【作者】 徐洪波；

【导师】 陈向东；

【作者基本信息】 西南交通大学 ， 电路与系统， 2010， 硕士

【摘要】 近年来,无线通讯和CMOS工艺得到了很大发展,射频集成电路可以用CMOS工艺来实现。在各种无线通讯新技术中,超宽带技术(Ultra-Wide Band,UWB)以其高速率、低功耗的特点受到无线通讯学术界的广泛重视,是一种具有巨大发展潜力的新技术。低噪声放大器是无线接收机的第一级,其良好性能保证了射频前端的正常工作。研究基于CMOS工艺的超宽带低噪声放大器,具有重要理论与实践意义。本文首先对超宽带低噪声放大器的研究现状和CMOS集成电路的特点作了论述。其次,分析了几种常见的输入匹配电路,比较了各电路的优缺点,研究设计了巴特沃斯滤波器作为输入匹配电路。共源共栅结构具有增益大,密勒效应小,结构简单等优点,本文决定将其作为电路主放大结构,然后用基于功耗限制的噪声优化理论推导出了输入MOS管的最优尺寸,并采用级间匹配结构来提高增益降低噪声。为满足宽带需要,电路设计采用了电容耦合负载电路。本文还分别设计了电压偏置电路和电流源电路,以促进低噪声放大器的性能最优化。超宽带低噪声放大器的电源电压为1.5V,采用台积电0.18μmCMOS工艺。用ADS2008软件进行仿真,仿真结果显示：在3～5GHz带宽内,噪声系数低于2.3dB,增益大于12dB,最大增益大于14dB,增益波动小于2.4dB,一分贝压缩点约为-15dBm。输入输出匹配均优于-10dB,功耗为19mW。更多还原

【Abstract】 With the rapid development of wireless communication technology and CMOS process in recent years, RFIC can be achieved by CMOS process.One of new wireless communication techniques is UWB, which people from wirless communication academe attach great importance to,because of its high data speed and low power consumption. So UWB can be considered as a new huge development potential technology. Low noise amplifier is the first stage in the wireless transceiver, its high performance can ensure front-end of RF working successfully.So the research of ultra-wideband CMOS LNA is great importance for theory and practice.Firstly,this paper discussed something about ultra-wide band LNA study actuality and characteristic of CMOS RFIC.Secondly, we analyzed several familiar input impedance match circuits,and compared their advantages and disadvantages. After that,butterworth filter was designed as input match circuits.The cascode structure has many advantages,such as good gain, small Miller effect, simple structure etc.So the paper chose it as primary magnifying structure of circuits. Thirdly,we educed the optimal size of input transistor by noise improved theory under power limit. A stage matching scheme was used for heightening gain and reducing noise figure. Capacitance-coupling load circuit was used for fulfilling the demand of wide frequency. To optimize the performance of LNA,the paper designed voltage biased circuit and current-source circuit.The voltage of ultra-wide band LNA is 1.5V,based on TSMC 0.18μm CMOS process.And this LNA is simulated by ADS2008.The simulation results show that,it works in 3-5GHz, the noise figure is under 2.3dB.The gain is better than 12dB,and the maximum gain is above 14dB.The gain fluctuating range is less than 2.4dB.1dB compression point is about-15dBm. The input and output impedance match are better than-10dB. The power consumption is 19mW.更多还原