Behavioral Modeling of GaN FETs: A Load-Line Approach

Theoretical consideration on harmonic manipulated amplifiers based on experimental data

“…The aim is investigating and comparing the electrical performance of the device under two different classes of 978-1-4673-6496-6/15/$31.00 ©2015 IEEE operation exploiting harmonic manipulation, i.e., TL [2] and Class F [3], in order to experimentally verify the theoretical data predicted by simplified models and, at the same time, give a validation of the low-frequency methodology used for tests. The measurement setup is based on multi-harmonic excitations [7], [8]: a f 0 = 2 MHz fundamental frequency is conveniently adopted in order to operate above the cut-off of the low-frequency dispersive effects [9], and to neglect the transistor linear and nonlinear reactive phenomena. Such a setup operates as a vector multi-harmonic active load-pull system: by controlling the amplitude of gate and drain incident waveforms and their relative phase, different load terminations can be arbitrarily synthesized at the fundamental and harmonic frequencies for a given bias condition.…”

A Non-Quasi-Static FET Model Extraction Procedure Using the Dynamic-Bias Technique

“…As a matter of fact, an extraction procedure is typically based on one or more measurement techniques (e.g., [3]- [5]), which allow one to observe the device behavior under different operating conditions, jointly with an extraction algorithm, which relies on analytical procedures or numerical optimizations to minimize the discrepancies between model predictions and measurements. Clearly, the measurements used in the identification phase represent a set of privileged conditions for which the model will show its best accuracy.…”

“…DOUBLE-TICKLE DYNAMIC-BIAS TECHNIQUE The dynamic-bias technique [6] exploits the possibility of setting the traps-occupation and thermal states of the transistor by a low-frequency (LF) multi-harmonic load-pull system [5]. At LF the transistor operation, from mixing [6] to high-efficiency power amplification [7], can be simply forced avoiding the use of expensive microwave instrumentation and overcoming LSNA bandwidth limitations.…”

“…The proposed characterization technique is fully able to account for transistor LF dispersion [5], [7]. Nevertheless, since the selected technology is not affected by severe dispersion, we used a simplified transistor description based on the Angelov model [1], [9] whose equivalent-circuit topology is reported in Fig.…”

Hybrid Nonlinear Modeling Using Adaptive Sampling

“…The other way of constructing a hybrid model is to propagate or add the response of one type of model through the response of a second model. This solution is particularly useful when used to combine a behavioral model for the nonlinear transistor core and an empirical model for the parasitic components [3], [13]- [15].…”