5G Base Station Atmospheric Duct Interference: Predictions Using the Mesoscale WRF Model

Atmospheric ducting is a unique layering structure in the lower troposphere where the gradient of atmospheric refractive index differs from the norm, allowing radio signals to bend and travel along the Earth’s surface. In China’s coastal areas, particularly along the Bohai Sea, Yellow Sea, and East China Sea during the summer, these ducts are closely tied to the monsoon climate. On the North China Plain, the interaction between land high pressure and the subtropical high often results in evaporation ducts forming after rainfall. Low-level atmospheric ducts usually affect frequencies between 30 MHz and 5 GHz, with notable impacts on L, S, and C band radio systems. The TDD (Time Division Duplex) format used by 5G systems is especially vulnerable to such interference.To tackle this issue, this study has developed an atmospheric duct interference prediction model using the mesoscale WRF (Weather Research and Forecasting) model and conducted simulation tests in Pingdu City, Qingdao. The model aims to explore the temporal and spatial variations of atmospheric ducts in the area. By analyzing interference data from all China Mobile base stations in Pingdu City between July 2 and July 13, the study found that the model’s predictions matched the actual interference conditions at the base stations with about 84% accuracy, demonstrating the model’s validity.