Analysis of a Microwave Diplexer-HELP

[lalindadef]

guys,

I have attached some images of something i've been working on. I designed a diplexer using open loop filters and a dual band Wilkinson Power divider. After simulations and all, i tried doing some test fabrication on FR 4, which was also quite good.

But the actual fabrication was done using an Old piece of Metclad ( D.C. =10.8, thickness 1.55mm). The process of toner transferring was really difficult, and i did it a few times, but since i was running out of time proceeded with what i could get. The close up is of the Wilkinson Power Divider fabricated. The toner transfer wasn't good, the lines were supposed to be 0.35mm, but as it can be seen, the lines are really messed up.

The question i have is that, when looking at the results, u will see that S21 is quite odd,being well below S11, is this because of power divider lines are not uniform??

Would be a real help if i can get some logical insights in to analyzing the problem..

Thanks in advance..

 

[volker_muehlhaus]

I believe that it's not only the wrong/changing line width, but also wrong/changing gap width in the filters.