近年來在行動任意網路中使用指向性天線作通訊已經越來越普及。因為能節省頻寬與能源的消耗，目前已經有許多使用指向性天線達成廣播與繞路機制的研究被提出。然而，大部分的研究均著重在哪些網路節點需要朝向哪些方向來跟其他節點通訊。本篇論文提出了一個在行動任意網路中使用指向性旋轉天線達成排程的廣播機制。當網路上某一個移動節點在短時間內收到多個封包時，它會為每一個封包安排傳送的順序來減少多餘的天線轉動以及封包傳送延遲時間。主要的方式是如果多個儲存在封包佇列的封包都需要朝向其中一個方向進行傳送，那麼這些封包會連續的朝此方向傳送，之後天線再轉至下一個方向進行傳送。模擬結果顯示本方法在封包傳送延遲時間與天線平均旋轉圈數上，均比無使用排程機制來的好，且仍然能維持一樣高的封包傳送率。

In recent years, using directional antennas for communication in mobile ad hoc networks is becoming popular. Because of conserving bandwidth and energy consumption, there have been many researches about broadcasting or routing using directional antennas proposed now. However, most of them focus on deciding which nodes should communicate with others in which directions. This thesis proposes a scheduled broadcasting method with rotational single beam antennas in mobile ad hoc networks. When one mobile node receives multiple packets and wants to rebroadcast them out within short time, it schedules the retransmission sequence of each packet to reduce the unnec-
essary rotations of its antenna and overall end-to-end transmission delay. The basic idea is that packets stored in one node's packet queue will be sent out in a certain direction successively if this direction is one of these packets' broadcasting directions. Then the antenna rotates to next direction for next transmission. The simulation results demonstrate that the proposed method outperforms the non-scheduled one in terms of the end-to-end packet transmission delay and the average rotations of antennas, while it can still maintain high packet delivery ratio.

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