Abstract

The Free-space Optics (FSO) is a technology able to provide line-of-sight, wireless and high-bandwidth digital communication links between remote sites [1]; it is also extremely resistant to inter-system interference. Commercially available systems offering capacities up to 2.5, 5 Gbps and more are already available. A new configuration, known as fully transparent, is rising up and the bandwidth achievable in these systems is comparable to fibre one. For transparency is meant launching and collecting power directly through single mode optical fibers [2]. The use of transparent FSO allows the adoption of DWDM transmission enhancing the capacity of optical wireless link exploiting the full capacity of optical fibers. The coupling loss and the atmospheric attenuation limit transparent systems to short-range links, such as hundreds of meters [1]. Our set-up consists of three DFB laser sources (LI, L2, L3) at 1555.75 nm, 1556.55 nm and 1557.35 nm ITU-T wavelengths, carrying a 2.5 and 40 Gbps data rates; the 40 Gbps was obtained by time-multiplexing four 10 Gbit/s electrical sequences with a pattern length of 2³¹-1.

© 2007 IEEE