Spatial-Temporal-Frequency Interference Correlation in Low-Altitude Economy UAV Networking

As a significant restricting factor of the network performance, interference correlation affects the design of diversity schemes. In this paper, we propose a stochastic geometrybased approach to characterize the spatial-temporal-frequency correlation of interference in low-altitude economy unmanned aerial vehicle (UAV) networking. Incorporating the salient air-toground propagation properties, we first derive the temporal and frequency correlation coefficients of the interference at the same location to characterize the interference correlation of a ground device across both temporal and frequency domains. We then extend to the spatial-temporal-frequency correlation coefficient quantifying the interference correlation of two different ground devices. Using the proposed analytical framework, we are able to show that the correlation is not affected by the deployment density of UAVs but subject to the UAV's height. Numerical results indicate that the correlation increases as UAVs operate from urban to suburban areas due to a higher line of sight probability in suburban areas. Additionally, the correlation decreases owing to the independence of channel fading.