A multistage amplifier, operating at high frequency, in which the inputs and outputs of each stage are taken from tapped transmission lines. The diagram is a schematic of a distributed FET amplifier using artificial L-C transmission lines at input and output; the amplifying stages are distributed along the transmission lines. The phase velocity along each transmission line must be arranged so that the outputs from each stage add in phase. Distributed amplifiers are very wide bandwidth, providing a reasonable gain up to the transition frequency f_T of each of the transistor stages. In practice, losses and parasitic reactances in the amplifiers and transmission lines limit the upper frequency.

Distributed FET amplifier