Experimental characterization of optical power attenuation of 980 nm FSO link in artificial rain-induced environment & mitigation strategy using aperture averaging technique

• Published in: Indian journal of physics 2024, Vol.98 (8), p.2933-2945
• Main Authors: Mukherjee, Shibabrata, Paul, Sujoy, Mazumdar, Saswati
• Format: Article
• Language: English
• Subjects: Apertures; Astrophysics and Astroparticles; Attenuation; Bit error rate; Chambers; Communication; Communications systems; Free-space optical communication; Hazards; Laser beams; Original Paper; Physics; Physics and Astronomy; Rain; Signal to noise ratio
• ISSN: 0973-1458; 0974-9845
• DOI: 10.1007/s12648-023-03055-6

The forecast of rain rate and the accompanying attenuation is a crucial factor for analyzing the efficacy of a terrestrial-based ‘Free Space Optical’ communication technology. The optical beam in a terrestrial-based FSO communication system commonly propagates through open air, where it is susceptible to atmospheric hazards like rain, dust, fog, snow, etc., as a result, the optical beam is diminished by these hazards. In this paper, experimentation has been carried out in the developed artificial rain simulation chamber with a 980 nm Laser source. The considered modulated Laser beam propagates in the different rain rates that are generated by the artificial rain simulation chamber. The obtained optical power attenuation for wavelength (980 nm) is compared with other existing conventional models and developed a new rain attenuation model. With the research of optical power attenuation, the impact of various rain rates on communication channels has been investigated as well, and eventually, an optical power attenuation mitigation strategy known as the "Aperture Averaging" technique has been Introduced in the system. As a consequence, the optical link performance has been improved significantly in terms of received optical power, signal-to-noise ratio, bit error rate, etc., at different rain rate scenarios.