REFERENCES

Although resulting errors are very small, we have noted that accuracy depends strongly on the extrinsic parasitic extraction method used to obtain the extrinsic capacitances (Cpg and Cpd) and resistances (Rg, Rs, and Rd). 4. CONCLUSION We have presented a new methodology to determine the small signal equivalent circuit for microwave FET transistors. We have proposed a new set of simple equations to obtain the intrinsic transistor elements of the extended transistor model. These equations are based only on Y-parameters and on differ-ential resistances Rfs and Rfd. The proposed methodology to determine Rfs and Rfd includes the frequency effect in such way that measurements at very low frequencies are not required. Our method was implemented and the equivalent circuit elements for different microwave transistors have been presented. The validity of our method is certified by a direct comparison of measured S-parameters vs. model results, showing a very good agreement of a few percent up to 45 GHz