Analytical and computer-aided design techniques for bipolar and FET transistor amplifiers

Analytical and computer-aided design techniques for broadband high-frequency bipolar and FET transistor amplifiers are presented. Theoretical results on the optimum gain-band-width limitations are derived using equivalent circuits based on the measured scattering parameters of the transistor, with an arbitrary prescribed transistor gain roll-off characteristic. Optimum limits are derived for both the lumped and commensurate transmission-line distributed element cases, as well as a special case of lumped lossy matching networks. Several analytical design techniques are then presented to derive broadband matching networks which simultaneously provide (1) broadband matching to equalize the intrinsic reactive constraints, (2) broadband impedance transformation without transformers, and (3) compensation for the intrinsic transistor gain roll-off characteristic.