Admission Control and Interference-Aware Scheduling in Multi-hop WiMAX Networks

Multi-hop WiMAX networks based on IEEE 802.16 has the potential of easily providing high-speed wireless broadband access to areas with little or no existing wired infrastructure. WiMAX technology can be used as "last mile" broadband connections to deliver streaming audio or video to clients. Thus, quality of service (QoS) is very important for WiMAX networks. Providing QoS in multi-hop WiMAX networks such as WiMAX mesh or mobile multi-hop relay networks is challenging as multiple links can interfere with each other if they are scheduled at the same time. We propose efficient heuristic algorithms for scheduling flows in a centrally scheduled multi-hop WiMAX network. The proposed algorithms guarantee bandwidth and delay constraints of flows and allow multiple non-interfering links to be scheduled at the same time. We also define a "schedule efficiency" metric for comparing different flow scheduling algorithms. The simulation results show that the "schedule flow subchannel" algorithm leads to the best schedule efficiency.