High-power high-efficiency broadband GaN HEMT Doherty amplifiers for base station applications

In this paper, the high-power high-efficiency broadband Doherty power amplifiers based on high-voltage GaN HEMT devices with internal input matching for base station applications are proposed and described. For a three-way Doherty implementation, an exceptionally high output power of 59.5 dBm corresponding to 2-dB gain compression point with a peak efficiency of 78%, efficiency of greater than 50% at 8-dB power backoff and a linear flat power gain of about 12 dB were achieved across 1.8-2.2 GHz. By using a novel high-power broadband inverted Doherty amplifier architecture, a saturated output power of greater than 54 dBm, a power gain of greater than 9 dB and a drain efficiency of about 50% at 7-dB power backoff in a frequency bandwidth of 1.8-2.7 GHz were achieved.