A Cool, Sub-0.2 dB, Ultra-Low Noise Gallium Nitride Multi-Octave MMIC LNA-PA with 2-Watt Output Power

This paper reports on a S-,C-band LNA-PA which achieves a sub-0.2 dB noise figure over a multi-octave band and a Psat of 2 Watts at a cooled temperature of -30degC. The GaN MMIC is based on a 0.2 mum AlGaN/GaN-SiC HEMT technology with an fT _~ 75 GHz. At a cool temperature of -30degC and a power bias of 15 V-400 mA, the MMIC obtains 0.25-0.45 dB NF over a 2- 8 GHz band and a linear PldB of 32.8 dBm (_~2 Watts) with 25% PAE. At a medium bias of 12 V-200 mA, the amplifier obtains 0.1- 0.2 dB NF across the same band and a PldB of 32.2 dBm (1.66 Watts) with 35% PAE. The corresponding PSAT is better than 2 Watts. At a low-noise bias of 5 V-200 mA, 0.05-0.15 dB NF is achieved with a PldB > 24 dBm and PAE~33%. These results are believed to be the lowest NF ever reported for a multi-octave fully matched MMIC amplifier capable of > 2 Watts of output power. The ultra-low noise, wide band, and high power obtained at modestly low temperature operation makes this an attractive and practical low-cost solution for applications such as WiMAX, CATV, base-stations, and broadband communication systems.