Robust X-band GaN LNA with Integrated Active Limiter

In this paper, design and measurement of X-Band monolithic microwave integrated circuit (MMIC) low noise amplifiers (LNA) using a commercial 0.25 um microstrip GaN-on-SiC high electron mobility transistor (HEMT) technology are reported. Using a novel active limiting approach in measurements, lower than 1.75 dB noise figure (NF) and higher than 16 W CW input power survivability is obtained from a single chip. To the best of authors' knowledge, said LNA has the highest input power handling performance for the given noise figure level although transistors are not optimized for low-noise operation and input matching network is realized to compromise between noise figure and input return loss which is better than 10 dB. Results are promising for single chip GaN frontend transceiver architecture realization.