Yongjun Xu (Senior Member, IEEE) received the Ph.D. degree (Hons.) in communication and information system from Jilin University, Changchun, China, in 2015. He received the Outstanding Doctoral Thesis of Jilin Province in 2016. He is currently an Associate Professor with the School of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing, China. From 2018 to 2019, he was a Visiting Scholar with Utah State University, Logan, UT, USA. He has authored or coauthored more than 100 papers, including the IEEE Communications Surveys & Tutorials, IEEE Transactions on Vehicular Technology, IEEE Transactions on Cognitive Communications and Networking, IEEE Transactions on Green Communications and Networking, IEEE Internet of Tings Journal, IEEE Communications Letters, IEEE Wireless Communications Letters, etc. His recent interests include heterogeneous networks, resource allocation, intelligent reflecting surface, energy harvesting, backscatter communications, mobile edge computing, UAV communications. He serves as an Associate Editor of EURASIP Journal on Wireless Communications and Networking, an Editor of Physical Communications, an Academic Editor of Digital Communications and Networks. He serves as a reviewer for IET Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Vehicular Technology, IEEE Communications Letters, IEEE Wireless Communications Letters, and China Communications. He was the Technical Program Committee member for many international conferences, such as GLOBECOM, ICC, ICCT, WCNC, ICCC, and CITS.