Design considerations for MMIC distributed amplifiers

Abstract

The bandwidth of the input artificial line in a distributed amplifier is the main band limiting factor. By choosing this impedance properly the bandwidth of a distributed amplifier can be maximized. A four section GaAs MESFET distributed amplifier is designed using this strategy. The fabricated MMIC amplifier gives satisfactory performance. By adding proper length of series transmission lines in the drain side, the gain and the gain flatness of the amplifier can be further improved. This fact is presented via simulation results. The superior gain potential of cascode connected FETs is also demonstrated.