Multi-carrier cooperated interference cancelation in heterogeneous cellular networks

With the increasing number of mobile terminals, the capacity of cellular network can hardly satisfy the user requirement in the future. In next generation cellular systems, heterogeneous network is proposed to improve the spatial spectrum efficiency. In this paper, we study a joint coding scheme to increase the achievable sum-rate of multi-carrier heterogeneous systems, where we introduce transmission cooperation among subcarriers in the amplitude space to assist interference elimination at the receiver. Specifically, we propose to transmit information through cross links on some of the subcarriers where the users suffer from the strong interference, and use this information at the receiver to cancel the interference experienced on other subcarriers. We develop the direct-link transmission strategy using layered lattice code, and design subcarrier allocation algorithm between direct-link and cross-link transmissions. Simulation results show that the proposed joint coding scheme achieves higher sum rate than separated coding schemes in strong interference channels.