超寬頻無線通訊系統之射頻接收機

Abstract

許多無線通訊標準於近年內已發展成熟，應用於戶外之無線通訊系統從第二代行動通訊發展至第四代行動通訊，資料傳輸流量從數百Kbps成長至數十Mbps。而應用於室內之無線通訊系統在藍芽系統與WiFi系統也已發展成熟，其資料傳輸流量也從數百Kbps發展至數百Mbps。應用於室內高速無線通訊系統，有可傳輸數百Mbps的超寬頻通訊系統(Ultra-wideband communication system)與數Gbps的無線高畫質傳輸系統(Wireless HD communication system)。 此博士論文提出一個可應用於3GH-11GHz超寬頻全頻段之射頻接收機前端電路，其中包含一低雜訊放大器與一降頻用混頻器。低雜訊放大器使用兩級增益補償以實現超寬頻特性與一帶通寬頻輸入阻抗匹配。降頻用混頻器使用主動式單端轉雙端訊號電路與主動式吉伯特混頻器(Gilbert mixer)。並提出一個可同時操作於3GHz-5GHz與7GHz-9GHz全球通用頻段之射頻接收機前端電路，其中包含一雙寬頻低雜訊放大器、一寬頻降頻用混頻器與一雙寬頻壓控震盪器。雙寬頻低雜訊放大器使用同時輸入並可切換式單一輸出技術，可將低雜訊放大器做最佳化設計。降頻用混頻器使用主動式單端轉雙端訊號電路與主動式吉伯特混頻器。雙寬頻壓控震盪器使用互補式負電阻負載，可同時輸出3GHz-5GHz與7GHz-9GHz之本地震盪器弦波訊號。此論文並提出一個可應用於57GHz-66GHz之微波接收機前端電路，其中包含一低雜訊放大器、一寬頻降頻用混頻器、一可變電感式壓控震盪器與一倍頻式壓控震盪器。低雜訊放大器使用多級增益補償以實現超寬頻特性。降頻用混頻器使用主動式吉伯特混頻器。可變電感式壓控震盪器使用變壓器來改變震盪器感值，借以改變震盪頻率。倍頻式壓控震盪器使用30GHz壓控震盪器與一頻率倍頻器，借以將壓控震盪器升頻至60GHz。本論文研製的寬頻無線通訊系統之射頻接收電路可提供此上述兩種室內高速無線傳輸系統接收機架構與電路。

In recent years, a numerous of wireless communication standards were developed. The outdoor network systems have been developed successfully from 2G cellular system to 4G cellular system. In the wireless wide area networks (WWANs), the throughput has been pushed from hundreds of Kbps to tens of Mbps. The indoor network systems have been developed in Bluetooth and WiFi. The throughput has been pushed to tens of Mbps. For hundreds of Mbps application, there are ultra-wideband communication systems. For several Gbps application, there is a wireless HD communication system. This dissertation proposes a RF receiver front end for 3GHz-11GHz all-band UWB application. The receiver front end includes a low-noise amplifier (LNA) and a down-conversion mixer. The LNA adopts a two-stage cascade amplifier to compensate power gain. The mixer uses an active single to differential balun and an active Gilbert mixer. A RF receiver front end for 3GHz-5GHz and 7GHz-9GHz worldwide UWB applications is also proposed. The RF receiver front end consists of a dual-input dual-wideband LNA, a down-conversion mixer, and a dual-wideband voltage-controlled oscillator (VCO). The dual-input dual-wideband LNA is designed for multi-input and single-output system. The mixer adopts an active single to differential balun and an active Gilbert mixer. The dual-wideband VCO utilizes the complementary cross-coupled negative-Gm structure. The dissertation also proposes a millimeter-wave receiver front end for 57GHz-66GHz wireless HD application. The receiver front-end includes a multi-stage LNA, a down-conversion mixer, a voltage-controlled inductor VCO, and a double frequency VCO (DF-VCO). The LNA adopts a multi-stage cascade amplifier. The mixer uses an active Gilbert mixer. The voltage-controlled inductor adopts a transformer to change the LC-tank inductance. The DF-VCO utilizes a cross-coupled VCO core and a frequency doubler.