The electromagnetic environment of low-altitude airspace has become extremely complex due to the rapid advancement of radio technology. In particular, the electromagnetic energy of HIRF (High Intensity Radiation Field) that is frequently emitted by radar, radio stations, radios, and various ships/airborne impacts negatively aircraft flight safety. In this paper, based on the modeling of a consumer UAV, the HIRF effect is simulated using UWB-HPM, and the electric field variation law at key position and antenna coupling law of the UAV under plane wave irradiation in different directions are analyzed with the help of CST simulation software. The results show that for front-door coupling, the shorter the pulse width of the interference signal is, the stronger the interference for the antenna is, while for back-door coupling, irritation direction and pulse width play a significant role in the coupling effect.