The S-parameters of a transistor at 7.5 GHz with reference to a characteristic impedance of 50
is given by
(a) Using the Rollett factor,
determine if the transistor is unconditionally stable or not.
(b) Using unilateral approximation, determine the maximum transducer gain in dB.
(c) Determine the possible maximum error to be introduced by using the unilateral
approximation. Given the unilateral figure of merit is:
(d) If 18-dB overall gain is desired, change the load reflection coefficient to achieve this gain
by using the constant gain circle approach. Given that the center and the radius of the
power circle at the load side are given by:
Determine the center and radius and then draw the gain circle in the Smith chart.
(e) Choose the load reflection coefficient from the gain circle so that it needs a minimum
number of components for matching.
(f) Determine the component value(s) of the matching network.