Acoustic Wave Strategy to Enhance Free-Space Optics Link Performance in Fog Conditions

Free space optics (FSO) provides innovative and cost-effective connectivity for future sixth generation (6G) terrestrial backhaul networks (TBNs). However, atmospheric conditions such as fog and smog can severely disrupt FSO performance. In this paper we proposed for the first time the use of an acoustic wave strategy to mitigate dense fog in FSO to optimise the performance of TBNs. Acoustic agglomeration has previously been studied for fog removal or air purification systems, but seldomly for FSO applications. In this study, an indoor optical chamber was designed to evaluate the proposed system over a propagation link range of 0.6-1.0 m. The results showed that FSO link visibility was improved by 126 m in dense fog, with an improved transmittance up to 65%.