Abstract: The goal of this paper is to characterize the nonlinear dynamic behavior of RF power amplifiersusing the general memory polynomial (GMP) model whose coefficients are extracted by the multichannel inverseQR decomposition recursive least-squares (IQRD-RLS) algorithms. The IQRD-RLS approach solves directly forthe time-recursive least squares weight vector, while avoiding the highly serial backsubstitution step required inpreviously derived QRD approaches. Furthermore, the approach employs Givens rotation operations to recursivelyupdate the model coefficients and is suitable to be implemented using systolic array to achieve fast convergenceand good numerical properties. The model is validated by means of ADS simulation data. The result indicates thatmodel is capable of satisfactorily describing the nonlinear dynamic behavior of wideband RF power amplifiers.