Anirban Bhowal received the Ph.D. degree from the Department of Electronics and Electrical Engineering, Indian Institute of Technology Guwahati, in 2020. He is presently associated as a postdoctoral research fellow at the INRS-EMT, Universite du Quebec, Montreal (QC), Canada. He completed his B.Tech. in electronics and communication engineering from the Heritage Institute of Technology, Kolkata, in 2012. He received his M.Tech. degree in communication engineering from the Indian Institute of Information Technology, Allahabad, in 2015. His research interests include spatial modulation in RF and FSO systems, UOWC and FSO cooperative systems, hybrid FSO/RF communication, and BAN communication.  Rakhesh Singh Kshetrimayum received his Ph.D. from the School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore, and B.Tech. in Electrical Engineering from the Indian Institute ofTechnology Bombay, India. He is currently a Professor in the Department of EEE, IIT Guwahati, India. His research interests are in the broad areas of printed antennas, passive microwave devices, spatial modulation, cooperative communications, and optical wireless communications. He has published several journal and conference papers. He is a Fellow of the IET, UK, and a senior member of the IEEE, USA.