Review of Free-Space Optical Communications Links

Increased needs for bandwidth require technology that goes beyond traditional copper lines. As internet traffic scales faster than Moore’s law, which is the exponential growth in technology, and digging to install lines in metropolitan areas becomes infeasible, the industry has realized the benefits of free-space optical communication. Free-space optical (FSO) communication links are attractive because they provide a means of low cost, high bandwidth, reduced time-to-market, secure and are a reliable means of communications. This paper examines the benefits of FSO, the general operation of such links, and the difficulties that the field faces. In order to inspire confidence that such links are viable, two systems, UC Berkeley’s Smart Dust and MIT Lincoln Laboratories’s THOR are discussed.