Subchannel and power allocation for D2D communication in mmWave cellular networks

Abstract

This paper investigates resource allocation for device-to-device (D2D) communication in a millimeter wave (mmWave) cellular network where D2D users communicate in the cellular band. We formulate the optimization problem of subchannel and power allocation, which aims to maximize the sum rate of D2D transmitters while satisfying interference constraints at the base station (BS). Since the problem is NP-hard, solving it requires a huge amount of computation. Therefore we reduce its computational complexity by dividing it into two subproblems: a subchannel allocation problem and a power allocation problem. To solve the subchannel allocation problem, we propose two heuristic algorithms: the max greedy SNR scheme and the minimum interference scheme. The max greedy SNR scheme achieves higher sum rate and has lower computational complexity compared to the minimum interference scheme. However it requires global channel state information (CSI) of all nodes, which demands huge feedback overhead. On the other hand, the minimum interference scheme requires the location of each node. After subchannel allocation, the BS finds the optimal transmit power of each D2D transmitter by using the difference of convex (DC) programming. Simulation results verify that our proposed subchannel allocation schemes outperform the random subchannel allocation scheme, and the optimal power allocation results in the improved sum rate of D2D transmitters.