采用新型电流舵结构的增益可调UWB LNA

摘要

A variable gain UWB LNA operating in 3 GHz～5 GHz frequency range is presented based on TSMC 0.18 μm standard CMOS process.A common-gate structure with a local feedback stage is adopted in the input stage of the LNA to achieve ultrawideband input match and optimize the noise performance.A novel current steering structure is proposed to realize the continuous variable gain of amplifiers.The output stage employs a source-follower to achieve excellent output match.The LNA is simulated and verified with ADS2009,the results show that the LNA operating in 3 GHz～5 GHz frequency range can realize a continuous gain tuning range of 25 dB,a maximum gain of 24 dB,an input reflection of less than-11 dB,an output reflection of less than-14 dB,a minimum noise figure of 2.3 dB,and an ⅡP3 of 4 dBm.The LNA consumes only 8.8 mW with a 1.2 V power supply.%基于TSMC 0.18 μm CMOS工艺,设计了一款工作在3 GHz～5 GHz频段的增益可调超宽带低噪声放大器(LNA).LNA输入级采用局部反馈的共栅结构,实现了超宽带输入匹配和良好的噪声性能;放大电路级采用提出的新型电流舵结构,实现了放大器增益连续可调;输出级采用源极跟随器,获得了良好的输出匹配.利用ADS2009进行仿真验证,结果表明,在3 GHz～5 GHz工作频段内,LNA获得了25 dB的增益可调范围,最高增益达到24 dB,输入端口反射系数小于-11 dB,输出端口反射系数小于-14 dB,最小噪声系数为2.3 dB,三阶交调点(ⅡP3)为4 dBm,在1.2V电压下,电路功耗仅为8.8 mW.