Coplanar Waveguides Used in 2-18 GHz Distributed Amplifier

This paper describes the use of coplanar waveguide as an alternative transmission medium in a monolithic distributed amplifier. The coplanar waveguide layout substantially reduces coupling effects between adjacent lines, and eliminates the need for via holes and substrate thinning, leading to higher fabrication yields. The resulting device reported here is a compact (1.3 x 1.5mm) low noise distributed amplifier on a thick GaAs substrate (15 mil), with a gain of 6.0 +- 0.5dB over the frequency range of 2 - 18GHz.