A 6.5–16.5 GHz Low Noise Amplifier Based on GaAs pHEMT

Based on 0.25- μm GaAs pseudomorphic high electron mobility transistor (pHEMT), a 6.5–16.5 GHz low noise amplifier (LNA) is designed. The LNA employs the single stage cascode structure to achieve high gain. The structure adopts a source degeneration inductor to improve the noise figure (NF) and stability. By analyzing the RLC negative feedback network, the gain flatness in the specific bandwidth is optimized and the stability of circuit is improved. The simulation shows maximum NF less than 2dB, the average gain is 12.5dB and the flatness is ±0.45dB over the range of 6.5–16.5 GHz. Excellent input and output return loss better than 10dB are obtained.