A broadband microwave amplifier using multilayer technology

In this paper, we propose a new broadband microwave amplifier structure using multi layer technology. Thus the design of multilayer interconnections, with combined slotlines and microstriplines, improves the integration of a feedback passive cell and permits to obtain a broadband balanced amplifier without increasing the circuit area. A first part details the structure design and the conception of this feedback cell. In a second part, the method is performed for a microwave amplifier design considering a GaAs FET commonly used in microwave circuits. A large frequency bandwidth of about 500MHz around 4 GHz is obtained. The results concerning the input VSWR, the output one and the gain are then presented. In conclusion the amplifier performances are satisfying and the feasibility of such a structure with the use of the multilayer interconnections is then evidenced.