Opportunistic beamforming for secondary users in licensed shared access networks

Licensed shared access (LSA) is a recently proposed concept for spectrum sharing which is based on authorized schemes of rights for secondary networks ensuring predictable performance to the incumbent network. In this paper, a secondary system (SS) employing an opportunistic beamforming technique with user scheduling is assumed to coexist with a primary system (PS). The proposed technique exploits the availability of PS information to SS offered by LSA, to serve the preferred SS user subject to the quality of service of the preferred PS user. In particular, for each generated beam per time slot, the multi-antenna SS base station decides whether to send data to the SS user with the maximum time-averaged rate request, depending on the quality of service requirement of the preferred PS user available in the LSA repository. Simulation performance results for a cellular channel model have shown that the proposed technique is capable of boosting the performance of the overall network.