Robust Broadband (4 GHz - 16 GHz) GaN MMIC LNA

Abstract

We report robust GaN MMIC LNA operating over 4 GHz-6 GHz frequency range. An FET biased in common-drain configuration is used on the second stage of the MMIC to obtain good input return loss at the optimum noise match over the entire frequency range. The measured noise figure of the MMIC is less than 2 dB over the 4.5 GHz to 16 GHz frequency range and NF has a minimum of 1.45 dB at a frequency of 6.5 GHz. The MMIC gain is more than 10 dB and the input return loss of the MMIC is less than -10 dB over the 4 GHz-15 GHz frequency range. Reported MMIC can survive 5.4 W of incident RF power without front end protection. To the authors knowledge this is the best combination of the noise figure, input return loss, RF survivability and broadband response reported to date in this frequency range using GaN technology. The noise figure of the reported GaN MMIC is 0.5 dB lower than the overall noise figure of an equivalent GaAs pHEMT module consisting of the state of the art LNA and a 5 Watt power limiter at the front end.