How to simulate a radiation source several hundred meters away?

Hello everyone. I want to simulate a radiation source about 500 meters far away from my receiver antenna board. The receiver antenna board contains 6 same PCB antennas, with half power bandwidth 60*60 degree, and each is controlled by switches to the receiver front end. I just want to simulate the radiation source in different places such as different height or angles, and each of the receiver antenna would produce what different outputs, which is should be implied the information for the range and angles. So what software should I choose? HFSS and ADS might be unfit. Any reply would be helpful and appreciated, and please feel free to answer.

I think your simulation approach is wrong. Because of reciprocity, you can simulate this as a transmit antenna case and study the radiation pattern. That is much more efficient for simulation than using your receice case with plane wave field excitations in the EM model.