Uplink opportunistic spectrum sharing in LTE-A system with multiple indoor relays

With the increasing mobile traffic demands generated inside building, indoor relay is proposed for solving indoor dead spot and hot spot scenarios. This paper focuses on opportunistic spectrum sharing among indoor users (UEs) and outdoor users in the long term evolution-advanced (LTE-A) system without introduce significant interference to the primary transmissions. Three intelligent sharing schemes including indoor UEs sharing outdoor spectrum, indoor UEs inside different in-building coverage areas sharing spectrum with each other and outdoor UEs sharing indoor spectrum are proposed. Simulation results show that both indoor and outdoor uplink throughputs are tremendously improved compared to the no spectrum sharing scheme.