Method and apparatus for compensating for atmospheric distortion

A method for compensating for atmospheric distortion of a free space optical beam comprising:

• generating the free space optical beam;
• propagating the free space optical beam through a disc that is rotationally-balanced and that comprises a phase-modifying structure;
• propagating the free space optical beam through open air so as to impinge on a point in space where reducing scintillation is desired after the free space optical beam has passed through the disc;
• and
• spinning the disc about an axis that is parallel to the free space optical beam so as to reduce, at the point in space, scintillation effects caused by propagation of the free space optical beam through atmospheric turbulence in the open air.

A method for compensating for atmospheric distortion of a free space optical beam comprising:

• generating the free space optical beam, wherein the free space optical beam is a free space optical communication signal, and wherein the free space optical beam is a pulsed LASER having a pulse repetition rate, and further comprising spinning the disc at a rate based on the LASER pulse repetition rate so as to impart independent phase realizations on the LASER so the spinning disc does not to get stuck in frequency nodes between the disc spin rate and the LASER pulse repetition rate;
• propagating the free space optical beam through a disc that is rotationally-balanced and that comprises a phase-modifying structure and a plurality of N tracks, each track configured to apply a different degree of partial coherence to the free space optical beam;
• propagating the free space optical beam through open air so as to impinge on a point in space where reducing scintillation is desired after the free space optical beam has passed through the disc;
• spinning the disc about an axis that is parallel to the free space optical beam so as to reduce, at the point in space, scintillation effects caused by propagation of the free space optical beam through the open air;
• adjusting a rotational speed of the disc with a processor operatively coupled to the rotator;
• and
• using a processor to instruct a linear actuator to move the disc in a direction that is orthogonal to the free space optical beam so as to bring the free space optical beam into contact with different tracks until a desired track is identified that increases a signal-to-noise ratio (SNR) of the free space optical communication signal as compared to a reference track that has a uniform phase profile.