A new assessment of pHEMT models by comparing relative errors of drain current and its derivatives up to the third order

At present, there are relatively more precise pHEMT models available for computer-aided design, and they are frequently compared to each other. However, such comparisons are mostly based on absolute errors of drain-current equations and their derivatives. In the paper, a novel method is suggested based on relative root-mean-square errors of both drain current and its derivatives up to the third order. Moreover, the relative errors are then relativized to the best model in each category to further clarify obtained accuracies of the drain current and its derivatives. Furthermore, one our older and two newly suggested models are also included in the comparison with the traditionally accurate Ahmed, TOM2 and Materka ones. The assessment is performed using measured characteristics of a 110 GHz pHEMT. Finally, a usability of the models of the higher-order derivatives is illustrated using an IP3 computation/measurement of a multi-constellation receiver for a satellite navigation with ATF-54143.