Free Space Optics (FSO) is an emerging technology in telecom industry providing high data rate and security after optical fibre communication. Due to a few limitations of FSO, a new technique hybrid FSO/RF is gaining market-wide acceptance which has RF as a backup link. This technique is very useful in establishing link between aerial vehicles and the ground stations. The paper focuses on the area of space optics and its limiting spheres. Further, the implications of FSO in airborne communication with the challenges faced by aerial vehicles are discussed. The paper also reports few methods, to combat the problems faced by unmanned aerial vehicles (UAVs) and high altitude platforms (HAPs), which are utilized in recent years to enhance performance. The techniques for future research work are also proposed in the paper.

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Fso Hybrid Fso/rf Unmanned Aerial Vehicles (uavs) High Altitude Platforms (haps) Airborne Internet