A wide dynamic range analog predistortion-type linearizer using self-cancellation scheme

摘要

A new radio frequency linearized power amplifier (LPA) system for wideband-code-division-multiple-access (WCDMA) application is demonstrated. The main amplifier is a parallel combination of drive amplifiers, and the same type of drive amplifier is also used to generate the predistortion signal. Self-cancellation of the intermodulation-distortion (IMD) components is obtained by the generic identity between the nonlinear characteristics of the main amplifier and the predistortion signal, both of which are originated from the same type of devices. Such self-cancellation scheme exhibits the improvement of 13 dB in the adjacent channel leakage ratio (ACLR) for WCDMA signal excitation.