Ultra-Dense Heterogeneous Networks

Driven by the ever-increasing amount of mobile data, cellular networks evolve from small cell network to ultra-dense heterogeneous networks, to provide high system capacity and spectrum efficiency. By bringing base stations (BSs) to the approximate spatial scale and number magnitude, ultra-dense heterogeneous networks would definitely bring unprecedented paradigm changes to the network design. Firstly, along with densification of small cells, inter-cell interference becomes severe and may deteriorate performance of mobile users. Assigning network resources including bandwidth and time slots, while avoiding interference, desires serious consideration. Secondly, the coverage area of BSs becomes small and irregular, resulting in much frequent and complicated handovers when mobile users move around. How to ensure continuous communication and implement effective mobility management, and inter-cell resource allocation and cooperation, remains a challenging issue. Thirdly, such dynamic change in spatial dimension enables us to re-investigate available and ongoing communications and networking techniques, such as massive MIMO, CoMP, millimeter waves (mmWaves), carrier aggregation, full duplex radio, and D2D communications.

To address the aforementioned challenging research issues, this book will investigate the service and QoE provisioning in ultra-dense heterogeneous networks. In particular, firstly we introduce ultra-dense heterogeneous networks by careful definition regarding spatial deployment, generic characteristics, and requirements of ultra-dense heterogeneous networks in order to ensure QoE of mobile users. Secondly, we depict the resource management among small cells in close proximity, mobility management for mobile users (address the super-frequent handovers), and interference management (dealing with the interference due to frequency-reuse in the vicinity). Thirdly, we study the enabling factors, and the integration of ultra-dense heterogeneous networks with enabling technologies, such as massive-MIMO, cloud-RAN, mmWaves, D2D, IoT. Finally, we conclude the book and indicate future directions and challenges.

由於移動數據量不斷增加，蜂窩網絡從小型蜂窩網絡發展為超高密度異構網絡，以提供高系統容量和頻譜效率。超高密度異構網絡將基站（BS）帶到近似的空間尺度和數量級，必然對網絡設計帶來前所未有的範式變革。首先，隨著小型蜂窩的密集化，蜂窩間干擾變得嚴重，可能會損壞移動用戶的性能。在避免干擾的同時，分配網絡資源，包括頻寬和時隙，需要嚴肅考慮。其次，基站的覆蓋區域變小且不規則，當移動用戶移動時，手動切換頻繁且複雜。如何確保連續通信，實現有效的移動管理，以及蜂窩間資源分配和合作，仍然是一個具有挑戰性的問題。第三，空間尺度的動態變化使我們能夠重新研究可用和正在進行的通信和網絡技術，例如大規模MIMO、CoMP、毫米波（mmWaves）、載波聚合、全雙工無線電和D2D通信。

為了解決上述具有挑戰性的研究問題，本書將研究超高密度異構網絡中的服務和QoE提供。具體而言，首先我們通過對超高密度異構網絡的空間部署、通用特性和要求進行仔細定義，以確保移動用戶的QoE。其次，我們描述了鄰近小型蜂窩之間的資源管理，移動用戶的移動管理（解決超頻繁的手動切換），以及干擾管理（處理附近頻率重用引起的干擾）。第三，我們研究了超高密度異構網絡與大規模MIMO、雲RAN、毫米波、D2D、物聯網等啟用技術的整合和促進因素。最後，我們總結本書並指出未來的方向和挑戰。

Wen Sun is currently a professor in Northwestern Polytechnical University. She received her Ph.D. degree in Electrical and Computer Engineering from National University of Singapore in 2014, and B.E. degree from Harbin Institute of Technology in 2009. She was a research fellow in National University of Singapore from 2014 to 2015. Her research interests cover a wide range of areas including wireless mobile communications, IoT, 5G, and blockchain. She has published more than 50 peer-reviewed papers in various prestigious IEEE journals and conferences, including IEEE Transactions on Industrial Informatics, IEEE Transactions on Wireless Communications, IEEE Network, IEEE Wireless Communications. She was the recipient of the best paper award of GlobeCom2019. She is IEEE senior member and serves as publicity chair for WiMob2019 and CNS2020, and TPC member for ICC and GlobeCom in 2018 and 2019. She also serves as an associate editor for International Journal of Multimedia Intelligence and Security and IEEE Access.

Qubeijian Wang is currently an assistant professor with the School of Cybersecurity, Northwestern Polytechnical University, China. He received the B.E. degrees in electrical engineering from Xi'an Jiaotong-Liverpool University, China, and the University of Liverpool, U.K., in 2015, the M.E. degree in telecommunications from the University of Melbourne, Australia, in 2017, and the Ph.D. degree in electronic information technology from Macau University of Science and Technology, Macau. His research interests include UAV-aided communications, physical-layer security, and large-scale network performance analysis. He serves as TPC member for conferences, including GlobeCom 2021 and 2022, and VTC2021-Fall and reviewer for various prestigious IEEE journals and conferences.

Nan Zhao is currently a Professor at Dalian University of Technology, China. He received the B.S. degree in electronics and information engineering in 2005, the M.E. degree in signal and information processing in 2007, and the Ph.D. degree in information and communication engineering in 2011, from Harbin Institute of Technology, Harbin, China. His recent research interests include UAV Communications, Interference Alignment, and Physical Layer Security. Dr. Zhao is serving or served on the editorial boards of 9 SCI-indexed journals, including IEEE Wireless Communications Letters and IEEE Transactions on Green Communications and Networking. He received Top Reviewer Award from IEEE Transactions on Vehicular Technology in 2016, and was nominated as Exemplary Reviewers by IEEE Communications Letters in 2016 and by IEEE Transactions on Communications in 2018 and 2019. He won the best paper awards in IEEE VTC 2017 Spring, ICNC 2018, WCSP 2018 and WCSP 2019. He also received the IEEE Communications Society Asia Pacific Board Outstanding Young Researcher Award in 2018.

