Performances prediction of an ultra broad-band voltage-controlled attenuator using Schottky contact coplanar line properties

The performance of Schottky contact coplanar lines used as voltage-variable attenuators is discussed and demonstrated with a first realization on F.E.T. epitaxy. It is shown that the use of lower doped epitaxies offers more interesting characteristics. Then, an attenuator is proposed, the theoretical performances of which are: broad-band capability, low loss for ON state, low S.W.R. This device can be operated over a wide band without important mismatch.