In this work, three different model

In this work, three different models have been evaluated concerning their applicability in a hybrid time- and frequencydomain TWT simulation. For this purpose, they have been compared to measurements and simulation results in a variety of multi-tone scenarios. It has been shown that for a real communications TWT at typical operating conditions and practically relevant frequency spacings, the basic SGC model using the Hilbert transform is sufficient to predict the powers at the intermodulation levels. An extension using multiple AM-AM and AM-PM results over a range of frequencies only improves the estimation of the intermodulation products for selected, more dispersive scenarios. The prediction of the phase transfer, on the other hand, can benefit from the more sophisticated models. Additionally, a sequence reduction scheme for the approximate generation of modulated signals has been presented. It enables the meaningful comparison of the envelope models with interaction simulation and yields high accuracy.