How a Layered REM Architecture Brings Cognition to Today's Mobile Networks
In this paper, the authors present a layered Radio Environment Map (REM) architecture along with its applications to the Self-Organizing Network (SON) functionalities of heterogeneous LTE radio-access networks comprising macrocells and femtocells. In this architecture, the functional blocks re-appear with different spatial and temporal granularity at different architectural layers. Although, REM is one of the key promising technologies to enable future cognitive radio networks, it can be already applied to provide limited cognitive capabilities to today's commercial networks too. They explain why, and show how; this architecture can support today's LTE SON functions like Automatic Neighbor Relation (ANR) and Minimization of Drive Tests (MDT), and also allows the smooth introduction of new Radio Access Technologies (RATs) through refarming.