Ying He, Dr., Lecturer of School of Computing and Communications, University of Technology Sydney

The wireless communication systems have dramatically changed the world by connecting people and devices in recent years. We are currently standing at the 4th generation (4G) in the evolution and drawing the picture for the next generation (5G) wireless communication systems. For which, we are aiming at 1000x increase of the capacity. Despite all efforts on the coding and modulation techniques, the growth of capacity is physically restricted by the limited spectrum resource. Therefore, spectrum sharing has been proposed to break this constraint. Our work on the current spectrum sharing frameworks includes two main spectrum sharing frameworks: Spectrum Access System (SAS) in U.S and Licensed Shared Access (LSA) in Europe. We address the common and differing factors then propose access and interference mitigation methods for SAS and LSA. SAS is a hierarchical access model with three tiers of users – incumbents, Priority Access Licensees (PAL) and General Authorised Access (GAA) users. We propose a PAL-GAA co-channel interference mitigation technique that does not expose base station locations. The distribution of the aggregated interference is derived using Probability Density Function and Characteristic Function. The optimal exclusion zone size is found through an approximation of a convex problem and our approach reduces the exclusion zone size substantially. We also propose the access and coexistence methods between different tiers in LSA and SAS.