伴隨著物聯網，車聯網的日益發展快速，在這其中因ARM架構處理器的省電低功耗，低成本及SoC(system on a chip)強大的周邊I/O應用整合，可輕易將許多sensor與device集成在一起，這也使得client端ARM處理器架構的系統越來越普及，功能越來多元，而Android系統便是其中備受廣泛應用的系統之一，也因其可高度客制化與open source的關係，使其中發展至今已由手機延伸到車載電子。
而車載電子因其特殊的使用環境而無法持續穩定的供電，例如在汽車引擎熄火後所有電子裝置只能由電瓶供電，所以大部分車載電子為了減少電力消耗會切換系統狀態至省電模式或切斷電源，等待引擎發動時再切換回原本的工作模式，因此如何縮短車載Android系統在狀態切換所消耗的時間就成了一個很重要的solution。
快速啟動技術主要根據嵌入式系統之特性，透過優化系統的資料傳輸與刪除不必要初始步驟，使系統更能以最短的時間進入工作狀態，本研究將以現存的加速技術中，最佳化適合目前Android系統架構之技術，經實驗測試，優化後的效能相較優化前減少了50%的啟動時間。

關鍵字：Android系統、Fast booting、U-Boot、Linux Kernel、Filesystem
 

Due to the Internet of Things, the Internet of Vehicles is growing rapidly. Among them, because of the power-saving and low power consumption of ARM-based processors, the low cost, and the powerful SoC (System on a chip) can easily merge the peripheral I/O applications, it is easy to integrate many sensors and devices to be integrated together, and makes the client-side ARM processor architecture system more and more popular, and the functions are more and more diverse, so Android system is one of the most widely used systems because it can be highly customized and open source so that it extended the development from mobile phones to vehicle electronics.
However, due to its special use environment, vehicle electronics cannot continuously and stably supply power. For example, all electronic devices can only be powered by batteries after the car engine is turned off. Therefore, in order to reduce power consumption, most vehicle electronics will switch the system state to the power saving mode or Turn off the power and wait for the engine to start before switching back to the original working model. Therefore, how to shorten the time consumed by the embedded Android system during state switching has become an important solution.
The quick-start technology is mainly based on the embedded system's characteristic, by optimizing the system's data transmission and deleting unnecessary initial step so that the system can enter the working state in the shortest time. This study will use the existing acceleration technology to optimize the suitability the technology of the current Android system architecture, after experimental testing, the optimized performance reduces the startup time by 50% compared with before the optimization.
Keyword: Android system、Fast booting、U-Boot、Linux Kernel、Filesystem
 

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