7 GHz MMIC GaN Doherty Power Amplifier With 47% Efficiency at 7 dB Output Back-Off

Design and characterization of a 7 GHz MMIC GaN Doherty Power Amplifier on TriQuint technology are presented. To the best of the authors' knowledge, the present circuit, suitable for C-band point-to-point backhaul applications, represents the first example of a working MMIC GaN Doherty. Large signal measurements, averaged over 16 MMICs, exhibited power gain of 10 dB, saturated output power in excess of 37 dBm (3 dB gain compression), together with drain efficiency of 47%, at 7 dB of output back-off, and higher than 35% in a 350 MHz band. Two-tone characterization has shown a carrier to 3rd order intermodulation ratio higher than 25 dB in the Doherty region.