1.报告题目：Massive Multiple-Access for 5G IoT

报告摘要：  Future 5G IoT networks are expected to be the ultra-dense wireless networks aiming at provid-ing a wide-range of services, from high-rate continuous applications to low-rate sporadic short-burst services. Motivat-ing to provide sporadic short-burst IoT traffic of requiring massive connectivity, the radio access techniques based on the traditional multiple-access schemes used, such as, in LTE/LTE-A, are inefficient, due to the resultant high overhead ratio or/and their infeasiblity of supporting massive connectivity. Therefore, in this talk, we first address the main chall-enges of radio access in 5G massive IoT networks. Then, aiming for massive connectivity or/and  overhead ratio redu-ction, the problems and technical solutions for both granted and grant-free massive access are explored based on our recent research. A range of multiple-access and detection schemes that are suitable for operation in heavily loaded IoT systems will be discussed. We compare their advantages, disadvantages and challenges, when practical implemen-tation issues are considered. The talk will be concluded with discussing some open problems for future research.

报告人：英国南安普顿大学杨列亮教授

报告时间：2018年11月2日 上午10：00

报告地点：理六525

邀请人：张涵教授 穆丽伟副教授

杨列亮（Lie-Liang Yang）教授简历：

   Lie-Liang Yang received his M.Eng and Ph.D degrees in communications and electronics from Northern (Beijing) Jiaotong University, Beijing, China in 1991 and 1997, respectively, and his B.Eng degree in communications engineering from Shanghai Tiedao University, Shanghai, China in 1988. Additionally, he received a Postgraduate Certificate in Education from University of Southampton,Southampton, UK in 2005.

   From June 1997 to December 1997 he was a visiting scientist to the Institute of Radio Engineering and Electronics, Academy of Sciences of the Czech Republic. Since December 1997, he has been with the School of Electronics and Computer Science, Uni-versity of Southampton, UK, where he was first a Postdoctoral Research Fellow (Dec. 1997 - Aug. 2002), then a Lecturer (Sept. 2002 - Feb. 2006), then a Reader (Mar. 2006 - June 2010) and has been the Professor of Wireless Communications since June 2010. He has research interest in a range of areas in wireless communications, wireless networks and signal processing for wireless com-munications, as well as molecular and nano communications. He published 300+ research papers, which incl-ude 130+ journal pa-pers and 200+ conference papers. He authored one book entitled Multicarrier Communications, which was published by John Wi-ley & Sons. This book was also translated into Chinese and publi-shed by the Publishing House of Electronic Industry of China. He coauthored two books entitled Single- and Multi-Carrier DS-CDMA - Multiuser Detection, Space-Time Spreading, Synchroniza-tion and Standards and Near-Capacity Variable-Length Coding, respectively, both of which were jointly published by John Wiley & Sons and IEEE Press. Additionally, he published 10+ book chapters.

   Prof. Yang is a Fellow of the IEEE in the USA, and a Fellow of the IET (previously IEE) in the UK. He is a Distinguished Lec-turer of the IEEE Vehicular Technology Society. He acted as TPC/symposium/area/track/workshop chairs for various con-ferences and was involved in the teams of Technical Programme Committees (TPC) of many conferences. He served as an ass-ociate editor to the IEEE Transactions on Vehicular Technology, Journal of Communications and Networks (JCN), etc., and he is currently an associate editor to the IEEE Access and the Security and Communication Networks (SCN) Journal. He was/is one of the guest edi-tors for the special issues in: IEEE Journal on Selected Areas in Communications (2013), IEEE Wireless Comm-unication Maga-zine (2013), IEEE Communication Magazine (2014), IEEE Systems Journal (2015), EURASIP Journal on Wireless Communica-tions and Networking (2011).

2.报告题目：复杂场景下异构无线传感器网络的节点定位技术研究

报告摘要：在无线传感器网络中（WSN），节点位置信息的获取对于感知信息的应用至关重要，因为在数据分析中，缺少了具体位置信息的感知数据的价值将会大打折扣。然而在实际的应用场景中，有许多环境以及网络拓扑的因素，会影响准确的节点定位，例如由障碍物造成的覆盖空洞会为多跳网络的传输路径带来迂回，影响距离估计的准确性；另外，边界效应会导致网络中某个区域的信标节点分布不均匀，降低节点的定位精度。为了降低由复杂环境带来的定位误差，提出了两种节点定位技术，一是基于统计学方法，用网络的局部特征估计整体特征，根据信标节点的可靠度对节点对进行分类，对不同类别的节点对采用相应的距离估计方案。二是利用人工智能方法，以节点跳数向量作为输入，学习网络中节点的分布、链路平均跳数以及平均每跳前进等特征，再对节点间的距离或者常规节点的位置直接进行估计。仿真分析结果表明这两种方案均可以在很大程度上降低由环境因素引起较大的定位误差，在复杂场景下能获得较明显的性能增益。

报告人：中山大学刘星成教授

报告时间：2018年11月2日 上午11：00

报告地点：理六525

邀请人：张涵教授 穆丽伟副教授

刘星成教授简介：刘星成，博士，教授，博士生导师。IEEE高级会员，中国计算机学会物联网专委会委员。先后获得华中科技大学学士和硕士学位、中山大学博士学位。先后赴英国Southampton大学和美国Oregon州立大学做博士后和访问学者。主要从事无线传感器网络/物联网、网络编码及协作通信、信道编码技术、无线移动通信新技术等方面研究。近年来主持完成了多个国家自然科学基金项目和省市级科研项目，发表学术论文100多篇，合作出版教材2本，获国家发明专利10多项，申请专利5项。是国家科技奖、国家自然科学基金项目和多个省市科技项目的评审专家。

代表性科研成果:

近年来部分论著 Recent publications：

[1] Xingcheng Liu, Chunlei Fan, Xuechen Chen, Dynamic Scheduling Decoding of LDPC Codes Based on Tabu Search, IEEE Transactions on Communications, 2017. (Click here for PDF).

[2] Xingcheng Liu, Xingcheng Liu, Wei Li, Feng Han, and Yi Xie, An Optimization Scheme of Enhanced Adaptive Dynamic Energy Consumption Based on Joint Network-Channel Coding in WSNs, IEEE Sensors Journal, September 2017. SCI indexed. (Click here for PDF). SCI Indexed.

[3] Xingcheng Liu, Zhenzhu Zhou, Ru Cui, Erwu Liu, Informed Decoding Algorithms of LDPC Codes Based on Dynamic Selection Strategy, IEEE Transactions on Communications, April 2016. (Click here for PDF). SCI Indexed.

[4]   Xingcheng Liu，Nandi Xiong, Wei Li, Yi Xie, An Optimization Scheme of Adaptive Dynamic Energy Consumption Based on Joint Network-Channel Coding in Wireless Sensor Networks, IEEE Sensors Journal, 2015. (Click here for PDF). SCI Indexed.

[5]   Xingcheng Liu, Feng Xiong, Zhenzhu Zhou, Y. Yin, and Lin Zhang, Construction of QC LDPC Cycle Codes over GF(q) Based on Cycle Entropy and Applications on Patterned Media Storage, IEEE Transactions on Magnetics, 2015. (Click here for PDF). SCI Indexed.

[6]   Xingcheng Liu，Chulong Liang, Yuanbin Zhang, and Lin Zhang, Decoding of Non-binary LDPC Codes Based on the Genetic Algorithm and Applications over Mobile Fading Channels, IET Communications, Jun. 2015. (Click here for PDF). SCI Indexed.