This paper presents behavioral modeling of an
envelope tracking (ET) power amplifier (PA) excited by an slewrate
limited envelope. In order to relax the slew-rate
requirements of current efficient envelope amplifiers (EA), we
can drive the ET PA with a slower version of the signal’s
envelope. However, the resulting amplified signal suffers from
nonlinear distortion due to the time-variant gain effects that
arise when using the slower version of the signal’s envelope. In
this paper this time-variant effects are presented and
characterized. A new envelope-dependent (ED) behavioral
model is presented and compared with a simpler static AM-AM
and AM-PM modeling. Experimental results showing the
performance of the proposed ED model were obtained with an
ET PA based on a GaN transistor.
CitacióMontoro, G.; Gilabert, Pere L.; Vizarreta, P. Incremental behavioral modeling of envelope-dependent nonlinear distortion in dynamic supply power amplifiers. A: Unión Científica Internacional de Radio (URSI). Congreso. "XXVI Unión Científica Internacional de Radio (URSI)". Leganés: Unión Científica Internacional de Radio, 2011.