What 5G has been and what should 5G+ be?

Abstract

In this work we aim to provide a comprehensive summary of the most inspiring aspects of 5G mobile networks. In addition, we present the latest findings on the promising 6G technology towards a world of fully digital connectivity. The key determinants are extreme system performance and combinations of requirements for new use cases. We study new performance targets beyond 5G in two stages: 5G+ evolution and new 6G step. Relevant technologies considered too immature for 5G or outside the defined scope are outlined. To justify our vision of future mobile networks, we point out the need for closer collaborations of academia, standardizing bodies, industrial organizations and governments. The contribution strategy is gradual evolution and performance enhancement of mobile communications. Finally, we identify challenges and directions on network technology roadmap toward 6G. Keywords: wireless communication, mobile broadband, low-latency communi-cation, 5G network, 3GPP, 6G vision