in the attached paper, the frequency is 6GHz,but the transformer is 4.922mm long,not lambda/4 at all. why is that?
And in caculating the resistance Zin of patch, I get G1=0.0025, G12=0.0042,it seems not a right result!
Re: caculation of quarter wave transformer in microstrip ant
Dear ljx1067
you need to know that in papers the author not allays give you the exact
design. he gives you the start of his work and the end of it and then let you to figure what is missing between.
about the λ/4 the coupling between the patch and transformer also radiation from patch and thin line
cause to the change in dimantion.