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

• Published in: 2008 IEEE Compound Semiconductor Integrated Circuits Symposium pp. 1 - 4
• Main Authors: Kobayayashi, K.W., Yao Chung Chen, Smorchkova, I., Heying, B., Luo, W.-B., Sutton, W., Wojtowicz, M., Oki, A.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.10.2008
• Subjects: Aluminum gallium nitride; Broadband amplifiers; Gallium nitride; HEMTs; III-V semiconductor materials; MMICs; Noise figure; Noise measurement; Power generation; Temperature
• ISBN: 1424419395; 9781424419395
• ISSN: 1550-8781; 2374-8443
• DOI: 10.1109/CSICS.2008.54

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.