Distributed Resource Allocation With Local CSI Overhearing and Scheduling Prediction for OFDMA Heterogeneous Networks

摘要

We propose a resource allocation method for the downlink of an orthogonal-frequency-division-multiple-access (OFDMA)-based macrocell/femtocell overlaid heterogeneous network. To mitigate the interference caused by femtocell base stations (FBSs) on nearby macrocell users (MUs), conventional methods rely on the information of the interference channel states, as well as MU allocation mapping provided by a control channel, causing a substantial overhead increase. Instead, the proposed methods enable the FBS to predict the subchannels that are likely to be used by its neighbor MUs, based on their locally overheard channel state information, and to set appropriate constraints on those subchannels. Moreover, by letting the FBS fully reuse the subchannels estimated to be free from nearby MUs, the femtocell throughput is increased while scarcely degrading the macrocell throughput. The simulation results demonstrate the validity of our analysis for MUs' allocation estimation error probability and threshold optimization. Moreover, the proposed methods efficiently mitigate the interference from FBSs to nearby MUs, providing an excellent macrocell/femtocell throughput tradeoff, while drastically decreasing signaling overhead, compared with conventional methods.