microstrip antenna impedance

Dear Friends,

From my experience, there are many experienced members at Microstrip antenna in this forum.

I need you help to solve my problem. For experienced person in EM simulation, I believe that my problem can be solved.

I am very interesting in microstrip antenna design and have read a lot of papers written by Prof.Ithoh.from.UCLA.

I have found that circular-sector-microstrip-antenna is the most interested topic for me.

In the following, you can find one paper in the attached file.

In that paper, 120-degree cut-off circular sector microstrip antenna is designed in 740 mil radius with 31 mil height in RT/DUROID5870 substrate.

Problem: Actually this patch antenna is designed for active antenna purpose(with power amplifier). Therefore the input impedance of antenna is the most important parameter in the simulation.
The input impedance is strongly effected not only by the geometry of the patch but aslo on the geometry and position of the microstrip line feed.

But fundamental harmonic(from my simulation) is slightly different from the result of the paper. Input impedance is totally different. But I followed all the parameters used in the paper.

Please help me to solve the problem

I applied ADS2002 for my simulation as well the original paper....

Best regards,EDIN

Dear Friends,

I am still waiting for the feedback from EM/Antenna/ADS expert.....

Topic: How to analysis circular =sector=microstrip=antenna=with=ADS...

Best regards,EDIN