Optimization analysis of feedforward power amplifier

The efficiency optimization of a feedforward low distortion power amplifier is presented. Based on the principle of distortion compensation, the main amplifier output power, that of subamplifier, and amplifier efficiency have been accurately derived. In the present analysis, the coupling coefficient of main signal and distortion paths is selected as the optimization parameter because it may essentially affect the amplifier performance. Simulation results have been obtained for different values of signal cancel ratio and adjacent channel leakage power. The analysis contributes to the design improvement of a power amplifier of mobile communication base stations.