運作於OFDMA架構之WiMAX環境下以訊框為基礎的上鏈傳輸演算法

Frame-based Adaptive Uplink Scheduling Algorithm in OFDMA-based WiMAX Networks

黃志偉(Chih-Wei Huang)

指導教授 ： 黃依賢

元智大學/資訊學院/資訊工程學系/碩士(2009年)

https://doi.org/10.6838/YZU.2009.00336

摘要

本論文提出一個運作於正交分頻多重存取(OFDMA)架構下之全球微波互通存取介面(WiMAX)環境的上鏈傳輸演算法，由於上鏈排程器在設計上必須有效地處理固定和突發的資料流, 並且OFDMA實體層上的頻寬資源是以訊框為基礎的分配模式。因此, 我們提出的排程策略分別以一個長期和短期的思考觀點去計算Subscriber Station(SS)之所需頻寬，並以頻寬所需之權重進行剩餘頻寬的分配。 模擬的結果顯示本研究所提出之排程方法在平均延遲時間,抖動率及吞吐量上有較佳的效能表現。

關鍵字

全球微波互通存取介面 ； 正交分頻多重存取 ； 上鏈排程器 ； 服務質量

並列摘要

In this paper, we consider an uplink multiservice networks employing Orthogonal Frequency Division Multiple Access (OFDMA) for WiMAX networks. Since the OFDMA physical resource available for scheduling is frame by frame, the uplink scheduler located at base station (BS) must efficiently allocate available resources to the subscriber stations (SSs) in response to constant or bursty data traffic on a per-frame basis. In general, voice and video packets are generated periodically with fixed size packets (i.e. UGS) or periodic variable sizes packets due to coding technologies. Therefore, we propose a uplink scheduling strategy jointing bandwidth allocation and excess bandwidth compensation considering both short-term and long-term periods. Besides, this strategy grants the available resource for real-time and non-real-time traffics, called Frame-based Adaptive Bandwidth Allocation (FBABA) and Minimum Guarantee and Weight-based Bandwidth Allocation (MGWBA), respectively. Simulation results show our algorithm achieves QoS guaranteed, efficient resource allocation and high system throughput.

並列關鍵字

WiMAX ； OFDMA ； Uplink scheduling ； Frame-based ； QoS

參考文獻

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