C波段高增益低噪声放大器单片电路设计

Design of C-Band High Gain Low Noise Amplifier

主要介绍了C波段高增益低噪声单片放大器的设计方法和电路研制结果。电路设计基于Agilent ADS微波设计环境,采用GaAs PHEMT工艺技术实现。为了消除C波段低噪声放大器设计中在低频端产生的振荡,提出了在第三级PHEMT管的栅极和地之间放置RLC并联再串联电阻吸收网络的方法,降低了带外低频端的高增益,从而消除了多级级联低噪声放大器电路中由于低频端增益过高产生的振荡。通过电路设计与版图电磁验证相结合的方法,使本产品一次设计成功。本单片采用三级放大,工作频率为5～6GHz,噪声系数小于1.15dB,增益大于40dB,输入输出驻波比小于1.4∶1,增益平坦度ΔGp≤±0.2dB,1dB压缩点P-1≥10dBm,直流电流小于90mA。

The design method and test results of a C-band high gain low noise amplifer were described.The circuit was fabricated by GaAs pseudo-morphic high electron mobility transistor（PHEMT） process and designed with Agilent ADS.An effective method for eliminating low frequency oscillation in C-band monolithic microwave integrated circuit（MMIC） low noise amplifier was proposed,that is,a parallel RLC resonant absorbing network was placed between gate electrode of PHEMT of the third stage and ground.The high gain of lower frequencies out side of working frequency band is reduced and low frequency oscillation is eliminated.The MMIC design combines the circuit design and layout EM simulation for better design accuracy.The three-stage amplifier adopts a 5 V DC supply,and its frequency range is 5-6 GHz,noise figure is less than 1.15 dB,gain is more than 40 dB,input and output VSWRs are less than 1.4∶1,gain flatness is less than ±0.2 dB,output power is more than 10 dBm at 1 dB compression,DC current is less than 90 mA.