A 174 W high-efficiency GaN HEMT power amplifier for W-CDMA base station applications

AlGaN/GaN high electron mobility transistors (HEMTs) have been developed for current-collapse-free operation at high drain bias voltages. The newly designed single-chip GaN HEMT amplifier for W-CDMA base station applications achieves a record CW output power of 150 W with a high power-added efficiency (PAE) of 54% at 2.1 GHz. The amplifier, combined with a digital pre-distortion (DPD) system, also demonstrates a state of the art efficiency of 40% with an adjacent channel leakage power ratio (ACLR) of less than -50 dBc for 4-carrier W-CDMA signals and reaches the saturated peak power level of 174 W with a drain supply voltage of 63 V. We prove for the first time that the AlGaN/GaN HEMT amplifier can completely fulfills the W-CDMA system requirement.