Multi-carrier waveform based flexible inter-operator spectrum sharing for 5G systems

This paper presents a multi-carrier waveform based inter-operator spectrum sharing concept for 5G mobile and wireless communication systems. The proposed concept considers the flexible air-interface being developed for 5G and can support coordinated inter-operator spectrum sharing in various scenarios, including mutual renting, spectrum spot market, co-primary sharing, licensed shared access (LSA), secondary horizontal sharing etc. Compared to state-of-the-arts, the proposed concept has much broader applicability and less restrictions on infrastructure conditions, including radio access network (RAN) sharing, inter-operator synchronization and fast inter-operator signaling. Furthermore, the proposed concept allows high flexibility both in spectrum allocation and adaptation of the transmission signals to support the large variety of devices expected in 5G scenarios. The key elements of the proposed concept includes the determination of a common subcarrier grid, a two-stage allocation procedure, fragmented spectrum usage, usage of “out-of-fragment radiation masks”, and adaptation of multi-carrier waveforms. Preliminary results have shown that the proposed concept allows efficient and flexible fragmented spectrum usage, with robustness against inter-operator synchronization mismatch.