A system level model of solid state amplifiers with memory based on a non linear feedback loop principle
Résumé
This paper presents a new behavioral modeling approach for solid state amplifiers (SSAs) used in communication systems. The model topology consists of the combination of two low pass equivalent transfer functions that process the envelope of the signal. The first one is a nonlinear filter which is well suited to handle short term memory effects. The second one is a nonlinear impulse response that takes into account long term memory effects. In the present paper, the proposed behavioral model is extracted from harmonic balance and envelope simulation results of a BiCMOS LNA and a HBT PA. It is then tested for the prediction of the amplifier response to a 16-QAM signal.