A novel linearization technique based on modified baseband signal that modulates carrier second harmonic

Abstract

A novel linearization technique for RF power amplifiers is presented in this paper. The proposed technique uses the modified baseband signal that modulates the fundamental carrier second harmonic. This additional signal processed for linearization is then injected, together with the fundamental useful signal, at the input of the amplifier transistor. Also, a prepared signal for linearization is inserted at the amplifier transistor output. In-phase and quadrature-phase components of the modified baseband signal are formed as the products of the second order nonlinearity of a nonlinear system fed by the useful baseband signal. The effects of the proposed linearization method are considered on a single stage power amplifier for quadrature amplitude modulated signals at different input power levels going up to 1dB below saturation region, as well as for WCDMA digitally modulated signal.