隨著車載設備的升級與網路需求的增加，車輛隨意網路已有許多相關研究，其中路側單元可用來改善車輛隨意網路的傳輸，亦可協助車輛連上網際網路，因此諸多學者提出不同且有效的佈署策略。然而近年來因行動網路普及，車輛已可透過行動裝置連接網路或透過周遭車輛分享的網路上網而無需使用路側單元。由於以往的策略沒有考慮車輛自主上網因素下佈署路側單元，可能因實際需求不如預期，導致佈署的路側單元效用不佳，造成資源浪費。
本研究提出RSU Placement with Maximal Internet Access(MIA)佈署策略來適應具上網車輛的車輛環境，試圖找出最多實際需要路側單元上網車輛的地區進行佈署，以提升整體的網路連通性。為找出各地區對路側單元的實際需求量，本研究首先透過區塊分割將地圖分為若干地區，並以上網車輛分享網路的覆蓋機率求出需求量，接著依照區塊內需求量多寡佈置路側單元。模擬結果證明，本研究提出的MIA方法，路側單元可較其他方法提升73%的上網車輛數，整體網路連通率則較其他方法提升12%。

With the upgrade of on-board equipments and the increase of network requirements, Vehicular Ad-hoc Network (VANET) has been studied for a few years. Road Side Unit (RSU) is not only used to improve network transmissions in VANET, but also help vehicles to access Internet. Thus, many RSU placement strategies have been proposed. However, nowadays some vehicles can access internet by mobile devices or networks shared by other vehicles, so these vehicles no longer need RSUs to connect Internet. Previous RSU deployment strategies did not consider the factor that some vehicles can directly access internet and will overestimate the number of vehicles requiring RSU. Therefore, the effect of deploying RSUs is not good, significantly wasting RSU resources.
The thesis proposes an approach, RSU Placement with Maximal Internet Access algorithm (MIA), to fit a vehicle environment where some internet accessible vehicles exist. MIA tries to find the maximal network requirements to deploy RSUs, so that it can improve the network connectivity. In order to find the amount of network requirements, MIA uses two phases. First, MIA divides the map into several small zones and uses the coverage probability of internet accessible vehicles to compute the number of network requirements. Second, RSUs are deployed in the center of the zones which have the maximal network requirements. Simulation results show that MIA can improve the number of vehicles accessing internet via RSUs about 73%, compared with others methods. For network connectivity, MIA can increase 12% than other methods.

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