一种新型噪声消除宽带低噪声放大器

Broadband Low Noise Amplifier Using Improved Noise Cancellation Technology

噪声消除技术是设计低噪声放大器(LNA)时常用的技术之一,而如何解决LNA噪声与功耗的矛盾始终是设计的难点。文章提出一种新型噪声消除结构,通过主辅支路之间添加反馈回路的方式,在不增加功耗的情况下,实现了消除主辅支路噪声的目的。基于180 nm CMOS工艺,设计了一款应用该噪声消除结构的宽带低噪声放大器。仿真结果显示,该LNA的带宽为0.40~2.36 GHz,S_(11)与S_(22)均小于-10 dB,S12小于-30 dB,最大S_(21)为14.5 dB,噪声系数为2.20~2.34 dB,功耗仅为9 mW。

Noise cancellation is a common technology in the design of low noise amplifiers(LNA).Solving the contradiction between noise and power consumption is the most difficult challenge during the design process.A new noise cancellation structure is proposed in this study.Noise in the main and auxiliary branches is eliminated by adding a feedback loop between the main and auxiliary branches,without increasing power consumption.Based on a 180 nm CMOS technology,a wideband low noise amplifier with the noise cancellation structure is designed.Simulation results show that the bandwidth of the LNA is 0.4-2.36 GHz,both S_(11)and S_(22)are less than-10 dB,S12 is less than-30 dB,the maximum S_(21)is 14.5 dB,the noise factor is 2.20-2.34 dB,and the power consumption is 9 mW.