Propagation effects on a FET access resistance

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. New elements have been added to the equivalent circuit in order to take into account the propagation phenomena