Successive interference cancellation in downlink cooperative cellular networks

This work studies the improvement in the sum rate of downlink cellular networks using successive interference cancellation (SIC). First, we consider a two-cell cellular network and propose a cooperative SIC scheme, in which one user receives its data at the single-user capacity using SIC while the rate in the other cell is appropriately adapted to maximize the sum rate. Identifying the corner points of the rate region of a two-user interference channel, we derive conditions for which applying SIC increases the sum rate as compared to treating interference as noise (IaN). Conditions when both mobiles can perform SIC are also given. These conditions allow us to identify cell areas and user positions in which SIC gains can be achieved. Furthermore, a flexible user association policy is presented as a means to further increase the sum-rate gains by using SIC. Finally, we propose a centralized cell scheduling for performing cooperative SIC in multiuser multi-cell networks. Numerical results show that significant sum-rate improvement is achieved using SIC receivers, even with few users per cell and especially at the cell edge.