於智慧行動裝置建立具備重傳機制之可見光通訊系統

Visible Light Communication System with ARQ Applied to Smart Mobile Device

陳則安(ZE-AN CHEN)

指導教授 ： 李昌明

國立中正大學/工學院/通訊工程學系/碩士(2016年)

摘要

近來數據傳輸在日常生活中已是一項不可或缺的技術，在無線通訊技術有所精進時，其附屬功能的元件也日益增加，而近期興起之智慧型行動裝置的相關應用更為常見，舉凡檔案傳送與多媒體串流服務皆有其可發揮之處。不過隨著行動裝置的普及，傳輸環境的限制也逐漸浮現，特別是電磁干擾與無線電波頻譜不足都會限制行動裝置的應用，本研究將考量以現有智慧行動裝置的硬體元件建構無線可見光的通訊系統以彌補現有無線電波傳輸不足之處，希望能進一步提升傳輸率與整合現有的軟硬體資源，若能在不增加硬體成本的要求下完成此系統的開發，不但可提升智慧行動裝置的附加價值，也有利於相關產品的推廣與後續技術的延伸。
本論文的研究方向，以不增加硬體成本為主要考量達到傳輸的目的，主要分為兩大階段進行，第一階段，先基於QR Code (ISO/IEC 18004) 建構一對一的LED-Camera VLC單向傳輸系統，利用行動裝置間的螢幕顯示器與相機鏡頭來做檔案傳輸，傳輸速率可達39.84Kbps；第二階段，建構一對一具備重傳機制的LED-Camera VLC單向傳輸系統，將第一階段加以延伸利用，將行動裝置之間以面對面的方式對齊位置，再利用各自行動裝置間的螢幕顯示器與前鏡頭，發送與接收訊息，如傳輸過程有誤時，將回傳資訊，直到所有資料傳送完畢，達到傳輸完整性的目的，傳輸速率為5.88Kbps。

關鍵字

重傳機制 ； QR碼 ； LED-Camera光通訊系統

並列摘要

Recently, data transmission has become more important in our daily life. Especially, the smart mobile device is used frequently to support the file transfer and multimedia streaming services with wireless communication technologies. Moreover, the developments of communication component are diverging with electromagnetic (EM) techniques. According to the popularity of wireless communications, the limitations of transmission also appear. Especially, electromagnetic interference and frequency spectrum shortage would limit the application of wireless communication in mobile devices. To overcome these issues with existing equipment, we consider the wireless visible light communication (VLC) system over mobile device with LED display and digital cameras. The value of mobile device can be increased, while the robust and efficient VLC is developed without additional hardware cost.
We fulfill a robust VLC system in the mobile device with two stages. First, LED-Camera VLC communication systems based on QR Code (ISO/IEC18004) are realized with screen and (front and rear) cameras. The transmission rate would be 39.84 kbps. Second, LED-Camera VLC system with ARQ is realized with LED screen and front camera. The repeat request would be active (sent by the receiver) while the data transmission is unsuccessful. The transmission rate is up to 5.88kbps in our experiment
In the future, integration of system libraries and SDK can increase the successful transmission rate. Second, more transmission modes would be considered such as broadcast mode and bidirectional communication system.

並列關鍵字

ARQ ； QR Code ； LED-Camera VLC

參考文獻

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