DTMR: delay-aware traffic admission, mode selection, and resource allocation for D2D communication

Abstract

In device-to-device (D2D) communication underlaying a cellular network, the resource control involves traffic admission, mode selection, orthogonal channel assignment, and power control. Traffic admission limits queueing delay, mode selection exploits the proximity gain, and resource allocation guarantees user performance. Jointly optimizing these factors is highly challenging due to the stochastic nature of the system and the coupled control actions. Many previous works only consider a subset of these factors. In this paper, we tackle the joint optimization problem for delay-aware D2D communication. In particular, considering both dynamic traffic arrival and time-varying channel fading, we aim to maximize the time-average sum-rate of the network subject to the time-average throughput guarantee of users and resource allocation constraints. Thus, through presenting a Lyapunov optimization framework, we design an optimal delay-aware traffic admission, mode selection, and resource allocation (DTMR) strategy with polynomial time complexity based on dual optimization and ellipsoid search. We also analytically derive lower bound of the time-average sum-rate achieved by the proposed DTMR strategy. Further, we develop a fast heuristic strategy by decoupling the binary constraints of mode selection and channel assignment. Finally, simulation results demonstrate the superiority of the DTMR strategy against alternative strategies.