RF Power Amplifiers for Wireless Communications, Second Edition (Artech House Microwave Library (Hardcover))

Reviewing the previous edition, IEEE Microwave Magazine boasted, "anyone designing power amplifiers will find this book thought provoking and useful." Professionals in the field agreed as the book went on to be one of our top-selling RF design titles. This extensively revised edition of RF Power Amplifiers for Wireless Communications offers practitioners a comprehensive, practical, and up-to-date understanding of how to tackle a PA (power amplifier) design with confidence and quickly determine the cause of malfunctioning hardware. Among the numerous updates, the Second Edition includes five new chapters on some of today's most important topics, such as class AB PAs at GHz frequencies; switching PA modes at GHz frequencies; signals, modulation systems, and PA nonlinearities; power amplifier bias circuit design; and and load-pull techniques. Supported with nearly 200 illustrations, the book contains the most complete survey of RF PA efficiency enhancement and linearization techniques in a single volume. "...a troubleshooting guide to power amplifier (PA) design ...explains how to design suitable matching networks, use envelope simulation techniques, maintain high efficiency operation, & understand Class D, E, and F modes. Front-cover Front-matter RF Power Amplifiers for Wireless Communications DISCLAIMER OF WARRANTY Copyright Page Contents v Preface to the Second Edition xi Chapter 1 Introduction 1 1.1 Introduction 1 1.2 Linear RF Amplifier Theory 2 1.3 Weakly Nonlinear Effects: Power and Volterra Series 5 1.4 Strongly Nonlinear Effects 1.5 Nonlinear Device Models for CAD 9 1.6 Conjugate Match 11 1.7 RF Power Device Technology 14 References 15 Chapter 2 Linear Power Amplifier Design 17 2.1 Class A Amplifiers and Linear Amplifiers 17 2.2 Gain Match and Power Match 19 2.3 Introduction to Load-Pull Measurements 20 2.4 Loadline Theory 21 2.5 Package Effects and Refinements to Load-Pull Theory 27 2.6 Drawing the Load-Pull Contours on CAD Programs 31 2.7 Class A Design Example 31 2.8 Conclusions 36 References 37 Chapter 3 Conventional High Efficiency Amplifier Modes 3.1 Introduction 39 3.2 Reduced Conduction Angle—Waveform Analysis 40 3.3 Output Termination 43 3.4 Reduced Conduction Angle Mode Analysis—FET Model 47 3.5 Reduced Conduction Angle Mode Analysis—BJT Model 55 3.6 Effect of I-V “Knee” 59 3.7 Input Drive Requirements 61 3.8 Conclusions 65 References 65 Chapter 4 Class AB PAs at GHz Frequencies 67 4.1 Introduction 67 4.2 Class AB Using a Capacitive Harmonic Termination—The Class J PA 68 4.3 Nonlinear Device Characteristics 77 4.4 Nonlinear Capacitance Effects in RF Power Devices 81 4.5 Conclusions 89 References 89 Chapter 5 Practical Design of Linear RF Power Amplifiers 91 5.1 Low-Pass Matching Networks 92 5.2 Transmission Line Matching 100 5.3 Shorting the Harmonics 102 5.4 A Generic MESFET 105 5.5 A 2W Class B Design for 850 MHz 107 5.6 The Pi Section Power Matching Network 112 5.7 Pi Section Analysis for PA Design 115 5.8 Class J Design Example 122 5.9 HBT Design Example 124 5.10 Conclusions 129 References 131 Chapter 6 Overdriven PAs and the Class F Mode 133 6.1 Introduction 133 6.2 Overdriven Class A Amplifier 134 6.3 Overdriven Class AB Amplifier 139 6.4 Class F: Introduction and Theory 143 6.5 Class F in Practice 149 6.6 The Clipping Model for