Compact Transformer-Based Matching Structures for Ka-Band Power Amplifiers

This paper will highlight the advantages of lumped element matching structures for millimeter wave circuit design. Compared to traditional transmission line structures, which are still widely used in GaAs power amplifiers as they are easy to model over a wide frequency range, transformer-based matching matching structures offer a smaller footprint and thus a more compact design. A Ka-band power amplifier using transformer-based matching structures is implemented in a 0.15μm GaAs technology. The prototype achieves one of the highest power densities for Ka-band GaAs power amplifiers.