2.5 Gbit/s free space optical link over 4.4 km

Abstract

A new record in terrestrial free space optical transmission, 2.5 Gbit/s (single channel) over a 4.4 km range is reported. Optical data are transmitted over a horizontal path through the atmosphere, error free, using a specially designed optical telescope-transceiver, a conventional 1550 nm laser transmitter, 2.5 Gbit/s receiver/regenerator and a high power optical amplifier.