTI, we propose a user-selected power control algorithm based on the non-cooperative game theory in consideration of user diversity gain. In the proposed scheme, the macro-user with high channel gain and the femto-user with low channel gain at the macro base station are scheduled to be "active" in one slot but to be "opposite" in next slot in order to achieve an optimal overall performance. Numerical results show that the proposed scheme is capable of outperforming the traditional stochastic schedule strategy by more than 30% improvement in terms of average macrocell capacity. Furthermore, an obvious performance gain in the percentage femtocells beyond its signal-to-interference-and-noise ratio(SINR) target can also be achieved by executing the macrocell link-quality-protection strategy.

关键词： power control game theory user-selected femtocell macrocell capacity

UAPM: An Urgency-Aware Packet Management for Disaster Management Using Flying Ad-Hoc Networks

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China Communications 2019年第11期16卷 167-182页

作者： Ali Khan Farooq Aftab zhongshan zhang School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China.

The ever increasing demand of adhoc networks for adaptive topology and mobility aware communication led to new paradigm of networking among Unmanned Aerial Vehicles(UAVs)known as Flying ad-hoc Networks(FANETs).Due to their dynamic topology,FANETs can be deployed for disaster monitoring and surveillance *** these operations,UAVs need to transmit different disaster data,which consists of different types of data *** them there are packets which need to be transmitted urgently because of the emergency situation in disaster *** handle this situation,we propose a methodology of disaster data classification using urgency level and based on these urgency levels,priority index is assigned to data *** approach of Urgency Aware Scheduling(UAS)is proposed to efficiently transmit high and low priority packets with minimum delays in transmission *** take into account different scenarios of UAVs for disaster management and for N number of UAVs,we propose bio-inspired mechanism using behavioral study of bird flocking for cluster formation and ***,we propose a priority based route selection methodology for data communication in FANET *** show that our proposed mechanism shows better performance in the presence of evaluation benchmarks like average delay,queuing time,forward percentage and fairness.

关键词： FANETs disaster management data priority clustering self-organization

Physical layer security via maximal ratio combining and relay selection over Rayleigh fading channels

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Science China(Information Sciences) 2016年第6期59卷 167-176页

作者： Bin ZHONG Minggang WU Tong LI zhongshan zhang School of Information and Electrical Engineering Hunan University of Science and Technology Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services University of Science and Technology Beijing

In this paper, the impact of both maximal ratio combining(MRC) and relay selection on the physical layer security in wireless communication systems is investigated by analyzing critical issues such as the probability characteristics of the legitimate receiver(Bob) and malicious eavesdropper(Eve)’s end-to-end signal-to-noise ratio(SNR), the secrecy outage probability and the average secrecy channel capacity over Rayleigh fading Channel, etc. Unlike the conventional physical layer security schemes, we assume that Bob receives its data from both the relay and the source via cooperative relay, provided that MRC is employed at the ***, compared to the conventional MRC methods, the proposed method is capable of achieving a higher spatial diversity order by performing relay selection, as validated by performing the theoretical analysis as well as numerical simulation. Furthermore, the closed-form expressions in terms of secrecy outage probability and average secrecy capacity are all consistent with the numerical results. Finally, the proposed scheme may be substantially affected by a number of parameters such as the number of relays, the SNR of links and the ratio of main-to-eavesdropper ratio(MER) λME.

关键词： average secrecy capacity cooperative communication maximal ratio combining outage probability physical layer security

Survivability-oriented optimal node density for randomly deployed wireless sensor networks

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Science China(Information Sciences) 2014年第2期57卷 285-290页

作者： HUANGFU Wei zhang zhongshan CHAI XiaoMeng LONG KePing Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services University of Science and Technology Beijing (USTB) National Mobile Communications Research Laboratory Southeast University

The survivability is usually critical for wireless sensor networks,which are often deployed in the unattended harsh *** of technical schemes to improve the survivability depend on the redundant resources of the sensor *** amount of resources is usually determined by the node density during the deployment *** the random deployment and random node failures,the quantitative relation between the survivability and the node density is *** on the conditional survivability,the node density to meet the required survivability level is ***,the survivability for unpredictable failures and the optimal node density to maximize the price–performance ratio are also discussed.

关键词： wireless sensor network survivability random deployment node density random failure

An overview of protected satellite communications in intelligent age

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Science China(Information Sciences) 2021年第6期64卷 126-143页

作者： Changhong WANG zhongshan zhang Jiayi WU Chaofan CHEN Fei GAO School of Information and Electronics Beijing Institute of Technology

Protected satellite communications(SatComs) exhibit specific characteristics such as security,intelligence, anti-jamming, and nuclear disaster survivability. They constitute one of the key research topics in modern military communications and have become the basic means for implementing strategic and tactical command and control. Currently, the United States military is using the latest advanced extremely high-frequency(AEHF) system to provide protected communications. Other countries are also employing their own protected SatCom systems to meet future operational requirements. Furthermore, in the modern intelligent age, many intelligent-related technologies are introduced into the protected SatCom systems to provide more secure and efficient communication services. In this paper, a comprehensive overview of the protected SatCom systems is presented. More specifically, a system overview of the protected SatComs is illustrated. Our focus is placed on the critical technologies and practical applications, and finally discuss remaining challenges and look forward to the future research directions. It is undoubted that the protected SatCom is one of the most important systems in military communications, both now and in the future.

