An efficient uplink scheduling mechanism with enabling Multi-device Transmission and Maximum Latency Fulfillment in IEEE 802.16j networks

IEEE 802.16j spreads out the coverage of the WiMAX network via extending the signal transmission by using the relay technology. To take the advantage of relaying in IEEE 802.16j network, an efficient schedule with quality of service (QoS) provision for multiple link transmissions is necessary, especially when link interference exists. In this paper, we propose an uplink scheduling mechanism with enabling Multi-device Transmission and Maximum Latency Fulfillment (MT-MLF). In the mechanism of MT-MLF, an interference detection mechanism is first carried out, then a resource distribution algorithm and a dynamic frame adjustment method are developed. Through the adoption of the proposed scheduler, both the uplink resource utilization and the requirement of real time applications can be better enhanced. Two simulation experiments were conducted with different levels of interference. The results demonstrate that under a fixed QoS type of connections, when the total number of connections goes up to 360 and 420 and the maximum latency violation rate approaches 20%, the average uplink transmission rate of MT-MLF can achieve 6.67Mbps and 7.92Mbps, which apparently outperform 4Mbps and 3.91Mbps as compared with regular relay scheduling schemes.