A 62-to-68GHz linear 6Gb/s 64QAM CMOS doherty radiator with 27.5%/20.1% PAE at peak/6dB-back-off output power leveraging high-efficiency multi-feed antenna-based active load modulation

Extreme throughput requirements on future mm-wave systems, e.g., 5G links, necessitates the use of spectrum-efficient modulations that often come with high peak-to-average power ratios (PAPRs). Therefore, there is an increasing need for mm-wave power amplifiers (PAs) with high power back-off (PBO) efficiency, so that wideband large-PAPR signals can be transmitted with high energy efficiency. Among various PA PBO efficiency-enhancement techniques, Doherty PAs feature wideband modulations and low baseband DSP overhead, making them particularly promising candidates for high-speed mm-wave systems.