雙頻帶威福-哈特利鏡像消除接收機與超寬頻LR-CR正交相位降頻器

Abstract

本篇論文為因應現今無線通訊的應用，故分別設計應用在兩種常見通訊系統的射頻電路。第一種應用是結合低雜訊放大器以及具有鏡像消除功能的威福-哈特利複數降頻器而成的接收機；由於無線通訊網路的蓬勃發展，將此接收機設為雙頻帶，並配合低中頻架構以避開閃爍雜訊的影響。而為了製作成本的考量，利用TSMC 0.18um CMOS製程來實現此鏡像消除機收機，並由量測結果發現，此接收機在兩個頻帶中都能有超過50dB以上的鏡像消除比率。 第二種應用則是利用一個新式的正交相位產生器，配合馬爾尚巴倫的寬頻特性，製作了一個可以適用於超寬頻系統的正交相位降頻器。由於TSMC 0.35um SiGe HBT元件的截止頻率較TSMC 0.18um CMOS元件高，故將其用來製作超寬頻正交相位降頻器，並在輸出兩埠測得兩正交訊號的相位誤差低於2°，且輸出振幅誤差不超過1dB。

This thesis is divided into two parts. One part realizes a single-chip dual-band Weaver-Hartley receiver with high image rejection ratio for the Wireless LAN RF front-end. In order to lower the cost of the receiver, we choose a TSMC 0.18um CMOS technology to achieve a Weaver-Hartley image rejection receiver with a more than 50dB image rejection ratio for each band. The other part demonstrates a novel quadrature generator. Because the TSMC 0.35um SiGe HBT transistor has a higher cut-off frequency than the TSMC 0.18um CMOS transistor, the UWB I/Q down-converter is fulfilled in a TSMC 0.35um SiGe BiCMOS technology. With the wide bandwidth of the Marchand balun, the UWB I/Q down-converter whose IF I/Q outputs achieve an amplitude imbalance of < 1dB and a phase error of < 2° is realized for UWB applications.