An Ultra Wideband GaAs pHEMT Low Noise Amplifier for 3.3-24.5 GHz_1

An Ultra-Wideband (UWB) low noise amplifier (LNA) using the GaAs pseudomorphic high electron mobility transistor (GaAs pHEMT) ED02AH technology with 0.25?m gate length is modeled and designed with the aid of Advance Design System (ADS) software. Capacitive neutralization technique is used in the output stage, and a common gate structure with T-type impedance matching structure is used for the input stage to yield a wideband matched amplifier. The simulation results show that noise (NF) figure varies between 2.8 and 3.4 dB in the frequency range 3.3 to 24.5 GHz, while the power gain, S21 is 17.5±0.5 dB. The input and output return losses (S11, S22) are better than 11.25 dB, while the amplifier is stable over the frequency range of 3.3- 24.5 GHz.