Determination of the parameters of the equivalent circuit of the active region of an FET crystal

The relationship between FET crystal parameters and the maximum stable-gain coefficient of the FET is determined, and the results are verified analytically for the case of a Schottky FET. The proposed method of determining the active-region parameters does not require the use of the short-circuit regime or knowledge of the physical parameters of the crystal material; only the signal power and frequency need be measured. The proposed method can also be used to determine the parameters of the equivalent circuit of the active region of a double-gate FET crystal, represented in the form of a series connection of equivalent circuits of single-gate FETs.