ITLinQ: A new approach for spectrum sharing

We consider the problem of spectrum sharing in wireless communication networks composed of multiple source-destination pairs. We define a novel concept of information-theoretic independent sets (in short, ITIS) which indicates the sets of source-destination pairs in the network inside each of which, treating interference as noise is information-theoretically optimal (to within a constant gap). Then, we propose a new spectrum sharing scheme called information-theoretic link scheduling (in short, ITLinQ), which at each time schedules those users that form an ITIS. We first provide a performance guarantee of the ITLinQ scheme through characterizing the fraction of the capacity region that it can achieve in a network with source and destination nodes spread randomly in a fixed area. Moreover, we will show how to implement the ITLinQ scheme in a distributed fashion by using an initial 2-phase signaling mechanism which provides the required channel state information at all the nodes. Finally, we compare the performance of the distributed ITLinQ scheme with similar state-of-the-art spectrum sharing mechanisms, such as FlashLinQ, through numerical analysis and show that it can exhibit a sum-rate gain of more than a 100%, while keeping the complexity at the same level.