System-level performance of interference alignment

This paper presents analytical expressions that enable quantifying the spectral efficiency of antenna-domain IA (interference alignment) in cellular networks. From these expressions, the benefits of such IA are characterized. Under rather favorable assumptions, IA is found to be beneficial only in very specific and relatively infrequent network situations, and a blanket utilization of IA is altogether detrimental. Applied only in the appropriate situations, IA does bring about benefits that are significant for the users involved but small in terms of average spectral efficiency for the entire network.