IEEE 802.11 無線區域網路(Wireless Local Area Networks, WLAN)是目前國內通訊領域最重要的一項產業，不只相關系統出貨量已為全球首位，並且數家IC 設計公司也推出其核心IC 晶片組，完成國內上、下游產業及技術之整合。不過，802.11 系統因使用頻帶(2.4G 或5.2G 頻段)，通訊環境(通常為室內)及傳送功率等限制，使用上最令人詬病的是其傳送距離(Access Point 及用戶間)及傳輸可靠性(影響實際傳送datarate)等問題。
　　本論文的目的即針對 IEEE 802.11 a/b/g 系統，研究開發可延伸接取點(AccessPoint，AP)及用戶(Station, STA)間通訊距離並提高通訊品質的技術及系統設計。本論文引進無線橋接器(Wireless Bridge , WB)作為AP 及STA 間之中繼(Repeater)，其功效不祇AP 涵蓋範圍之延伸，並可因STA 與WB 或AP 間距離縮短而提高接收訊號品質，降低干擾，而獲致整體頻譜效益及系統傳輸容量的提升。而本論文所設計的WB 以符合802.11 standard 為基礎，以減少對現有WLAN 系統(標準)的影響。

　　Nowadays, IEEE 802.11 wireless local area networks (WLAN) related product plays an important role in the domestic communication industry. Not only its productive quantity occupies the first place in the global trade market, but also several local IC design houses have announced to provide the key IC components. It means local industry can take the great advantage of an integration of top to down level technologies in the manufacture of WLAN systems. However, WLAN systems usually offer a low hroughput due to the problems of long transmission distance and poor communication reliability.
　　The purpose of this paper is to study and develop a way to solve the problems and to improve the system throughput. The idea is to introduce a new device, called Wireless Bridge (WB), as the repeater between Access Point (AP) and Stations (STA). The benefits we can get from such design are extension of AP coverage, improvement of spectrum efficiency and system throughput due to shortening the communication distance, etc. This paper also aims to a complete solution which shall have less effect on the existing 802.11 standard as possible.

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