IEEE 802.16標準是新一代的4G無線都會區域網路的協定，並且支援點對多點（point to multi-point）和網狀（mesh）網路。在網狀網路裡，依照資料排程的方式可以分為集中式（centralized）及分散式（distributed）這兩種排程方式。其中在分散式排程，允許節點與鄰近節點直接做通訊，每一節點以EBTT（election-based transmission timing）的競爭機制與二跳躍（2-hop）內的節點一起來對控制子訊框競爭傳輸時槽，並藉由所競爭到的傳輸時槽可透過MSH-DSCH訊息來傳送三向交握的資料內容，藉以完成資料連線的建立。但在IEEE 802.16標準沒有提出有關迷你時槽的配置方式，因此有效的排程方式便在分散式排程裡是一個重要的研究。
為了避免主要干擾（primary interference）及次要干擾（secondary interference）的影響，在本論文中，我們提出了三種方式來改善分散式排程在三向交握的過程所產生的問題，稱為啟發式迷你時槽配置（Heuristic Minislot Assignment；HMA）和部份同意方式（Partial Grant Scheme；PGS）和多重確認方式（Multiple Confirm Scheme；MCS），藉以提升網路的產能。經由模擬結果顯示，啟發式迷你時槽配置可以有效的避免主要與次要干擾問題，並降低迷你時槽配置的破碎比，增加空間利用率，部份同意方式可有效降低Grant階段所發生的無法配置問題，而多重確認方式則可有效降低Confirm階段所發生的頻寬浪費問題。

The IEEE 802.16 standard is a protocol for novel 4G wireless metropolitan area networks. In standard MAC protocol supports both of point-to-multipoint（PMP）and mesh mode. In mesh mode defines both of centralized and distributed scheduling. In distributed scheduling, allow direct communication between node and neighbor node, every node using election-based transmission timing mechanism to compete transmission opportunity on control subframe with two hops neighbors, and using MSH_DSCH message information to convey content of three-way handshaking on transmission opportunity, then establish data link will done. But in IEEE 802.16 standard does not proposal any minislot assignment mechanism, so effective scheduling will be important research on distributed scheduling.
For avoid primary interference and secondary interference issue, we propose three novel mechanism to improve relative issue in three-way handshaking period, that include the heuristic minislot assignment（HMA） and partial grant scheme（PGS） and multiple confirm scheme（MCS）. From simulation result, HMA can effective to avoid primary interference and secondary interference, and reduce fragmentation ratio for minislot assignment, increase the spatial reuse ratio. PGS can reduce assignment fail issue in Grant period. MCS can reduce bandwidth waste issue in Confirm period.

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