Received: 4 March 2018
Accepted: 11 October 2018
First Online: 6 November 2018
: Yang Xia received the B.E. degrees from Xi’an Jiaotong University, Xi’an, China, in 2017. He is currently working toward the M.E degree at Nanyang Technological University, Singapore.Bin Gou received the B.S and Ph.D. degrees in electrical engineering from Southwest Jiaotong University, Chengdu, China, in 2010 and 2016, respectively. He is currently a Research Fellow in the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore.Yan Xu received the B.E. and M.E. degrees from South China University of Technology, Guangzhou, China, in 2008 and 2011, respectively, and the Ph.D. degree from The University of Newcastle, Callaghan, N.S.W., Australia, in 2013. He is currently an Assistant Professor with a Nanyang Assistant Professorship in the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore.
: The authors declare that they have no competing interests.