the Class F Mode—Class FD 155 6.7 PA_Waves 163 6.8 Class F Simulations 164 6.9 Conclusions 171 References 172 Chapter 7 Switching Mode Amplifiers for RF Applications 173 7.1 Introduction 173 7.2 A Simple Switching Amplifier 174 7.3 A Tuned Switching Amplifier 178 7.4 The Class D Switching Amplifier 180 7.4 Class E—Introduction 182 7.5 Class E—Simplified Analysis 183 7.6 Class E—Design Example 192 7.7 Conclusions 198 References 199 Chapter 8 Switching PA Modes at GHz Frequencies 201 8.1 Introduction 201 8.2 Ignoring the Obvious: Breaking the 100% Barrier 202 8.3 Waveform Engineering 205 8.4 PA_Waves 216 8.5 Implementation and Simulation 225 8.6 Conclusions 227 References 229 Chapter 9 Nonlinear Effects in RF Power Amplifiers 231 9.1 Introduction 231 9.2 Two-Carrier Power Series Analysis 233 9.3 Two-Carrier Envelope Analysis 240 9.4 Envelope Analysis with Variable PAR 246 9.5 AM to PM Effects 250 9.6 PA Memory Effects 256 9.7 Digital Modulation Systems 261 9.8 30 Watt LDMOS Test Amplifier Measurements 278 9.9 Conclusions 282 References 283 Chapter 10 Efficiency Enhancement Techniques 285 Introduction 285 10.1 Efficiency Enhancement 286 10.2 The Doherty Amplifier 290 10.3 Realization of the Doherty Amplifier 298 10.4 Outphasing Techniques 303 10.5 Envelope Elimination and Restoration (EER) 309 10.6 Envelope Tracking 311 10.7 Power Converters for EER and ET 314 10.8 Pulse Width Modulation (PWM) 318 10.9 Other Efficiency Enhancement Techniques 323 10.10 Case Studies in Efficiency Enhancement 330 10.11 Conclusions 333 References 334 Chapter 11 Power Amplifier Bias Circuit Design 337 11.1 Introduction 337 11.2 Stability of RF Power Transistors 338 11.3 Bias Supply Modulation Effects 343 11.4 Bias Network Design 350 11.5 Bias Insertion Networks 353 11.6 Prime Power Supply Issues 354 11.7 Bias Control Circuits 355 11.8 Conclusions 356 References 357 Chapter 12 Load-Pull Techniques 359 12.1 Tuner Design for Fundamental Load-Pull 359 12.2 Harmonic Load-Pull 362 12.3 Active Harmonic Load-Pull 365 12.4 Variations, Results, Conclusions 367 References 369 Chapter 13 Power Amplifier Architecture 371 Introduction 371 13.1 Push-Pull Amplifiers 372 13.2 Balanced Amplifiers 380 13.3 Power Combining 387 13.4 Multistage PA Design 391 13.5 Conclusions 394 References 395 Chapter 1 4 Power Amplifier Linearization Techniques 397 Introduction 397 14.1 Introduction to PA Linearization 399 14.2 Predistortion 401 14.3 Feedforward Techniques 410 14.4 Feedback Techniques 419 14.5 Other Linearization Methods 424 14.6 Conclusions 425 References 426 Appendix A PA_Waves 429 Appendix B Spectral Analysis Using Excel IQ Spreadsheets 433 Bibliography 435 Glossary 437 About the Author 441 Index 443 Offers practitioners a comprehensive, practical understanding of how to tackle a PA (power amplifier) design with confidence and quickly determine the cause of malfunctioning hardware. Supported with nearly 200 illustrations, this book contains the survey of RF PA efficiency enhancement and linearization techniques. This book is about radio frequency (RF) power amplifiers (Pas), and a logical starting point would be to recall some of the classical results of linear RF amplifier theory, because many PA designs are simple extensions or modifications of linear designs. Included CD-ROM contains practical tools such as Excel spreadsheets that enable PA performance to be analyzed with specific modulation systems.