Maximum clique-based resource allocation in device-to-device communications

Device-to-Device communication (D2D) integrated in cellular networks emerges as a new trend in response to notable rise in traffic demand. Resource allocation is one of the important challenges in deployment of D2D networks. In this paper, we formulate an optimization problem for optimal resource allocation and then propose a novel algorithm namely maximum clique based resource allocation (MCRA) for improving the spectral reuse based on graph theoretic concept of maximum clique. Practical application of D2D communications requires each node to receive and transmit signals during the communication process. We have considered this issue in constructing the interference graph and mathematical formulations in our system model. We have proposed an efficient algorithm called binary code-based maximum clique detector (BCMD) to find the maximum clique solution with reduced complexity in interference graphs. Finally, to mitigate the overall interference and complexity of the problem, a two level resource allocation algorithm (TLRA) is suggested. The results demonstrate that substantial gains are achieved in terms of sum rate, time and computational complexity compared to the existing approaches in literature.