An opportunistic uplink scheduling scheme to achieve bandwidth fairness and delay for multiclass traffic in Wi-Max (IEEE 802.16) broadband wireless networks

We present a novel scheme for uplink scheduling in WiMax networks that attempts to balance worst-case fairness in bandwidth allocation with the delay requirements of multiclass traffic, while taking the varying nature of the wireless channel into account. We assume a polling mode of operation at the base station (BS), and provide an analytical technique for obtaining an optimal polling interval k at which the BS should poll the subscriber stations (SSs) to ensure that the delay requirements of traffic are met, while the relative unfairness in bandwidth allocation remains bounded. We also devise an opportunistic deficit round robin (O-DRR) scheme that schedules sessions by taking into account the variations in the wireless channel and the delay constraints of multiclass traffic. We demonstrate that our scheduler provides fairness in bandwidth allocation and robust delay guarantees, thus giving a provider a choice of balancing fairness with delay