want help with ports in cst microwave studio

hello all,
i have designed square patch microstrip antenna at 5.8 GHz frequency using single feed...after that i have use two feed and i got the proper impedance matching at both the ports but i m bit confused with do i excite both the port same time?..actually i am getting two results for each of the port coz m exciting these separately.how to excite both the ports in a same time..i am using cst.
please help me..

warm regards,
sonia

You can combine the results of both ports in the post processing, it's not necessary to excite both ports simultaneously. Choose post-processing-> combine results.

dear johnjoe
thank you very much for help..
hello all,
now i am trying to calculate axial ratio vs frequency curve in template based postprocessing..if i am checking it separately at 5.8 GHz then the axial ratio is around 0.95 but at various frequency it is not giving the appropriate result..whats the problem?i am doing something wrong or there is any other method.
i will appreciate your help and time

regards,
sonia

additionl
it is also showing error message that unormalized balance is not available and radiation efficiency and gain are inaccurate

can you post your simulation setup, result and error message?

ya sure...i have obtained the curve of axial ratio vs frequency...but the error message in message window is still there..i m enclosing my all result here...
thank you

additional and error message is
"Unormalized balance is not available and radiation efficiency and gain are inaccurate"

Mhm, why you use two feeds with a delta phase of 90°?

johnjoe,
what it means ?actually i am not getting your answer?please explain..
thank you.......

johnjoe,
what it means ?actually i am not getting your answer?please explain..
thank you.......

I saw in your second farfield result, that you excite both ports with a phase difference of 90 degree, any reasons for it?

for circular polarization
one is at 0 degree and the second one is with phase difference of 90 degree with another one.

hey
here is my project file please check and solve my problem...the error message is a big problem

ok good, I'll check it and post it.

About this warning of unnormalized balance: You can also excite both ports at the same time (no post-processing): Open simulation setup, select source type: Selection and edit in the excitation list your port setup. Hence, you can excite both ports at the same time without warning. Maybe your results will be fine with it.

yes.thnk you very much..
this time no warning message bt one thing more...how to measure axial ratio banddwidth?

i have obtain the curve for axial ratio vs frequency and from curve it is clear that the bandwidth is increased bt how to measure the exact bandwidth?

Maybe use two markers in your diagram.

should i fix the marker at 3 db?the horizontal one

maybe have a look at: http://www.antenna-theory.com/basics/bandwidth.php about bandwidth, but from my understanding, 3db is correct for axial or pol. bandwidth.

yes...thank you..

申明：网友回复良莠不齐，仅供参考。如需专业解答，请学习易迪拓培训专家讲授的CST视频培训教程。