Compact, wideband CPW-to-slotline multimodal transition

This paper presents and implements a number of configurations for compact, wideband, low-loss, uniplanar coplanar (CPW)-to-slotline transitions. These are modelled using a multimodal model and it is theoretically and empirically proved what are the main design parameters and their influence on the final transition performance. An optimized transition topology is implemented on alumina, featuring a state-of-the-art maximum insertion loss lower than 0.7 dB in the frequency band from DC to 50 GHz, with a reduced area of 0.105 mm².