Results of 150-km, 1-Gbps lasercom validation experiment using aircraft motion simulator

Laser communications between high flying aircraft such as high altitude unmanned aerial vehicles and between the aircraft and the ground (weather permitting) offers the potential to transfer extremely high amounts of information faster and with a smaller package than is currently possible with a radio frequency and microwave technologies. Over the last few years, BMDO has funded a number of technology efforts through the U.S. Army Space and Strategic Defense Command reducing the risks associated with laser communications. One of these efforts, at ThermoTrex Corporation in San Diego, California, is now being carried forward towards an advanced technology demonstration. The program will lead to the demonstration of high data rate communications of 274 Mbit/s to 1.2 Gbit/s between high altitude aircraft and between a satellite and the ground. To identify and further reduce the risks associated with operating the lasercom system on a high flying aircraft, a demonstration of a long range link in the presence of simulated aircraft motion was performed. Link acquisition utilizes an interface to an inertial navigation unit for initial pointing and atomic line filter technology for background light rejection. In addition, data was taken on the effects of atmospheric turbulence on the intensity of received laser light across the 150 km path. We present the development of the tracking system and results of the experiment performed at Mauna Loa, Hawaii and Haleakala, Maui in May and September 1995.