wideband coupler help - microstrip circuit is too large

[cddxdlk]

wideband coupler help?

hello
I want to design a wide band coupler (100MHz-600MHz).But using microstrip circuit is too large.
so my question :
is there some coupler circuit can provide the flat response in this band.
another question:
if the term of the couple changed,(eg the term is 50ohm or the VSWR of the term is 2.5) the freq response would changed.
but in fact ,i found the coupler that designed by R&s ,the change is very small whether the term is 50 or VSWR is 2.5.
so ,how to deal with this question.

thanks

 

[vfone]

Re: wideband coupler help?

https://www.minicircuits.com/pages/pdfs/an30004.pdf

 

[kspalla]

wideband coupler help?

Have you find the directivity?
It is suppose to change drastically if the termination is changed from 1 to 2.5 of VSWR.