GaN HEMT device modeling using X-parameters with emphasis on complexity reduction of harmonic load-pull measurement

To characterize a power transistor, a fully harmonic load-pull test setup is normally required, which leads to relatively high complexity of the measurement. This paper explores the potential of X-parameters in reducing of the complexity of the harmonic load-pull measurement for power transistor modeling. A 6W GaN RF power transistor is modeled by load-dependent X-parameters by simulations on its compact model. During the simulation, the load impedance of the device is tuned only up to the second-order harmonic. However, it proves that the created X-parameter model can still precisely predict the behavior of the (compact model of) device under load impedance tuning up to the third-order harmonic. The simulation results preliminarily validate the concept of utilizing the X-parameter-based modeling technique to reduce the complexity of a harmonic load-pull measurement setup.