Free-Space Optics (FSO) can transmit high data rate, up to 10 Gbps from several meters to kilometers, depending on meteorological conditions. They are potential candidates in overcoming high data rate and longer last miles connexion needs in the context of development of mobile broadband networks in many countries. The performances and availability of FSO systems are generally affected by weather conditions. In that paper we investigate on the reliability and resilience of a 5 km FSO link simulated by using visibilities data recorded from Dakar city.
The Percentages of availabilities, the power margins, optimal relays placement, and architecture are proposed when operating conditions vary from clear atmosphere to heavy rain or in presence of heavy dust. During these bad weather conditions, often occurred in tropical climate, the effect of turbulence induced irradiance fluctuation, varying beam divergence angle and misalignment issues were analyzed and estimated. In addition lognormal distributions are established to make easy use of channel modeling and survey of FSO systems in similar physical environments.

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• Senegal

• The poor
• remote and rural communities

The project is a feasibility study of the FSO technologie, in a tropicl weather climate. In that regards, the result of the studies, the implementions succes, can be replicated in any other area with same climate conditions, and also with similar social and economic profile, or similar ICT/Telecom infrastructure development.

the project results and implementation can help to develop infrastucutures of Telecom/ICTs and accessibility (in terms of cost and availability) and in term of inclusion of rural and remote area.

In many least developed countries, like Senegal, telecommunications systems are emerging with deployment of metro core access in optical fiber and Digital Subscriber Lines (DSL) to provide high data rate to end users. But last mile, stills inaccessible, very far to end users. However the FSO can solve the last mile problem by offering distance of connection up to 5 km, and high data rate in our case study, representing a typical Sahelian area, Dakar. As there is no known study on the effects of weather conditions in this country, this paper offers an attempt to analyze and identify the challenges related to the deployment and optimization of FSO systems under Senegalese’s weather.The mathematical approximation used for the analyses are easily reproducible and by the way, will facilitate practitioners engineering matters. The project proposes a FSO technolgy which is low cost and high data rate, in that regard, the result can be used by country with similar profil in terms of Telecom infrastructure development and national income.