Continuous-Time Model Identification of RF Power Amplifiers

Mourad Djamai (1) , Smail Bachir (2) , Claude Duvanaud (2)

1 LAII [Poitiers] - Laboratoire d'automatique et d'informatique industrielle [EA 1219]
2 SIC - SIGNAL-IMAGE-COMMUNICATION

The Radio Frequency Power Amplifier is the major source of the nonlinear distortion which affect the signal modulated in the Radiocommunication transmission system. To analyse and treat the distortion caused to the amplified signal, this paper presents the parameters estimation of a behavioral model. Based on baseband signals, this model includes a polynomial function representing AM/AM and AM/PM characteristics in addition with MIMO continuous filter to describe the PA dynamics. Using the baseband input and output data, model parameters are obtained recursively by an iterative identification algorithm based on Output Error method. Initialization and excitation problems are resolved by an association of a new technique using initial values extraction with a multi-level binary sequence input exciting all PA dynamics. Finally, the proposed estimation method is tested and validated on experimental data.

Mots clés: Nonlinear distortions; power amplifier; linear filter; continuous time domain; identification algorithm; Output Error technique

Domaines: Electronique; Automatique / Robotique

Mourad Djamai, Smail Bachir, Claude Duvanaud. Continuous-Time Model Identification of RF Power Amplifiers. Journal of Microwaves, Optoelectronics and Electromagnetic Applications, 2007, 2 (6), pp.398-405. ⟨hal-00782421⟩