A Simple Method to Estimate the Output Power and Efficiency Load–Pull Contours of Class-B Power Amplifiers

This paper describes a simple method to estimate the output power and efficiency load-pull contours of a class-B power amplifier (PA). Using successively improved-but still simple and intuitive-field-effect transistor nonlinear iDS (vGS,vDS) current models, this work starts by explaining the poor efficiency predictions provided by the Cripps load-line method, to then derive refined expressions to predict the output power load-pull contours and a novel analysis that produces useful estimates of the efficiency load-pull contours. These estimates are believed to constitute an invaluable tool for the analysis and design of single-ended class-B or Doherty PAs.

[1]  H. Zirath,et al.  A new empirical nonlinear model for HEMT and MESFET devices , 1992 .

[2]  Jose C. Pedro,et al.  Efficiency dependence on the load-pull ratio of a Doherty PA , 2014, 2014 IEEE MTT-S International Microwave Symposium (IMS2014).

[3]  P.A. Blakey,et al.  Generalized Kushner analysis of RF power amplifiers , 1999, 1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282).

[4]  Jose C. Pedro,et al.  A Unified Theory for Nonlinear Distortion Characteristics in Different Amplifier Technologies , 2005 .

[5]  Franco Giannini,et al.  Nonlinear mixed analysis/optimization algorithm for microwave power amplifier design , 1995 .

[6]  F. Raab,et al.  Power amplifiers and transmitters for RF and microwave , 2002 .

[7]  S.C. Cripps,et al.  A Theory for the Prediction of GaAs FET Load-Pull Power Contours , 1983, 1983 IEEE MTT-S International Microwave Symposium Digest.

[8]  Franco Giannini,et al.  Design-oriented non-linear analysis of class-AB power amplifiers , 1993, 1993 IEEE MTT-S International Microwave Symposium Digest.

[9]  R.B. Stancliff,et al.  Harmonic Load-Pull , 1979, 1979 IEEE MTT-S International Microwave Symposium Digest.

[10]  James Haydn Nelson,et al.  Enhanced RF Power Leveling with FPGA-Based Instrumentation [Application Notes] , 2013, IEEE Microwave Magazine.

[11]  Christian Fager,et al.  Prediction of IMD in LDMOS transistor amplifiers using a new large-signal model , 2002 .

[12]  J. H. Qureshi,et al.  LDMOS Technology for RF Power Amplifiers , 2012, IEEE Transactions on Microwave Theory and Techniques.

[13]  H. Kondoh.  FET power performance prediction using a linearized device model , 1989, IEEE MTT-S International Microwave Symposium Digest.

[14]  C. Weitzel,et al.  RF power amplifiers for wireless communications , 2002, 24th Annual Technical Digest Gallium Arsenide Integrated Circuit (GaAs IC) Symposiu.

[15]  F. van Rijs,et al.  Efficiency improvement of LDMOS transistors for base stations: towards the theoretical limit , 2006, 2006 International Electron Devices Meeting.

[16]  Y. Takayama.  A New Load-Pull Characterization Method for Microwave Power Transistors , 1976 .

[17]  Franco Giannini,et al.  High Efficiency RF and Microwave Solid State Power Amplifiers , 2009 .

[18]  Robert H. Caverly,et al.  HF, VHF, and UHF systems and technology , 2002 .

[19]  J. Benedikt,et al.  Experimental evaluation of an active envelope load pull architecture for high speed device characterization , 2005, IEEE MTT-S International Microwave Symposium Digest, 2005..

[20]  D. Kuylenstierna,et al.  LDMOS Modeling , 2013, IEEE Microwave Magazine.