Predictive interference-based scheduling mechanism for direct communications in IEEE 802.16 networks

The point-to-multipoint (PMP) mode is considered a well-adopted transmission type that is supported by the IEEE 802.16 standard. The base station (BS) is served as a centralized coordinator to control and forward packets for mobile stations (MSs) within the network. With the consideration of direct communications, the required bandwidth and packet latency are reduced. However, the inappropriate arrangements of direct communications may introduce additional inter-cell interferences for other communications. In order to avoid this situation, a predictive interference-based scheduling (PIS) mechanism for each pair of MSs that are expected to conduct direct communication is proposed in this paper. Based on calculating the interference region and feasible region for the pair, the PIS mechanism properly arranges the MSs to conduct direct communication. The efficiency of the proposed PIS mechanism is evaluated and compared via simulations. Simulation studies show that the PIS approach efficiently enhances the performance of user throughput in comparison with the original adaptive point-to-point (APC) approach and the conventional IEEE 802.16 scheme.