Design Of Silicon-based Millimeter Wave Power Amplifier

Because of internet of things,5G communication,self-driving and other new scenes,the demand for RF and millimeter wave front-end has increased dramatically.Due to its advantages of high integration and low cost,silicon-based process takes a great advantage in realizing the full integration of RF and millimeter wave front-end with digital system.But realizing the full integration of high power modules such as power amplifier is also challenging for its low breakdown voltage and high substrate loss.The rise of the MIMO technology has made the system's power demand for a single power amplifier is reduced,and the possibility of complete integration of the whole system is greatly increased.This paper mainly studies how to design a power amplifier with better performance under the limitation of the silicon-based process.Firstly,this paper introduces three major loss mechanisms of silicon-based passive devices,and analyzes layout physical structure,the equivalent circuit model based on lumped components,the characterization parameters and corresponding extraction methods of passive devices and active devices in silicon-based process,these lay a foundation for the design of millimeter wave power amplifier.Under the limitation of silicon-based process,the power combining technology provides a moderate solution for high output power,this paper studies and compares the on-chip power combining technology.The power combining based on transmission line costs large area and is easy to design,and the principle is relatively simple.Current combining and voltage combining based on transformer provide more design freedom and are widely used.The current combining based on transformer shows better amplitudephase balance compared with voltage power combining.Based on 65 nm CMOS technology and Cascode structure,a driver power amplifier for 24 G FMCW radar is designed.The operating bandwidth of the driver power amplifier is from 21.5GHz to 26.4GHz,The OP1 dB is more than 8.5 dBm,Psat is more than 13 dBm,and the Peak PAE is more than 16.5%.Based on 0.13?m SiGe BiCMOS technology and common-emitter structure with positive feedback neutralization capacitance,a power amplifier for 5G millimeter-wave communication is designed.The first advantage of this power amplifier is the currentreuse technology is used to double the supply voltage,thereby halving the demand for supply current.The other is the whole linearity of the power amplifier is improved by utilizing distortion elimination of AM-AM and AM-PM in front and back stage.By simulating,this power amplifier can provide 16.7dBm output power at 1-dB compression point,with a PAE of 28% and AM-PM less than 2.4°at 28 GHz,and PAE remains 12% at 6dB power back-off from OP1 dB.