Long-range free-space inter-island optical communications in offshore surface environment

A prototype laser communication system has been proposed and experimentally demonstrated for long-distance and high-speed laser communication in the marine environment. The transmission loss of a long-distance laser communication link has been theoretically evaluated. A laser communication system has been built for long-distance inter-island laser communication and high-speed laser communication with a bit error rate (BER) of 1.09×10−10 has been achieved between two 29-km offshore islands. Continuous communication experiment indicates that the BER is no more than 10×10−6 for 94.05% of the optical signals with good communication stability. Our proposed communication system would be of significance for related studies regarding the stability of near-Earth surface space laser communications.