Analysis of interference from UAV system to adjacent 3.5GHz land-based radar system

Due to the rapid expansion of the unmanned aerial vehicle (UAV) industry, numerous application scenarios for UAVs have emerged. When UAS fly at high altitude, especially when 5G base stations or terminals are carried by UAS operating in the 3.5 GHz frequency range, the out-of-band signals emitted can pose serious interference risks to radiolocation services using nearby frequencies. In this paper, we analyze in detail the analysis method of inter-system interference compatibility by combining the ITU-R proposal and the actual deployment parameters of UAS. Then the deterministic calculation and analysis of the neighboring frequency interference between UAS and ground radar systems is performed. The analysis results show that the strictest interference occurs when the interference signal from the UAS enters the main band of the ground-based radar. And when the UAS and the radar system are farther apart in frequency, the interference is less. And the interference caused by the UAS carrying the base station is greater than the interference caused by the UAS carrying the terminal.