Study And Design Of Millimeter Wave Power Amplifier In 40nm CMOS

Fabricated in CMOS,this thesis presents two kinds of power amplifier which are designed for baes station application of E-Band wireless communication purpose.The two power amplifier are designed using two different ways of power combining,and consist of serval modules which are driver amplifier,power splitter,the first stage amplifier,the second stage amplifier and power combiner network.This thesis focuses on the design and optimization of CMOS transistor in millimeter-wave frequency,analysis and applications of passive device,analysis for the impedance imbalance of passive device,the design of E-Band power amplifier and etc.In the section of transistor design and optimization,oriented by the application of power amplifier,this thesis mainly studies the power gain capability of a CMOS transistor and the impact of a layout and parasitic,and some solutions for optimization are proposed.Besides,typical largesignal performance,such as DC point drifted,changes of inside capacitors,are discussed.For the analysis and applications of passive devices,this thesis mainly introduces the way of impedance matching using passive devices,and also proposes a new understanding of wide-band impedance matching,which can be concluded as how to achieve a flat impedance characteristic and how to make an impedance transform.Besides,this thesis also introduces some equivalent circuits of transformers,power amplifier and power splitter,a power combining solution for E-Band power amplifier is finally proposed.For the imbalance analysis,after introducing what imbalance is,this thesis proposes a theory from the aspect of circuits analysis.In this theory,in order to get the impedance of one port,it should be excited by a voltage source,then the impedance of this port can be equivalent to the current status in the passive device,and since the port impedance is visualized,one can easily find the source of imbalance,and optimize the passive device.According to the simulation results,some optimizations are proposed,and the imbalance of passive devices reduce by 30% after optimization.At the end,this thesis presents the design of E-Band power amplifier from the aspects of basic knowledge which are demands for power amplifier at high order modulation,gain compression,gain expanding,AM-AM distortion and AM-PM distortion.After analyzing the demands of application,the numerical targets of the power amplifier are confirmed,and the circuit framework is chosen.Besides,this thesis also studies the impedance matching and the stability of the power amplifier.Finally,the layout picture and simulation results are presented,according to the simulation,each of the two power amplifier has a maximum gain over 20 dB,OP1 dB over 12 dBm,and maximum Psat 15 dBm.