全球互通微波存取(Worldwide Interoperability for Microwave Access; WiMAX)，是無線通訊方法之一，可以提供寬頻網路於大規模的覆蓋範圍。WiMAX使用了IEEE-802.16的標準。為了提供有服務品質(Quality of Service; QoS)的服務，服務流被分為五種類別。IEEE-802.16標準並沒有為服務流定義排程演算法，也沒有為基地台之輪詢定義一個有效的管理機制。輪詢是一種傳送機制，在傳輸資料前，使基地台(Base Station; BS)進行輪流詢問,被詢問的用戶端工作站(Subscriber Station; SS)才可以傳送頻寬要求訊息。
本論文中，我們提出一個上行輪詢法稱作可附掛的頻寬需求輪詢法(polling according to the piggyback capable bandwidth request; PAPCBR)。當用戶端工作站被輪詢(Polling)，且此時有資料要做傳送，用戶端工作站會傳送頻寬要求給基地台。當基地台收到頻寬要求時，會根據頻寬需求來調整輪詢間隔(Polling Interval)。除此之外，當即時輪詢服務流被輪詢時，若非即時輪詢服務流有頻寬要求，也可附掛上頻寬要求，如此，基地台分配頻寬給即時輪詢服務流後，若有剩餘頻寬，則將分配給非即時輪詢服務流之頻寬要求。模擬結果顯示是比沒有附掛要求的方式要好。

Worldwide Interoperability for Microwave Access (WiMAX) is a developing wireless communication scheme that can provide broadband access to large-scale coverage. WiMAX is a network using the family of standards of IEEE-802.16. To ensure the Quality of Service (QoS) , the service flows are classified into five classes. The standard of IEEE 802.16 does not define the scheduling algorithm for the service classes and also does not define an efficient mechanism for the polling management of the base station (BS). Polling is a mechanism with which the subscribe station (SS) can send bandwidth request without collision. The BS polls the SSs and the polled SSs can send their bandwidth requests according to the directions in ULMAP of the frame.
In this paper, an polling algorithm named polling according to the piggyback capable bandwidth request(PAPCBR) for WiMAX networks is proposed. When SS is polled and has data to send, it will send bandwidth request to BS. Then, BS will adjust polling interval according to this bandwidth request. Furthermore, if the service flow of rtPS has been polled, the service flow of nrtPS can piggyback its request on the bandwidth request of rtPS. The simulation shows the result is better than that without piggyback.

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