Radio-Frequency Electronics- Circuits and Applications-2009

Contents Preface page xiii 1 Introduction 1 1.1 RF circuits 2 1.2 Narrowband nature of RF signals 3 1.3 AC circuit analysis – a brief review 3 1.4 Impedance and admittance 4 1.5 Series resonance 4 1.6 Parallel resonance 5 1.7 Nonlinear circuits 5 Problems 5 2 Impedance matching 10 2.1 Transformer matching 11 2.2 L-networks 12 2.3 Higher Q – pi and T-networks 14 2.4 Lower Q – the double L-network 15 2.5 Equivalent series and parallel circuits 16 2.6 Lossy components and efficiency of matching networks 16 Problems 17 3 Linear power amplifiers 19 3.1 Single-loop amplifier 19 3.2 Drive circuitry: common-collector, common-emitter, and common-base 20 3.3 Shunt amplifier topology 22 3.4 Dual-polarity amplifiers 22 3.5 Push–pull amplifiers 23 3.6 Efficiency calculations 25 3.7 AC amplifiers 26 3.8 RF amplifiers 29 3.9 Matching a power amplifier to its load 31 Problems 31 4 Basic filters 34 4.1 Prototype lowpass filter designs 35 4.2 A lowpass filter example 36 4.3 Lowpass-to-bandpass conversion 38 Appendix 4.1 Component values for normalized lowpass filters 41 Problems 43 References 45 5 Frequency converters 46 5.1 Voltage multiplier as a mixer 46 5.2 Switching mixers 48 5.3 A simple nonlinear device as a mixer 51 Problems 53 6 Amplitude and frequency modulation 54 6.1 Amplitude modulation 55 6.2 Frequency and phase modulation 58 6.3 AM transmitters 62 6.4 FM transmitters 65 6.5 Current broadcasting practice 65 Problems 66 7 Radio receivers 67 7.1 Amplification 67 7.2 Crystal sets 68 7.3 TRF receivers 68 7.4 The superheterodyne receiver 69 7.5 Noise blankers 74 7.6 Digital signal processing in receivers 75 Problems 75 References 76 8 Suppressed-carrier AM and quadrature AM (QAM) 77 8.1 Double-sideband suppressed-carrier AM 77 8.2 Single-sideband AM 78 8.3 Product detector 80 8.4 Generation of SSB 81 8.5 Single-sideband with class C, D, or E amplifiers 83 8.6 Quadrature AM (QAM) 84 Problems 85 References 86 9 Class-C, D, and E Power RF amplifiers 87 9.1 The class-C amplifier