Broadband Mixers for Microwave and Millimeter-wave Applications
Date Issued
2006
Date
2006
Author(s)
Chang, Fong-Cheng
DOI
en-US
Abstract
A mixer with good performance is indispensable in modern communication systems, which dominates the nonlinear effects of communication system. Therefore, to design a high frequency mixer with good performance is important.
The goal of the thesis is to design and implement wideband mixers in microwave and millimeter-wave regime. This research focuses on wideband mixer for applications in millimeter-wave region and UWB wireless system. The thesis can be divided into three parts. The first part introduces the basics of mixer as well as the designing parameters. In the second part, we start from the background of UWB system and then describe the regulations of UWB system. The advantages and drawbacks of traditional Gilbert cell mixer are investigated. Based on traditional Gilbert cell mixer, we proposed a folded-topology Gilbert cell mixer to reduce the dc power consumption. Further more, we employ the LC-ladder matching circuit to extend operating bandwidth. The final part of this thesis, two distributed mixer which can be used for applications in millimeter-wave region are implemented with 0.15-um GaAs pHEMT and 0.13-um CMOS technologies. The design concept is also described.
In this thesis, the folded-topology mixer was fabricated using TSMC 0.18-um CMOS technology. From the measured results, the double-balanced down-conversion mixer achieves a good conversion gain of 6-7 dB from 0.2 to 16.5 GHz with a low power consumption of 15 mW. The characteristics of low power consumption and wideband performance of the mixer are believed that the mixer is suitable for UWB wireless system applications. The chip size of the proposed mixer is 0.68 mm x 0.65 mm
The design of broadband down-conversion mixers in millimeter-wave is another focused point of this thesis. The distributed (or traveling-wave) concept is adopted to design a 4 to 41 GHz broadband down-conversion mixer. The measured results show that the mixer demonstrates a wideband performance from 4 to 41 GHz with a conversion gain of 3-8.5 dB. The simulations agree to the measured results. The dc power consumption is relatively low compared with previously published work. Another distributed mixer is implemented with TSMC 0.13-um CMOS. The mixer has a measured conversion gain of better than 0 dB from 2 to 50 GHz. Compared with published works, the mixer consumes the lowest dc power of 43 mW among the active broadband mixers in MMW regime. The chip size is 0.68 mm x 0.67 mm.
Subjects
混波器
毫米波
寬頻
射頻積體電路設計
互補式金屬氧化半導體
mixer
millimeter wave
broadband
RFIC
CMOS
GaAs pHEMT
Type
thesis