An 18–31-GHz GaN-Based LNA With 0.8-dB Minimum NF and High Robustness

Benefited from the high breakdown voltage and low noise characteristics, GaN high-electron mobility transistors (HEMTs) can be used for manufacturing of robust low noise amplifiers (LNAs). Therefore, limiter circuits which protect the entire system are no longer necessary and systems with smaller volume can be realized. In this letter, a LNA with low noise figure (NF) and longtime survivability for high input power stress is designed and fabricated in a 100-nm GaN process. The LNA achieves a minimum NF of 0.8 dB and a flat gain of 21 ± 0.5 dB from 18 to 31 GHz. The LNA can survive in a 28-30-dBm input stress for 60 min without significant performance degradation.