Fifth generation mobile communications (5G) are expected to accommodate rapidly increasing mobile traffic aiming at the realization of a “Hyper Connected World” in which all people and surrounding things are connected and information is exchanged between them, and to play the role of a basis of the Internet of everything. A lot of research projects have started focusing on the research of 5G since around 2013, and some agreements are being formed about the vision and the candidate technologies of 5G. The 5G wireless network is expected to become a “Heterogeneous Network” where new wireless access technologies incompatible with 4G and the wireless access technologies for unlicensed band are incorporated with the enhanced technology of 4G (e.g. IMT-advanced). This paper introduces the vision and technology trends of 5G, shows key directions of the research and development of 5G in the future, and introduces some of our studies on 5G.