关键词： SatCom protected communication intelligent AEHF

Predictive Decision and Reliable Accessing for UAV Communication in Space-Air-Ground Integrated Networks

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China Communications 2022年第1期19卷 166-185页

作者： Bowen Zeng zhongshan zhang Xuhui Ding Xiangyuan Bu Jianping An School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

The cooperation of multiple Unmanned Aerial Vehicles(UAVs) has become a promising scenario in Space-Air-Ground Integrated Networks(SAGINs) recently due to their widespread applications,where wireless communication is a basic necessity and is normally categorized into control and nonpayload communication(CNPC) as well as payload communication. In this paper, we attempt to tackle two challenges of UAV communication respectively on establishing reliable CNPC links against the high mobility of UAVs as well as changeable communication conditions, and on offering dynamic resource optimization for Quality-of-Service(QoS) guaranteed payload communication with variable link connectivity. Firstly, we propose the concept of air controlling center(ACC), a virtual application equipped on the infrastructure in SAGINs, which can collect global information for estimating UAV trajectory and communication channels. We then introduce the knapsack problem for modelling resource optimization of UAV communication in order to provide optimal access points for both CNPC and payload communication. Meanwhile, using the air controlling information, predictive decision algorithm and handover strategy are introduced for the reliable connection with multiple access points. Simulation results demonstrate that our proposal ensures an approximate always-on reliable accessing of communication links and outperforms the existing methods against high mobility,sparse distribution, and physical obstacles.

关键词： space-air-ground integrated networks UAV communication air communication controlling predictive decision reliable accessing

Geochemical characteristics of the Xuanwei Formation in West Guizhou:Significance of sedimentary environment and mineralization

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Chinese Journal Of Geochemistry 2010年第4期29卷 355-364页

作者： zhang Zhengwei YANG Xiaoyong LI Shuang zhang zhongshan State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black *** is～170 m thick at Cuyudong Village,Weining County,West Guizhou,China,where the samples of black shale and sandy shale were collected and *** shales mainly contain SiO2,18.9%?44.1%,Al2O3,14.8%?52.8%,Fe2O3,1.0%?41.2%,LOI,3.2%?21.1%,TiO2,1.0%-6.7%,and MgO,0.2%?2.5%.The contents of all other major elements are lower than 1.0%.It is shown that the black shales have higher contents of Fe2O3 and LOI than normal *** siderites occurred in the black shales with higher contents of Fe2O3,which may be attributed to hydrothermal activities on *** analyzed shale samples have extremely high Ga,47.8×10-6-109.9×10-6(70.5×10-6 on average),higher than the industrial mining standard of Ga Resource Industry *** total contents of rare-earth elements(REE) of 9 black shale samples vary from 213×10-6 to 1460×10-6,suggesting that these black shales are enriched in *** shale-normalized REE patterns display both positive and negative Ce anomalies(Ce/Ce* from 0.5 to 1.7),revealing that the Xuanwei shales were precipitated under oxic and anoxic *** Rb-Sr chronological diagram of 6 shale samples in the Xuanwei Formation shows an age of 255±12 *** isotopic ratios(87Sr/86Sr)t0 range from 0.70635 to 0.70711,suggesting that these Xuanwei black shales might be derived from chemical weathering of the Emeishan basalts.

关键词：贵州西部地球化学特征宣威组成矿作用沉积环境峨眉山玄武岩黑色页岩稀土元素

Network for hypersonic UCAV swarms

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Science China(Information Sciences) 2020年第4期63卷 112-139页

作者： Shixun LUO zhongshan zhang Shuai WANG Shuo zhang Jibo DAI Xiangyuan BU Jianping AN School of Information and Electronics Beijing Institute of Technology National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing Aerospace Automatic Control Institute

Unmanned combat aerial vehicles(UCAVs) that swarm with both autonomous decision-making and cooperative attacking have been regarded as revolutionary elements of modern warfare. In such a swarm,inter-group connectivity must be ensured in a network to maintain a collective consensus. In recent years,academia and industry have made many efforts to achieve common tactical data link systems and commercial drone networks. However, the existing results have difficulty meeting the needs of cooperative autonomous UCAV swarms with both hypersonic mobility and time sensitivity in severe confrontation scenarios. In this article, we conduct an in-depth investigation of the network used for the hypersonic UCAV swarms,which can be considered as a special form of mobile wireless network. Furthermore, faced with specific functional demands, we summarize the main challenges of designing this dedicated network. In addition,a comprehensive survey of potential solutions for the network design is presented. Lastly, we discuss the possible capabilities of the network given the current forefront of technology, as well as remaining challenges and open issues.

关键词： military communication machine-to-machine communications multi-UCAV networks ad hoc networks wireless mesh networks unmanned aerial vehicles cross layer design