Rf Power Amplifier Efficiency Improvement In Technology Research

As the most crucial component for efficiency of transmitter, power-amplifier (PA) has been researched by scholars or engineers from home and abroad. According to different modulated signal-for Constant Envelope Signal (CES) or Varying Envelope Signal (VES), information is carried by phase or amplitude, or both.As the best candidate for CES, high efficiency PA is one focus of my study including the design and implementation methods of class-F and harmonically tuned Inverse Class-F PA. The study of class-F has theoretically synthesized practical device effects, and put forward one compact micro-strip topology to realize it. Using practical tools and harmonic control method, and considering the actual complexity of the GaN HEMT model and nonlinear drain capacitance model, the harmonically tuned Inverse class F PA achieves delivered power of39.9dBm, drain efficiency of81%at3.5GHz.Regard to VES, Doherty PA meets the acceptable back-off linearity and high drain efficiency. Another focus of this study is to put forward one DPA of broadband high back-off efficiency considering the limitations for widebandth. The DPA is fabricated with Si-LDMOS and verified within2.25～2.55GHz bandwidth. Experimental results show delivered power fluctuations of42.6±0.6, and drain efficiency higher than41%at7dB back-off. Design and implementation of several power amplifiers provides a method for high efficiency power amplifier used in contemporary transmitter.This article is divided into six chapters. Chapter Ⅰ is an introduction describing the purpose of this thesis and the choice of high-efficiency PA. Chapter Ⅱ begins with the PA of the major technical specifications and describes involved concepts and test-simulation platform. Chapter Ⅲ and Ⅳ are the realization of a compact class F power amplifier, and a detailed theoretical analysis of high-efficiency PA method for harmonically tuned inverse class F, verifications are also carried out. Chapter Ⅴ of the broadband Doherty PA using improved methods and verified by experiment. Chapter Ⅵ of this thesis summarizes an overview and preview of future PA.