Extremum seeking control for simultaneous beam steering and wavefront correction

Traditional mechanical methods for laser beam steering and wavefront control such as steering mirrors, gimbals and deformable mirrors are heavy, large and require large amounts of power. In addition reliability can also be an issue for mechanical devices. Liquid crystal based electronic beam steering devices have the potential to overcome these disadvantages. This paper presents an extremum seeking control algorithm for simultaneously performing beamsteering and wavefront control using optical phased arrays for laser communications systems. This approach uses only power-in-fiber sensing for feedback. The algorithm is tested using a model of a free-space laser communication system