Linearization of asymmetrical two-way Doherty amplifier

The linearization effects on asymmetrical two-way Doherty amplifiers for CDMA narrowband and WCDMA wideband digitally modulated signals are presented in this paper. Asymmetrical Doherty amplifier with the additional circuit for linearization has been designed and realized. The linearization approach uses the fundamental signals´ second harmonics and fourth-order nonlinear signals that are extracted at the output of the peaking cell, adjusted in amplitude and phase and injected at the input and output of the carrier cell in Doherty amplifier. Effects of the applied linearization technique have been considered through the simulation process.