臺灣大學: 電子工程學研究所呂良鴻何姿誼Ho, Tzu-YiTzu-YiHo2013-04-102018-07-102013-04-102018-07-102011http://ntur.lib.ntu.edu.tw//handle/246246/256808隨著無線技術的迅速發展與普及，現今人們對資料傳輸需求量日益增大。無線區域網路由於能夠隨時隨地提供即時的多媒體傳輸服務，因此受到相當大的關注。因此，現今的研究著重於在各式各樣不同的使用環境中，提供良好的傳輸品質。 為了建立更加可靠與穩健的無線通訊連結，在本論文中，提出兩種自動增益控制迴路以擴展接收器的動態範圍。在第三章節中，功率偵測器引入了偏移抵消技巧，使得低雜訊放大器的增益能夠適應性地切換，因而進一步地避免了射頻前端電路進入操作飽和。第四章節中，以所提出之可程式化增益放大器為基礎，建構了一個具有自動增益調整功能之寬頻可程式化放大器，而此寬頻操作適用於現今與未來不斷拓展頻寬的無線區域網路規格。With the rapid development and popularization of wireless technology, nowadays people show ever-increasing demand for mass data transmission. Among all wireless local area network (WLAN) technology has attracted most attention due to the capability of real-time multimedia sharing anywhere anytime. Therefore, it is desirable to provide an excellent service quality for various environments. In this thesis, in order to build up a more a reliable and robust wireless link, two architectures of automatic gain control (AGC) loop at both RF front-end and baseband are proposed for extending the dynamic range of the receiver. In Chapter 3, a power detector with offset cancellation is introduced for determining the gain mode of variable-gain low-noise amplifier. The gain selection mechanism prevents RF front-end circuits from operating in saturation. In Chapter 4, based on the proposed programmable gain amplifier gain (PGA) cell, a wide-bandwidth PGA with AGC function is constructed. The wideband operation meets the requirement of expanding channel bandwidth in new/ongoing WLAN standards.1979104 bytesapplication/pdfen-US自動增益控制低雜訊放大器功率偵測器增益可程式化放大器無線區域網路Auto gain control (AGC)low noise amplifier (LNA)power detectorprogrammable gain amplifier (PGA)WLANthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/256808/1/ntu-100-R97943137-1.pdf