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Resource and trajectory optimization in UAV-powered wireless communication system

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Science China(information Sciences) 2021年第4期64卷 54-67页

作者： Weidang LU Peiyuan SI Fangwei LU Bo LI Zilong LIU Su HU Yi GONG College of information Engineering Zhejiang University of Technology School of information Science and Engineering Harbin Institute of Technology School of Computer Science and Electronics Engineering University of Essex National Key Laboratory on communications University of Electronic Science and Technology of China University Key Laboratory of Advanced Wireless communications of Guangdong Province Southern University of Science and Technology

The unmanned aerial vehicle(UAV) is a promising enabler of Internet of Things(IoT) owing to its highly flexible features. Combined with wireless power transfer(WPT) techniques, a UAV can provide energy for IoT nodes, which can extend the lifetime of energy constrained communication systems. This paper studies resource and trajectory optimization in UAV-powered wireless communication systems, which consists of two UAVs and two ground nodes(GNs). The system works in a way that the two UAVs alternately charge the two GNs through wireless power transfer and two GNs also alternately send their information to the corresponding UAV with the harvested energy, which can effectively reduce the interference while receiving the information of GNs. Aiming to maximize the minimum throughput of two GNs, wireless resource and UAVs’ trajectories are jointly optimized with the constraints of UAV collision avoidance, flying speed, and transmit power. Successive convex programming(SCP) and block coordinate descent(BCD) are utilized to solve the optimization problem. Simulation results show that the proposed scheme achieves larger minimum throughput than the benchmark scheme.

关键词： UAV wireless power transfer trajectory optimization resource allocation

Energy-efficient Butler-matrix-based hybrid beamforming for multiuser mm Wave MIMO system

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Science China(information Sciences) 2017年第8期60卷 48-57页

作者： Jiahui LI Limin XIAO Xibin XU Xin SU Shidong ZHOU State Key Laboratory on Microwave and Digital communications Tsinghua National Laboratory for Information Science and TechnologyDepartment of Electronic Engineering Tsinghua University

In order to reduce the cost and power consumption of radio frequency(RF) chains in a millimeterwave(mm Wave) multiple-input multiple-output(MIMO) system, hybrid analog/digital beamforming(HBF)can be utilized to reduce the number of RF chains. The HBF consists of an analog beamforming(ABF) stage and a digital beamforming(DBF) stage. The ABF is always realized by using phase shifters and the DBF is done in a low-dimensional digital domain. However, phase shifters have several drawbacks, such as high power consumption and inconsistency of insertion loss. In this paper, we propose an energy-efficient HBF structure to handle these problems, which utilizes the Butler phase shifting matrix in the ABF stage. With the Butlermatrix-based ABF, several fixed beam directions can be obtained, and the best beam directions of different Butler matrices can be chosen by using exhaustive search. To reduce the high complexity of exhaustive search,we further provide a low complexity HBF algorithm. Simulations under the conditions of perfect channel state information(CSI) and estimated CSI verify the effectiveness of our proposed Butler-matrix-based HBF structure and related algorithms.

关键词： Butler matrix energy-efficient hybrid beamforming MIMO mm Wave multiuser

Generative adversarial networks enhanced location privacy in 5G networks

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Science China(information Sciences) 2020年第12期63卷 41-52页

作者： Youyang QU Jingwen ZHANG Ruidong LI Xiaoning ZHANG Xuemeng ZHAI Shui YU School of information technology Deakin University School of Computer Science University of Technology Sydney National Institute of information and communications technology (NICT) School of information and Communication Engineering University of Electronic Science and Technology of China Center of AI and Big Data Southeast Digital Economic Development Institute

5G networks, as the up-to-date communication platforms, are experiencing fast booming. Meanwhile, increasing volumes of sensitive data, especially location information, are being generated and shared using 5G networks for various purposes ceaselessly. Location and trajectory information in the published data has always been and will keep courting risks and attacks by malicious adversaries. Therefore, there are still privacy leakage threats by simply sharing the original data, especially data with location information, due to the short cover range of 5G signal tower. To better address these issues, we proposed a generative adversarial networks(GAN) enhanced location privacy protection model to cloak the location and even trajectory information. We use posterior sampling to generate a subset of data, which is proved complying with differential privacy requirements from the end device side. After that, a data augmentation algorithm modified from classic GAN is devised to generate a series of privacy-preserving full-sized synthetic data from the central server side. With the synthetic data generated from a real-world dataset, we demonstrate the superiority of the proposed model in terms of location privacy protection, data utility, and prediction accuracy.

