Utility Based Adaptive Scheduling Algorithm for Heterogeneous Services in Multiuser MIMO-Relay Systems

In this paper, heterogeneous services in multiuser multiple-input multiple-output (MIMO)-Relay systems are investigated, where the relays work in amplify-and-forward mode. A utility based adaptive scheduling algorithm is proposed, which aims to maximize user satisfaction as well as system spectral efficiency. Joint optimal carriers and spatial subchannels allocation is considered based on the proposed utility function, and two factors ratio and w are introduced in order to differentiate QoS and users. Moreover, a suboptimal solution is also presented for the sake of decreasing computational complexity and processing delay. Simulation results show that the proposed strategy can guarantee QoS of multiple services with a tolerable decline in terms of spectral efficiency compared with traditional maximum carrier/interference (MCI) algorithm. Besides, the complexity can be reduced obviously by utilizing the suboptimal scheme, which achieves nearly the same performance compared with the optimal solution.