Clustered Interference Alignment in Large Cellular Networks

Spatial interference alignment among a cluster of base stations is considered as a technique to mitigate inter-cell interference in the downlink of a large cellular network using OFDMA. We derive an expression for the mutual information achieved by clustered base station cooperation together with a zero-forcing receiver. Numerical performance results with throughput gains of up to 30% with respect to the non-cooperating base stations case are demonstrated for users located in the central area of the cells. Those results provide insight into the applicability of interference alignment methods in upcoming cellular networks.