Joint channel and power allocation in underlay multicast device-to-device communications

In this paper, we present a framework of resource allocations for multicast device-to-device (D2D) communications underlaying a cellular network. The objective is to maximize the sum throughput of active cellular users (CUs) and feasible D2D groups in a cell, while guaranteeing a certain level of the signal-to-interference-plus-noise ratio (SINR) for both the CUs and D2D groups. We formulate the problem of power and channel allocations as a mixed integer nonlinear programming (MINLP) problem where each D2D group can reuse the channel of at most one CU and each CU can share their resources with at most one D2D group. A maximum weight bipartite matching based scheme is developed to assign the optimal channel for each feasible D2D group to reuse. A heuristic algorithm is then proposed which has less complexity compared to the matching algorithm. The performance of both schemes is evaluated through simulations. Numerical results demonstrate that the proposed heuristic scheme outperforms other heuristic schemes in the literature and can achieve close-to-optimal performance.