Atmospheric Ducting Effect in Wireless Communications: Challenges and Opportunities

Atmospheric ducting has a significant impact on electromagnetic wave propagation. Radio signals that are trapped and guided by the atmospheric duct can travel a much longer distance over the horizon with lower attenuation since the signal power does not spread isotropically through the atmosphere. Atmospheric ducting brings both challenges and opportunities to wireless communications. On one hand, the signals propagating in the atmospheric duct may interfere with a receiver far away as remote co-channel interference. On the other hand, a point-to-point link can be established directly through the atmospheric duct to enable beyond line-of-sight communications. In this article, the formation of the atmospheric duct and its effects on radio wave propagation are first overviewed. Then solutions and standardization activities in the 3rd Generation Partnership Project (3GPP) to mitigate atmospheric duct induced remote interference are presented. Finally, the applications and design challenges of atmospheric duct enabled beyond line-of-sight communications are reviewed and future research directions are suggested.