Current techniques for enhancing the efficiency of ultra linear power amplifiers

This paper established a performance baseline for the relatively inefficient class A power amplifier most commonly used today in linear applications and then discusses possible performance enhancements derived from more sophisticated techniques, such as: class B amplifiers, Dougherty PA´s, feed forward amplifiers, digital baseband pre-distortion, LINC (linear amplification using nonlinear components), envelope elimination and restoration (EER), and practical combinations of all these techniques. The design providing requisite broadband performance is emphasized.