Integrated approach to free-space optical communication

Lasers offer tremendous advantages over RF communication systems in bandwidth and security. Atmospheric turbulence causes severe received power variations and high bit error rates (BERs) in airborne laser communication. If two or more laser beams are separated sufficiently, they can effectively "average out" the effects of the turbulence. This requisite separation distance is derived for multiple geometries, turbulence conditions, and turbulence effects. Integrating multiple techniques into a system alleviates the deleterious effects of turbulence without bulky adaptive optics systems. Wave optics simulations show multiple transmitters, receiver and transmitter trackers, and adaptive thresholding significantly reduce BER (by over 10,000 times).