Linear and Efficient NFET-MESFET 5G Cascode Power Amplifiers Using 45nm SOI CMOS

摘要

Integrated n-channel NFET-MESFET cascode power amplifiers (PAs) have been fabricated using a 45 nm SOI CMOS technology optimized for 5G applications. The cascode architecture combines the RF performance of the 40nm gate length NFET (f_max > 340 GHz) with the high voltage capability (V_DD > 10 V) of the SOI MESFET. Load-pull measurements at 5.8 GHz confirm that a PA with 18 dBm saturated output power, >21dB gain, and >50% power added efficiency (PAE) can support 64QAM signals with 3% error vector magnitude and 25% average PAE at 6dB backed off power levels. These results suggest that an NFET-MESFET cascode PA might be suitable for low-cost 5G picocell/femtocell applications without the need for digital pre-distortion.