Wi-Fi Direct（WFD）為基於Wi-Fi技術的協定，旨在實現設備到設備（D2D）通訊，現今被廣泛地應用於移動裝置中。雖然裝置間可以透過WFD直接進行通訊，但一個WFD群組的通訊範圍會受到物理層的限制。同時利用WFD介面和Wi-Fi介面，可以形成多重跳躍的WFD群組的網絡。雖然藉由這個方式可以擴大通訊範圍，但是多重跳躍的WFD網絡將遇到群組之間的通訊問題。在本文中，我們提出一種多跳WFD網絡及一種通訊方案來實現群組間的直接通訊。我們亦分析了相關研究並論述了它們的不足之處。此外，我們提出了一種自主性方案，允許我們的網絡自動形成並動態運作。最後，我們設計了一個服務導向的中介軟體，它在現成的Android設備上運行我們的網絡方案。為了使我們的可被重複利用，我們為開發人員提供應用程式介面（API）。他們可以在我們的網路上實作自己的應用程式。而在實驗結果中，我們評估了我們方案形成網絡的延遲。

Based on Wi-Fi technology, Wi-Fi Direct (WFD), which is widely equipped on mobile devices, aims at Device-to-Device (D2D) communication. Although devices can communication directly through WFD, the communication range of a WFD group is restricted by the physical layer. Exploiting both WFD interface and Wi-Fi interface simultaneously, a network with multi-hop WFD groups can be formed. Although the communication range can be enlarged, a multi-hop WFD network will encounter inter-group communication problems. In this thesis, we propose a multi-hop WFD network with a communication scheme to make inter-group communication direct. We also analyze the related works and point out their shortcomings. Moreover, we propose an autonomous scheme which allows our network to form autonomously and work dynamically. Finally, we design a service-oriented middleware which runs our network schemes on o-the-shelf Android devices. For reusability, we also provide Application Programming Interfaces (APIs) for developers to implement applications over our network. In the experimental results, we evaluate the latencies of our schemes to form a network.

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