A K-band Process-Corner Robust Balanced Power Amplifier Utilizing Current-Mode Adaptive Biasing Network in 65-nm CMOS

This paper presents an adaptive biased K-band balanced power amplifier robust to process corner variations and featuring high modulation data rate with enhanced PAE at power back-off level. The proposed architecture, utilizing current-mode adaptive biasing network (ABN) with adjustable weight and a true power detector, offers a significant improvement in AM-AM distortion over process corner variation, from 5.6dB to 1.7dB, compared with conventional voltage-mode ABN. Fabricated in 65-nm CMOS technology, the measured OP1dB variation of the PA over multi-chips is only 0.5dB. With improved ABN bandwidth, the PA achieves a 4.8Gbps data rates when 256-QAM modulation is applied.