关键词： 5G privacy preservation generative adversarial nets differential privacy

Secure coordinated direct and untrusted relay transmissions via interference engineering

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Science China(information Sciences) 2022年第8期65卷 213-227页

作者： Lu LV Zan LI Haiyang DING Yuchen ZHOU Jian CHEN State Key Laboratory of Integrated Services Networks Xidian University National Mobile communications Research Laboratory Southeast University School of information and communications National University of Defense Technology

This paper investigates the physical layer security issue of the coordinated direct and untrusted relay transmissions, considering both uplink and downlink scenarios. To effectively prevent the untrusted relay from eavesdropping on the confidential information it receives, two novel interference-assisted jamming schemes are proposed, where the inter-user interference and the artificial noise are intelligently engineered to degrade the signal reception quality at the untrusted relay, therefore enhancing the physical layer security for the uplink and downlink coordinated transmission, respectively. For each of the two proposed jamming schemes, a lower bound for the ergodic secrecy sum rate(ESSR) is derived in closed form to evaluate the secrecy performance. To obtain more system design insights, we further provide an asymptotic analysis for the ESSR scaling laws over the regimes of the high signal-to-noise ratio and a large number of antennas at the base-station. We carry out computer simulations to confirm the accuracy of the derived theoretical *** simulation results show that the proposed jamming schemes achieve a similar asymptotic performance limit to the case of using a trusted relay. Moreover, the proposed jamming schemes guarantee perfect security for both uplink and downlink coordinated transmissions, and yield a significant ESSR improvement compared with three other baseline schemes.

关键词： physical layer security untrusted relay interference exploitation coordinated transmission ergodic secrecy rate

Beacon-Less Geographic Routing in Real Wireless Sensor Networks

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Journal of Computer Science & technology 2008年第3期23卷 438-450页

作者： Juan A.Sánchez Rafael Marín-Pérez Pedro M.Ruiz Department of information and communications Engineering University of MurciaSpain

Geographic Routing （GR） algorithms require nodes to periodically transmit HELLO messages to allow neighbors to know their positions （beaconing mechanism）. Beacon-less routing algorithms have recently been proposed to reduce the control overheads due to these messages. However, existing beacon-less algorithms have not considered realistic physical layers. Therefore, those algorithms cannot work properly in realistic scenarios. In this paper we present a new beacon-less routing protocol called BOSS. Its design is based on the conclusions of our open-field experiments using Tmote-sky sensors. BOSS is adapted to error-prone networks and incorporates a new mechanism to reduce collisions and duplicate messages produced during the selection of the next forwarder node. We compare BOSS with Beacon-Less Routing （BLR） and Contention-Based Forwarding （CBF） algorithms through extensive simulations. The results show that our scheme is able to *** almost perfect packet delivery ratio （like BLR） while having a low bandwidth consumption （even lower than CBF）. Additionally, we carried out an empirical evaluation in a real testbed that shows the correctness of our simulation results.

