ITLinQ: A new approach for spectrum sharing in device-to-device communication systems

We consider the problem of spectrum sharing in device-to-device communication systems. Based on the recently-found condition for the optimality of treating interference as noise, we introduce the new notion of information-theoretic independent set (ITIS) which denotes a subset of users in a wireless network that are information-theoretically eligible to transmit data at the same time. This leads to our novel spectrum sharing scheme called information-theoretic link scheduling (ITLinQ) which at each time slot schedules the users in a single ITIS to transmit simultaneously. We perform a capacity analysis of ITLinQ and in a network model with a random placement of nodes in a cell, we characterize a lower bound on the fraction the information theoretic capacity region that it is able to achieve to within a gap. We will show that ITLinQ can outperform the conventional independent set scheduling by a multiplicative gain that scales with the number of users. We also present a distributed way of implementing ITLinQ and show that it yields a sum-rate gain of higher than 100% over similar state-of-the-art spectrum sharing mechanisms, such as FlashLinQ.