砷化镓射频前端LNA设计

Design of GaAs RF front-end LNA

基于砷化镓0.25μm工艺的pHEMT器件,设计了一种具有高线性度、高增益、极低噪声性能的宽带低噪声放大器(LNA).电路为共源共栅结构,并采用级间匹配以达到提高高频增益延展带宽的效果.本设计分为0.7~1.0GHz.1.6~2.2GHz与2.3~2.7 GHz三个频段进行外部匹配,电源电压为5 V,测试结果显示,该低噪声放大器静态工作电流为75 mA,在三个频段分别获得27.2~25.8 dB.22~20 dB、19.2~18.7 dB的高增益,并且每个频段内都有较好的增益平坦度,具有0.45~0.75 dB极低的噪声系数和20~19.5 dBm的输出1 dB压缩点.

A wideband low noise amplifier with high-linearity,high-gain and ultra-low noise is designed and fabricated in a 0.25μm GaAs pHEMT process.A matching network is used between common-gate and common-source transistors in this circuit to obtain larger power gain in higher bands.The measurement results show that the quiescent current of the LNA was 75 mA in 5 V power supply.After external matching in three bands of 0.7~1.0 GHz,1.6~2.2 GHz and 2.3~2.7 GHz,the LNA respectively provide a high and flat gain of 27.2~25.8 dB,22~20 dB and 19.2~18.7 dB,a low noise figure of 0.45~0.75 dB and an OP1dB of 20~19.5 dBm.