关键词： geographic routing beacon-less forwarding performance evaluation real deployment

Modeling and Mining the Temporal Patterns of Service in Cellular Network

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China communications 2015年第9期12卷 11-21页

作者： Sun Weijian Qin Xiaowei Wei Guo Key Laboratory of Wireless-Optical communications Chinese Academy of Sciences School of Information Science and TechnologyUniversity of Science and Technology of China

Recent emergence of diverse services have led to explosive traffic growth in cellular data networks. Understanding the service dynamics in large cellular networks is important for network design, trouble shooting, quality of service(Qo E) support, and resource allocation. In this paper, we present our study to reveal the distributions and temporal patterns of different services in cellular data network from two different perspectives, namely service request times and service duration. Our study is based on big traffic data, which is parsed to readable records by our Hadoop-based packet parsing platform, captured over a week-long period from a tier-1 mobile operator's network in China. We propose a Zipf's ranked model to characterize the distributions of traffic volume, packet, request times and duration of cellular services. Two-stage method(Self-Organizing Map combined with kmeans) is first used to cluster time series of service into four request patterns and three duration patterns. These seven patterns are combined together to better understand the fine-grained temporal patterns of service in cellular network. Results of our distribution models and temporal patterns present cellular network operators with a better understanding of the request and duration characteristics of service, which of great importance in network design, service generation and resource allocation.

关键词： big data cellular network data mining hadoop SOM cluster service

Broadband chaotic light transmitter

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Chinese Optics Letters 2014年第A1期12卷 50-53页

作者：窦欣宇吴晨光陈晓蕾殷洪玺赵清春郝洋赵楠 Laboratory of Optical communications and Photonic technology School of Information and Communication Engineering Dalian University of Technology Dalian 116023 China HAEPC information& Telecommunication Company Zhengzhou 450052 China

A broadband- and photonic-integrated convenient chaotic-light transmitter with both optical feedback and mutual optical-coupling techniques are proposed. Both numerical simulation and experimental results show that the bandwidth of the presented transmitter is much higher than that of the traditional transmitter with only the optical feedback or the mutual optical-coupling; and the influence of optical feedback strength and mutual optical coupling strength on the bandwidth is also investigated numerically.

关键词： Bandwidth

SQoE KQIs Anomaly Detection in Cellular Networks: Fast Online Detection Framework with Hourglass Clustering

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China communications 2018年第10期15卷 25-37页

作者： Xiaowei Qin Shuang Tang Xiaohui Chen DANDan Miao Guo Wei Key Laboratory of Wireless-Optical communications Chinese Academy of Sciences School of Information Science and TechnologyUniversity of Science and Technology of China

The explosive growth of data volume in mobile networks makes fast online diagnose a pressing search problem. In this paper, an object-oriented detection framework with a two-step clustering, named as Hourglass Clustering, is given. Where three object parameters are chosen as Synthetical Quality of Experience（SQo E） Key Quality Indicators（KQIs） to reflect accessibility, integrality, and maintainability of networks. Then, we choose represented Key Performance Indicators（r KPIs） as cause parameters with correlation analysis. For these two kinds of parameters, a hybrid algorithm combining the self-organizing map（SOM） and

关键词： big data SQoE anomaly detection hourglass clustering codebook.

Foundation Study on Wireless Big Data: Concept, Mining, Learning and Practices

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China communications 2018年第12期15卷 1-15页

作者： Jinkang Zhu Chen Gong Sihai Zhang Ming Zhao Wuyang Zhou Key Laboratory of Wireless-Optical communications Chinese Academy of Sciences School of Information Science and Technology University of Science and Technology of China

Facing the development of future 5 G, the emerging technologies such as Internet of things, big data, cloud computing, and artificial intelligence is enhancing an explosive growth in data traffic. Radical changes in communication theory and implement technologies, the wireless communications and wireless networks have entered a new era. Among them, wireless big data(WBD) has tremendous value, and artificial intelligence(AI) gives unthinkable possibilities. However, in the big data development and artificial intelligence application groups, the lack of a sound theoretical foundation and mathematical methods is regarded as a real challenge that needs to be solved. From the basic problem of wireless communication, the interrelationship of demand, environment and ability, this paper intends to investigate the concept and data model of WBD, the wireless data mining, the wireless knowledge and wireless knowledge learning(WKL), and typical practices examples, to facilitate and open up more opportunities of WBD research and developments. Such research is beneficial for creating new theoretical foundation and emerging technologies of future wireless communications.

关键词： wireless big data data model data mining wireless knowledge knowledge learning future wireless communications