Point-to-point optical wireless network for factory communications

An exploratory network has been realised for demonstration of indoor wireless optical networks in a ring configuration. The ring comprised 9 nodes but it is expandable to 128 nodes with the present addressing scheme. The network was primarily designed to transport voice channels but it is easily adaptable to accommodate other information contents, both digital and analogue. Visible lasers (650 nm) were used for improved safety and easier diagnostics of link breaks. The node-to-node distance range was not optimised at all but reported calculations indicate that link distances up to 700 m can be reached for a digital receiver operating at 140 Mbit/s (BER=10^-9)