Downlink Scheduling with Transmission Strategy Selection for Two-Cell MIMO Networks

Multiple-input multiple-output (MIMO) processing is a promising technique to achieve high speed data service in next generation cellular networks. However, the performance of multi-cell MIMO networks is limited by the cell-edge users who experience significant inter-cell interference. In this paper, we propose to use interference alignment to mitigate interference experienced by these cell-edge users, and spatial multiplexing for users with less interference. To achieve the optimal performance in a two- cell MIMO network, we formulate a joint scheduling problem to select a pair of users and the corresponding transmission strategies for both cells. We design an efficient dynamic scheduling scheme based on a stochastic network optimization framework. Numerical results show that the proposed scheme achieves a superior performance compared to scheduling schemes with a single transmission strategy.