Coherent optical communication over the turbulent atmosphere with spatial diversity and wavefront predistortion

Abstract

Optical communication through the atmosphere has the potential to provide data transmission over a distance of 1 to 100 km at very high rates. The deleterious effects of turbulence can severely limit the utility of such a system, however, causing outages of up to 100 ms. In this paper, we investigate the use of spatial diversity with wavefront predistortion and coherent detection to overcome these turbulence-induced outages. This system can be realized, especially if the turbulence or the receiver is in the nearfleld of the transmitter. New results include closed-form expressions for average bit error rate, outage probability, and power efficiency. Additionally, system performance gains in the presence of a worst-case interferer are presented. These significant results are used to develop design intuition for future system implementation.