Fiber coupling enhancement in Optical Communication Terminals

Abstract

Global internet traffic is subject to exponential growth. Free Space Optical communication can accommodate for this increase. Current communication systems prove to be capable of transferring Terabits/s of data per link to and from a satellite. This is done by coupling the laser beam into a fiber, which is connected to a computer capable of processing the data in the laser beam. The downside of these systems is that they require position sensors to accurately steer the beam into the fiber. These sensors limit the amount of light reaching the receiver and thereby limit data capacity. Furthermore, these sensors may drift due to thermal loads, causing the system to lose performance. By removing the position sensor and implementing the gradient-based algorithm Extremum Seeking Control, the same performance can be achieved without risk of fiber drift. Furthermore, this approach would reduce system complexity, relax tolerances imposed on these systems and most importantly, increase the average fiber coupling efficiency of satellite links by 40%. This is verified by a simulink model and breadboard experiment.