Opportunistic Interference Alignment and Cancellation for the Uplink of Cellular Networks

In this letter, we propose an opportunistic interference alignment and cancellation (OIAC) scheme for cellular networks to exploit the multi-user diversity gain and the backhual resources among base stations. Particularly, an opportunistic user scheduling strategy is proposed by synthesizing opportunistic interference alignment (OIA) and successive interference cancellation (SIC). In the OIAC scheme, we propose a new user scheduling metric and a sequential user selection scheme based on the characteristics of SIC, and guarantee a target signal-to-interference-plus-noise ratio (SINR) for each selected user by performing user selection, decoder design and power control jointly in the user selection process. The OIAC scheme improves system performance by using SIC and keeps the low implementation complexity property of OIA. The simulation results show that the OIAC scheme can improve the achievable sum rate significantly compared to OIA and other schemes.