| Summary: | 碩士 === 國立中央大學 === 通訊工程研究所 === 98 === In order to response the developing of internet multimedia and application, Broadband Wireless Access (BWA) systems are also developed quickly. IEEE 802.16 WiMAX is one of the hottest new technologies in recent years. For the sake of serving different kinds of connections, IEEE 802.16 WiMAX classifies data connections into five types. These types are Unsolicited Grant Service (UGS), Real-time Polling Service (rtPS), Non-real-time Polling Service (nrtPS), and Best Effort (BE). Each type of connections has its own corresponding quality of service (QoS) parameters. In a WiMAX base station (BS), the scheduler is responsible for that which packet should be sent first and how the bandwidth would be allocated. Thus the network provider can change the scheduling algorithm in the scheduler according to policies. If a scheduler uses an improper scheduling algorithm, the scheduler may waste bandwidth or lower the quality of service of connections.
This thesis proposes a channel-aware QoS scheduler for IEEE 802.16 wireless metropolitan networks. This scheduler mainly considers WiMAX QoS parameter: the Maximum Latency. It is able to guarantee the Maximum Latency of rtPS connections. In addition to QoS parameter, the proposed scheduler also considers the channel condition of each connection and first serves the connections which have better channel condition. Thus the proposed scheduler can maximize the total throughput of the network. Simulation results also show that the proposed scheduler not only guarantees the QoS but also has better total network throughput than other schedulers.
|
|---|
