A mmWave Cloud Cooperated and Mobility Dependant Scheme for 5G Cellular Networks

The unavoidable and dramatic increase of mobile traffic load predicted to hit future cellular networks, has operated as a catalyst for the 51h generation (5G) mobile networks to envision the support of higher data rates by a factor of 1,000 in the next 10 years. The utilization of the ultrawideband aspect of the mmWave bands has recently risen as a quite promising candidate that could support such an overwhelming demand. Armed with the exploitation of such high frequencies, several studies have proposed a logical split between the control plane (C-plane) operated by macro basestations (BSs) at the 2GHz band and the user plane (U-plane) operated by pico base stations at much higher frequencies (e.g. 3GHz or 60GHz bands). Thus, a heterogeneous cellular network (C-HetNet) is built, where macro and pico BSs could potentially function in a cooperative manner by connecting to a cloud radio access network (C-RAN). Despite the fact that such architecture provides a more efficient approach for handling signalling and user traffic, the use of mmWave bands introduces some major challenges. An appropriate user association scheme is still needed in order to successfully associate a specific user with a particular pico BS before user data transmission is initiated. It is clear that the process followed for user associations and re-associations introduces considerable latency; therefore high user equipment (UE) mobility may negatively affect user experience by demanding very frequent initiations of that process. In this paper, the author proposes a fair, user traffic off-loading mechanism, where highly mobile UEs, after a given grace period, are forced to shift the transmission of user data from the U-plane to the C-plane until the point where they become more stationary. Ultimately, this approach results in a lower amount of user re-associations needed as a trade-off to mobility and in the expense of lower data rates.