Three different coplanar waveguide-to-slotline transitions on InP for
operation around 30 GHz were designed. The performances of these trans
itions in back-to-back configuration were simulated and measured over
1-50 GHz. They were found to possess wideband characteristics. In part
icular, two of them had bandwidths as large as 35 GHz. The design of t
hese transitions were carried out with the view to monolithically inte
grating tapered slot antennas with coplanar waveguide circuits on InP
substrates.