Design and Investigation of Free Space Optical System for Diverse Atmospheric Transmission Windows

Abstract Free space optics is a light-wave communication technology that operates in the near-infrared region of the electromagnetic spectrum (about 700–1675 nm) and uses atmospheric channel as the transmission medium for both inter-satellite and terrestrial networks. However, the operational proficiency of free space optical communication system is highly affected by channel dynamics which cause signal attenuation that results in short link range. To master these shortcomings different methods have been suggested in the literature, from transceiver design and diverse channel models to adaptive algorithms. In this manuscript, the design and performance investigation of free space optical system has been carried out for three optical transmission windows; 850, 1310 and 1550 nm by means of on-off keying digital modulation technique. The system analysis has been done taking bit error rate, quality factor and received optical power as the performance metrics. Their variation pattern with respect to varying link parameters such as range, transmitted optical power and beam divergence has been investigated. In addition, the observations made are well validated with thorough mathematical justification.