It is known that the tempting features of free space Non-Line-Of-Sight (NLOS) communications systems operating in theUltraviolet C-band between 200 and 280 nm are the significantly reduced solar irradiance on ground level, the intensescattering and its combination with strong absorption which ensures the covertness against distant eavesdroppers orjammers. In the majority of the experimental surveys that have been published so far, the performance of point-to-pointlinks has been evaluated under clear atmosphere without taking into account the weather conditions. In this work, it isshown that harsh atmospheric conditions due to fog appearance can be advantageous to short distance NLOStransmissions at 265 nm. Initially, the impact of fog on the losses of the diffuse wireless channels was investigatedtheoretically. Afterwards, an experimental survey of both the losses and the performance of low rate amplitude signals’transmissions for two atmosphere cases followed. Initially, the satisfactory relation between scattering and absorption at265 nm was verified by deploying outdoor NLOS point-to-point links under clear atmosphere. The transmitter consistedof 4 Light Emitting Diodes and the optical part of the receiver included a filter and a Photo-Multiplier tube. Then, thebeneficial impact of artificially generated fog on scattering was exploited not only to enhance the system performancebut also to identify the modification of the conditions. The experimental results showed a clear decrease of both thelosses and the Bit Error Rate under fog conditions making such a system a perfect candidate for low ratecommunications under dense atmosphere.
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