Autonomous Alignment of Free-Space-Optical Links Between UAVs

Free-Space-Optical (FSO) communication has the potential to make high data rate point-to-point transfers possible. Despite its capacity advantages, FSO communication (FSOC) requires establishment and maintenance of line-of-sight (LOS) alignment. We consider two Unmanned Aerial Vehicles (UAVs), each with one FSO transceiver mounted on a hemispherical structure/head capable of rotating 360\degree~in the horizontal plane and 180 degree in the vertical plane. We propose a novel scheme that deals with the problem of automatic establishment and maintenance of LOS alignment between the UAVs with mechanical steering of the FSO transceivers. The proposed method shows that using such mechanically steerable transceivers and a simple auto-alignment mechanism, it is possible to maintain an optical wireless link between two UAVs with nominal disruption.