Behavioral Modeling Accuracy for RF Power Amplifier with Memory Effects

In this paper, a system level behavioural model for RF power amplifier, which exhibits memory effects, and based on multibranch system is proposed. When higher order terms are included, the memory polynomial model (MPM) exhibits numerical instabilities. A set of memory orthogonal polynomial model (OMPM) is introduced to alleviate the numerical instability problem associated to MPM model. A data scaling and centring algorithm was applied to improve the power amplifier modeling accuracy. Simulation results prove that the numerical instability can be greatly reduced, as well as the model precision improved with nonlinear model.

Authors:

• Chokri Jebali
• Noureddine Boulejfen
• Ali Gharsallah
• Fadhel M. Ghannouchi

Keywords:

• power amplifier
• orthogonal model
• polynomialmodel
• memory effects.

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