Dynamic LSA for 5G networks The ADEL perspective

Exploiting additional radio spectrum is key to re-spond to the unprecedented capacity demands of mobile broad-band communication systems in recent years. In fact, most of the frequency bands suitable for mobile communications are already in use by other radio services, and spectrum refarming is usually not possible or constitutes a highly time-consuming procedure. At the same time, several field measurement campaigns have shown that the occupied spectrum below 6GHz is severely underutilized, i.e. there exist "spectrum holes" in the time, frequency, and space dimensions, pointing to the possibility of using spectrum sharing as a mean to better exploit additional spectral resources. Li-censed shared access (LSA) is a recent spectrum licensing para-digm that allows licensees to share the licensed spectrum of in-cumbents without causing harmful interference and ensuring a certain quality-of-service (QoS) for both types of players. The EU-funded project ADEL aims to enhance the current LSA par-adigm by introducing 1) dynamic radio resource management (RRM), 2) sensing reasoning, based on database-assisted collabo-rative sensor networking, and 3) an extension to the LSA archi-tecture that allows a more effective RRM, increasing QoS satis-faction and policy enforcement for all players, finally leading to an overall improved spectrum utilization. The key features of ADEL's enhanced LSA paradigm are outlined throughout the remainder of this paper.