assxdf
Newbie level 6
hi everyone
i'm working on the KU band filter,12Ghz. The stripline filter confused me for a long time. i designed the filter use the RO4003 in HFSS.
i test it use the via. The result was so bad ,the center frequence shifted to the left about 400M .The top of the curve is not flat so much.Test results and simulation results are quite different.
in my opinion, there are perhaps two reasons :
(1)the RO4003 has two versions of the dielectric constant ,3.38 and 3.55. I used 3.38 ,maybe i should use 3.55 to design. i don't konw which one should i use. does anybody know that? please help me, thx.
(2)the bad test result maybe brought by via. dose any one has the experence of using via in such band ? The frequence is so high, the via maybe bring bad S11 and S21. dose anyone known that, please help me,thx.
i'm working on the KU band filter,12Ghz. The stripline filter confused me for a long time. i designed the filter use the RO4003 in HFSS.
i test it use the via. The result was so bad ,the center frequence shifted to the left about 400M .The top of the curve is not flat so much.Test results and simulation results are quite different.
in my opinion, there are perhaps two reasons :
(1)the RO4003 has two versions of the dielectric constant ,3.38 and 3.55. I used 3.38 ,maybe i should use 3.55 to design. i don't konw which one should i use. does anybody know that? please help me, thx.
(2)the bad test result maybe brought by via. dose any one has the experence of using via in such band ? The frequence is so high, the via maybe bring bad S11 and S21. dose anyone known that, please help me,thx.