Low-feedback cooperative opportunistic transmission for dynamic licensed shared access

In order to meet the exponentially growing capacity demands of future mobile radio communication systems, the synergy of spectrum sharing methods, multi-antenna transmission schemes, small-cell offloading, and cooperative communication techniques is suggested. In this context, the mitigation of harmful interference, the provision of quality of service (QoS) guarantees, and the minimization of backhaul and channel state information (CSI) overhead are key challenges that have to be addressed. In this paper, we study the performance of a Licensed Shared Access (LSA) system comprised of a macro-cell sector (incumbent operator) and three partially overlapping small cells (licensee operator) placed within that sector. The small cells utilize a new low-feedback cooperative opportunistic beamforming (OBF) with proportional fair scheduling (PFS) transmission scheme to ensure that the proposed system is able to reach the mentioned goals above. Simulation results show that this system attains a substantial fraction of the available sum-rate capacity with minimal feedback.