Design and implementation of MW balanced amplifier using branch-line couplers

Abstract

The design and implementation of MW balanced amplifier operating at 3.5 GHz have been performed using microstrip technology. A duroid substrate of relative permittivity 2.2, and Motorola MRF-9411, L packaged MW transistors are used. A network computer analysis program has been developed to asses the amplifier performance, and its results are compared to the practical measurements of the implemented schematic. The amplifier provides a power gain of 9 dB with input and output VSWR of 1.65, and 1.35 respectively. Such an amplifier can be used in satellite communication, electronic support measure (ESM) receivers, and airborne radar.