在IEEE 802.16協調分散式（distributed）網狀網路中，定義了一個無碰撞的控制訊息傳送機制，稱之為EBTT（election-based transmission timing），而資料排程部份則是採用三向交握（three-way handshaking）的機制，然而在三向交握時，由於距離為二跳躍的節點無法知道彼此的排程資訊，而造成主要干擾（primary interference）以及次要干擾（secondary interference）等問題，使得迷你時槽（minislot）利用率降低。
因此本論文提出了一個預先決定之分散式排程機制（pre-decided distributed scheduling scheme；PDS）取代原本的EBTT機制，並且採用二路交握的機制來做資料排程，另外，在PDS機制中還提出了轉送排程訊息的機制，讓距離二跳躍的節點也可以收到排程訊息，在結合這些機制下，即可完全避免發生主要干擾以及次要干擾，來達到極高的迷你時槽利用率。從模擬結果可得知，本論文提出的機制確實有明顯的改善，由於所提出的方法不會有交握失敗的情況發生，所以除了在產能上有顯著的提昇外，封包延遲的部份也會有所改善，另外在公平性方面，本論文提出的機制也比IEEE 802.16標準要來的好。

IEEE 802.16 standard defines an election-based transmission timing(EBTT) scheme for coordinated distributed mesh network which can guarantee a collision-free environment for control subframe. And it use three-way handshaking mechanism for data scheduling. But three-way handshake mechanism has some problems such as the nodes which are two-hop neighbors cannot receive the schedule information. It causes the primary interference(PI) or the secondary interference(SI). The minislot utilization will be decreased.
In order to solve the above-mentioned problems, we proposed a pre-decided distributed scheduling scheme(PDS). And we also proposed a two-way handshake mechanism that is suitable for PDS. Finally, we proposed a mechanism to relay the schedule information. Let the nodes which are two-hop neighbors can receive the schedule information. After combining these three schemes, we can ensure to avoid PI and SI to achieve high minislot utilization. We compare our scheme and the IEEE 802.16 standard. The simulation results show our scheme improve the node throughput significantly. The average packet delay and fairness also better than IEEE 802.16 standard.

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