Topological interference management for two cell interference broadcast channels with alternating connectivity

Topological interference management refers to the study of achievable rates within communication networks with no channel state information at the transmitter (CSIT) beyond knowledge of the network structure itself. In this work we consider the topological interference management problem within the context of a two cell two user interference broadcast channel (IBC) with alternating connectivity. Topological information, even though minimal, allows the transmitters to track the changing network structure and then exploit the varying connectivity states to obtain a degrees of freedom (DoF) gain. Thus, the main result of this work is the derivation of a novel outer bound on the DoF achievable by the two cell two user IBC in an alternating connectivity scenario. Additionally, we propose a scheme based on joint coding across states that achieves this outer bound for the case where all alternating connectivity states are equiprobable.