RF Front-End World Class Designs
Janine Sullivan Love
with
Cheryl Ajluni John Blyler Christopher Bowick Joe Carr Farid Dowla Michael Finneran Andrei Grebennikov Ian Hickman Leo G. Maloratsky Ian Poole Nathan O. Sokal Steve Winder HankZumbahlen
AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Newnes is an imprint of Elsevier Newnes Contents
Preface xi
About the Editor xiii
About the Contributors xv
Chapter 1: Radio Waves and Propagation 1 1.1 Electric Fields 1 1.2 Magnetic Fields 3 1.3 Radio Waves 3 1.4 Frequency to Wavelength Conversion 5 1.5 Radio Spectrum 6 1.6 Polarization 7 1.7 How Radio Signals Travel 9 1.8 Refraction, Reflection and Diffraction 10 1.9 Reflected Signals 12 1.10 Layers above the Earth 13 1.11 Ground Wave 17 1.12 Skywaves 18 1.13 Distances and the Angle of Radiation 21 1.14 Multiple Reflections 22 1.15 Critical Frequency 23 1.16 MUF 23 1.17 LUF 24 1.18 Skip Zone 24 1.19 State of the Ionosphere 24 1.20 Fading 25 1.21 Ionospheric Disturbances 26 1.22 Very Low Frequency Propagation 27 1.23 VHF and Above 28 1.24 Greater Distances 28 vi Contents
1.25 Troposcatter 29 1.26 Sporadic E 30 1.27 Meteor Scatter 31 1.28 Frequencies above 3 GHz 32
Chapter 2: RF Front-End Design 33 2.1 Higher Levels of Integration 34 2.2 Basic Receiver Architectures 36 2.3 ADC'S Effect on Front-end Design 57 2.4 Software Defined Radios 58 2.5 Case Study—Modern Communication Receiver 59
Chapter 3: Radio Transmission Fundamentals for WLANs 65 3.1 Defining Transmission Capacity and Throughput 65 3.2 Bandwidth, Radios, and Shannon's Law 67 3.3 Bandwidth Efficiency 69 3.4 Forward Error Correction (FEC) 71 3.5 Radio Regulation 72 3.6 Licensed Versus Unlicensed Radio Spectrum 73 3.7 Unlicensed Spectrum in the Rest of the World 75 3.8 General Difficulties in Wireless 76 3.9 Basic Characteristics of 802.11 Wireless LANs 81 3.10 Conclusion 82
Chapter 4: Advanced Architectures 83 References 94
Chapter 5: RF Power Amplifiers 95 5.1 Power Amplifier Class of Operation 96 5.2 Conclusion 113 References 114
Chapter 6: RF Amplifiers 115 6.1 Noise and Preselectors/Preamplifiers 116 6.2 Amplifier Configurations 117 6.3 Transistor Gain 117 6.4 Classification by Common Element 118 6.5 Transistor Biasing 120 Contents vii
6.6 Frequency Characteristics 122 6.7 JFET and MOSFET Connections 123 6.8 JFET Preselector 123 6.9 VHF Receiver Preselector 127 6.10 MOSFET Preselector 127 6.11 Voltage-tuned Receiver Preselector 129 6.12 Broadband RF Preamplifier for VLF, LF and AM BCB 129 6.13 Push-pull RF Amplifiers 132 6.14 Broadband RF Amplifier (50 Ohm Input and Output) 138
Chapter 7: Basics of PA Design 141 7.1 Spectral-domain Analysis 141 7.2 Basic Classes of Operation: A, AB, В, and С 147 7.3 Active Device Models 156 7.4 High-Frequency Conduction Angle 162 7.5 Nonlinear Effect of Collector Capacitance 169 7.6 Push-Pull Power Amplifiers 172 7.7 Power Gain and Stability 178 7.8 Parametric Oscillations 189 References 193
Chapter 8: Power Amplifiers 797 8.1 Safety Hazards to Be Considered 197 8.2 First Design Decisions 198 8.3 Levelers, VSWRP, RF Routing Switches 199 8.4 Starting the Design 199 8.5 Low-pass Filter Design 200 8.6 Discrete PA Stages 203 References 226
Chapter 9: RF/IF Circuits 227 9.1 Mixers 229 9.2 Modulators 235 9.3 Analog Multipliers 236 9.4 Logarithmic Amplifiers 243 9.5 Tru-Power Detectors 248 9.6 VGAs 251 9.7 Direct Digital Synthesis 259 viii Contents
9.8 PLLs 268 Bibliography 289
Chapter 10: Filters 293 10.1 Classification 293 10.2 Filter Synthesis 296 10.3 LPFs 297 10.4 BPFs 305 References 321
Chapter 11: Transmission Lines and PCBs as Filters 325 11.1 Transmission Lines as Filters 326 11.2 Open-circuit Line 327 11.3 Short-circuit Line 328 11.4 Use of Misterminated Lines 329 11.5 Printed Circuits as Filters 336 11.6 Bandpass Filters 338 References 339
Chapter 12: Tuning and Matching 341 12.1 Vectors for RF Circuits 341 12.2 L-C Resonant Tank Circuits 344 12.3 Tuned RF/IF Transformers 348 12.4 Construction of RF/IF Transformers 349 12.5 Bandwidth of RFЯF Transformers 351 12.6 Choosing Component Values for L-C Resonant Tank Circuits 355 12.7 The Tracking Problem 357 12.8 The RF Amplifier/Antenna Tuner Problem 358 12.9 The Local Oscillator (LO) Problem 361 12.10 Trimmer Capacitor Method 361 12.11 Impedance Matching in RF Circuits 363 12.12 Transformer Matching 363 12.13 Resonant Transformers 364 12.14 Resonant Networks 366 12.15 Inverse-L Network 367 12.16 ir-network 367 12.17 Split-capacitor Network 368 12.18 Transistor-to-Transistor Impedance Matching 369 Contents ix
Chapter 13: Impedance Matching 373 13.1 Background 373 13.2 The L Network 376 13.3 Dealing with Complex Loads 380 13.4 Three-element Matching 383 13.5 Low-ß or Wideband Matching Networks 389 13.6 The Smith Chart 395 13.7 Impedance Matching on the Smith Chart 414 13.8 Software Design Tools 422 13.9 Summary 439
Chapter 14: RF Power Amplifier Linearization Techniques 447 14.1 RF Amplifier Nonlinearity 442 14.2 Linearization Techniques 445 14.3 Digital Baseband Predistortion 450 14.4 Conclusion 458 References 458
Index 461
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