HFSS-antenna parameters question

Dear All,

I have tried to simulate a printed antenna. When I read antenna parameters, I got Directivity < 1, gain is very small and a very small radiation efficiency, which indicates an error in simulation. Then I have set the radiation box mesh to about lambda/10, I got reasonable directivity, but the values of gain and efficiency are still too low. Anyone can help? Thanks.

Best Regards,
Mshafee

i think radiation box must be more than wavelenght 1/4

Dear amu811,

Thanks for your reply. The radiation box is lager than lambda/4, but I still get unacceptable gain and efficiency.

Best Regardsd,
Mshafee

Attach you model so that we can take a look at it...

can you upload antenna's HFSS file to forum?
or email it to m_zw@hotmail.com
i try to modified it

How is your return loss ?