Blockage-Robust 5G mm-Wave Access Network Planning

Mm-wave technologies are a promising solution to provide ultra-high capacity in 5G wireless access networks. However, the potential of several-GHz bandwidths must coexist with a harsh propagation environment. While high attenuations can be compensated by advanced antenna systems, the severe obstacle blockage effect can only be mitigated by more sophisticated network managements. One of the most widely adopted techniques to guarantee a reliable service in mm-wave access scenarios is to establish multiple connections from the mobile to the different base stations. However, the advantage of multiple mm-wave connections can be fully exploited only if uncorrelated channels are available, thus spatial diversity must be ensured. Although smart base station selections could be made once the network is deployed, much better results are achievable if high-diversity selection aspects are already included in the network planning phase. In this paper, we propose for the first time a mm-wave access network planning framework which considers both spatial diversity among potential base-station selection candidates and user achievable throughput, according to channel conditions and network congestion. The results show that our approach allows to obtain much better spatial diversity conditions than traditional k-coverage approaches, and this can indeed provide higher robustness in presence of sudden obstacles.