  In this article, the prospects and enabling technologies for high-efficiency
device positioning and location-aware communications in emerging 5G networks
are reviewed. We will first describe some key technical enablers and
demonstrate by means of realistic ray-tracing and map based evaluations that
positioning accuracies below one meter can be achieved by properly fusing
direction and delay related measurements on the network side, even when
tracking moving devices. We will then discuss the possibilities and
opportunities that such high-efficiency positioning capabilities can offer, not
only for location-based services in general, but also for the radio access
network itself. In particular, we will demonstrate that geometric
location-based beamforming schemes become technically feasible, which can offer
substantially reduced reference symbol overhead compared to classical full
channel state information (CSI)-based beamforming. At the same time,
substantial power savings can be realized in future wideband 5G networks where
acquiring full CSI calls for wideband reference signals while location
estimation and tracking can, in turn, be accomplished with narrowband pilots.
