Facing the expected challenges and opportunities of mobile
broadband and IoTs beyond 2020, the network of 5G era is
envisioned to be much more user-centric and scenario adaptive.
This paper gave an overview of such vision and potential
solutions. The 5G network design considerations were elaborated,
where true convergence of information technology
and communication technology is an recurrent scene. Further,
the user-centric network operation was investigated from the
aspects of decoupled control and data, decoupled downlink
and uplink, and adaptive multiple connections. Finally, SDAI
was presented as a unified framework for 5G air interface to
meet the diverse extreme requirements, where a minimum set
of functional blocks capable of reconfiguring into the respective
optimum air interface for various 5G scenarios will be the
design target.