Chao Shen is a full Professor in the faculty of Electronic and Information Engineering, Xi'an Jiaotong University of China. He currently serves as the Associate Dean of School of Cyber Science and Engineering of Xi'an Jiaotong University. He received the B.S. degrees in automatic control and the Ph.D. degree in system engineering from Xi'an Jiaotong University, Xi'an, China, in 2007 and 2014, respectively. He was a research scholar in Computer Science Department at Carnegie Mellon University from 2011 to 2013. He has published more than 70 research papers in international referred journals and conferences at the intersection of computer and network security, big data analysis, machine learning and automatic control. His current research interests mainly include Data-Driven Network and System Security, AI Security, Cyber-Physical System Security. He currently serves as an Associate Editor for a number of journals, including Journal of Franklin Institute, Frontiers of Computer Science, and Engineering.

Lawrence Wong is Professor in the Department of Electrical and Computer Engineering, National University of Singapore (NUS). He was Vice President of IEEE from 2014 to 2017. He is currently holding the position of Deputy Director (Strategic Development) at the Interactive and Digital Media Institute (IDMI) in NUS. He was previously Executive Director of the Institute for Infocomm Research (I2R) from Nov 2002 - Nov 2006. Since joining NUS in 1983, he served in various positions at the department, faculty, and university levels, including Head of the Department of Electrical and Computer Engineering from Jan 2008 - Oct 2009, Director of the NUS Computer Centre from Jul 2000 - Nov 2002, and Director of the Centre for Instructional Technology from Jan 1998 - Jun 2000. Prior to joining NUS in 1983, he was a Member of Technical Staff at AT&T Bell Laboratories, Crawford Hill Lab, NJ, USA, from 1980 to 1983. He received the B.Sc. (1st class Honours) and Ph.D. degrees in Electronic and Electrical Engineering from Loughborough University, UK, in 1976 and 1980, respectively. His research interests include wireless networks and systems, multimedia networks, and source matched transmission techniques with over 200 publications and 4 patents in these areas. He is co-author of the book on "Source-Matched Mobile Communications". He received the IEEE Marconi Premium Award in 1989, NUS Teaching Award (1989), IEEE Millennium Award in 2000, the e-nnovator Awards 2000, Open Category, and Best Paper Award at the IEEE International Conference on Multimedia and Expo (ICME) 2006.

溫孫目前是西北工業大學的教授。她於2014年從新加坡國立大學獲得電氣與電腦工程博士學位，並於2009年從哈爾濱工業大學獲得學士學位。她曾在2014年至2015年期間擔任新加坡國立大學的研究員。她的研究興趣涵蓋無線移動通信、物聯網、5G和區塊鏈等多個領域。她在各種著名的IEEE期刊和會議上發表了50多篇同行評審的論文，包括《IEEE工業信息學報》、《IEEE無線通信學報》、《IEEE網絡》和《IEEE無線通信》。她是GlobeCom2019最佳論文獎的獲獎者。她是IEEE高級會員，並擔任WiMob2019和CNS2020的宣傳主席，以及2018年和2019年ICC和GlobeCom的TPC成員。她還擔任《國際多媒體智能與安全期刊》和《IEEE Access》的副編輯。

王曲北見目前是西北工業大學網絡安全學院的助理教授。他於2015年在中國西安交通-利物浦大學和英國利物浦大學獲得電氣工程學士學位，2017年在澳大利亞墨爾本大學獲得電信學碩士學位，並於澳門科技大學獲得電子信息技術博士學位。他的研究興趣包括無人機輔助通信、物理層安全和大規模網絡性能分析。他擔任GlobeCom 2021和2022以及VTC2021-Fall的TPC成員，並為多個著名的IEEE期刊和會議擔任審稿人。

趙南目前是中國大連理工大學的教授。他於2005年獲得電子與信息工程學士學位，2007年獲得信號與信息處理碩士學位，2011年獲得信息與通信工程博士學位，這些學位都是在中國哈爾濱工業大學獲得的。他最近的研究興趣包括無人機通信、干擾對齊和物理層安全。趙博士是9個SCI收錄期刊的編輯委員會成員，包括《IEEE無線通信信函》和《IEEE綠色通信和網絡學報》。他於2016年獲得IEEE車輛技術期刊的最佳審稿人獎，並於2016年被IEEE通信信函和2018年、2019年被IEEE通信學報提名為優秀審稿人。他在IEEE VTC 2017 Spring、ICNC 2018、WCSP 2018和WCSP 2019上獲得了最佳論文獎。他還於2018年獲得了IEEE通信學會亞太區傑出青年研究者獎。

沈超是中國西安交通大學電子與信息工程學院的教授。他目前擔任西安交通大學網絡科學與工程學院的副院長。他於2007年和2014年分別在西安交通大學獲得自動控制學士學位和系統工程博士學位。他曾在2011年至2013年期間在卡內基梅隆大學計算機科學系擔任研究學者。他在計算機和網絡安全、大數據分析、機器學習和自動控制交叉領域發表了70多篇研究論文。他目前的研究興趣主要包括數據驅動的網絡和系統安全、人工智能安全和物理層系統安全。他目前擔任多個期刊的副編輯，包括《富蘭克林學會學報》、《計算機科學前沿》和《工程學報》。

劉瑞是中國西安交通大學電氣與計算機工程系的教授。