Microwave Circuit Design: A Practical Approach Using ADS

Chapter 9. Power Amplifiers

Chapter Outline

9.1 Introduction

9.2 Active Devices for Power Amplifiers

9.3 Optimum Load Impedances

9.4 Classification

9.5 Design Example

9.6 Power Amplifier Linearity

9.7 Composite Power Amplifiers

9.8 Summary

9.1 Introduction

A power amplifier is generally located just before the antenna, and determines the transmitting power level of a communication system. The design of a power amplifier is significantly different from that of the low-noise amplifier presented in Chapter 8. To demonstrate the difference, suppose that two amplifiers are designed with the same active device; one is based on the small-signal design presented in Chapter 8 and has the maximum small-signal gain; the other produces the maximum output ...