Impact of the boundary layer on pointing and tracking in airborne free-space laser communication links

Free-space laser communication is a developing technology with enormous potential to revolutionize the way people communicate across the globe. Of specific interest are air-to-space lasercom links. Such a link experiences atmospheric scintillation, platform jitter, and boundary layer turbulence. This research investigated the tracking challenge using a focal plane array sensor with centroid and peak tracking algorithms. Also investigated was the use of a deformable mirror to recreate optical phase distortions from boundary layer turbulence. Experiments were conducted with realistic channel effects for multiple look angles between a subsonic aircraft at 29 kft and geosynchronous satellite. Performance was determined by power delivered to an optical fiber. The results show that the two tracking algorithms can differ by up to one decibel of fiber power, with centroid tracking generally performing best. Conclusions are highly dependent on aircraft and spacecraft parameters but point towards centroid tracking for maximizing received power. Keywords: Lasercom, FPA Tracking, Boundary Layer Disturbances, Deformable Mirror.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2008

Author dc:creator

• Conrad, Ross Aaron

Advisor dc:contributor.advisor

• John J. Deyst and Jeffrey M. Roth.

• Aeronautics and Astronautics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/44929

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/44929