Opportunistic Interference Management Increases the Capacity of Ad Hoc Networks

We introduce a new multiuser diversity concept with which multiple transmitters can communicate without causing significant interference to each other. The new scheme, called Opportunistic Interference Management (OIM), significantly reduces the feedback required in distributed Multiple-Input Multiple-Output (MIMO) systems, and requires an encoding and decoding complexity that is similar to that of point-to-point communications. We show that our proposed OIM scheme achieves a per-node throughput capacity of Θ (log(T(n))/√nT(n)) in a wireless network of n nodes and communication range of T(n) = Ω(√log n). This represents a gain of Θ (log(T(n))) compared to simple point-to-point communication. As such, OIM represents a practical alternative to attaining capacity gains similar to those attainable in theory with distributed MIMO systems, and opens up a new area of research for the development of medium access control protocols aimed at managing interference.