Linearization of microstrip RF power amplifier loaded with the broadband matching circuits for the efficiency maintenance

In this paper a RF amplifier is designed in microstrip technique for broadband application in the frequency range 0.75-1.15 GHz. Its linearization has been performed by the second- and fourth-order nonlinear signals fed at the transistor gate and drain throughout the broadband matching circuits designed to provide high amplifier efficiency and adequate power level of the injected linearization signals. The effects of the linearization are considered through the simulation for two sinusoidal signals with different frequency interval between them setting on from 10 MHz and going up to 50 MHz at different input power levels up to saturation, as well as for an OFDM digitally modulated signal.