Hi
I designed a gysel power divider (similar to wilkinson) at 12 GHz and its performance is good. But its size is too small for my goal. I want to use a substrate with lower permittivity in order to increase the divider's size. But I don't want its center frequency and other configurations change.
I've never come across a case where a component was "too small" before... why do you want to increase it's size? Obviously changing the host medium will require a redesign.
Actually I used frequency scaling in order to get a Gysel PD working at 12 GHz (and I didn't design it completely). The overall size is less than 15 mm, so I can't use SMA connector at the output ports. If I use a material with lower permittivity, I can increase the width and length of microstrip lines.