A 40 dBm AlGaN/GaN HEMT power amplifier MMIC for SatCom applications at K-band

The design, realization, and characterization of a K-band high power amplifier with a saturated output power of 40dBm is described in this paper. The amplifier is realized using a 250nm gate length AlGaN/GaN HEMT MMIC technology on semi-insulating SiC substrates. The two-stage amplifier is designed with two 6×90 µm HEMT cells in the driver and four 8×100 µm HEMT cells in the final stage and thus exhibits a relatively aggressive staging ratio of 1∶3. When measured with a supply voltage of 32V, the amplifier delivers a saturated output power of 40dBm at 18 GHz. The peak PAE at this frequency is 30%, and the linear gain exceeds 20 dB. These results are state-of-the-art performance with regard to power/efficiency at K-band.