近年來，越來越多研究學者開始研究探討如何在緊急急難現場提供緊急通訊的服務，在本論文中我們使用Wi-Fi Direct技術來達到可靠地通訊之目的，根據Wi-Fi Direct的規範，裝置需要加入一個Group才得以與其他裝置進行通訊，然而這樣子的通訊方式並不適用於災難現場的通訊，因為容易造成時間上的浪費以及能量的消耗，因此在本論文中，我們提出無須連接至群組的Wi-Fi Direct通訊方法來達成緊急通訊之需求，在所提出之方法中，我們額外設計了封包遺失處理程序來保證通訊的可靠性，以及兩種省電機制來減少裝置能量的消耗，以藉此延長裝置存活時間。我們的實驗與實做結果顯示，所提出之方法能快速且可靠的傳遞資訊，且達到電量節省之特性。

Recently, more and more researchers have investigated how to provide emergency communication services in scenes. In this work, we propose to use Wi-Fi Direct technology to achieve reliable communication in such scenarios. According to the Wi-Fi Direct specification, a device needs to join a group before starting communicating with other devices. However, this policy will cause the waste of time and energy consumption on communications. In this paper, we proposed a connection-less scheme to achieve emergency communication by Wi-Fi Direct. In the proposed method, we also design a packet loss handling procedure to ensure the reliability of communication, as well as two power-saving mechanisms to reduce the energy of the devices. Our experimental and simulation results show that the proposed method can quickly and reliably transmit information and achieve energy savings.

目錄
第一章 簡介	1
第二章 相關研究	6
2.1 Wi-Fi Direct規範簡介	6
2.2相關文獻	11
第三章 網路架構	14
第四章 所提出之方法	18
4.1網路組成與資料傳輸	18
4.2省電機制	21
4.2.1 Slot-based	21
4.2.2 Column-based	23
第五章 系統實作	27
5.1 Android Wi-fi Direct 實做	27
5.2 無修改原始碼版本實做	39
第六章 效能評估	41
6.1實際實驗	42
6.1.1傳輸耗時	42
6.1.2省電效率	43
6.1.3封包遺失	44
6.2 模擬實驗	46
第七章 結論	48
參考文獻	49
附錄-英文論文 52
 
圖目錄
圖1：Wi-Fi Direct網路情境	3
圖2：Device Discovery流程圖	8
圖3：GO Negotiation 流程圖	10
圖4：群組配置圖	10
圖5：網路樹狀結構圖	14
圖6：Slot-based之救援裝置示意圖	22
圖7：Slot-based之末端裝置示意圖	23
圖8：Slot-based之中繼裝置示意圖	23
圖9：Quorum-based之救援裝置示意圖	24
圖10：Quorum-based之末端裝置示意圖	25
圖11：Quorum-based之中繼裝置示意圖	26
圖12：實作架構圖	28
圖13：通訊示意圖	33
圖14：Byte限制示意圖	35
圖15：Data欄位範例	36
圖16：Total / Now欄位範例	36
圖17：實際執行畫面	38
圖18：傳輸耗時	43
圖19：不同狀態下的耗電程度	44
圖20：傳輸間隔時間對封包傳輸成功率的影響	45
圖21：在不同通訊範圍與封包遺失率下所花費的週期	47


表目錄
表1：Probe Request封包的Device Name	34
表2：Probe Response封包的Device Name	34
表3：有無進行修改原始碼的優劣差異性	40
表4：模擬環境參數	41

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[13]	Bluetooth. https://www.bluetooth.com/
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[15]	Bonjour. http://developer.apple.com/networking/bonjour/index.html.
[16]	Universal Plug and Play(UPnP). http://www.upnp.org.
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[18]	Android Open Source Project(AOSP). https://source.android.com/
[19]	Android 6.0(Marshmallow). https://www.android.com/versions/marshmallow-6-0/
[20]	Nexus 7. https://www.google.com.tw/intl/zh-TW_tw/nexus/
[21]	Wi-Fi Direct Framework. https://w1.fi/wpa_supplicant/