His research interests include wireless resource allocation and management, physical layer security, wireless communications and networking, game theory, wireless multimedia, and smart grid communication. He was the MAC symposium vice chair of IEEE WCNCÕ08, Wireless Communications symposium co-chair of VTCÕ11-Fall, and organizers of various workshops. He is Associate Editor of IEEE Transactions on Wireless Communications. He is an NSF CAREER award recipient in 2010 and he has received several Best Paper Awards in recent years, including IEEE Wireless Communications Magazine Best Paper Award. Prof. Han has significant publications in the area of communication security and has given a Tutorial on Resource Allocation in Wireless Physical Layer Security at WCNCÕ13.