Design Guidelines for Improving the Power‐Added-Efficiency of CMOS RF Multipath‐Polyphase Power Amplifiers

Abstract

This chapter deals with the key factors for power management in multipath polyphase Power Amplifiers. Design guidelines for keeping the adequate balance between power gain and the conduction angle at which the amplifier is driven are provided. A multipath polyphase Power Amplifier based on the use of a predriver upconverter is presented. The novelty of the advised architecture lies in its ability to modify the conduction angle of the signal that drives the Power Amplifier and regulates the power provided to the Power Amplifier. A detailed study of the functionality and performance of the proposed amplifier is described. A new RF multipath polyphase Power Amplifier whose Power-Added-Efficiency is, theoretically, high at peak and average output power even in the presence of a large power back off is introduced. Additionally, the suppression of distortion components in function of the number of paths used still is preserved in the new architecture.