Propagation effects on Z Parameters in an FET equivalent circuit

M. Balti,
ENIT, Tunis, Tunisia

D. Pasquet,
ENSEA/ECIME, Cergy, France,

M. Ariaudo,
ENSEA/ECIME, Cergy, France

A. Samet,
EPT, La Marsa, Tunisia

DOI: 10.36724/2664-066X-2021-7-5-21-25

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.

KeywordsFET equivalent circuit, field-effect transistor, microwave circuits, Z-parameters


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