ENIT, Tunis, Tunisia
ENSEA/ECIME, Cergy, France,
ENSEA/ECIME, Cergy, France
EPT, La Marsa, Tunisia
SYNCHROINFO JOURNAL. Volume 7, Number 5 (2021). P. 21-25.
The design of microwave circuits needs a good analysis of the performances of the field-effect transistor equivalent circuit. Indeed the small signal equivalent circuit of the field-effect transistors makes it possible to easily determine their performances such as the gain and the noise figure. A field-effect transistor constitutes a propagation structure along its gate width. Telegraphists’ equations are solved for this structure. One deduces from this the effect of the propagation on the transistor Z-parameters which can be taken into account in electric simulations and which may improve the use of long transistors at lower frequencies and of short transistors at higher frequencies.
Keywords: FET equivalent circuit, field-effect transistor, microwave circuits, Z-parameters
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