Leveraging Physical-Layer Capabilites: Distributed Scheduling in Interference Networks with Local Views

In most wireless networks, nodes have only limited local information about the state of the network, which includes connectivity and channel state information. With limited local information about the network, each node's knowledge is mismatched; therefore, they must make distributed decisions. In this paper, we pose the following question: If every node has network state information only about a small neighborhood, how and when should nodes choose to transmit? While link scheduling answers the above question for point-to-point physical layers that are designed for an interference-avoidance paradigm, we look for answers in cases when interference can be embraced by advanced PHY-layer design, as suggested by results in network information theory. To make progress on this challenging problem, we propose a constructive distributed algorithm that achieves rates higher than link scheduling based on interference avoidance, especially if each node knows more than one hop of network state information. We compare our new aggressive algorithm to a conservative algorithm we have presented in a 2013 conference paper. Both algorithms schedule subnetworks such that each subnetwork can employ advanced interference-embracing coding schemes to achieve higher rates. Our innovation is in the identification, selection, and scheduling of subnetworks, especially when subnetworks are larger than a single link.