Microstrip highpass filter

[dursun]

Hi,
I am working on a highpass microstrip filter for stop frequency 40GHz on substrate:
er=2.2, h=0.254mm (100mils).
The idea is that, one edge of the microstrip is shorted to the groundplane which ensures, that DC and TEM, qTEM modes are disabled in the structure.

Has anyone came across the problem?? Any sugestions??

Best regards
Ania

 

[amicloud]

can you describe the theory or the structure of your filter ?
I am designing a highpass one.which is constructed by:
a main 50 ohm transmission line. and several parallel short circuited
lines.
I want to change idea with you.my email:lycloud1978@163.com

 

[crenyen]

I had design a microstrip line LOW PASS FILTER for 802.11b and 802.11a WLAN design.
I have no experience on 40GHz HPF design.
I ALSO EAGER TO HOW.

 

[biff44]

100 mil microstrip at er=2.2 at 40 GHz. You should check that with an EM program, I am pretty sure that a substrate that thick will start to multimode well below 20 GHz.

 

[randyding]

must be typo, 0.254mm=10 mil