X-Band GaN Monolithic Microwave Integrated Circuit Low Noise Amplifier Using Inductive Source Degeneration

In this study, an X-band GaN monolithic microwave integrated circuit (MMIC) low-noise amplifier is designed and fabricated for RF transceiver modules using a 0.2 μm ETRI GaN HEMT process. Through the application of a feedback microstrip line at the source of the transistor, the amplifier operation is stabilized, and a compromised impedance trace of the input impedance and noise matching is obtained, which minimizes the degradation of the maximum available gain and minimum noise figure. The developed MMIC low noise amplifier, which uses simple matching and biasing circuits as matching elements, exhibits a linear gain of more than 20 dB and a noise figure of 1.5～2.0 dB from 8.7 to 11.5 GHz. A single-tone power test shows an output P1dB of 17.1～24.3 dBm, and a two-tone IMD measurement shows an output IP3 of 27.4～32.4 dBm in the same frequency range.