Pre-distortion design for non-linear power amplifiers

Power amplifiers are vital part of communication systems for long distance communication. They are used to amplify the power of incoming signals. The power gain characteristics of these amplifiers show a non-linear behavior for larger input power signals. The non-linear power gain response decreases the efficiency of power amplifier. To alleviate the negative effects of non-linear gain responses of the power amplifiers, researchers model the gain responses and calculate or approximate their inverse called pre-distortions, and the incoming signal is passed through the pre-distortion unit before it is fed to the power amplifier such that the gain responses of the power amplifiers show a linear characteristic. In this thesis, we first review the well-known pre-distortion methods available in the literature, and then propose a novel approach for pre-distortion design. The proposed approach uses the concept of analog signal reconstruction from its samples. We use sinc(⋅) function for the modeling of amplifier gain response and pre-distortion design. The proposed method can be seen as the optimum implementation of indirect learning algorithm used for pre-distortion design.