Modeling of cascode modulated power amplifiers

Abstract

Two models of the cascode modulated polar power amplifier (PA) are presented. The cascode modulated PA, that operates as a switch mode amplifier with class-E like output network, has a highly nonlinear transfer characteristic. The proposed empirical model is based on modeling of the peak drain current through the cascode connected transistors. A simplified analytical model, that uses mathematical expressions to describe the nonlinear transfer characteristic of the cascode modulated PA, is proposed. The behavior of the proposed baseband models is compared with the RF domain simulations in a 0.13µm CMOS process.