Elliptical monopole antenna

I have design the PEMA for the UHF band around the center frequency 460 MHz and I have got the results around the 456 MHz and when i am trying to check E & H field it only can radiate onto the port. Please tell me what changes should i do that will trigger the port and whole ground plane and antenna is able to radiate ? I have attached the CST File and Parameters also.

Does anyone have the tutorial of CST about the printed elliptical monopole antenna ? kindly share it.

Thank You.