YU ZHANG, PhD, is a professor in the School of Electronic Engineering at Xidian University in Xi'an, China.

TAPAN K. SARKAR, PhD, is a professor in the Department of Electrical Engineering and Computer Science at Syracuse University, New York, USA.

XUNWANG ZHAO, PhD, is an associate professor in the School of Electronic Engineering at Xidian University, Xi'an, China.

DANIEL GARCIA-DOÑORO is a PhD student in the Department of Signal Theory and Communications at Universidad Carlos III de Madrid in Madrid, Spain.

WEIXIN ZHAO is a PhD student in the Department of Electrical Engineering and Computer Science at Syracuse University, New York, USA.

MAGDALENA SALAZAR-PALMA, PhD, is a professor in the Department of Signal Theory and Communications at Universidad Carlos III de Madrid, Spain.

SIOWENG TING, PhD, is an assistant professor in the Department of Electrical and Computer Engineering at the University of Macau, China.