Why is it difficult?
Free space optics is an alternate technology to optical fibers that is cheaper and more feasible in certain scenarios. They can establish a communication link for terrestrial long-distance networks, satellite communication, or even outer space communication. One of the main difficulties for free-space communication is atmospheric turbulence which mislocates the highly pointed laser beams. Even small vibrations for terrestrial links need to be taken care of, while planetary rotations would be an even bigger challenge for inter-planetary links. This technology requires innovation at every front, from a robust hardware design to digital signal processing algorithms to maintain such a link. In this direction, long-term research in understanding wave propagation in fibers would help understand the free-space optics.
What is the impact?
If realized, the free-space optics has the potential to increase the network capacity while being feasible to deploy in difficult locations where fiber would not be an option. In addition, commercial satellites are in demand, which requires a high capacity link from the satellite to ground stations for surveillance or space imagery applications. As the number of satellites increases, free-space optics would positively impact maintaining their connectivity to the ground station. In the future, the inter-planetary link would be an elusive goal for free-space communication.
