The determination of the transistor dynamic I-V characteristic from large signal RF measurements

An analysis technique has been developed that allows for the determination of the transistor dynamic I-V characteristics (RF l-V) directly from CW large signal RF measurements. A key feature of this technique is that it is performed under RF operation conditions similar to those found in power amplifiers under CW RF drive conditions. Investigations have shown that these dynamic RF I-V´s are independent of initial DC bias conditons and RF drive level for the MODFET structures investigated in this paper. These dynamic RF I-V´s can be directly compared with DC I-V´s to allow for the investigation of phenomenas like dispersion, RF breakdown and thermal effects etc.. To demonstrate their potential capability in the area of non-linear modelling these RF I-V´s have been used for non-linear parameter extraction of a relatively simple large signal model. A good comparison between the simulated and measured large signal behaviour even for the higher harmonics has been achieved.